linux-surface/patches/5.19/0005-surface-sam.patch

From 10cd88124de652804f308111320a863b55da23a0 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 27 May 2022 04:34:36 +0200
Subject: [PATCH] platform/surface: aggregator: Allow is_ssam_device() to be
 used when CONFIG_SURFACE_AGGREGATOR_BUS is disabled

In SSAM subsystem drivers that handle both ACPI and SSAM-native client
devices, we may want to check whether we have a SSAM (native) client
device. Further, we may want to do this even when instantiation thereof
cannot happen due to CONFIG_SURFACE_AGGREGATOR_BUS=n. Currently, doing
so causes an error due to an undefined reference error due to
ssam_device_type being placed in the bus source unit.

Therefore, if CONFIG_SURFACE_AGGREGATOR_BUS is not defined, simply let
is_ssam_device() return false to prevent this error.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220527023447.2460025-2-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 include/linux/surface_aggregator/device.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/include/linux/surface_aggregator/device.h b/include/linux/surface_aggregator/device.h
index cc257097eb05..62b38b4487eb 100644
--- a/include/linux/surface_aggregator/device.h
+++ b/include/linux/surface_aggregator/device.h
@@ -177,6 +177,8 @@ struct ssam_device_driver {
 	void (*remove)(struct ssam_device *sdev);
 };
 
+#ifdef CONFIG_SURFACE_AGGREGATOR_BUS
+
 extern struct bus_type ssam_bus_type;
 extern const struct device_type ssam_device_type;
 
@@ -193,6 +195,15 @@ static inline bool is_ssam_device(struct device *d)
 	return d->type == &ssam_device_type;
 }
 
+#else /* CONFIG_SURFACE_AGGREGATOR_BUS */
+
+static inline bool is_ssam_device(struct device *d)
+{
+	return false;
+}
+
+#endif /* CONFIG_SURFACE_AGGREGATOR_BUS */
+
 /**
  * to_ssam_device() - Casts the given device to a SSAM client device.
  * @d: The device to cast.
-- 
2.38.0

From 491afd847e8b97631743293a1e88d1019038a710 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 27 May 2022 04:34:37 +0200
Subject: [PATCH] platform/surface: aggregator: Allow devices to be marked as
 hot-removed

Some SSAM devices, notably the keyboard cover (keyboard and touchpad) on
the Surface Pro 8, can be hot-removed. When this occurs, communication
with the device may fail and time out. This timeout can unnecessarily
block and slow down device removal and even cause issues when the
devices are detached and re-attached quickly. Thus, communication should
generally be avoided once hot-removal is detected.

While we already remove a device as soon as we detect its (hot-)removal,
the corresponding device driver may still attempt to communicate with
the device during teardown. This is especially critical as communication
failure may also extend to disabling of events, which is typically done
at that stage.

Add a flag to allow marking devices as hot-removed. This can then be
used during client driver teardown to check if any communication
attempts should be avoided.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220527023447.2460025-3-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 include/linux/surface_aggregator/device.h | 48 +++++++++++++++++++++--
 1 file changed, 45 insertions(+), 3 deletions(-)

diff --git a/include/linux/surface_aggregator/device.h b/include/linux/surface_aggregator/device.h
index 62b38b4487eb..6df7c8d4e50e 100644
--- a/include/linux/surface_aggregator/device.h
+++ b/include/linux/surface_aggregator/device.h
@@ -148,17 +148,30 @@ struct ssam_device_uid {
 #define SSAM_SDEV(cat, tid, iid, fun) \
 	SSAM_DEVICE(SSAM_DOMAIN_SERIALHUB, SSAM_SSH_TC_##cat, tid, iid, fun)
 
+/*
+ * enum ssam_device_flags - Flags for SSAM client devices.
+ * @SSAM_DEVICE_HOT_REMOVED_BIT:
+ *	The device has been hot-removed. Further communication with it may time
+ *	out and should be avoided.
+ */
+enum ssam_device_flags {
+	SSAM_DEVICE_HOT_REMOVED_BIT = 0,
+};
+
 /**
  * struct ssam_device - SSAM client device.
- * @dev:  Driver model representation of the device.
- * @ctrl: SSAM controller managing this device.
- * @uid:  UID identifying the device.
+ * @dev:   Driver model representation of the device.
+ * @ctrl:  SSAM controller managing this device.
+ * @uid:   UID identifying the device.
+ * @flags: Device state flags, see &enum ssam_device_flags.
  */
 struct ssam_device {
 	struct device dev;
 	struct ssam_controller *ctrl;
 
 	struct ssam_device_uid uid;
+
+	unsigned long flags;
 };
 
 /**
@@ -251,6 +264,35 @@ struct ssam_device *ssam_device_alloc(struct ssam_controller *ctrl,
 int ssam_device_add(struct ssam_device *sdev);
 void ssam_device_remove(struct ssam_device *sdev);
 
+/**
+ * ssam_device_mark_hot_removed() - Mark the given device as hot-removed.
+ * @sdev: The device to mark as hot-removed.
+ *
+ * Mark the device as having been hot-removed. This signals drivers using the
+ * device that communication with the device should be avoided and may lead to
+ * timeouts.
+ */
+static inline void ssam_device_mark_hot_removed(struct ssam_device *sdev)
+{
+	dev_dbg(&sdev->dev, "marking device as hot-removed\n");
+	set_bit(SSAM_DEVICE_HOT_REMOVED_BIT, &sdev->flags);
+}
+
+/**
+ * ssam_device_is_hot_removed() - Check if the given device has been
+ * hot-removed.
+ * @sdev: The device to check.
+ *
+ * Checks if the given device has been marked as hot-removed. See
+ * ssam_device_mark_hot_removed() for more details.
+ *
+ * Return: Returns ``true`` if the device has been marked as hot-removed.
+ */
+static inline bool ssam_device_is_hot_removed(struct ssam_device *sdev)
+{
+	return test_bit(SSAM_DEVICE_HOT_REMOVED_BIT, &sdev->flags);
+}
+
 /**
  * ssam_device_get() - Increment reference count of SSAM client device.
  * @sdev: The device to increment the reference count of.
-- 
2.38.0

From bebd8ac867acf177167fd156f5e7bcfd36869c52 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 27 May 2022 04:34:38 +0200
Subject: [PATCH] platform/surface: aggregator: Allow notifiers to avoid
 communication on unregistering

When SSAM client devices have been (physically) hot-removed,
communication attempts with those devices may fail and time out. This
can even extend to event notifiers, due to which timeouts may occur
during device removal, slowing down that process.

Add a parameter to the notifier unregister function that allows skipping
communication with the EC to prevent this. Furthermore, add wrappers for
registering and unregistering notifiers belonging to SSAM client devices
that automatically check if the device has been marked as hot-removed
and communication should be avoided.

Note that non-SSAM client devices can generally not be hot-removed, so
also add a convenience wrapper for those, defaulting to allow
communication.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220527023447.2460025-4-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 .../driver-api/surface_aggregator/client.rst  |  6 +-
 .../platform/surface/aggregator/controller.c  | 53 ++++++++++-----
 include/linux/surface_aggregator/controller.h | 24 ++++++-
 include/linux/surface_aggregator/device.h     | 66 +++++++++++++++++++
 4 files changed, 128 insertions(+), 21 deletions(-)

diff --git a/Documentation/driver-api/surface_aggregator/client.rst b/Documentation/driver-api/surface_aggregator/client.rst
index e519d374c378..27f95abdbe99 100644
--- a/Documentation/driver-api/surface_aggregator/client.rst
+++ b/Documentation/driver-api/surface_aggregator/client.rst
@@ -17,6 +17,8 @@
 .. |SSAM_DEVICE| replace:: :c:func:`SSAM_DEVICE`
 .. |ssam_notifier_register| replace:: :c:func:`ssam_notifier_register`
 .. |ssam_notifier_unregister| replace:: :c:func:`ssam_notifier_unregister`
+.. |ssam_device_notifier_register| replace:: :c:func:`ssam_device_notifier_register`
+.. |ssam_device_notifier_unregister| replace:: :c:func:`ssam_device_notifier_unregister`
 .. |ssam_request_sync| replace:: :c:func:`ssam_request_sync`
 .. |ssam_event_mask| replace:: :c:type:`enum ssam_event_mask <ssam_event_mask>`
 
@@ -312,7 +314,9 @@ Handling Events
 To receive events from the SAM EC, an event notifier must be registered for
 the desired event via |ssam_notifier_register|. The notifier must be
 unregistered via |ssam_notifier_unregister| once it is not required any
-more.
+more. For |ssam_device| type clients, the |ssam_device_notifier_register| and
+|ssam_device_notifier_unregister| wrappers should be preferred as they properly
+handle hot-removal of client devices.
 
 Event notifiers are registered by providing (at minimum) a callback to call
 in case an event has been received, the registry specifying how the event
diff --git a/drivers/platform/surface/aggregator/controller.c b/drivers/platform/surface/aggregator/controller.c
index b8c377b3f932..6de834b52b63 100644
--- a/drivers/platform/surface/aggregator/controller.c
+++ b/drivers/platform/surface/aggregator/controller.c
@@ -2199,16 +2199,26 @@ static int ssam_nf_refcount_enable(struct ssam_controller *ctrl,
 }
 
 /**
- * ssam_nf_refcount_disable_free() - Disable event for reference count entry if it is
- * no longer in use and free the corresponding entry.
+ * ssam_nf_refcount_disable_free() - Disable event for reference count entry if
+ * it is no longer in use and free the corresponding entry.
  * @ctrl:  The controller to disable the event on.
  * @entry: The reference count entry for the event to be disabled.
  * @flags: The flags used for enabling the event on the EC.
+ * @ec:    Flag specifying if the event should actually be disabled on the EC.
  *
- * If the reference count equals zero, i.e. the event is no longer requested by
- * any client, the event will be disabled and the corresponding reference count
- * entry freed. The reference count entry must not be used any more after a
- * call to this function.
+ * If ``ec`` equals ``true`` and the reference count equals zero (i.e. the
+ * event is no longer requested by any client), the specified event will be
+ * disabled on the EC via the corresponding request.
+ *
+ * If ``ec`` equals ``false``, no request will be sent to the EC and the event
+ * can be considered in a detached state (i.e. no longer used but still
+ * enabled). Disabling an event via this method may be required for
+ * hot-removable devices, where event disable requests may time out after the
+ * device has been physically removed.
+ *
+ * In both cases, if the reference count equals zero, the corresponding
+ * reference count entry will be freed. The reference count entry must not be
+ * used any more after a call to this function.
  *
  * Also checks if the flags used for disabling the event match the flags used
  * for enabling the event and warns if they do not (regardless of reference
@@ -2223,7 +2233,7 @@ static int ssam_nf_refcount_enable(struct ssam_controller *ctrl,
  * returns the status of the event-enable EC command.
  */
 static int ssam_nf_refcount_disable_free(struct ssam_controller *ctrl,
-					 struct ssam_nf_refcount_entry *entry, u8 flags)
+					 struct ssam_nf_refcount_entry *entry, u8 flags, bool ec)
 {
 	const struct ssam_event_registry reg = entry->key.reg;
 	const struct ssam_event_id id = entry->key.id;
@@ -2232,8 +2242,9 @@ static int ssam_nf_refcount_disable_free(struct ssam_controller *ctrl,
 
 	lockdep_assert_held(&nf->lock);
 
-	ssam_dbg(ctrl, "disabling event (reg: %#04x, tc: %#04x, iid: %#04x, rc: %d)\n",
-		 reg.target_category, id.target_category, id.instance, entry->refcount);
+	ssam_dbg(ctrl, "%s event (reg: %#04x, tc: %#04x, iid: %#04x, rc: %d)\n",
+		 ec ? "disabling" : "detaching", reg.target_category, id.target_category,
+		 id.instance, entry->refcount);
 
 	if (entry->flags != flags) {
 		ssam_warn(ctrl,
@@ -2242,7 +2253,7 @@ static int ssam_nf_refcount_disable_free(struct ssam_controller *ctrl,
 			  id.instance);
 	}
 
-	if (entry->refcount == 0) {
+	if (ec && entry->refcount == 0) {
 		status = ssam_ssh_event_disable(ctrl, reg, id, flags);
 		kfree(entry);
 	}
@@ -2322,20 +2333,26 @@ int ssam_notifier_register(struct ssam_controller *ctrl, struct ssam_event_notif
 EXPORT_SYMBOL_GPL(ssam_notifier_register);
 
 /**
- * ssam_notifier_unregister() - Unregister an event notifier.
- * @ctrl: The controller the notifier has been registered on.
- * @n:    The event notifier to unregister.
+ * __ssam_notifier_unregister() - Unregister an event notifier.
+ * @ctrl:    The controller the notifier has been registered on.
+ * @n:       The event notifier to unregister.
+ * @disable: Whether to disable the corresponding event on the EC.
  *
  * Unregister an event notifier. Decrement the usage counter of the associated
  * SAM event if the notifier is not marked as an observer. If the usage counter
- * reaches zero, the event will be disabled.
+ * reaches zero and ``disable`` equals ``true``, the event will be disabled.
+ *
+ * Useful for hot-removable devices, where communication may fail once the
+ * device has been physically removed. In that case, specifying ``disable`` as
+ * ``false`` avoids communication with the EC.
  *
  * Return: Returns zero on success, %-ENOENT if the given notifier block has
  * not been registered on the controller. If the given notifier block was the
  * last one associated with its specific event, returns the status of the
  * event-disable EC-command.
  */
-int ssam_notifier_unregister(struct ssam_controller *ctrl, struct ssam_event_notifier *n)
+int __ssam_notifier_unregister(struct ssam_controller *ctrl, struct ssam_event_notifier *n,
+			       bool disable)
 {
 	u16 rqid = ssh_tc_to_rqid(n->event.id.target_category);
 	struct ssam_nf_refcount_entry *entry;
@@ -2373,7 +2390,7 @@ int ssam_notifier_unregister(struct ssam_controller *ctrl, struct ssam_event_not
 			goto remove;
 		}
 
-		status = ssam_nf_refcount_disable_free(ctrl, entry, n->event.flags);
+		status = ssam_nf_refcount_disable_free(ctrl, entry, n->event.flags, disable);
 	}
 
 remove:
@@ -2383,7 +2400,7 @@ int ssam_notifier_unregister(struct ssam_controller *ctrl, struct ssam_event_not
 
 	return status;
 }
-EXPORT_SYMBOL_GPL(ssam_notifier_unregister);
+EXPORT_SYMBOL_GPL(__ssam_notifier_unregister);
 
 /**
  * ssam_controller_event_enable() - Enable the specified event.
@@ -2477,7 +2494,7 @@ int ssam_controller_event_disable(struct ssam_controller *ctrl,
 		return -ENOENT;
 	}
 
-	status = ssam_nf_refcount_disable_free(ctrl, entry, flags);
+	status = ssam_nf_refcount_disable_free(ctrl, entry, flags, true);
 
 	mutex_unlock(&nf->lock);
 	return status;
diff --git a/include/linux/surface_aggregator/controller.h b/include/linux/surface_aggregator/controller.h
index 74bfdffaf7b0..50a2b4926c06 100644
--- a/include/linux/surface_aggregator/controller.h
+++ b/include/linux/surface_aggregator/controller.h
@@ -835,8 +835,28 @@ struct ssam_event_notifier {
 int ssam_notifier_register(struct ssam_controller *ctrl,
 			   struct ssam_event_notifier *n);
 
-int ssam_notifier_unregister(struct ssam_controller *ctrl,
-			     struct ssam_event_notifier *n);
+int __ssam_notifier_unregister(struct ssam_controller *ctrl,
+			       struct ssam_event_notifier *n, bool disable);
+
+/**
+ * ssam_notifier_unregister() - Unregister an event notifier.
+ * @ctrl:    The controller the notifier has been registered on.
+ * @n:       The event notifier to unregister.
+ *
+ * Unregister an event notifier. Decrement the usage counter of the associated
+ * SAM event if the notifier is not marked as an observer. If the usage counter
+ * reaches zero, the event will be disabled.
+ *
+ * Return: Returns zero on success, %-ENOENT if the given notifier block has
+ * not been registered on the controller. If the given notifier block was the
+ * last one associated with its specific event, returns the status of the
+ * event-disable EC-command.
+ */
+static inline int ssam_notifier_unregister(struct ssam_controller *ctrl,
+					   struct ssam_event_notifier *n)
+{
+	return __ssam_notifier_unregister(ctrl, n, true);
+}
 
 int ssam_controller_event_enable(struct ssam_controller *ctrl,
 				 struct ssam_event_registry reg,
diff --git a/include/linux/surface_aggregator/device.h b/include/linux/surface_aggregator/device.h
index 6df7c8d4e50e..c418f7f2732d 100644
--- a/include/linux/surface_aggregator/device.h
+++ b/include/linux/surface_aggregator/device.h
@@ -483,4 +483,70 @@ static inline void ssam_remove_clients(struct device *dev) {}
 				    sdev->uid.instance, ret);		\
 	}
 
+
+/* -- Helpers for client-device notifiers. ---------------------------------- */
+
+/**
+ * ssam_device_notifier_register() - Register an event notifier for the
+ * specified client device.
+ * @sdev: The device the notifier should be registered on.
+ * @n:    The event notifier to register.
+ *
+ * Register an event notifier. Increment the usage counter of the associated
+ * SAM event if the notifier is not marked as an observer. If the event is not
+ * marked as an observer and is currently not enabled, it will be enabled
+ * during this call. If the notifier is marked as an observer, no attempt will
+ * be made at enabling any event and no reference count will be modified.
+ *
+ * Notifiers marked as observers do not need to be associated with one specific
+ * event, i.e. as long as no event matching is performed, only the event target
+ * category needs to be set.
+ *
+ * Return: Returns zero on success, %-ENOSPC if there have already been
+ * %INT_MAX notifiers for the event ID/type associated with the notifier block
+ * registered, %-ENOMEM if the corresponding event entry could not be
+ * allocated, %-ENODEV if the device is marked as hot-removed. If this is the
+ * first time that a notifier block is registered for the specific associated
+ * event, returns the status of the event-enable EC-command.
+ */
+static inline int ssam_device_notifier_register(struct ssam_device *sdev,
+						struct ssam_event_notifier *n)
+{
+	/*
+	 * Note that this check does not provide any guarantees whatsoever as
+	 * hot-removal could happen at any point and we can't protect against
+	 * it. Nevertheless, if we can detect hot-removal, bail early to avoid
+	 * communication timeouts.
+	 */
+	if (ssam_device_is_hot_removed(sdev))
+		return -ENODEV;
+
+	return ssam_notifier_register(sdev->ctrl, n);
+}
+
+/**
+ * ssam_device_notifier_unregister() - Unregister an event notifier for the
+ * specified client device.
+ * @sdev: The device the notifier has been registered on.
+ * @n:    The event notifier to unregister.
+ *
+ * Unregister an event notifier. Decrement the usage counter of the associated
+ * SAM event if the notifier is not marked as an observer. If the usage counter
+ * reaches zero, the event will be disabled.
+ *
+ * In case the device has been marked as hot-removed, the event will not be
+ * disabled on the EC, as in those cases any attempt at doing so may time out.
+ *
+ * Return: Returns zero on success, %-ENOENT if the given notifier block has
+ * not been registered on the controller. If the given notifier block was the
+ * last one associated with its specific event, returns the status of the
+ * event-disable EC-command.
+ */
+static inline int ssam_device_notifier_unregister(struct ssam_device *sdev,
+						  struct ssam_event_notifier *n)
+{
+	return __ssam_notifier_unregister(sdev->ctrl, n,
+					  !ssam_device_is_hot_removed(sdev));
+}
+
 #endif /* _LINUX_SURFACE_AGGREGATOR_DEVICE_H */
-- 
2.38.0

From 0fd3d44ee0d9f061a61a909a0cc3fea3c61d40f0 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 27 May 2022 04:34:39 +0200
Subject: [PATCH] platform/surface: aggregator_registry: Use client device
 wrappers for notifier registration

Use newly introduced client device wrapper functions for notifier
registration and unregistration.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220527023447.2460025-5-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 drivers/platform/surface/surface_aggregator_registry.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 08019c6ccc9c..71fe014d3ebb 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -468,7 +468,7 @@ static int ssam_base_hub_probe(struct ssam_device *sdev)
 
 	ssam_device_set_drvdata(sdev, hub);
 
-	status = ssam_notifier_register(sdev->ctrl, &hub->notif);
+	status = ssam_device_notifier_register(sdev, &hub->notif);
 	if (status)
 		return status;
 
@@ -480,7 +480,7 @@ static int ssam_base_hub_probe(struct ssam_device *sdev)
 	return 0;
 
 err:
-	ssam_notifier_unregister(sdev->ctrl, &hub->notif);
+	ssam_device_notifier_unregister(sdev, &hub->notif);
 	cancel_delayed_work_sync(&hub->update_work);
 	ssam_remove_clients(&sdev->dev);
 	return status;
@@ -492,7 +492,7 @@ static void ssam_base_hub_remove(struct ssam_device *sdev)
 
 	sysfs_remove_group(&sdev->dev.kobj, &ssam_base_hub_group);
 
-	ssam_notifier_unregister(sdev->ctrl, &hub->notif);
+	ssam_device_notifier_unregister(sdev, &hub->notif);
 	cancel_delayed_work_sync(&hub->update_work);
 	ssam_remove_clients(&sdev->dev);
 }
-- 
2.38.0

From cf13eafc909feea8e97fbd414e0b699c5a42dca5 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 27 May 2022 04:34:40 +0200
Subject: [PATCH] power/supply: surface_charger: Use client device wrappers for
 notifier registration

Use newly introduced client device wrapper functions for notifier
registration and unregistration.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://lore.kernel.org/r/20220527023447.2460025-6-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 drivers/power/supply/surface_charger.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/power/supply/surface_charger.c b/drivers/power/supply/surface_charger.c
index a060c36c7766..59182d55742d 100644
--- a/drivers/power/supply/surface_charger.c
+++ b/drivers/power/supply/surface_charger.c
@@ -216,7 +216,7 @@ static int spwr_ac_register(struct spwr_ac_device *ac)
 	if (IS_ERR(ac->psy))
 		return PTR_ERR(ac->psy);
 
-	return ssam_notifier_register(ac->sdev->ctrl, &ac->notif);
+	return ssam_device_notifier_register(ac->sdev, &ac->notif);
 }
 
 
@@ -251,7 +251,7 @@ static void surface_ac_remove(struct ssam_device *sdev)
 {
 	struct spwr_ac_device *ac = ssam_device_get_drvdata(sdev);
 
-	ssam_notifier_unregister(sdev->ctrl, &ac->notif);
+	ssam_device_notifier_unregister(sdev, &ac->notif);
 }
 
 static const struct spwr_psy_properties spwr_psy_props_adp1 = {
-- 
2.38.0

From dc06c3418aa297013312a182d4c34da6609ce6de Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 27 May 2022 04:34:41 +0200
Subject: [PATCH] power/supply: surface_battery: Use client device wrappers for
 notifier registration

Use newly introduced client device wrapper functions for notifier
registration and unregistration.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://lore.kernel.org/r/20220527023447.2460025-7-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 drivers/power/supply/surface_battery.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/power/supply/surface_battery.c b/drivers/power/supply/surface_battery.c
index 5ec2e6bb2465..540707882bb0 100644
--- a/drivers/power/supply/surface_battery.c
+++ b/drivers/power/supply/surface_battery.c
@@ -802,7 +802,7 @@ static int spwr_battery_register(struct spwr_battery_device *bat)
 	if (IS_ERR(bat->psy))
 		return PTR_ERR(bat->psy);
 
-	return ssam_notifier_register(bat->sdev->ctrl, &bat->notif);
+	return ssam_device_notifier_register(bat->sdev, &bat->notif);
 }
 
 
@@ -837,7 +837,7 @@ static void surface_battery_remove(struct ssam_device *sdev)
 {
 	struct spwr_battery_device *bat = ssam_device_get_drvdata(sdev);
 
-	ssam_notifier_unregister(sdev->ctrl, &bat->notif);
+	ssam_device_notifier_unregister(sdev, &bat->notif);
 	cancel_delayed_work_sync(&bat->update_work);
 }
 
-- 
2.38.0

From 900fd067b67e27666f43785ef0268e2c1b131eea Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 27 May 2022 04:34:42 +0200
Subject: [PATCH] HID: surface-hid: Add support for hot-removal

Add support for hot-removal of SSAM HID client devices.

Once a device has been hot-removed, further communication with it should
be avoided as it may fail and time out. While the device will be removed
as soon as we detect hot-removal, communication may still occur during
teardown, especially when unregistering notifiers.

While hot-removal is a surprise event that can happen at any time, try
to avoid communication as much as possible once it has been detected to
prevent timeouts that can slow down device removal and cause issues,
e.g. when quickly re-attaching the device.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220527023447.2460025-8-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 drivers/hid/surface-hid/surface_hid_core.c | 38 +++++++++++++++++++++-
 1 file changed, 37 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/surface-hid/surface_hid_core.c b/drivers/hid/surface-hid/surface_hid_core.c
index e46330b2e561..87637f813de2 100644
--- a/drivers/hid/surface-hid/surface_hid_core.c
+++ b/drivers/hid/surface-hid/surface_hid_core.c
@@ -19,12 +19,30 @@
 #include "surface_hid_core.h"
 
 
+/* -- Utility functions. ---------------------------------------------------- */
+
+static bool surface_hid_is_hot_removed(struct surface_hid_device *shid)
+{
+	/*
+	 * Non-ssam client devices, i.e. platform client devices, cannot be
+	 * hot-removed.
+	 */
+	if (!is_ssam_device(shid->dev))
+		return false;
+
+	return ssam_device_is_hot_removed(to_ssam_device(shid->dev));
+}
+
+
 /* -- Device descriptor access. --------------------------------------------- */
 
 static int surface_hid_load_hid_descriptor(struct surface_hid_device *shid)
 {
 	int status;
 
+	if (surface_hid_is_hot_removed(shid))
+		return -ENODEV;
+
 	status = shid->ops.get_descriptor(shid, SURFACE_HID_DESC_HID,
 			(u8 *)&shid->hid_desc, sizeof(shid->hid_desc));
 	if (status)
@@ -61,6 +79,9 @@ static int surface_hid_load_device_attributes(struct surface_hid_device *shid)
 {
 	int status;
 
+	if (surface_hid_is_hot_removed(shid))
+		return -ENODEV;
+
 	status = shid->ops.get_descriptor(shid, SURFACE_HID_DESC_ATTRS,
 			(u8 *)&shid->attrs, sizeof(shid->attrs));
 	if (status)
@@ -88,9 +109,18 @@ static int surface_hid_start(struct hid_device *hid)
 static void surface_hid_stop(struct hid_device *hid)
 {
 	struct surface_hid_device *shid = hid->driver_data;
+	bool hot_removed;
+
+	/*
+	 * Communication may fail for devices that have been hot-removed. This
+	 * also includes unregistration of HID events, so we need to check this
+	 * here. Only if the device has not been marked as hot-removed, we can
+	 * safely disable events.
+	 */
+	hot_removed = surface_hid_is_hot_removed(shid);
 
 	/* Note: This call will log errors for us, so ignore them here. */
-	ssam_notifier_unregister(shid->ctrl, &shid->notif);
+	__ssam_notifier_unregister(shid->ctrl, &shid->notif, !hot_removed);
 }
 
 static int surface_hid_open(struct hid_device *hid)
@@ -109,6 +139,9 @@ static int surface_hid_parse(struct hid_device *hid)
 	u8 *buf;
 	int status;
 
+	if (surface_hid_is_hot_removed(shid))
+		return -ENODEV;
+
 	buf = kzalloc(len, GFP_KERNEL);
 	if (!buf)
 		return -ENOMEM;
@@ -126,6 +159,9 @@ static int surface_hid_raw_request(struct hid_device *hid, unsigned char reportn
 {
 	struct surface_hid_device *shid = hid->driver_data;
 
+	if (surface_hid_is_hot_removed(shid))
+		return -ENODEV;
+
 	if (rtype == HID_OUTPUT_REPORT && reqtype == HID_REQ_SET_REPORT)
 		return shid->ops.output_report(shid, reportnum, buf, len);
 
-- 
2.38.0

From 6b145011e2842f8c0bfd947283ac2183f113604c Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 27 May 2022 04:34:43 +0200
Subject: [PATCH] platform/surface: aggregator: Add comment for KIP subsystem
 category

The KIP subsystem (full name unknown, abbreviation has been obtained
through reverse engineering) handles detachable peripherals such as the
keyboard cover on the Surface Pro X and Surface Pro 8.

It is currently not entirely clear what this subsystem entails, but at
the very least it provides event notifications for when the keyboard
cover on the Surface Pro X and Surface Pro 8 have been detached or
re-attached, as well as the state that the keyboard cover is currently
in (e.g. folded-back, folded laptop-like, closed, etc.).

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220527023447.2460025-9-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 include/linux/surface_aggregator/serial_hub.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/surface_aggregator/serial_hub.h b/include/linux/surface_aggregator/serial_hub.h
index c3de43edcffa..26b95ec12733 100644
--- a/include/linux/surface_aggregator/serial_hub.h
+++ b/include/linux/surface_aggregator/serial_hub.h
@@ -306,7 +306,7 @@ enum ssam_ssh_tc {
 	SSAM_SSH_TC_LPC = 0x0b,
 	SSAM_SSH_TC_TCL = 0x0c,
 	SSAM_SSH_TC_SFL = 0x0d,
-	SSAM_SSH_TC_KIP = 0x0e,
+	SSAM_SSH_TC_KIP = 0x0e,	/* Manages detachable peripherals (Pro X/8 keyboard cover) */
 	SSAM_SSH_TC_EXT = 0x0f,
 	SSAM_SSH_TC_BLD = 0x10,
 	SSAM_SSH_TC_BAS = 0x11,	/* Detachment system (Surface Book 2/3). */
-- 
2.38.0

From 9767e9af49e71d638777210bdbbb1a6ec83c00bf Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 27 May 2022 04:34:44 +0200
Subject: [PATCH] platform/surface: aggregator_registry: Generify subsystem hub
 functionality

The Surface System Aggregator Module (SSAM) has multiple subsystems that
can manage detachable devices. At the moment, we only support the "base"
(BAS/0x11) subsystem, which is used on the Surface Book 3 to manage
devices (including keyboard, touchpad, and secondary battery) connected
to the base of the device.

The Surface Pro 8 has a new type-cover with keyboard and touchpad, which
is managed via the KIP/0x0e subsystem. The general procedure is the
same, but with slightly different events and setup. To make
implementation of the KIP hub easier and prevent duplication, generify
the parts of the base hub that we can use for the KIP hub (or any
potential future subsystem hubs).

This also switches over to use the newly introduced "hot-remove"
functionality, which should prevent communication issues when devices
have been detached.

Lastly, also drop the undocumented and unused sysfs "state" attribute of
the base hub. It has at best been useful for debugging.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220527023447.2460025-10-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 .../surface/surface_aggregator_registry.c     | 269 ++++++++++--------
 1 file changed, 153 insertions(+), 116 deletions(-)

diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 71fe014d3ebb..0b1ca1155770 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -308,30 +308,159 @@ static int ssam_hub_register_clients(struct device *parent, struct ssam_controll
 }
 
 
-/* -- SSAM base-hub driver. ------------------------------------------------- */
+/* -- SSAM generic subsystem hub driver framework. -------------------------- */
 
-/*
- * Some devices (especially battery) may need a bit of time to be fully usable
- * after being (re-)connected. This delay has been determined via
- * experimentation.
- */
-#define SSAM_BASE_UPDATE_CONNECT_DELAY		msecs_to_jiffies(2500)
+enum ssam_hub_state {
+	SSAM_HUB_UNINITIALIZED,		/* Only set during initialization. */
+	SSAM_HUB_CONNECTED,
+	SSAM_HUB_DISCONNECTED,
+};
 
-enum ssam_base_hub_state {
-	SSAM_BASE_HUB_UNINITIALIZED,
-	SSAM_BASE_HUB_CONNECTED,
-	SSAM_BASE_HUB_DISCONNECTED,
+enum ssam_hub_flags {
+	SSAM_HUB_HOT_REMOVED,
 };
 
-struct ssam_base_hub {
+struct ssam_hub {
 	struct ssam_device *sdev;
 
-	enum ssam_base_hub_state state;
+	enum ssam_hub_state state;
+	unsigned long flags;
+
 	struct delayed_work update_work;
+	unsigned long connect_delay;
 
 	struct ssam_event_notifier notif;
+
+	int (*get_state)(struct ssam_hub *hub, enum ssam_hub_state *state);
 };
 
+static void ssam_hub_update_workfn(struct work_struct *work)
+{
+	struct ssam_hub *hub = container_of(work, struct ssam_hub, update_work.work);
+	struct fwnode_handle *node = dev_fwnode(&hub->sdev->dev);
+	enum ssam_hub_state state;
+	int status = 0;
+
+	status = hub->get_state(hub, &state);
+	if (status)
+		return;
+
+	/*
+	 * There is a small possibility that hub devices were hot-removed and
+	 * re-added before we were able to remove them here. In that case, both
+	 * the state returned by get_state() and the state of the hub will
+	 * equal SSAM_HUB_CONNECTED and we would bail early below, which would
+	 * leave child devices without proper (re-)initialization and the
+	 * hot-remove flag set.
+	 *
+	 * Therefore, we check whether devices have been hot-removed via an
+	 * additional flag on the hub and, in this case, override the returned
+	 * hub state. In case of a missed disconnect (i.e. get_state returned
+	 * "connected"), we further need to re-schedule this work (with the
+	 * appropriate delay) as the actual connect work submission might have
+	 * been merged with this one.
+	 *
+	 * This then leads to one of two cases: Either we submit an unnecessary
+	 * work item (which will get ignored via either the queue or the state
+	 * checks) or, in the unlikely case that the work is actually required,
+	 * double the normal connect delay.
+	 */
+	if (test_and_clear_bit(SSAM_HUB_HOT_REMOVED, &hub->flags)) {
+		if (state == SSAM_HUB_CONNECTED)
+			schedule_delayed_work(&hub->update_work, hub->connect_delay);
+
+		state = SSAM_HUB_DISCONNECTED;
+	}
+
+	if (hub->state == state)
+		return;
+	hub->state = state;
+
+	if (hub->state == SSAM_HUB_CONNECTED)
+		status = ssam_hub_register_clients(&hub->sdev->dev, hub->sdev->ctrl, node);
+	else
+		ssam_remove_clients(&hub->sdev->dev);
+
+	if (status)
+		dev_err(&hub->sdev->dev, "failed to update hub child devices: %d\n", status);
+}
+
+static int ssam_hub_mark_hot_removed(struct device *dev, void *_data)
+{
+	struct ssam_device *sdev = to_ssam_device(dev);
+
+	if (is_ssam_device(dev))
+		ssam_device_mark_hot_removed(sdev);
+
+	return 0;
+}
+
+static void ssam_hub_update(struct ssam_hub *hub, bool connected)
+{
+	unsigned long delay;
+
+	/* Mark devices as hot-removed before we remove any. */
+	if (!connected) {
+		set_bit(SSAM_HUB_HOT_REMOVED, &hub->flags);
+		device_for_each_child_reverse(&hub->sdev->dev, NULL, ssam_hub_mark_hot_removed);
+	}
+
+	/*
+	 * Delay update when the base/keyboard cover is being connected to give
+	 * devices/EC some time to set up.
+	 */
+	delay = connected ? hub->connect_delay : 0;
+
+	schedule_delayed_work(&hub->update_work, delay);
+}
+
+static int __maybe_unused ssam_hub_resume(struct device *dev)
+{
+	struct ssam_hub *hub = dev_get_drvdata(dev);
+
+	schedule_delayed_work(&hub->update_work, 0);
+	return 0;
+}
+static SIMPLE_DEV_PM_OPS(ssam_hub_pm_ops, NULL, ssam_hub_resume);
+
+static int ssam_hub_setup(struct ssam_device *sdev, struct ssam_hub *hub)
+{
+	int status;
+
+	hub->sdev = sdev;
+	hub->state = SSAM_HUB_UNINITIALIZED;
+
+	INIT_DELAYED_WORK(&hub->update_work, ssam_hub_update_workfn);
+
+	ssam_device_set_drvdata(sdev, hub);
+
+	status = ssam_device_notifier_register(sdev, &hub->notif);
+	if (status)
+		return status;
+
+	schedule_delayed_work(&hub->update_work, 0);
+	return 0;
+}
+
+static void ssam_hub_remove(struct ssam_device *sdev)
+{
+	struct ssam_hub *hub = ssam_device_get_drvdata(sdev);
+
+	ssam_device_notifier_unregister(sdev, &hub->notif);
+	cancel_delayed_work_sync(&hub->update_work);
+	ssam_remove_clients(&sdev->dev);
+}
+
+
+/* -- SSAM base-hub driver. ------------------------------------------------- */
+
+/*
+ * Some devices (especially battery) may need a bit of time to be fully usable
+ * after being (re-)connected. This delay has been determined via
+ * experimentation.
+ */
+#define SSAM_BASE_UPDATE_CONNECT_DELAY		msecs_to_jiffies(2500)
+
 SSAM_DEFINE_SYNC_REQUEST_R(ssam_bas_query_opmode, u8, {
 	.target_category = SSAM_SSH_TC_BAS,
 	.target_id       = 0x01,
@@ -342,7 +471,7 @@ SSAM_DEFINE_SYNC_REQUEST_R(ssam_bas_query_opmode, u8, {
 #define SSAM_BAS_OPMODE_TABLET		0x00
 #define SSAM_EVENT_BAS_CID_CONNECTION	0x0c
 
-static int ssam_base_hub_query_state(struct ssam_base_hub *hub, enum ssam_base_hub_state *state)
+static int ssam_base_hub_query_state(struct ssam_hub *hub, enum ssam_hub_state *state)
 {
 	u8 opmode;
 	int status;
@@ -354,62 +483,16 @@ static int ssam_base_hub_query_state(struct ssam_base_hub *hub, enum ssam_base_h
 	}
 
 	if (opmode != SSAM_BAS_OPMODE_TABLET)
-		*state = SSAM_BASE_HUB_CONNECTED;
+		*state = SSAM_HUB_CONNECTED;
 	else
-		*state = SSAM_BASE_HUB_DISCONNECTED;
+		*state = SSAM_HUB_DISCONNECTED;
 
 	return 0;
 }
 
-static ssize_t ssam_base_hub_state_show(struct device *dev, struct device_attribute *attr,
-					char *buf)
-{
-	struct ssam_base_hub *hub = dev_get_drvdata(dev);
-	bool connected = hub->state == SSAM_BASE_HUB_CONNECTED;
-
-	return sysfs_emit(buf, "%d\n", connected);
-}
-
-static struct device_attribute ssam_base_hub_attr_state =
-	__ATTR(state, 0444, ssam_base_hub_state_show, NULL);
-
-static struct attribute *ssam_base_hub_attrs[] = {
-	&ssam_base_hub_attr_state.attr,
-	NULL,
-};
-
-static const struct attribute_group ssam_base_hub_group = {
-	.attrs = ssam_base_hub_attrs,
-};
-
-static void ssam_base_hub_update_workfn(struct work_struct *work)
-{
-	struct ssam_base_hub *hub = container_of(work, struct ssam_base_hub, update_work.work);
-	struct fwnode_handle *node = dev_fwnode(&hub->sdev->dev);
-	enum ssam_base_hub_state state;
-	int status = 0;
-
-	status = ssam_base_hub_query_state(hub, &state);
-	if (status)
-		return;
-
-	if (hub->state == state)
-		return;
-	hub->state = state;
-
-	if (hub->state == SSAM_BASE_HUB_CONNECTED)
-		status = ssam_hub_register_clients(&hub->sdev->dev, hub->sdev->ctrl, node);
-	else
-		ssam_remove_clients(&hub->sdev->dev);
-
-	if (status)
-		dev_err(&hub->sdev->dev, "failed to update base-hub devices: %d\n", status);
-}
-
 static u32 ssam_base_hub_notif(struct ssam_event_notifier *nf, const struct ssam_event *event)
 {
-	struct ssam_base_hub *hub = container_of(nf, struct ssam_base_hub, notif);
-	unsigned long delay;
+	struct ssam_hub *hub = container_of(nf, struct ssam_hub, notif);
 
 	if (event->command_id != SSAM_EVENT_BAS_CID_CONNECTION)
 		return 0;
@@ -419,13 +502,7 @@ static u32 ssam_base_hub_notif(struct ssam_event_notifier *nf, const struct ssam
 		return 0;
 	}
 
-	/*
-	 * Delay update when the base is being connected to give devices/EC
-	 * some time to set up.
-	 */
-	delay = event->data[0] ? SSAM_BASE_UPDATE_CONNECT_DELAY : 0;
-
-	schedule_delayed_work(&hub->update_work, delay);
+	ssam_hub_update(hub, event->data[0]);
 
 	/*
 	 * Do not return SSAM_NOTIF_HANDLED: The event should be picked up and
@@ -435,27 +512,14 @@ static u32 ssam_base_hub_notif(struct ssam_event_notifier *nf, const struct ssam
 	return 0;
 }
 
-static int __maybe_unused ssam_base_hub_resume(struct device *dev)
-{
-	struct ssam_base_hub *hub = dev_get_drvdata(dev);
-
-	schedule_delayed_work(&hub->update_work, 0);
-	return 0;
-}
-static SIMPLE_DEV_PM_OPS(ssam_base_hub_pm_ops, NULL, ssam_base_hub_resume);
-
 static int ssam_base_hub_probe(struct ssam_device *sdev)
 {
-	struct ssam_base_hub *hub;
-	int status;
+	struct ssam_hub *hub;
 
 	hub = devm_kzalloc(&sdev->dev, sizeof(*hub), GFP_KERNEL);
 	if (!hub)
 		return -ENOMEM;
 
-	hub->sdev = sdev;
-	hub->state = SSAM_BASE_HUB_UNINITIALIZED;
-
 	hub->notif.base.priority = INT_MAX;  /* This notifier should run first. */
 	hub->notif.base.fn = ssam_base_hub_notif;
 	hub->notif.event.reg = SSAM_EVENT_REGISTRY_SAM;
@@ -464,37 +528,10 @@ static int ssam_base_hub_probe(struct ssam_device *sdev)
 	hub->notif.event.mask = SSAM_EVENT_MASK_NONE;
 	hub->notif.event.flags = SSAM_EVENT_SEQUENCED;
 
-	INIT_DELAYED_WORK(&hub->update_work, ssam_base_hub_update_workfn);
-
-	ssam_device_set_drvdata(sdev, hub);
-
-	status = ssam_device_notifier_register(sdev, &hub->notif);
-	if (status)
-		return status;
-
-	status = sysfs_create_group(&sdev->dev.kobj, &ssam_base_hub_group);
-	if (status)
-		goto err;
-
-	schedule_delayed_work(&hub->update_work, 0);
-	return 0;
+	hub->connect_delay = SSAM_BASE_UPDATE_CONNECT_DELAY;
+	hub->get_state = ssam_base_hub_query_state;
 
-err:
-	ssam_device_notifier_unregister(sdev, &hub->notif);
-	cancel_delayed_work_sync(&hub->update_work);
-	ssam_remove_clients(&sdev->dev);
-	return status;
-}
-
-static void ssam_base_hub_remove(struct ssam_device *sdev)
-{
-	struct ssam_base_hub *hub = ssam_device_get_drvdata(sdev);
-
-	sysfs_remove_group(&sdev->dev.kobj, &ssam_base_hub_group);
-
-	ssam_device_notifier_unregister(sdev, &hub->notif);
-	cancel_delayed_work_sync(&hub->update_work);
-	ssam_remove_clients(&sdev->dev);
+	return ssam_hub_setup(sdev, hub);
 }
 
 static const struct ssam_device_id ssam_base_hub_match[] = {
@@ -504,12 +541,12 @@ static const struct ssam_device_id ssam_base_hub_match[] = {
 
 static struct ssam_device_driver ssam_base_hub_driver = {
 	.probe = ssam_base_hub_probe,
-	.remove = ssam_base_hub_remove,
+	.remove = ssam_hub_remove,
 	.match_table = ssam_base_hub_match,
 	.driver = {
 		.name = "surface_aggregator_base_hub",
 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
-		.pm = &ssam_base_hub_pm_ops,
+		.pm = &ssam_hub_pm_ops,
 	},
 };
 
-- 
2.38.0

From e668d006ec6ad044f993c0857afee7f3f0303709 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 27 May 2022 04:34:45 +0200
Subject: [PATCH] platform/surface: aggregator_registry: Change device ID for
 base hub

Use the target category of the (base) hub as instance id in the
(virtual) hub device UID. This makes association of the hub with the
respective subsystem easier.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220527023447.2460025-11-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 drivers/platform/surface/surface_aggregator_registry.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 0b1ca1155770..d0e9e287c7e5 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -43,7 +43,7 @@ static const struct software_node ssam_node_root = {
 
 /* Base device hub (devices attached to Surface Book 3 base). */
 static const struct software_node ssam_node_hub_base = {
-	.name = "ssam:00:00:02:00:00",
+	.name = "ssam:00:00:02:11:00",
 	.parent = &ssam_node_root,
 };
 
@@ -535,7 +535,7 @@ static int ssam_base_hub_probe(struct ssam_device *sdev)
 }
 
 static const struct ssam_device_id ssam_base_hub_match[] = {
-	{ SSAM_VDEV(HUB, 0x02, SSAM_ANY_IID, 0x00) },
+	{ SSAM_VDEV(HUB, 0x02, SSAM_SSH_TC_BAS, 0x00) },
 	{ },
 };
 
-- 
2.38.0

From 607f5c3e825c05bf0a5b9fa2e9570bc01cef2770 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 27 May 2022 04:34:46 +0200
Subject: [PATCH] platform/surface: aggregator_registry: Add KIP device hub

Add a Surface System Aggregator Module (SSAM) client device hub for
hot-removable devices managed via the KIP subsystem.

The KIP subsystem (full name unknown, abbreviation has been obtained
through reverse engineering) is a subsystem that manages hot-removable
SSAM client devices. Specifically, it manages HID input devices
contained in the detachable keyboard cover of the Surface Pro 8 and
Surface Pro X.

The KIP subsystem handles a single group of devices (e.g. all devices
contained in the keyboard cover) and cannot handle devices individually.
Thus we model it as a client device hub, which (hot-)removes all devices
contained under it once removal of the hub (e.g. keyboard cover) has
been detected and (re-)adds all devices once the physical hub device has
been (re-)attached. To do this, use the previously generified SSAM
subsystem hub framework.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220527023447.2460025-12-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 .../surface/surface_aggregator_registry.c     | 103 +++++++++++++++++-
 1 file changed, 101 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index d0e9e287c7e5..0b4aeba4ad93 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -551,6 +551,93 @@ static struct ssam_device_driver ssam_base_hub_driver = {
 };
 
 
+/* -- SSAM KIP-subsystem hub driver. ---------------------------------------- */
+
+/*
+ * Some devices may need a bit of time to be fully usable after being
+ * (re-)connected. This delay has been determined via experimentation.
+ */
+#define SSAM_KIP_UPDATE_CONNECT_DELAY		msecs_to_jiffies(250)
+
+#define SSAM_EVENT_KIP_CID_CONNECTION		0x2c
+
+SSAM_DEFINE_SYNC_REQUEST_R(__ssam_kip_get_connection_state, u8, {
+	.target_category = SSAM_SSH_TC_KIP,
+	.target_id       = 0x01,
+	.command_id      = 0x2c,
+	.instance_id     = 0x00,
+});
+
+static int ssam_kip_get_connection_state(struct ssam_hub *hub, enum ssam_hub_state *state)
+{
+	int status;
+	u8 connected;
+
+	status = ssam_retry(__ssam_kip_get_connection_state, hub->sdev->ctrl, &connected);
+	if (status < 0) {
+		dev_err(&hub->sdev->dev, "failed to query KIP connection state: %d\n", status);
+		return status;
+	}
+
+	*state = connected ? SSAM_HUB_CONNECTED : SSAM_HUB_DISCONNECTED;
+	return 0;
+}
+
+static u32 ssam_kip_hub_notif(struct ssam_event_notifier *nf, const struct ssam_event *event)
+{
+	struct ssam_hub *hub = container_of(nf, struct ssam_hub, notif);
+
+	if (event->command_id != SSAM_EVENT_KIP_CID_CONNECTION)
+		return 0;	/* Return "unhandled". */
+
+	if (event->length < 1) {
+		dev_err(&hub->sdev->dev, "unexpected payload size: %u\n", event->length);
+		return 0;
+	}
+
+	ssam_hub_update(hub, event->data[0]);
+	return SSAM_NOTIF_HANDLED;
+}
+
+static int ssam_kip_hub_probe(struct ssam_device *sdev)
+{
+	struct ssam_hub *hub;
+
+	hub = devm_kzalloc(&sdev->dev, sizeof(*hub), GFP_KERNEL);
+	if (!hub)
+		return -ENOMEM;
+
+	hub->notif.base.priority = INT_MAX;  /* This notifier should run first. */
+	hub->notif.base.fn = ssam_kip_hub_notif;
+	hub->notif.event.reg = SSAM_EVENT_REGISTRY_SAM;
+	hub->notif.event.id.target_category = SSAM_SSH_TC_KIP,
+	hub->notif.event.id.instance = 0,
+	hub->notif.event.mask = SSAM_EVENT_MASK_TARGET;
+	hub->notif.event.flags = SSAM_EVENT_SEQUENCED;
+
+	hub->connect_delay = SSAM_KIP_UPDATE_CONNECT_DELAY;
+	hub->get_state = ssam_kip_get_connection_state;
+
+	return ssam_hub_setup(sdev, hub);
+}
+
+static const struct ssam_device_id ssam_kip_hub_match[] = {
+	{ SSAM_VDEV(HUB, 0x01, SSAM_SSH_TC_KIP, 0x00) },
+	{ },
+};
+
+static struct ssam_device_driver ssam_kip_hub_driver = {
+	.probe = ssam_kip_hub_probe,
+	.remove = ssam_hub_remove,
+	.match_table = ssam_kip_hub_match,
+	.driver = {
+		.name = "surface_kip_hub",
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+		.pm = &ssam_hub_pm_ops,
+	},
+};
+
+
 /* -- SSAM platform/meta-hub driver. ---------------------------------------- */
 
 static const struct acpi_device_id ssam_platform_hub_match[] = {
@@ -676,18 +763,30 @@ static int __init ssam_device_hub_init(void)
 
 	status = platform_driver_register(&ssam_platform_hub_driver);
 	if (status)
-		return status;
+		goto err_platform;
 
 	status = ssam_device_driver_register(&ssam_base_hub_driver);
 	if (status)
-		platform_driver_unregister(&ssam_platform_hub_driver);
+		goto err_base;
+
+	status = ssam_device_driver_register(&ssam_kip_hub_driver);
+	if (status)
+		goto err_kip;
 
+	return 0;
+
+err_kip:
+	ssam_device_driver_unregister(&ssam_base_hub_driver);
+err_base:
+	platform_driver_unregister(&ssam_platform_hub_driver);
+err_platform:
 	return status;
 }
 module_init(ssam_device_hub_init);
 
 static void __exit ssam_device_hub_exit(void)
 {
+	ssam_device_driver_unregister(&ssam_kip_hub_driver);
 	ssam_device_driver_unregister(&ssam_base_hub_driver);
 	platform_driver_unregister(&ssam_platform_hub_driver);
 }
-- 
2.38.0

From 336477e2e2926a4adea68881da5b10a4445c702b Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 27 May 2022 04:34:47 +0200
Subject: [PATCH] platform/surface: aggregator_registry: Add support for
 keyboard cover on Surface Pro 8

Add support for the detachable keyboard cover on the Surface Pro 8.

The keyboard cover on the Surface Pro 8 is, unlike the keyboard covers
of earlier Surface Pro generations, handled via the Surface System
Aggregator Module (SSAM). The keyboard and touchpad (as well as other
HID input devices) of this cover are standard SSAM HID client devices
(just like keyboard and touchpad on e.g. the Surface Laptop 3 and 4),
however, some care needs to be taken as they can be physically detached
(similarly to the Surface Book 3). Specifically, the respective SSAM
client devices need to be removed when the keyboard cover has been
detached and (re-)initialized when the keyboard cover has been
(re-)attached.

On the Surface Pro 8, detachment of the keyboard cover (and by extension
its devices) is managed via the KIP subsystem. Therefore, said devices
need to be registered under the KIP device hub, which in turn will
remove and re-create/re-initialize those devices as needed.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220527023447.2460025-13-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 .../surface/surface_aggregator_registry.c     | 37 ++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 0b4aeba4ad93..3b1310d61a24 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -41,6 +41,12 @@ static const struct software_node ssam_node_root = {
 	.name = "ssam_platform_hub",
 };
 
+/* KIP device hub (connects keyboard cover devices on Surface Pro 8). */
+static const struct software_node ssam_node_hub_kip = {
+	.name = "ssam:00:00:01:0e:00",
+	.parent = &ssam_node_root,
+};
+
 /* Base device hub (devices attached to Surface Book 3 base). */
 static const struct software_node ssam_node_hub_base = {
 	.name = "ssam:00:00:02:11:00",
@@ -155,6 +161,30 @@ static const struct software_node ssam_node_hid_base_iid6 = {
 	.parent = &ssam_node_hub_base,
 };
 
+/* HID keyboard (KIP hub). */
+static const struct software_node ssam_node_hid_kip_keyboard = {
+	.name = "ssam:01:15:02:01:00",
+	.parent = &ssam_node_hub_kip,
+};
+
+/* HID pen stash (KIP hub; pen taken / stashed away evens). */
+static const struct software_node ssam_node_hid_kip_penstash = {
+	.name = "ssam:01:15:02:02:00",
+	.parent = &ssam_node_hub_kip,
+};
+
+/* HID touchpad (KIP hub). */
+static const struct software_node ssam_node_hid_kip_touchpad = {
+	.name = "ssam:01:15:02:03:00",
+	.parent = &ssam_node_hub_kip,
+};
+
+/* HID device instance 5 (KIP hub, unknown HID device). */
+static const struct software_node ssam_node_hid_kip_iid5 = {
+	.name = "ssam:01:15:02:05:00",
+	.parent = &ssam_node_hub_kip,
+};
+
 /*
  * Devices for 5th- and 6th-generations models:
  * - Surface Book 2,
@@ -230,10 +260,15 @@ static const struct software_node *ssam_node_group_sp7[] = {
 
 static const struct software_node *ssam_node_group_sp8[] = {
 	&ssam_node_root,
+	&ssam_node_hub_kip,
 	&ssam_node_bat_ac,
 	&ssam_node_bat_main,
 	&ssam_node_tmp_pprof,
-	/* TODO: Add support for keyboard cover. */
+	&ssam_node_hid_kip_keyboard,
+	&ssam_node_hid_kip_penstash,
+	&ssam_node_hid_kip_touchpad,
+	&ssam_node_hid_kip_iid5,
+	/* TODO: Add support for tablet mode switch. */
 	NULL,
 };
 
-- 
2.38.0

From 6451a24698c042a26385615af15bc5bb97188d99 Mon Sep 17 00:00:00 2001
From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Date: Fri, 10 Jun 2022 14:41:58 +0900
Subject: [PATCH] platform/surface: avoid flush_scheduled_work() usage

Use local wq in order to avoid flush_scheduled_work() usage.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com>
Tested-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/63ec2d45-c67c-1134-f6d3-490c8ba67a01@I-love.SAKURA.ne.jp
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 .../platform/surface/surface_acpi_notify.c    | 27 ++++++++++++++++---
 1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/drivers/platform/surface/surface_acpi_notify.c b/drivers/platform/surface/surface_acpi_notify.c
index 7b758f8cc137..c0e12f0b9b79 100644
--- a/drivers/platform/surface/surface_acpi_notify.c
+++ b/drivers/platform/surface/surface_acpi_notify.c
@@ -37,6 +37,7 @@ struct san_data {
 #define to_san_data(ptr, member) \
 	container_of(ptr, struct san_data, member)
 
+static struct workqueue_struct *san_wq;
 
 /* -- dGPU notifier interface. ---------------------------------------------- */
 
@@ -356,7 +357,7 @@ static u32 san_evt_bat_nf(struct ssam_event_notifier *nf,
 
 	memcpy(&work->event, event, sizeof(struct ssam_event) + event->length);
 
-	schedule_delayed_work(&work->work, delay);
+	queue_delayed_work(san_wq, &work->work, delay);
 	return SSAM_NOTIF_HANDLED;
 }
 
@@ -861,7 +862,7 @@ static int san_remove(struct platform_device *pdev)
 	 * We have unregistered our event sources. Now we need to ensure that
 	 * all delayed works they may have spawned are run to completion.
 	 */
-	flush_scheduled_work();
+	flush_workqueue(san_wq);
 
 	return 0;
 }
@@ -881,7 +882,27 @@ static struct platform_driver surface_acpi_notify = {
 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
 	},
 };
-module_platform_driver(surface_acpi_notify);
+
+static int __init san_init(void)
+{
+	int ret;
+
+	san_wq = alloc_workqueue("san_wq", 0, 0);
+	if (!san_wq)
+		return -ENOMEM;
+	ret = platform_driver_register(&surface_acpi_notify);
+	if (ret)
+		destroy_workqueue(san_wq);
+	return ret;
+}
+module_init(san_init);
+
+static void __exit san_exit(void)
+{
+	platform_driver_unregister(&surface_acpi_notify);
+	destroy_workqueue(san_wq);
+}
+module_exit(san_exit);
 
 MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
 MODULE_DESCRIPTION("Surface ACPI Notify driver for Surface System Aggregator Module");
-- 
2.38.0

From d08092adbfe7e12c8fd688e2262ce7dad8f7baf4 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Tue, 14 Jun 2022 21:41:17 +0200
Subject: [PATCH] platform/surface: aggregator: Reserve more event- and
 target-categories

With the introduction of the Surface Laptop Studio, more event- and
target categories have been added. Therefore, increase the number of
reserved events and extend the enum of know target categories to
accommodate this.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220614194117.4118897-1-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 drivers/platform/surface/aggregator/trace.h   | 80 +++++++++++--------
 include/linux/surface_aggregator/serial_hub.h | 75 +++++++++--------
 2 files changed, 85 insertions(+), 70 deletions(-)

diff --git a/drivers/platform/surface/aggregator/trace.h b/drivers/platform/surface/aggregator/trace.h
index de64cf169060..cc9e73fbc18e 100644
--- a/drivers/platform/surface/aggregator/trace.h
+++ b/drivers/platform/surface/aggregator/trace.h
@@ -76,7 +76,7 @@ TRACE_DEFINE_ENUM(SSAM_SSH_TC_HID);
 TRACE_DEFINE_ENUM(SSAM_SSH_TC_TCH);
 TRACE_DEFINE_ENUM(SSAM_SSH_TC_BKL);
 TRACE_DEFINE_ENUM(SSAM_SSH_TC_TAM);
-TRACE_DEFINE_ENUM(SSAM_SSH_TC_ACC);
+TRACE_DEFINE_ENUM(SSAM_SSH_TC_ACC0);
 TRACE_DEFINE_ENUM(SSAM_SSH_TC_UFI);
 TRACE_DEFINE_ENUM(SSAM_SSH_TC_USC);
 TRACE_DEFINE_ENUM(SSAM_SSH_TC_PEN);
@@ -85,6 +85,11 @@ TRACE_DEFINE_ENUM(SSAM_SSH_TC_AUD);
 TRACE_DEFINE_ENUM(SSAM_SSH_TC_SMC);
 TRACE_DEFINE_ENUM(SSAM_SSH_TC_KPD);
 TRACE_DEFINE_ENUM(SSAM_SSH_TC_REG);
+TRACE_DEFINE_ENUM(SSAM_SSH_TC_SPT);
+TRACE_DEFINE_ENUM(SSAM_SSH_TC_SYS);
+TRACE_DEFINE_ENUM(SSAM_SSH_TC_ACC1);
+TRACE_DEFINE_ENUM(SSAM_SSH_TC_SHB);
+TRACE_DEFINE_ENUM(SSAM_SSH_TC_POS);
 
 #define SSAM_PTR_UID_LEN		9
 #define SSAM_U8_FIELD_NOT_APPLICABLE	((u16)-1)
@@ -229,40 +234,45 @@ static inline u32 ssam_trace_get_request_tc(const struct ssh_packet *p)
 
 #define ssam_show_ssh_tc(rqid)						\
 	__print_symbolic(rqid,						\
-		{ SSAM_SSH_TC_NOT_APPLICABLE,		"N/A" },	\
-		{ SSAM_SSH_TC_SAM,			"SAM" },	\
-		{ SSAM_SSH_TC_BAT,			"BAT" },	\
-		{ SSAM_SSH_TC_TMP,			"TMP" },	\
-		{ SSAM_SSH_TC_PMC,			"PMC" },	\
-		{ SSAM_SSH_TC_FAN,			"FAN" },	\
-		{ SSAM_SSH_TC_PoM,			"PoM" },	\
-		{ SSAM_SSH_TC_DBG,			"DBG" },	\
-		{ SSAM_SSH_TC_KBD,			"KBD" },	\
-		{ SSAM_SSH_TC_FWU,			"FWU" },	\
-		{ SSAM_SSH_TC_UNI,			"UNI" },	\
-		{ SSAM_SSH_TC_LPC,			"LPC" },	\
-		{ SSAM_SSH_TC_TCL,			"TCL" },	\
-		{ SSAM_SSH_TC_SFL,			"SFL" },	\
-		{ SSAM_SSH_TC_KIP,			"KIP" },	\
-		{ SSAM_SSH_TC_EXT,			"EXT" },	\
-		{ SSAM_SSH_TC_BLD,			"BLD" },	\
-		{ SSAM_SSH_TC_BAS,			"BAS" },	\
-		{ SSAM_SSH_TC_SEN,			"SEN" },	\
-		{ SSAM_SSH_TC_SRQ,			"SRQ" },	\
-		{ SSAM_SSH_TC_MCU,			"MCU" },	\
-		{ SSAM_SSH_TC_HID,			"HID" },	\
-		{ SSAM_SSH_TC_TCH,			"TCH" },	\
-		{ SSAM_SSH_TC_BKL,			"BKL" },	\
-		{ SSAM_SSH_TC_TAM,			"TAM" },	\
-		{ SSAM_SSH_TC_ACC,			"ACC" },	\
-		{ SSAM_SSH_TC_UFI,			"UFI" },	\
-		{ SSAM_SSH_TC_USC,			"USC" },	\
-		{ SSAM_SSH_TC_PEN,			"PEN" },	\
-		{ SSAM_SSH_TC_VID,			"VID" },	\
-		{ SSAM_SSH_TC_AUD,			"AUD" },	\
-		{ SSAM_SSH_TC_SMC,			"SMC" },	\
-		{ SSAM_SSH_TC_KPD,			"KPD" },	\
-		{ SSAM_SSH_TC_REG,			"REG" }		\
+		{ SSAM_SSH_TC_NOT_APPLICABLE,		"N/A"  },	\
+		{ SSAM_SSH_TC_SAM,			"SAM"  },	\
+		{ SSAM_SSH_TC_BAT,			"BAT"  },	\
+		{ SSAM_SSH_TC_TMP,			"TMP"  },	\
+		{ SSAM_SSH_TC_PMC,			"PMC"  },	\
+		{ SSAM_SSH_TC_FAN,			"FAN"  },	\
+		{ SSAM_SSH_TC_PoM,			"PoM"  },	\
+		{ SSAM_SSH_TC_DBG,			"DBG"  },	\
+		{ SSAM_SSH_TC_KBD,			"KBD"  },	\
+		{ SSAM_SSH_TC_FWU,			"FWU"  },	\
+		{ SSAM_SSH_TC_UNI,			"UNI"  },	\
+		{ SSAM_SSH_TC_LPC,			"LPC"  },	\
+		{ SSAM_SSH_TC_TCL,			"TCL"  },	\
+		{ SSAM_SSH_TC_SFL,			"SFL"  },	\
+		{ SSAM_SSH_TC_KIP,			"KIP"  },	\
+		{ SSAM_SSH_TC_EXT,			"EXT"  },	\
+		{ SSAM_SSH_TC_BLD,			"BLD"  },	\
+		{ SSAM_SSH_TC_BAS,			"BAS"  },	\
+		{ SSAM_SSH_TC_SEN,			"SEN"  },	\
+		{ SSAM_SSH_TC_SRQ,			"SRQ"  },	\
+		{ SSAM_SSH_TC_MCU,			"MCU"  },	\
+		{ SSAM_SSH_TC_HID,			"HID"  },	\
+		{ SSAM_SSH_TC_TCH,			"TCH"  },	\
+		{ SSAM_SSH_TC_BKL,			"BKL"  },	\
+		{ SSAM_SSH_TC_TAM,			"TAM"  },	\
+		{ SSAM_SSH_TC_ACC0,			"ACC0" },	\
+		{ SSAM_SSH_TC_UFI,			"UFI"  },	\
+		{ SSAM_SSH_TC_USC,			"USC"  },	\
+		{ SSAM_SSH_TC_PEN,			"PEN"  },	\
+		{ SSAM_SSH_TC_VID,			"VID"  },	\
+		{ SSAM_SSH_TC_AUD,			"AUD"  },	\
+		{ SSAM_SSH_TC_SMC,			"SMC"  },	\
+		{ SSAM_SSH_TC_KPD,			"KPD"  },	\
+		{ SSAM_SSH_TC_REG,			"REG"  },	\
+		{ SSAM_SSH_TC_SPT,			"SPT"  },	\
+		{ SSAM_SSH_TC_SYS,			"SYS"  },	\
+		{ SSAM_SSH_TC_ACC1,			"ACC1" },	\
+		{ SSAM_SSH_TC_SHB,			"SMB"  },	\
+		{ SSAM_SSH_TC_POS,			"POS"  }	\
 	)
 
 DECLARE_EVENT_CLASS(ssam_frame_class,
diff --git a/include/linux/surface_aggregator/serial_hub.h b/include/linux/surface_aggregator/serial_hub.h
index 26b95ec12733..45501b6e54e8 100644
--- a/include/linux/surface_aggregator/serial_hub.h
+++ b/include/linux/surface_aggregator/serial_hub.h
@@ -201,7 +201,7 @@ static inline u16 ssh_crc(const u8 *buf, size_t len)
  * exception of zero, which is not an event ID. Thus, this is also the
  * absolute maximum number of event handlers that can be registered.
  */
-#define SSH_NUM_EVENTS		34
+#define SSH_NUM_EVENTS		38
 
 /*
  * SSH_NUM_TARGETS - The number of communication targets used in the protocol.
@@ -292,40 +292,45 @@ struct ssam_span {
  * Windows driver.
  */
 enum ssam_ssh_tc {
-				/* Category 0x00 is invalid for EC use. */
-	SSAM_SSH_TC_SAM = 0x01,	/* Generic system functionality, real-time clock. */
-	SSAM_SSH_TC_BAT = 0x02,	/* Battery/power subsystem. */
-	SSAM_SSH_TC_TMP = 0x03,	/* Thermal subsystem. */
-	SSAM_SSH_TC_PMC = 0x04,
-	SSAM_SSH_TC_FAN = 0x05,
-	SSAM_SSH_TC_PoM = 0x06,
-	SSAM_SSH_TC_DBG = 0x07,
-	SSAM_SSH_TC_KBD = 0x08,	/* Legacy keyboard (Laptop 1/2). */
-	SSAM_SSH_TC_FWU = 0x09,
-	SSAM_SSH_TC_UNI = 0x0a,
-	SSAM_SSH_TC_LPC = 0x0b,
-	SSAM_SSH_TC_TCL = 0x0c,
-	SSAM_SSH_TC_SFL = 0x0d,
-	SSAM_SSH_TC_KIP = 0x0e,	/* Manages detachable peripherals (Pro X/8 keyboard cover) */
-	SSAM_SSH_TC_EXT = 0x0f,
-	SSAM_SSH_TC_BLD = 0x10,
-	SSAM_SSH_TC_BAS = 0x11,	/* Detachment system (Surface Book 2/3). */
-	SSAM_SSH_TC_SEN = 0x12,
-	SSAM_SSH_TC_SRQ = 0x13,
-	SSAM_SSH_TC_MCU = 0x14,
-	SSAM_SSH_TC_HID = 0x15,	/* Generic HID input subsystem. */
-	SSAM_SSH_TC_TCH = 0x16,
-	SSAM_SSH_TC_BKL = 0x17,
-	SSAM_SSH_TC_TAM = 0x18,
-	SSAM_SSH_TC_ACC = 0x19,
-	SSAM_SSH_TC_UFI = 0x1a,
-	SSAM_SSH_TC_USC = 0x1b,
-	SSAM_SSH_TC_PEN = 0x1c,
-	SSAM_SSH_TC_VID = 0x1d,
-	SSAM_SSH_TC_AUD = 0x1e,
-	SSAM_SSH_TC_SMC = 0x1f,
-	SSAM_SSH_TC_KPD = 0x20,
-	SSAM_SSH_TC_REG = 0x21,	/* Extended event registry. */
+				  /* Category 0x00 is invalid for EC use. */
+	SSAM_SSH_TC_SAM  = 0x01,  /* Generic system functionality, real-time clock. */
+	SSAM_SSH_TC_BAT  = 0x02,  /* Battery/power subsystem. */
+	SSAM_SSH_TC_TMP  = 0x03,  /* Thermal subsystem. */
+	SSAM_SSH_TC_PMC  = 0x04,
+	SSAM_SSH_TC_FAN  = 0x05,
+	SSAM_SSH_TC_PoM  = 0x06,
+	SSAM_SSH_TC_DBG  = 0x07,
+	SSAM_SSH_TC_KBD  = 0x08,  /* Legacy keyboard (Laptop 1/2). */
+	SSAM_SSH_TC_FWU  = 0x09,
+	SSAM_SSH_TC_UNI  = 0x0a,
+	SSAM_SSH_TC_LPC  = 0x0b,
+	SSAM_SSH_TC_TCL  = 0x0c,
+	SSAM_SSH_TC_SFL  = 0x0d,
+	SSAM_SSH_TC_KIP  = 0x0e,  /* Manages detachable peripherals (Pro X/8 keyboard cover) */
+	SSAM_SSH_TC_EXT  = 0x0f,
+	SSAM_SSH_TC_BLD  = 0x10,
+	SSAM_SSH_TC_BAS  = 0x11,  /* Detachment system (Surface Book 2/3). */
+	SSAM_SSH_TC_SEN  = 0x12,
+	SSAM_SSH_TC_SRQ  = 0x13,
+	SSAM_SSH_TC_MCU  = 0x14,
+	SSAM_SSH_TC_HID  = 0x15,  /* Generic HID input subsystem. */
+	SSAM_SSH_TC_TCH  = 0x16,
+	SSAM_SSH_TC_BKL  = 0x17,
+	SSAM_SSH_TC_TAM  = 0x18,
+	SSAM_SSH_TC_ACC0 = 0x19,
+	SSAM_SSH_TC_UFI  = 0x1a,
+	SSAM_SSH_TC_USC  = 0x1b,
+	SSAM_SSH_TC_PEN  = 0x1c,
+	SSAM_SSH_TC_VID  = 0x1d,
+	SSAM_SSH_TC_AUD  = 0x1e,
+	SSAM_SSH_TC_SMC  = 0x1f,
+	SSAM_SSH_TC_KPD  = 0x20,
+	SSAM_SSH_TC_REG  = 0x21,  /* Extended event registry. */
+	SSAM_SSH_TC_SPT  = 0x22,
+	SSAM_SSH_TC_SYS  = 0x23,
+	SSAM_SSH_TC_ACC1 = 0x24,
+	SSAM_SSH_TC_SHB  = 0x25,
+	SSAM_SSH_TC_POS  = 0x26,  /* For obtaining Laptop Studio screen position. */
 };
 
 
-- 
2.38.0

From bb44dfeb982ea5fdf9d18982512084eeca71ed7f Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 24 Jun 2022 20:36:39 +0200
Subject: [PATCH] platform/surface: aggregator: Add helper macros for requests
 with argument and return value

Add helper macros for synchronous stack-allocated Surface Aggregator
request with both argument and return value, similar to the current
argument-only and return-value-only ones.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220624183642.910893-2-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 include/linux/surface_aggregator/controller.h | 125 ++++++++++++++++++
 include/linux/surface_aggregator/device.h     |  36 +++++
 2 files changed, 161 insertions(+)

diff --git a/include/linux/surface_aggregator/controller.h b/include/linux/surface_aggregator/controller.h
index 50a2b4926c06..d11a1c6e3186 100644
--- a/include/linux/surface_aggregator/controller.h
+++ b/include/linux/surface_aggregator/controller.h
@@ -469,6 +469,67 @@ struct ssam_request_spec_md {
 		return 0;							\
 	}
 
+/**
+ * SSAM_DEFINE_SYNC_REQUEST_WR() - Define synchronous SAM request function with
+ * both argument and return value.
+ * @name:  Name of the generated function.
+ * @atype: Type of the request's argument.
+ * @rtype: Type of the request's return value.
+ * @spec:  Specification (&struct ssam_request_spec) defining the request.
+ *
+ * Defines a function executing the synchronous SAM request specified by @spec,
+ * with the request taking an argument of type @atype and having a return value
+ * of type @rtype. The generated function takes care of setting up the request
+ * and response structs, buffer allocation, as well as execution of the request
+ * itself, returning once the request has been fully completed. The required
+ * transport buffer will be allocated on the stack.
+ *
+ * The generated function is defined as ``static int name(struct
+ * ssam_controller *ctrl, const atype *arg, rtype *ret)``, returning the status
+ * of the request, which is zero on success and negative on failure. The
+ * ``ctrl`` parameter is the controller via which the request is sent. The
+ * request argument is specified via the ``arg`` pointer. The request's return
+ * value is written to the memory pointed to by the ``ret`` parameter.
+ *
+ * Refer to ssam_request_sync_onstack() for more details on the behavior of
+ * the generated function.
+ */
+#define SSAM_DEFINE_SYNC_REQUEST_WR(name, atype, rtype, spec...)		\
+	static int name(struct ssam_controller *ctrl, const atype *arg, rtype *ret) \
+	{									\
+		struct ssam_request_spec s = (struct ssam_request_spec)spec;	\
+		struct ssam_request rqst;					\
+		struct ssam_response rsp;					\
+		int status;							\
+										\
+		rqst.target_category = s.target_category;			\
+		rqst.target_id = s.target_id;					\
+		rqst.command_id = s.command_id;					\
+		rqst.instance_id = s.instance_id;				\
+		rqst.flags = s.flags | SSAM_REQUEST_HAS_RESPONSE;		\
+		rqst.length = sizeof(atype);					\
+		rqst.payload = (u8 *)arg;					\
+										\
+		rsp.capacity = sizeof(rtype);					\
+		rsp.length = 0;							\
+		rsp.pointer = (u8 *)ret;					\
+										\
+		status = ssam_request_sync_onstack(ctrl, &rqst, &rsp, sizeof(atype)); \
+		if (status)							\
+			return status;						\
+										\
+		if (rsp.length != sizeof(rtype)) {				\
+			struct device *dev = ssam_controller_device(ctrl);	\
+			dev_err(dev,						\
+				"rqst: invalid response length, expected %zu, got %zu (tc: %#04x, cid: %#04x)", \
+				sizeof(rtype), rsp.length, rqst.target_category,\
+				rqst.command_id);				\
+			return -EIO;						\
+		}								\
+										\
+		return 0;							\
+	}
+
 /**
  * SSAM_DEFINE_SYNC_REQUEST_MD_N() - Define synchronous multi-device SAM
  * request function with neither argument nor return value.
@@ -613,6 +674,70 @@ struct ssam_request_spec_md {
 		return 0;							\
 	}
 
+/**
+ * SSAM_DEFINE_SYNC_REQUEST_MD_WR() - Define synchronous multi-device SAM
+ * request function with both argument and return value.
+ * @name:  Name of the generated function.
+ * @atype: Type of the request's argument.
+ * @rtype: Type of the request's return value.
+ * @spec:  Specification (&struct ssam_request_spec_md) defining the request.
+ *
+ * Defines a function executing the synchronous SAM request specified by @spec,
+ * with the request taking an argument of type @atype and having a return value
+ * of type @rtype. Device specifying parameters are not hard-coded, but instead
+ * must be provided to the function. The generated function takes care of
+ * setting up the request and response structs, buffer allocation, as well as
+ * execution of the request itself, returning once the request has been fully
+ * completed. The required transport buffer will be allocated on the stack.
+ *
+ * The generated function is defined as ``static int name(struct
+ * ssam_controller *ctrl, u8 tid, u8 iid, const atype *arg, rtype *ret)``,
+ * returning the status of the request, which is zero on success and negative
+ * on failure. The ``ctrl`` parameter is the controller via which the request
+ * is sent, ``tid`` the target ID for the request, and ``iid`` the instance ID.
+ * The request argument is specified via the ``arg`` pointer. The request's
+ * return value is written to the memory pointed to by the ``ret`` parameter.
+ *
+ * Refer to ssam_request_sync_onstack() for more details on the behavior of
+ * the generated function.
+ */
+#define SSAM_DEFINE_SYNC_REQUEST_MD_WR(name, atype, rtype, spec...)		\
+	static int name(struct ssam_controller *ctrl, u8 tid, u8 iid,		\
+			const atype *arg, rtype *ret)				\
+	{									\
+		struct ssam_request_spec_md s = (struct ssam_request_spec_md)spec; \
+		struct ssam_request rqst;					\
+		struct ssam_response rsp;					\
+		int status;							\
+										\
+		rqst.target_category = s.target_category;			\
+		rqst.target_id = tid;						\
+		rqst.command_id = s.command_id;					\
+		rqst.instance_id = iid;						\
+		rqst.flags = s.flags | SSAM_REQUEST_HAS_RESPONSE;		\
+		rqst.length = sizeof(atype);					\
+		rqst.payload = (u8 *)arg;					\
+										\
+		rsp.capacity = sizeof(rtype);					\
+		rsp.length = 0;							\
+		rsp.pointer = (u8 *)ret;					\
+										\
+		status = ssam_request_sync_onstack(ctrl, &rqst, &rsp, sizeof(atype)); \
+		if (status)							\
+			return status;						\
+										\
+		if (rsp.length != sizeof(rtype)) {				\
+			struct device *dev = ssam_controller_device(ctrl);	\
+			dev_err(dev,						\
+				"rqst: invalid response length, expected %zu, got %zu (tc: %#04x, cid: %#04x)", \
+				sizeof(rtype), rsp.length, rqst.target_category,\
+				rqst.command_id);				\
+			return -EIO;						\
+		}								\
+										\
+		return 0;							\
+	}
+
 
 /* -- Event notifier/callbacks. --------------------------------------------- */
 
diff --git a/include/linux/surface_aggregator/device.h b/include/linux/surface_aggregator/device.h
index c418f7f2732d..6cf7e80312d5 100644
--- a/include/linux/surface_aggregator/device.h
+++ b/include/linux/surface_aggregator/device.h
@@ -483,6 +483,42 @@ static inline void ssam_remove_clients(struct device *dev) {}
 				    sdev->uid.instance, ret);		\
 	}
 
+/**
+ * SSAM_DEFINE_SYNC_REQUEST_CL_WR() - Define synchronous client-device SAM
+ * request function with argument and return value.
+ * @name:  Name of the generated function.
+ * @atype: Type of the request's argument.
+ * @rtype: Type of the request's return value.
+ * @spec:  Specification (&struct ssam_request_spec_md) defining the request.
+ *
+ * Defines a function executing the synchronous SAM request specified by @spec,
+ * with the request taking an argument of type @atype and having a return value
+ * of type @rtype. Device specifying parameters are not hard-coded, but instead
+ * are provided via the client device, specifically its UID, supplied when
+ * calling this function. The generated function takes care of setting up the
+ * request struct, buffer allocation, as well as execution of the request
+ * itself, returning once the request has been fully completed. The required
+ * transport buffer will be allocated on the stack.
+ *
+ * The generated function is defined as ``static int name(struct ssam_device
+ * *sdev, const atype *arg, rtype *ret)``, returning the status of the request,
+ * which is zero on success and negative on failure. The ``sdev`` parameter
+ * specifies both the target device of the request and by association the
+ * controller via which the request is sent. The request's argument is
+ * specified via the ``arg`` pointer. The request's return value is written to
+ * the memory pointed to by the ``ret`` parameter.
+ *
+ * Refer to ssam_request_sync_onstack() for more details on the behavior of
+ * the generated function.
+ */
+#define SSAM_DEFINE_SYNC_REQUEST_CL_WR(name, atype, rtype, spec...)		\
+	SSAM_DEFINE_SYNC_REQUEST_MD_WR(__raw_##name, atype, rtype, spec)	\
+	static int name(struct ssam_device *sdev, const atype *arg, rtype *ret)	\
+	{									\
+		return __raw_##name(sdev->ctrl, sdev->uid.target,		\
+				    sdev->uid.instance, arg, ret);		\
+	}
+
 
 /* -- Helpers for client-device notifiers. ---------------------------------- */
 
-- 
2.38.0

From b0e8cc2fefdf4e572e6ce71b0bf60b9e63022ed1 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 24 Jun 2022 20:36:40 +0200
Subject: [PATCH] platform/surface: Add KIP/POS tablet-mode switch driver
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Add a driver providing a tablet-mode switch input device for Microsoft
Surface devices using the Surface Aggregator KIP subsystem (to manage
detachable peripherals) or POS subsystem (to obtain device posture
information).

The KIP (full name unknown, abbreviation found through reverse
engineering) subsystem is used on the Surface Pro 8 and Surface Pro X to
manage the keyboard cover. Among other things, it provides information
on the positioning (posture) of the cover (closed, laptop-style,
detached, folded-back, ...), which can be used to implement an input
device providing the SW_TABLET_MODE event. Similarly, the POS (posture
information) subsystem provides such information on the Surface Laptop
Studio, with the difference being that the keyboard is not detachable.

As implementing the tablet-mode switch for both subsystems is largely
similar, the driver proposed in this commit, in large, acts as a generic
tablet mode switch driver framework for the Surface Aggregator Module.
Specific implementations using this framework are provided for the KIP
and POS subsystems, adding tablet-mode switch support to the
aforementioned devices.

A few more notes on the Surface Laptop Studio:

A peculiarity of the Surface Laptop Studio is its "slate/tent" mode
(symbolized: user> _/\). In this mode, the screen covers the keyboard
but leaves the touchpad exposed. This is essentially a mode in-between
tablet and laptop, and it is debatable whether tablet-mode should be
enabled in this mode. We therefore let the user decide this via a module
parameter.

In particular, tablet-mode may bring up the on-screen touch keyboard
more easily, which would be desirable in this mode. However, some
user-space software currently also decides to disable keyboard and, more
importantly, touchpad input, while the touchpad is still accessible in
the "slate/tent" mode. Furthermore, this mode shares its identifier with
"slate/flipped" mode where the screen is flipped 180° and the keyboard
points away from the user (symbolized: user> /_). In this mode we would
like to enable auto-rotation, something that user-space software may
only do when tablet-mode is enabled. We therefore default to the
slate-mode enabling the tablet-mode switch.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220624183642.910893-3-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 .../sysfs-bus-surface_aggregator-tabletsw     |  57 ++
 MAINTAINERS                                   |   6 +
 drivers/platform/surface/Kconfig              |  23 +
 drivers/platform/surface/Makefile             |   1 +
 .../surface/surface_aggregator_tabletsw.c     | 533 ++++++++++++++++++
 5 files changed, 620 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-bus-surface_aggregator-tabletsw
 create mode 100644 drivers/platform/surface/surface_aggregator_tabletsw.c

diff --git a/Documentation/ABI/testing/sysfs-bus-surface_aggregator-tabletsw b/Documentation/ABI/testing/sysfs-bus-surface_aggregator-tabletsw
new file mode 100644
index 000000000000..74cd9d754e60
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-surface_aggregator-tabletsw
@@ -0,0 +1,57 @@
+What:		/sys/bus/surface_aggregator/devices/01:0e:01:00:01/state
+Date:		July 2022
+KernelVersion:	5.20
+Contact:	Maximilian Luz <luzmaximilian@gmail.com>
+Description:
+		This attribute returns a string with the current type-cover
+		or device posture, as indicated by the embedded controller.
+		Currently returned posture states are:
+
+		- "disconnected": The type-cover has been disconnected.
+
+		- "closed": The type-cover has been folded closed and lies on
+		  top of the display.
+
+		- "laptop": The type-cover is open and in laptop-mode, i.e.,
+		  ready for normal use.
+
+		- "folded-canvas": The type-cover has been folded back
+		  part-ways, but does not lie flush with the back side of the
+		  device. In general, this means that the kick-stand is used
+		  and extended atop of the cover.
+
+		- "folded-back": The type cover has been fully folded back and
+		  lies flush with the back side of the device.
+
+		- "<unknown>": The current state is unknown to the driver, for
+		  example due to newer as-of-yet unsupported hardware.
+
+		New states may be introduced with new hardware. Users therefore
+		must not rely on this list of states being exhaustive and
+		gracefully handle unknown states.
+
+What:		/sys/bus/surface_aggregator/devices/01:26:01:00:01/state
+Date:		July 2022
+KernelVersion:	5.20
+Contact:	Maximilian Luz <luzmaximilian@gmail.com>
+Description:
+		This attribute returns a string with the current device posture, as indicated by the embedded controller. Currently
+		returned posture states are:
+
+		- "closed": The lid of the device is closed.
+
+		- "laptop": The lid of the device is opened and the device
+		  operates as a normal laptop.
+
+		- "slate": The screen covers the keyboard or has been flipped
+		  back and the device operates mainly based on touch input.
+
+		- "tablet": The device operates as tablet and exclusively
+		  relies on touch input (or external peripherals).
+
+		- "<unknown>": The current state is unknown to the driver, for
+		  example due to newer as-of-yet unsupported hardware.
+
+		New states may be introduced with new hardware. Users therefore
+		must not rely on this list of states being exhaustive and
+		gracefully handle unknown states.
diff --git a/MAINTAINERS b/MAINTAINERS
index 08620b9a44fc..773eb8387f4a 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -13299,6 +13299,12 @@ F:	drivers/scsi/smartpqi/smartpqi*.[ch]
 F:	include/linux/cciss*.h
 F:	include/uapi/linux/cciss*.h
 
+MICROSOFT SURFACE AGGREGATOR TABLET-MODE SWITCH
+M:	Maximilian Luz <luzmaximilian@gmail.com>
+L:	platform-driver-x86@vger.kernel.org
+S:	Maintained
+F:	drivers/platform/surface/surface_aggregator_tablet_switch.c
+
 MICROSOFT SURFACE BATTERY AND AC DRIVERS
 M:	Maximilian Luz <luzmaximilian@gmail.com>
 L:	linux-pm@vger.kernel.org
diff --git a/drivers/platform/surface/Kconfig b/drivers/platform/surface/Kconfig
index eb79fbed8059..b152e930cc84 100644
--- a/drivers/platform/surface/Kconfig
+++ b/drivers/platform/surface/Kconfig
@@ -99,6 +99,29 @@ config SURFACE_AGGREGATOR_REGISTRY
 	  the respective client devices. Drivers for these devices still need to
 	  be selected via the other options.
 
+config SURFACE_AGGREGATOR_TABLET_SWITCH
+	tristate "Surface Aggregator Generic Tablet-Mode Switch Driver"
+	depends on SURFACE_AGGREGATOR
+	depends on SURFACE_AGGREGATOR_BUS
+	depends on INPUT
+	help
+	  Provides a tablet-mode switch input device on Microsoft Surface models
+	  using the KIP subsystem for detachable keyboards (e.g. keyboard covers)
+	  or the POS subsystem for device/screen posture changes.
+
+	  The KIP subsystem is used on newer Surface generations to handle
+	  detachable input peripherals, specifically the keyboard cover (containing
+	  keyboard and touchpad) on the Surface Pro 8 and Surface Pro X. The POS
+	  subsystem is used for device posture change notifications on the Surface
+	  Laptop Studio. This module provides a driver to let user-space know when
+	  the device should be considered in tablet-mode due to the keyboard cover
+	  being detached or folded back (essentially signaling when the keyboard is
+	  not available for input). It does so by creating a tablet-mode switch
+	  input device, sending the standard SW_TABLET_MODE event on mode change.
+
+	  Select M or Y here, if you want to provide tablet-mode switch input
+	  events on the Surface Pro 8, Surface Pro X, and Surface Laptop Studio.
+
 config SURFACE_DTX
 	tristate "Surface DTX (Detachment System) Driver"
 	depends on SURFACE_AGGREGATOR
diff --git a/drivers/platform/surface/Makefile b/drivers/platform/surface/Makefile
index 0fc9cd3e4dd9..18b27898543e 100644
--- a/drivers/platform/surface/Makefile
+++ b/drivers/platform/surface/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_SURFACE_ACPI_NOTIFY)	+= surface_acpi_notify.o
 obj-$(CONFIG_SURFACE_AGGREGATOR)	+= aggregator/
 obj-$(CONFIG_SURFACE_AGGREGATOR_CDEV)	+= surface_aggregator_cdev.o
 obj-$(CONFIG_SURFACE_AGGREGATOR_REGISTRY) += surface_aggregator_registry.o
+obj-$(CONFIG_SURFACE_AGGREGATOR_TABLET_SWITCH) += surface_aggregator_tabletsw.o
 obj-$(CONFIG_SURFACE_DTX)		+= surface_dtx.o
 obj-$(CONFIG_SURFACE_GPE)		+= surface_gpe.o
 obj-$(CONFIG_SURFACE_HOTPLUG)		+= surface_hotplug.o
diff --git a/drivers/platform/surface/surface_aggregator_tabletsw.c b/drivers/platform/surface/surface_aggregator_tabletsw.c
new file mode 100644
index 000000000000..596ca6c80681
--- /dev/null
+++ b/drivers/platform/surface/surface_aggregator_tabletsw.c
@@ -0,0 +1,533 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Surface System Aggregator Module (SSAM) tablet mode switch driver.
+ *
+ * Copyright (C) 2022 Maximilian Luz <luzmaximilian@gmail.com>
+ */
+
+#include <asm/unaligned.h>
+#include <linux/input.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/workqueue.h>
+
+#include <linux/surface_aggregator/controller.h>
+#include <linux/surface_aggregator/device.h>
+
+
+/* -- SSAM generic tablet switch driver framework. -------------------------- */
+
+struct ssam_tablet_sw;
+
+struct ssam_tablet_sw_ops {
+	int (*get_state)(struct ssam_tablet_sw *sw, u32 *state);
+	const char *(*state_name)(struct ssam_tablet_sw *sw, u32 state);
+	bool (*state_is_tablet_mode)(struct ssam_tablet_sw *sw, u32 state);
+};
+
+struct ssam_tablet_sw {
+	struct ssam_device *sdev;
+
+	u32 state;
+	struct work_struct update_work;
+	struct input_dev *mode_switch;
+
+	struct ssam_tablet_sw_ops ops;
+	struct ssam_event_notifier notif;
+};
+
+struct ssam_tablet_sw_desc {
+	struct {
+		const char *name;
+		const char *phys;
+	} dev;
+
+	struct {
+		u32 (*notify)(struct ssam_event_notifier *nf, const struct ssam_event *event);
+		int (*get_state)(struct ssam_tablet_sw *sw, u32 *state);
+		const char *(*state_name)(struct ssam_tablet_sw *sw, u32 state);
+		bool (*state_is_tablet_mode)(struct ssam_tablet_sw *sw, u32 state);
+	} ops;
+
+	struct {
+		struct ssam_event_registry reg;
+		struct ssam_event_id id;
+		enum ssam_event_mask mask;
+		u8 flags;
+	} event;
+};
+
+static ssize_t state_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct ssam_tablet_sw *sw = dev_get_drvdata(dev);
+	const char *state = sw->ops.state_name(sw, sw->state);
+
+	return sysfs_emit(buf, "%s\n", state);
+}
+static DEVICE_ATTR_RO(state);
+
+static struct attribute *ssam_tablet_sw_attrs[] = {
+	&dev_attr_state.attr,
+	NULL,
+};
+
+static const struct attribute_group ssam_tablet_sw_group = {
+	.attrs = ssam_tablet_sw_attrs,
+};
+
+static void ssam_tablet_sw_update_workfn(struct work_struct *work)
+{
+	struct ssam_tablet_sw *sw = container_of(work, struct ssam_tablet_sw, update_work);
+	int tablet, status;
+	u32 state;
+
+	status = sw->ops.get_state(sw, &state);
+	if (status)
+		return;
+
+	if (sw->state == state)
+		return;
+	sw->state = state;
+
+	/* Send SW_TABLET_MODE event. */
+	tablet = sw->ops.state_is_tablet_mode(sw, state);
+	input_report_switch(sw->mode_switch, SW_TABLET_MODE, tablet);
+	input_sync(sw->mode_switch);
+}
+
+static int __maybe_unused ssam_tablet_sw_resume(struct device *dev)
+{
+	struct ssam_tablet_sw *sw = dev_get_drvdata(dev);
+
+	schedule_work(&sw->update_work);
+	return 0;
+}
+static SIMPLE_DEV_PM_OPS(ssam_tablet_sw_pm_ops, NULL, ssam_tablet_sw_resume);
+
+static int ssam_tablet_sw_probe(struct ssam_device *sdev)
+{
+	const struct ssam_tablet_sw_desc *desc;
+	struct ssam_tablet_sw *sw;
+	int tablet, status;
+
+	desc = ssam_device_get_match_data(sdev);
+	if (!desc) {
+		WARN(1, "no driver match data specified");
+		return -EINVAL;
+	}
+
+	sw = devm_kzalloc(&sdev->dev, sizeof(*sw), GFP_KERNEL);
+	if (!sw)
+		return -ENOMEM;
+
+	sw->sdev = sdev;
+
+	sw->ops.get_state = desc->ops.get_state;
+	sw->ops.state_name = desc->ops.state_name;
+	sw->ops.state_is_tablet_mode = desc->ops.state_is_tablet_mode;
+
+	INIT_WORK(&sw->update_work, ssam_tablet_sw_update_workfn);
+
+	ssam_device_set_drvdata(sdev, sw);
+
+	/* Get initial state. */
+	status = sw->ops.get_state(sw, &sw->state);
+	if (status)
+		return status;
+
+	/* Set up tablet mode switch. */
+	sw->mode_switch = devm_input_allocate_device(&sdev->dev);
+	if (!sw->mode_switch)
+		return -ENOMEM;
+
+	sw->mode_switch->name = desc->dev.name;
+	sw->mode_switch->phys = desc->dev.phys;
+	sw->mode_switch->id.bustype = BUS_HOST;
+	sw->mode_switch->dev.parent = &sdev->dev;
+
+	tablet = sw->ops.state_is_tablet_mode(sw, sw->state);
+	input_set_capability(sw->mode_switch, EV_SW, SW_TABLET_MODE);
+	input_report_switch(sw->mode_switch, SW_TABLET_MODE, tablet);
+
+	status = input_register_device(sw->mode_switch);
+	if (status)
+		return status;
+
+	/* Set up notifier. */
+	sw->notif.base.priority = 0;
+	sw->notif.base.fn = desc->ops.notify;
+	sw->notif.event.reg = desc->event.reg;
+	sw->notif.event.id = desc->event.id;
+	sw->notif.event.mask = desc->event.mask;
+	sw->notif.event.flags = SSAM_EVENT_SEQUENCED;
+
+	status = ssam_device_notifier_register(sdev, &sw->notif);
+	if (status)
+		return status;
+
+	status = sysfs_create_group(&sdev->dev.kobj, &ssam_tablet_sw_group);
+	if (status)
+		goto err;
+
+	/* We might have missed events during setup, so check again. */
+	schedule_work(&sw->update_work);
+	return 0;
+
+err:
+	ssam_device_notifier_unregister(sdev, &sw->notif);
+	cancel_work_sync(&sw->update_work);
+	return status;
+}
+
+static void ssam_tablet_sw_remove(struct ssam_device *sdev)
+{
+	struct ssam_tablet_sw *sw = ssam_device_get_drvdata(sdev);
+
+	sysfs_remove_group(&sdev->dev.kobj, &ssam_tablet_sw_group);
+
+	ssam_device_notifier_unregister(sdev, &sw->notif);
+	cancel_work_sync(&sw->update_work);
+}
+
+
+/* -- SSAM KIP tablet switch implementation. -------------------------------- */
+
+#define SSAM_EVENT_KIP_CID_COVER_STATE_CHANGED	0x1d
+
+enum ssam_kip_cover_state {
+	SSAM_KIP_COVER_STATE_DISCONNECTED  = 0x01,
+	SSAM_KIP_COVER_STATE_CLOSED        = 0x02,
+	SSAM_KIP_COVER_STATE_LAPTOP        = 0x03,
+	SSAM_KIP_COVER_STATE_FOLDED_CANVAS = 0x04,
+	SSAM_KIP_COVER_STATE_FOLDED_BACK   = 0x05,
+};
+
+static const char *ssam_kip_cover_state_name(struct ssam_tablet_sw *sw, u32 state)
+{
+	switch (state) {
+	case SSAM_KIP_COVER_STATE_DISCONNECTED:
+		return "disconnected";
+
+	case SSAM_KIP_COVER_STATE_CLOSED:
+		return "closed";
+
+	case SSAM_KIP_COVER_STATE_LAPTOP:
+		return "laptop";
+
+	case SSAM_KIP_COVER_STATE_FOLDED_CANVAS:
+		return "folded-canvas";
+
+	case SSAM_KIP_COVER_STATE_FOLDED_BACK:
+		return "folded-back";
+
+	default:
+		dev_warn(&sw->sdev->dev, "unknown KIP cover state: %u\n", state);
+		return "<unknown>";
+	}
+}
+
+static bool ssam_kip_cover_state_is_tablet_mode(struct ssam_tablet_sw *sw, u32 state)
+{
+	switch (state) {
+	case SSAM_KIP_COVER_STATE_DISCONNECTED:
+	case SSAM_KIP_COVER_STATE_FOLDED_CANVAS:
+	case SSAM_KIP_COVER_STATE_FOLDED_BACK:
+		return true;
+
+	case SSAM_KIP_COVER_STATE_CLOSED:
+	case SSAM_KIP_COVER_STATE_LAPTOP:
+		return false;
+
+	default:
+		dev_warn(&sw->sdev->dev, "unknown KIP cover state: %d\n", sw->state);
+		return true;
+	}
+}
+
+SSAM_DEFINE_SYNC_REQUEST_R(__ssam_kip_get_cover_state, u8, {
+	.target_category = SSAM_SSH_TC_KIP,
+	.target_id       = 0x01,
+	.command_id      = 0x1d,
+	.instance_id     = 0x00,
+});
+
+static int ssam_kip_get_cover_state(struct ssam_tablet_sw *sw, u32 *state)
+{
+	int status;
+	u8 raw;
+
+	status = ssam_retry(__ssam_kip_get_cover_state, sw->sdev->ctrl, &raw);
+	if (status < 0) {
+		dev_err(&sw->sdev->dev, "failed to query KIP lid state: %d\n", status);
+		return status;
+	}
+
+	*state = raw;
+	return 0;
+}
+
+static u32 ssam_kip_sw_notif(struct ssam_event_notifier *nf, const struct ssam_event *event)
+{
+	struct ssam_tablet_sw *sw = container_of(nf, struct ssam_tablet_sw, notif);
+
+	if (event->command_id != SSAM_EVENT_KIP_CID_COVER_STATE_CHANGED)
+		return 0;	/* Return "unhandled". */
+
+	if (event->length < 1)
+		dev_warn(&sw->sdev->dev, "unexpected payload size: %u\n", event->length);
+
+	schedule_work(&sw->update_work);
+	return SSAM_NOTIF_HANDLED;
+}
+
+static const struct ssam_tablet_sw_desc ssam_kip_sw_desc = {
+	.dev = {
+		.name = "Microsoft Surface KIP Tablet Mode Switch",
+		.phys = "ssam/01:0e:01:00:01/input0",
+	},
+	.ops = {
+		.notify = ssam_kip_sw_notif,
+		.get_state = ssam_kip_get_cover_state,
+		.state_name = ssam_kip_cover_state_name,
+		.state_is_tablet_mode = ssam_kip_cover_state_is_tablet_mode,
+	},
+	.event = {
+		.reg = SSAM_EVENT_REGISTRY_SAM,
+		.id = {
+			.target_category = SSAM_SSH_TC_KIP,
+			.instance = 0,
+		},
+		.mask = SSAM_EVENT_MASK_TARGET,
+	},
+};
+
+
+/* -- SSAM POS tablet switch implementation. -------------------------------- */
+
+static bool tablet_mode_in_slate_state = true;
+module_param(tablet_mode_in_slate_state, bool, 0644);
+MODULE_PARM_DESC(tablet_mode_in_slate_state, "Enable tablet mode in slate device posture, default is 'true'");
+
+#define SSAM_EVENT_POS_CID_POSTURE_CHANGED	0x03
+#define SSAM_POS_MAX_SOURCES			4
+
+enum ssam_pos_state {
+	SSAM_POS_POSTURE_LID_CLOSED = 0x00,
+	SSAM_POS_POSTURE_LAPTOP     = 0x01,
+	SSAM_POS_POSTURE_SLATE      = 0x02,
+	SSAM_POS_POSTURE_TABLET     = 0x03,
+};
+
+struct ssam_sources_list {
+	__le32 count;
+	__le32 id[SSAM_POS_MAX_SOURCES];
+} __packed;
+
+static const char *ssam_pos_state_name(struct ssam_tablet_sw *sw, u32 state)
+{
+	switch (state) {
+	case SSAM_POS_POSTURE_LID_CLOSED:
+		return "closed";
+
+	case SSAM_POS_POSTURE_LAPTOP:
+		return "laptop";
+
+	case SSAM_POS_POSTURE_SLATE:
+		return "slate";
+
+	case SSAM_POS_POSTURE_TABLET:
+		return "tablet";
+
+	default:
+		dev_warn(&sw->sdev->dev, "unknown device posture: %u\n", state);
+		return "<unknown>";
+	}
+}
+
+static bool ssam_pos_state_is_tablet_mode(struct ssam_tablet_sw *sw, u32 state)
+{
+	switch (state) {
+	case SSAM_POS_POSTURE_LAPTOP:
+	case SSAM_POS_POSTURE_LID_CLOSED:
+		return false;
+
+	case SSAM_POS_POSTURE_SLATE:
+		return tablet_mode_in_slate_state;
+
+	case SSAM_POS_POSTURE_TABLET:
+		return true;
+
+	default:
+		dev_warn(&sw->sdev->dev, "unknown device posture: %u\n", state);
+		return true;
+	}
+}
+
+static int ssam_pos_get_sources_list(struct ssam_tablet_sw *sw, struct ssam_sources_list *sources)
+{
+	struct ssam_request rqst;
+	struct ssam_response rsp;
+	int status;
+
+	rqst.target_category = SSAM_SSH_TC_POS;
+	rqst.target_id = 0x01;
+	rqst.command_id = 0x01;
+	rqst.instance_id = 0x00;
+	rqst.flags = SSAM_REQUEST_HAS_RESPONSE;
+	rqst.length = 0;
+	rqst.payload = NULL;
+
+	rsp.capacity = sizeof(*sources);
+	rsp.length = 0;
+	rsp.pointer = (u8 *)sources;
+
+	status = ssam_retry(ssam_request_sync_onstack, sw->sdev->ctrl, &rqst, &rsp, 0);
+	if (status)
+		return status;
+
+	/* We need at least the 'sources->count' field. */
+	if (rsp.length < sizeof(__le32)) {
+		dev_err(&sw->sdev->dev, "received source list response is too small\n");
+		return -EPROTO;
+	}
+
+	/* Make sure 'sources->count' matches with the response length. */
+	if (get_unaligned_le32(&sources->count) * sizeof(__le32) + sizeof(__le32) != rsp.length) {
+		dev_err(&sw->sdev->dev, "mismatch between number of sources and response size\n");
+		return -EPROTO;
+	}
+
+	return 0;
+}
+
+static int ssam_pos_get_source(struct ssam_tablet_sw *sw, u32 *source_id)
+{
+	struct ssam_sources_list sources = {};
+	int status;
+
+	status = ssam_pos_get_sources_list(sw, &sources);
+	if (status)
+		return status;
+
+	if (sources.count == 0) {
+		dev_err(&sw->sdev->dev, "no posture sources found\n");
+		return -ENODEV;
+	}
+
+	/*
+	 * We currently don't know what to do with more than one posture
+	 * source. At the moment, only one source seems to be used/provided.
+	 * The WARN_ON() here should hopefully let us know quickly once there
+	 * is a device that provides multiple sources, at which point we can
+	 * then try to figure out how to handle them.
+	 */
+	WARN_ON(sources.count > 1);
+
+	*source_id = get_unaligned_le32(&sources.id[0]);
+	return 0;
+}
+
+SSAM_DEFINE_SYNC_REQUEST_WR(__ssam_pos_get_posture_for_source, __le32, __le32, {
+	.target_category = SSAM_SSH_TC_POS,
+	.target_id       = 0x01,
+	.command_id      = 0x02,
+	.instance_id     = 0x00,
+});
+
+static int ssam_pos_get_posture_for_source(struct ssam_tablet_sw *sw, u32 source_id, u32 *posture)
+{
+	__le32 source_le = cpu_to_le32(source_id);
+	__le32 rspval_le = 0;
+	int status;
+
+	status = ssam_retry(__ssam_pos_get_posture_for_source, sw->sdev->ctrl,
+			    &source_le, &rspval_le);
+	if (status)
+		return status;
+
+	*posture = le32_to_cpu(rspval_le);
+	return 0;
+}
+
+static int ssam_pos_get_posture(struct ssam_tablet_sw *sw, u32 *state)
+{
+	u32 source_id;
+	int status;
+
+	status = ssam_pos_get_source(sw, &source_id);
+	if (status) {
+		dev_err(&sw->sdev->dev, "failed to get posture source ID: %d\n", status);
+		return status;
+	}
+
+	status = ssam_pos_get_posture_for_source(sw, source_id, state);
+	if (status) {
+		dev_err(&sw->sdev->dev, "failed to get posture value for source %u: %d\n",
+			source_id, status);
+		return status;
+	}
+
+	return 0;
+}
+
+static u32 ssam_pos_sw_notif(struct ssam_event_notifier *nf, const struct ssam_event *event)
+{
+	struct ssam_tablet_sw *sw = container_of(nf, struct ssam_tablet_sw, notif);
+
+	if (event->command_id != SSAM_EVENT_POS_CID_POSTURE_CHANGED)
+		return 0;	/* Return "unhandled". */
+
+	if (event->length != sizeof(__le32) * 3)
+		dev_warn(&sw->sdev->dev, "unexpected payload size: %u\n", event->length);
+
+	schedule_work(&sw->update_work);
+	return SSAM_NOTIF_HANDLED;
+}
+
+static const struct ssam_tablet_sw_desc ssam_pos_sw_desc = {
+	.dev = {
+		.name = "Microsoft Surface POS Tablet Mode Switch",
+		.phys = "ssam/01:26:01:00:01/input0",
+	},
+	.ops = {
+		.notify = ssam_pos_sw_notif,
+		.get_state = ssam_pos_get_posture,
+		.state_name = ssam_pos_state_name,
+		.state_is_tablet_mode = ssam_pos_state_is_tablet_mode,
+	},
+	.event = {
+		.reg = SSAM_EVENT_REGISTRY_SAM,
+		.id = {
+			.target_category = SSAM_SSH_TC_POS,
+			.instance = 0,
+		},
+		.mask = SSAM_EVENT_MASK_TARGET,
+	},
+};
+
+
+/* -- Driver registration. -------------------------------------------------- */
+
+static const struct ssam_device_id ssam_tablet_sw_match[] = {
+	{ SSAM_SDEV(KIP, 0x01, 0x00, 0x01), (unsigned long)&ssam_kip_sw_desc },
+	{ SSAM_SDEV(POS, 0x01, 0x00, 0x01), (unsigned long)&ssam_pos_sw_desc },
+	{ },
+};
+MODULE_DEVICE_TABLE(ssam, ssam_tablet_sw_match);
+
+static struct ssam_device_driver ssam_tablet_sw_driver = {
+	.probe = ssam_tablet_sw_probe,
+	.remove = ssam_tablet_sw_remove,
+	.match_table = ssam_tablet_sw_match,
+	.driver = {
+		.name = "surface_aggregator_tablet_mode_switch",
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+		.pm = &ssam_tablet_sw_pm_ops,
+	},
+};
+module_ssam_device_driver(ssam_tablet_sw_driver);
+
+MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
+MODULE_DESCRIPTION("Tablet mode switch driver for Surface devices using the Surface Aggregator Module");
+MODULE_LICENSE("GPL");
-- 
2.38.0

From f4cb665baca13f087ffa41e999f61031b44315da Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 24 Jun 2022 20:36:41 +0200
Subject: [PATCH] platform/surface: aggregator_registry: Add support for tablet
 mode switch on Surface Pro 8

Add a KIP subsystem tablet-mode switch device for the Surface Pro 8.
The respective driver for this device provides SW_TABLET_MODE input
events for user-space based on the state of the keyboard cover (e.g.
detached, folded-back, normal/laptop mode).

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220624183642.910893-4-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 drivers/platform/surface/surface_aggregator_registry.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 3b1310d61a24..6994168ee898 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -77,6 +77,12 @@ static const struct software_node ssam_node_tmp_pprof = {
 	.parent = &ssam_node_root,
 };
 
+/* Tablet-mode switch via KIP subsystem. */
+static const struct software_node ssam_node_kip_tablet_switch = {
+	.name = "ssam:01:0e:01:00:01",
+	.parent = &ssam_node_root,
+};
+
 /* DTX / detachment-system device (Surface Book 3). */
 static const struct software_node ssam_node_bas_dtx = {
 	.name = "ssam:01:11:01:00:00",
@@ -264,11 +270,11 @@ static const struct software_node *ssam_node_group_sp8[] = {
 	&ssam_node_bat_ac,
 	&ssam_node_bat_main,
 	&ssam_node_tmp_pprof,
+	&ssam_node_kip_tablet_switch,
 	&ssam_node_hid_kip_keyboard,
 	&ssam_node_hid_kip_penstash,
 	&ssam_node_hid_kip_touchpad,
 	&ssam_node_hid_kip_iid5,
-	/* TODO: Add support for tablet mode switch. */
 	NULL,
 };
 
-- 
2.38.0

From f648e64b4ea98a52495f8e7382605d3c99ffbea0 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 24 Jun 2022 20:36:42 +0200
Subject: [PATCH] platform/surface: aggregator_registry: Add support for tablet
 mode switch on Surface Laptop Studio

Add a POS subsystem tablet-mode switch device for the Surface Laptop
Studio. The respective driver for this device provides SW_TABLET_MODE
input events for user-space based on the posture of the screen.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220624183642.910893-5-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 drivers/platform/surface/surface_aggregator_registry.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 6994168ee898..6e14dd18c7a7 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -191,6 +191,12 @@ static const struct software_node ssam_node_hid_kip_iid5 = {
 	.parent = &ssam_node_hub_kip,
 };
 
+/* Tablet-mode switch via POS subsystem. */
+static const struct software_node ssam_node_pos_tablet_switch = {
+	.name = "ssam:01:26:01:00:01",
+	.parent = &ssam_node_root,
+};
+
 /*
  * Devices for 5th- and 6th-generations models:
  * - Surface Book 2,
@@ -237,6 +243,7 @@ static const struct software_node *ssam_node_group_sls[] = {
 	&ssam_node_bat_ac,
 	&ssam_node_bat_main,
 	&ssam_node_tmp_pprof,
+	&ssam_node_pos_tablet_switch,
 	&ssam_node_hid_tid1_keyboard,
 	&ssam_node_hid_tid1_penstash,
 	&ssam_node_hid_tid1_touchpad,
-- 
2.38.0

From 246f11e41c786c82df2e816a3a94705784bc1b0f Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 24 Jun 2022 22:57:58 +0200
Subject: [PATCH] platform/surface: aggregator: Move device registry helper
 functions to core module

Move helper functions for client device registration to the core module.
This simplifies addition of future DT/OF support and also allows us to
split out the device hub drivers into their own module.

At the same time, also improve device node validation a bit by not
silently skipping devices with invalid device UID specifiers. Further,
ensure proper lifetime management for the firmware/software nodes
associated with the added devices.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220624205800.1355621-2-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 drivers/platform/surface/aggregator/bus.c     | 149 ++++++++++++++++--
 .../surface/surface_aggregator_registry.c     |  75 +--------
 include/linux/surface_aggregator/device.h     |  52 ++++++
 3 files changed, 187 insertions(+), 89 deletions(-)

diff --git a/drivers/platform/surface/aggregator/bus.c b/drivers/platform/surface/aggregator/bus.c
index abbbb5b08b07..e0b0381a2834 100644
--- a/drivers/platform/surface/aggregator/bus.c
+++ b/drivers/platform/surface/aggregator/bus.c
@@ -6,6 +6,7 @@
  */
 
 #include <linux/device.h>
+#include <linux/property.h>
 #include <linux/slab.h>
 
 #include <linux/surface_aggregator/controller.h>
@@ -14,6 +15,9 @@
 #include "bus.h"
 #include "controller.h"
 
+
+/* -- Device and bus functions. --------------------------------------------- */
+
 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
 			     char *buf)
 {
@@ -46,6 +50,7 @@ static void ssam_device_release(struct device *dev)
 	struct ssam_device *sdev = to_ssam_device(dev);
 
 	ssam_controller_put(sdev->ctrl);
+	fwnode_handle_put(sdev->dev.fwnode);
 	kfree(sdev);
 }
 
@@ -363,6 +368,134 @@ void ssam_device_driver_unregister(struct ssam_device_driver *sdrv)
 }
 EXPORT_SYMBOL_GPL(ssam_device_driver_unregister);
 
+
+/* -- Bus registration. ----------------------------------------------------- */
+
+/**
+ * ssam_bus_register() - Register and set-up the SSAM client device bus.
+ */
+int ssam_bus_register(void)
+{
+	return bus_register(&ssam_bus_type);
+}
+
+/**
+ * ssam_bus_unregister() - Unregister the SSAM client device bus.
+ */
+void ssam_bus_unregister(void)
+{
+	return bus_unregister(&ssam_bus_type);
+}
+
+
+/* -- Helpers for controller and hub devices. ------------------------------- */
+
+static int ssam_device_uid_from_string(const char *str, struct ssam_device_uid *uid)
+{
+	u8 d, tc, tid, iid, fn;
+	int n;
+
+	n = sscanf(str, "%hhx:%hhx:%hhx:%hhx:%hhx", &d, &tc, &tid, &iid, &fn);
+	if (n != 5)
+		return -EINVAL;
+
+	uid->domain = d;
+	uid->category = tc;
+	uid->target = tid;
+	uid->instance = iid;
+	uid->function = fn;
+
+	return 0;
+}
+
+static int ssam_get_uid_for_node(struct fwnode_handle *node, struct ssam_device_uid *uid)
+{
+	const char *str = fwnode_get_name(node);
+
+	/*
+	 * To simplify definitions of firmware nodes, we set the device name
+	 * based on the UID of the device, prefixed with "ssam:".
+	 */
+	if (strncmp(str, "ssam:", strlen("ssam:")) != 0)
+		return -ENODEV;
+
+	str += strlen("ssam:");
+	return ssam_device_uid_from_string(str, uid);
+}
+
+static int ssam_add_client_device(struct device *parent, struct ssam_controller *ctrl,
+				  struct fwnode_handle *node)
+{
+	struct ssam_device_uid uid;
+	struct ssam_device *sdev;
+	int status;
+
+	status = ssam_get_uid_for_node(node, &uid);
+	if (status)
+		return status;
+
+	sdev = ssam_device_alloc(ctrl, uid);
+	if (!sdev)
+		return -ENOMEM;
+
+	sdev->dev.parent = parent;
+	sdev->dev.fwnode = fwnode_handle_get(node);
+
+	status = ssam_device_add(sdev);
+	if (status)
+		ssam_device_put(sdev);
+
+	return status;
+}
+
+/**
+ * __ssam_register_clients() - Register client devices defined under the
+ * given firmware node as children of the given device.
+ * @parent: The parent device under which clients should be registered.
+ * @ctrl: The controller with which client should be registered.
+ * @node: The firmware node holding definitions of the devices to be added.
+ *
+ * Register all clients that have been defined as children of the given root
+ * firmware node as children of the given parent device. The respective child
+ * firmware nodes will be associated with the correspondingly created child
+ * devices.
+ *
+ * The given controller will be used to instantiate the new devices. See
+ * ssam_device_add() for details.
+ *
+ * Note that, generally, the use of either ssam_device_register_clients() or
+ * ssam_register_clients() should be preferred as they directly use the
+ * firmware node and/or controller associated with the given device. This
+ * function is only intended for use when different device specifications (e.g.
+ * ACPI and firmware nodes) need to be combined (as is done in the platform hub
+ * of the device registry).
+ *
+ * Return: Returns zero on success, nonzero on failure.
+ */
+int __ssam_register_clients(struct device *parent, struct ssam_controller *ctrl,
+			    struct fwnode_handle *node)
+{
+	struct fwnode_handle *child;
+	int status;
+
+	fwnode_for_each_child_node(node, child) {
+		/*
+		 * Try to add the device specified in the firmware node. If
+		 * this fails with -ENODEV, the node does not specify any SSAM
+		 * device, so ignore it and continue with the next one.
+		 */
+		status = ssam_add_client_device(parent, ctrl, child);
+		if (status && status != -ENODEV)
+			goto err;
+	}
+
+	return 0;
+err:
+	ssam_remove_clients(parent);
+	return status;
+}
+EXPORT_SYMBOL_GPL(__ssam_register_clients);
+
 static int ssam_remove_device(struct device *dev, void *_data)
 {
 	struct ssam_device *sdev = to_ssam_device(dev);
@@ -387,19 +520,3 @@ void ssam_remove_clients(struct device *dev)
 	device_for_each_child_reverse(dev, NULL, ssam_remove_device);
 }
 EXPORT_SYMBOL_GPL(ssam_remove_clients);
-
-/**
- * ssam_bus_register() - Register and set-up the SSAM client device bus.
- */
-int ssam_bus_register(void)
-{
-	return bus_register(&ssam_bus_type);
-}
-
-/**
- * ssam_bus_unregister() - Unregister the SSAM client device bus.
- */
-void ssam_bus_unregister(void)
-{
-	return bus_unregister(&ssam_bus_type);
-}
diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 6e14dd18c7a7..eb88021c208c 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -286,76 +286,6 @@ static const struct software_node *ssam_node_group_sp8[] = {
 };
 
 
-/* -- Device registry helper functions. ------------------------------------- */
-
-static int ssam_uid_from_string(const char *str, struct ssam_device_uid *uid)
-{
-	u8 d, tc, tid, iid, fn;
-	int n;
-
-	n = sscanf(str, "ssam:%hhx:%hhx:%hhx:%hhx:%hhx", &d, &tc, &tid, &iid, &fn);
-	if (n != 5)
-		return -EINVAL;
-
-	uid->domain = d;
-	uid->category = tc;
-	uid->target = tid;
-	uid->instance = iid;
-	uid->function = fn;
-
-	return 0;
-}
-
-static int ssam_hub_add_device(struct device *parent, struct ssam_controller *ctrl,
-			       struct fwnode_handle *node)
-{
-	struct ssam_device_uid uid;
-	struct ssam_device *sdev;
-	int status;
-
-	status = ssam_uid_from_string(fwnode_get_name(node), &uid);
-	if (status)
-		return status;
-
-	sdev = ssam_device_alloc(ctrl, uid);
-	if (!sdev)
-		return -ENOMEM;
-
-	sdev->dev.parent = parent;
-	sdev->dev.fwnode = node;
-
-	status = ssam_device_add(sdev);
-	if (status)
-		ssam_device_put(sdev);
-
-	return status;
-}
-
-static int ssam_hub_register_clients(struct device *parent, struct ssam_controller *ctrl,
-				     struct fwnode_handle *node)
-{
-	struct fwnode_handle *child;
-	int status;
-
-	fwnode_for_each_child_node(node, child) {
-		/*
-		 * Try to add the device specified in the firmware node. If
-		 * this fails with -EINVAL, the node does not specify any SSAM
-		 * device, so ignore it and continue with the next one.
-		 */
-
-		status = ssam_hub_add_device(parent, ctrl, child);
-		if (status && status != -EINVAL)
-			goto err;
-	}
-
-	return 0;
-err:
-	ssam_remove_clients(parent);
-	return status;
-}
-
-
 /* -- SSAM generic subsystem hub driver framework. -------------------------- */
 
 enum ssam_hub_state {
@@ -385,7 +315,6 @@ struct ssam_hub {
 static void ssam_hub_update_workfn(struct work_struct *work)
 {
 	struct ssam_hub *hub = container_of(work, struct ssam_hub, update_work.work);
-	struct fwnode_handle *node = dev_fwnode(&hub->sdev->dev);
 	enum ssam_hub_state state;
 	int status = 0;
 
@@ -425,7 +354,7 @@ static void ssam_hub_update_workfn(struct work_struct *work)
 	hub->state = state;
 
 	if (hub->state == SSAM_HUB_CONNECTED)
-		status = ssam_hub_register_clients(&hub->sdev->dev, hub->sdev->ctrl, node);
+		status = ssam_device_register_clients(hub->sdev);
 	else
 		ssam_remove_clients(&hub->sdev->dev);
 
@@ -772,7 +701,7 @@ static int ssam_platform_hub_probe(struct platform_device *pdev)
 
 	set_secondary_fwnode(&pdev->dev, root);
 
-	status = ssam_hub_register_clients(&pdev->dev, ctrl, root);
+	status = __ssam_register_clients(&pdev->dev, ctrl, root);
 	if (status) {
 		set_secondary_fwnode(&pdev->dev, NULL);
 		software_node_unregister_node_group(nodes);
diff --git a/include/linux/surface_aggregator/device.h b/include/linux/surface_aggregator/device.h
index 6cf7e80312d5..46c45d1b6368 100644
--- a/include/linux/surface_aggregator/device.h
+++ b/include/linux/surface_aggregator/device.h
@@ -15,6 +15,7 @@
 
 #include <linux/device.h>
 #include <linux/mod_devicetable.h>
+#include <linux/property.h>
 #include <linux/types.h>
 
 #include <linux/surface_aggregator/controller.h>
@@ -375,11 +376,62 @@ void ssam_device_driver_unregister(struct ssam_device_driver *d);
 /* -- Helpers for controller and hub devices. ------------------------------- */
 
 #ifdef CONFIG_SURFACE_AGGREGATOR_BUS
+
+int __ssam_register_clients(struct device *parent, struct ssam_controller *ctrl,
+			    struct fwnode_handle *node);
 void ssam_remove_clients(struct device *dev);
+
 #else /* CONFIG_SURFACE_AGGREGATOR_BUS */
+
+static inline int __ssam_register_clients(struct device *parent, struct ssam_controller *ctrl,
+					  struct fwnode_handle *node)
+{
+	return 0;
+}
+
 static inline void ssam_remove_clients(struct device *dev) {}
+
 #endif /* CONFIG_SURFACE_AGGREGATOR_BUS */
 
+/**
+ * ssam_register_clients() - Register all client devices defined under the
+ * given parent device.
+ * @dev: The parent device under which clients should be registered.
+ * @ctrl: The controller with which client should be registered.
+ *
+ * Register all clients that have via firmware nodes been defined as children
+ * of the given (parent) device. The respective child firmware nodes will be
+ * associated with the correspondingly created child devices.
+ *
+ * The given controller will be used to instantiate the new devices. See
+ * ssam_device_add() for details.
+ *
+ * Return: Returns zero on success, nonzero on failure.
+ */
+static inline int ssam_register_clients(struct device *dev, struct ssam_controller *ctrl)
+{
+	return __ssam_register_clients(dev, ctrl, dev_fwnode(dev));
+}
+
+/**
+ * ssam_device_register_clients() - Register all client devices defined under
+ * the given SSAM parent device.
+ * @sdev: The parent device under which clients should be registered.
+ *
+ * Register all clients that have via firmware nodes been defined as children
+ * of the given (parent) device. The respective child firmware nodes will be
+ * associated with the correspondingly created child devices.
+ *
+ * The controller used by the parent device will be used to instantiate the new
+ * devices. See ssam_device_add() for details.
+ *
+ * Return: Returns zero on success, nonzero on failure.
+ */
+static inline int ssam_device_register_clients(struct ssam_device *sdev)
+{
+	return ssam_register_clients(&sdev->dev, sdev->ctrl);
+}
+
 
 /* -- Helpers for client-device requests. ----------------------------------- */
 
-- 
2.38.0

From b864dfd5fa6a705d7ae5a13e79ac32ca67dec4a9 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 24 Jun 2022 22:57:59 +0200
Subject: [PATCH] platform/surface: aggregator: Move subsystem hub drivers to
 their own module

Split out subsystem device hub drivers into their own module. This
allows us to load the hub drivers separately from the registry, which
will help future DT/OF support.

While doing so, also remove a small bit of code duplication.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220624205800.1355621-3-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 MAINTAINERS                                   |   6 +
 drivers/platform/surface/Kconfig              |  35 +-
 drivers/platform/surface/Makefile             |   1 +
 .../platform/surface/surface_aggregator_hub.c | 371 ++++++++++++++++++
 .../surface/surface_aggregator_registry.c     | 371 +-----------------
 5 files changed, 410 insertions(+), 374 deletions(-)
 create mode 100644 drivers/platform/surface/surface_aggregator_hub.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 773eb8387f4a..55e80354a097 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -13376,6 +13376,12 @@ F:	include/linux/surface_acpi_notify.h
 F:	include/linux/surface_aggregator/
 F:	include/uapi/linux/surface_aggregator/
 
+MICROSOFT SURFACE SYSTEM AGGREGATOR HUB DRIVER
+M:	Maximilian Luz <luzmaximilian@gmail.com>
+L:	platform-driver-x86@vger.kernel.org
+S:	Maintained
+F:	drivers/platform/surface/surface_aggregator_hub.c
+
 MICROTEK X6 SCANNER
 M:	Oliver Neukum <oliver@neukum.org>
 S:	Maintained
diff --git a/drivers/platform/surface/Kconfig b/drivers/platform/surface/Kconfig
index b152e930cc84..b629e82af97c 100644
--- a/drivers/platform/surface/Kconfig
+++ b/drivers/platform/surface/Kconfig
@@ -72,18 +72,45 @@ config SURFACE_AGGREGATOR_CDEV
 	  The provided interface is intended for debugging and development only,
 	  and should not be used otherwise.
 
+config SURFACE_AGGREGATOR_HUB
+	tristate "Surface System Aggregator Module Subsystem Device Hubs"
+	depends on SURFACE_AGGREGATOR
+	depends on SURFACE_AGGREGATOR_BUS
+	help
+	  Device-hub drivers for Surface System Aggregator Module (SSAM) subsystem
+	  devices.
+
+	  Provides subsystem hub drivers which manage client devices on various
+	  SSAM subsystems. In some subsystems, notably the BAS subsystem managing
+	  devices contained in the base of the Surface Book 3 and the KIP subsystem
+	  managing type-cover devices in the Surface Pro 8 and Surface Pro X,
+	  devices can be (hot-)removed. Hub devices and drivers are required to
+	  manage these subdevices.
+
+	  Devices managed via these hubs are:
+	  - Battery/AC devices (Surface Book 3).
+	  - HID input devices (7th-generation and later models with detachable
+	    input devices).
+
+	  Select M (recommended) or Y here if you want support for the above
+	  mentioned devices on the corresponding Surface models. Without this
+	  module, the respective devices mentioned above will not be instantiated
+	  and thus any functionality provided by them will be missing, even when
+	  drivers for these devices are present. This module only provides the
+	  respective subsystem hubs. Both drivers and device specification (e.g.
+	  via the Surface Aggregator Registry) for these devices still need to be
+	  selected via other options.
+
 config SURFACE_AGGREGATOR_REGISTRY
 	tristate "Surface System Aggregator Module Device Registry"
 	depends on SURFACE_AGGREGATOR
 	depends on SURFACE_AGGREGATOR_BUS
 	help
-	  Device-registry and device-hubs for Surface System Aggregator Module
-	  (SSAM) devices.
+	  Device-registry for Surface System Aggregator Module (SSAM) devices.
 
 	  Provides a module and driver which act as a device-registry for SSAM
 	  client devices that cannot be detected automatically, e.g. via ACPI.
-	  Such devices are instead provided via this registry and attached via
-	  device hubs, also provided in this module.
+	  Such devices are instead provided and managed via this registry.
 
 	  Devices provided via this registry are:
 	  - Platform profile (performance-/cooling-mode) device (5th- and later
diff --git a/drivers/platform/surface/Makefile b/drivers/platform/surface/Makefile
index 18b27898543e..53344330939b 100644
--- a/drivers/platform/surface/Makefile
+++ b/drivers/platform/surface/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_SURFACE_3_POWER_OPREGION)	+= surface3_power.o
 obj-$(CONFIG_SURFACE_ACPI_NOTIFY)	+= surface_acpi_notify.o
 obj-$(CONFIG_SURFACE_AGGREGATOR)	+= aggregator/
 obj-$(CONFIG_SURFACE_AGGREGATOR_CDEV)	+= surface_aggregator_cdev.o
+obj-$(CONFIG_SURFACE_AGGREGATOR_HUB)	+= surface_aggregator_hub.o
 obj-$(CONFIG_SURFACE_AGGREGATOR_REGISTRY) += surface_aggregator_registry.o
 obj-$(CONFIG_SURFACE_AGGREGATOR_TABLET_SWITCH) += surface_aggregator_tabletsw.o
 obj-$(CONFIG_SURFACE_DTX)		+= surface_dtx.o
diff --git a/drivers/platform/surface/surface_aggregator_hub.c b/drivers/platform/surface/surface_aggregator_hub.c
new file mode 100644
index 000000000000..43061514be38
--- /dev/null
+++ b/drivers/platform/surface/surface_aggregator_hub.c
@@ -0,0 +1,371 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Driver for Surface System Aggregator Module (SSAM) subsystem device hubs.
+ *
+ * Provides a driver for SSAM subsystems device hubs. This driver performs
+ * instantiation of the devices managed by said hubs and takes care of
+ * (hot-)removal.
+ *
+ * Copyright (C) 2020-2022 Maximilian Luz <luzmaximilian@gmail.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/limits.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/workqueue.h>
+
+#include <linux/surface_aggregator/device.h>
+
+
+/* -- SSAM generic subsystem hub driver framework. -------------------------- */
+
+enum ssam_hub_state {
+	SSAM_HUB_UNINITIALIZED,		/* Only set during initialization. */
+	SSAM_HUB_CONNECTED,
+	SSAM_HUB_DISCONNECTED,
+};
+
+enum ssam_hub_flags {
+	SSAM_HUB_HOT_REMOVED,
+};
+
+struct ssam_hub;
+
+struct ssam_hub_ops {
+	int (*get_state)(struct ssam_hub *hub, enum ssam_hub_state *state);
+};
+
+struct ssam_hub {
+	struct ssam_device *sdev;
+
+	enum ssam_hub_state state;
+	unsigned long flags;
+
+	struct delayed_work update_work;
+	unsigned long connect_delay;
+
+	struct ssam_event_notifier notif;
+	struct ssam_hub_ops ops;
+};
+
+struct ssam_hub_desc {
+	struct {
+		struct ssam_event_registry reg;
+		struct ssam_event_id id;
+		enum ssam_event_mask mask;
+	} event;
+
+	struct {
+		u32 (*notify)(struct ssam_event_notifier *nf, const struct ssam_event *event);
+		int (*get_state)(struct ssam_hub *hub, enum ssam_hub_state *state);
+	} ops;
+
+	unsigned long connect_delay_ms;
+};
+
+static void ssam_hub_update_workfn(struct work_struct *work)
+{
+	struct ssam_hub *hub = container_of(work, struct ssam_hub, update_work.work);
+	enum ssam_hub_state state;
+	int status = 0;
+
+	status = hub->ops.get_state(hub, &state);
+	if (status)
+		return;
+
+	/*
+	 * There is a small possibility that hub devices were hot-removed and
+	 * re-added before we were able to remove them here. In that case, both
+	 * the state returned by get_state() and the state of the hub will
+	 * equal SSAM_HUB_CONNECTED and we would bail early below, which would
+	 * leave child devices without proper (re-)initialization and the
+	 * hot-remove flag set.
+	 *
+	 * Therefore, we check whether devices have been hot-removed via an
+	 * additional flag on the hub and, in this case, override the returned
+	 * hub state. In case of a missed disconnect (i.e. get_state returned
+	 * "connected"), we further need to re-schedule this work (with the
+	 * appropriate delay) as the actual connect work submission might have
+	 * been merged with this one.
+	 *
+	 * This then leads to one of two cases: Either we submit an unnecessary
+	 * work item (which will get ignored via either the queue or the state
+	 * checks) or, in the unlikely case that the work is actually required,
+	 * double the normal connect delay.
+	 */
+	if (test_and_clear_bit(SSAM_HUB_HOT_REMOVED, &hub->flags)) {
+		if (state == SSAM_HUB_CONNECTED)
+			schedule_delayed_work(&hub->update_work, hub->connect_delay);
+
+		state = SSAM_HUB_DISCONNECTED;
+	}
+
+	if (hub->state == state)
+		return;
+	hub->state = state;
+
+	if (hub->state == SSAM_HUB_CONNECTED)
+		status = ssam_device_register_clients(hub->sdev);
+	else
+		ssam_remove_clients(&hub->sdev->dev);
+
+	if (status)
+		dev_err(&hub->sdev->dev, "failed to update hub child devices: %d\n", status);
+}
+
+static int ssam_hub_mark_hot_removed(struct device *dev, void *_data)
+{
+	struct ssam_device *sdev = to_ssam_device(dev);
+
+	if (is_ssam_device(dev))
+		ssam_device_mark_hot_removed(sdev);
+
+	return 0;
+}
+
+static void ssam_hub_update(struct ssam_hub *hub, bool connected)
+{
+	unsigned long delay;
+
+	/* Mark devices as hot-removed before we remove any. */
+	if (!connected) {
+		set_bit(SSAM_HUB_HOT_REMOVED, &hub->flags);
+		device_for_each_child_reverse(&hub->sdev->dev, NULL, ssam_hub_mark_hot_removed);
+	}
+
+	/*
+	 * Delay update when the base/keyboard cover is being connected to give
+	 * devices/EC some time to set up.
+	 */
+	delay = connected ? hub->connect_delay : 0;
+
+	schedule_delayed_work(&hub->update_work, delay);
+}
+
+static int __maybe_unused ssam_hub_resume(struct device *dev)
+{
+	struct ssam_hub *hub = dev_get_drvdata(dev);
+
+	schedule_delayed_work(&hub->update_work, 0);
+	return 0;
+}
+static SIMPLE_DEV_PM_OPS(ssam_hub_pm_ops, NULL, ssam_hub_resume);
+
+static int ssam_hub_probe(struct ssam_device *sdev)
+{
+	const struct ssam_hub_desc *desc;
+	struct ssam_hub *hub;
+	int status;
+
+	desc = ssam_device_get_match_data(sdev);
+	if (!desc) {
+		WARN(1, "no driver match data specified");
+		return -EINVAL;
+	}
+
+	hub = devm_kzalloc(&sdev->dev, sizeof(*hub), GFP_KERNEL);
+	if (!hub)
+		return -ENOMEM;
+
+	hub->sdev = sdev;
+	hub->state = SSAM_HUB_UNINITIALIZED;
+
+	hub->notif.base.priority = INT_MAX;  /* This notifier should run first. */
+	hub->notif.base.fn = desc->ops.notify;
+	hub->notif.event.reg = desc->event.reg;
+	hub->notif.event.id = desc->event.id;
+	hub->notif.event.mask = desc->event.mask;
+	hub->notif.event.flags = SSAM_EVENT_SEQUENCED;
+
+	hub->connect_delay = msecs_to_jiffies(desc->connect_delay_ms);
+	hub->ops.get_state = desc->ops.get_state;
+
+	INIT_DELAYED_WORK(&hub->update_work, ssam_hub_update_workfn);
+
+	ssam_device_set_drvdata(sdev, hub);
+
+	status = ssam_device_notifier_register(sdev, &hub->notif);
+	if (status)
+		return status;
+
+	schedule_delayed_work(&hub->update_work, 0);
+	return 0;
+}
+
+static void ssam_hub_remove(struct ssam_device *sdev)
+{
+	struct ssam_hub *hub = ssam_device_get_drvdata(sdev);
+
+	ssam_device_notifier_unregister(sdev, &hub->notif);
+	cancel_delayed_work_sync(&hub->update_work);
+	ssam_remove_clients(&sdev->dev);
+}
+
+
+/* -- SSAM base-subsystem hub driver. --------------------------------------- */
+
+/*
+ * Some devices (especially battery) may need a bit of time to be fully usable
+ * after being (re-)connected. This delay has been determined via
+ * experimentation.
+ */
+#define SSAM_BASE_UPDATE_CONNECT_DELAY		2500
+
+SSAM_DEFINE_SYNC_REQUEST_R(ssam_bas_query_opmode, u8, {
+	.target_category = SSAM_SSH_TC_BAS,
+	.target_id       = 0x01,
+	.command_id      = 0x0d,
+	.instance_id     = 0x00,
+});
+
+#define SSAM_BAS_OPMODE_TABLET		0x00
+#define SSAM_EVENT_BAS_CID_CONNECTION	0x0c
+
+static int ssam_base_hub_query_state(struct ssam_hub *hub, enum ssam_hub_state *state)
+{
+	u8 opmode;
+	int status;
+
+	status = ssam_retry(ssam_bas_query_opmode, hub->sdev->ctrl, &opmode);
+	if (status < 0) {
+		dev_err(&hub->sdev->dev, "failed to query base state: %d\n", status);
+		return status;
+	}
+
+	if (opmode != SSAM_BAS_OPMODE_TABLET)
+		*state = SSAM_HUB_CONNECTED;
+	else
+		*state = SSAM_HUB_DISCONNECTED;
+
+	return 0;
+}
+
+static u32 ssam_base_hub_notif(struct ssam_event_notifier *nf, const struct ssam_event *event)
+{
+	struct ssam_hub *hub = container_of(nf, struct ssam_hub, notif);
+
+	if (event->command_id != SSAM_EVENT_BAS_CID_CONNECTION)
+		return 0;
+
+	if (event->length < 1) {
+		dev_err(&hub->sdev->dev, "unexpected payload size: %u\n", event->length);
+		return 0;
+	}
+
+	ssam_hub_update(hub, event->data[0]);
+
+	/*
+	 * Do not return SSAM_NOTIF_HANDLED: The event should be picked up and
+	 * consumed by the detachment system driver. We're just a (more or less)
+	 * silent observer.
+	 */
+	return 0;
+}
+
+static const struct ssam_hub_desc base_hub = {
+	.event = {
+		.reg = SSAM_EVENT_REGISTRY_SAM,
+		.id = {
+			.target_category = SSAM_SSH_TC_BAS,
+			.instance = 0,
+		},
+		.mask = SSAM_EVENT_MASK_NONE,
+	},
+	.ops = {
+		.notify = ssam_base_hub_notif,
+		.get_state = ssam_base_hub_query_state,
+	},
+	.connect_delay_ms = SSAM_BASE_UPDATE_CONNECT_DELAY,
+};
+
+
+/* -- SSAM KIP-subsystem hub driver. ---------------------------------------- */
+
+/*
+ * Some devices may need a bit of time to be fully usable after being
+ * (re-)connected. This delay has been determined via experimentation.
+ */
+#define SSAM_KIP_UPDATE_CONNECT_DELAY		250
+
+#define SSAM_EVENT_KIP_CID_CONNECTION		0x2c
+
+SSAM_DEFINE_SYNC_REQUEST_R(__ssam_kip_query_state, u8, {
+	.target_category = SSAM_SSH_TC_KIP,
+	.target_id       = 0x01,
+	.command_id      = 0x2c,
+	.instance_id     = 0x00,
+});
+
+static int ssam_kip_hub_query_state(struct ssam_hub *hub, enum ssam_hub_state *state)
+{
+	int status;
+	u8 connected;
+
+	status = ssam_retry(__ssam_kip_query_state, hub->sdev->ctrl, &connected);
+	if (status < 0) {
+		dev_err(&hub->sdev->dev, "failed to query KIP connection state: %d\n", status);
+		return status;
+	}
+
+	*state = connected ? SSAM_HUB_CONNECTED : SSAM_HUB_DISCONNECTED;
+	return 0;
+}
+
+static u32 ssam_kip_hub_notif(struct ssam_event_notifier *nf, const struct ssam_event *event)
+{
+	struct ssam_hub *hub = container_of(nf, struct ssam_hub, notif);
+
+	if (event->command_id != SSAM_EVENT_KIP_CID_CONNECTION)
+		return 0;	/* Return "unhandled". */
+
+	if (event->length < 1) {
+		dev_err(&hub->sdev->dev, "unexpected payload size: %u\n", event->length);
+		return 0;
+	}
+
+	ssam_hub_update(hub, event->data[0]);
+	return SSAM_NOTIF_HANDLED;
+}
+
+static const struct ssam_hub_desc kip_hub = {
+	.event = {
+		.reg = SSAM_EVENT_REGISTRY_SAM,
+		.id = {
+			.target_category = SSAM_SSH_TC_KIP,
+			.instance = 0,
+		},
+		.mask = SSAM_EVENT_MASK_TARGET,
+	},
+	.ops = {
+		.notify = ssam_kip_hub_notif,
+		.get_state = ssam_kip_hub_query_state,
+	},
+	.connect_delay_ms = SSAM_KIP_UPDATE_CONNECT_DELAY,
+};
+
+
+/* -- Driver registration. -------------------------------------------------- */
+
+static const struct ssam_device_id ssam_hub_match[] = {
+	{ SSAM_VDEV(HUB, 0x01, SSAM_SSH_TC_KIP, 0x00), (unsigned long)&kip_hub  },
+	{ SSAM_VDEV(HUB, 0x02, SSAM_SSH_TC_BAS, 0x00), (unsigned long)&base_hub },
+	{ }
+};
+MODULE_DEVICE_TABLE(ssam, ssam_hub_match);
+
+static struct ssam_device_driver ssam_subsystem_hub_driver = {
+	.probe = ssam_hub_probe,
+	.remove = ssam_hub_remove,
+	.match_table = ssam_hub_match,
+	.driver = {
+		.name = "surface_aggregator_subsystem_hub",
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+		.pm = &ssam_hub_pm_ops,
+	},
+};
+module_ssam_device_driver(ssam_subsystem_hub_driver);
+
+MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
+MODULE_DESCRIPTION("Subsystem device hub driver for Surface System Aggregator Module");
+MODULE_LICENSE("GPL");
diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index eb88021c208c..76dc9c4f108e 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -11,14 +11,11 @@
 
 #include <linux/acpi.h>
 #include <linux/kernel.h>
-#include <linux/limits.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/property.h>
 #include <linux/types.h>
-#include <linux/workqueue.h>
 
-#include <linux/surface_aggregator/controller.h>
 #include <linux/surface_aggregator/device.h>
 
 
@@ -286,335 +283,6 @@ static const struct software_node *ssam_node_group_sp8[] = {
 };
 
 
-/* -- SSAM generic subsystem hub driver framework. -------------------------- */
-
-enum ssam_hub_state {
-	SSAM_HUB_UNINITIALIZED,		/* Only set during initialization. */
-	SSAM_HUB_CONNECTED,
-	SSAM_HUB_DISCONNECTED,
-};
-
-enum ssam_hub_flags {
-	SSAM_HUB_HOT_REMOVED,
-};
-
-struct ssam_hub {
-	struct ssam_device *sdev;
-
-	enum ssam_hub_state state;
-	unsigned long flags;
-
-	struct delayed_work update_work;
-	unsigned long connect_delay;
-
-	struct ssam_event_notifier notif;
-
-	int (*get_state)(struct ssam_hub *hub, enum ssam_hub_state *state);
-};
-
-static void ssam_hub_update_workfn(struct work_struct *work)
-{
-	struct ssam_hub *hub = container_of(work, struct ssam_hub, update_work.work);
-	enum ssam_hub_state state;
-	int status = 0;
-
-	status = hub->get_state(hub, &state);
-	if (status)
-		return;
-
-	/*
-	 * There is a small possibility that hub devices were hot-removed and
-	 * re-added before we were able to remove them here. In that case, both
-	 * the state returned by get_state() and the state of the hub will
-	 * equal SSAM_HUB_CONNECTED and we would bail early below, which would
-	 * leave child devices without proper (re-)initialization and the
-	 * hot-remove flag set.
-	 *
-	 * Therefore, we check whether devices have been hot-removed via an
-	 * additional flag on the hub and, in this case, override the returned
-	 * hub state. In case of a missed disconnect (i.e. get_state returned
-	 * "connected"), we further need to re-schedule this work (with the
-	 * appropriate delay) as the actual connect work submission might have
-	 * been merged with this one.
-	 *
-	 * This then leads to one of two cases: Either we submit an unnecessary
-	 * work item (which will get ignored via either the queue or the state
-	 * checks) or, in the unlikely case that the work is actually required,
-	 * double the normal connect delay.
-	 */
-	if (test_and_clear_bit(SSAM_HUB_HOT_REMOVED, &hub->flags)) {
-		if (state == SSAM_HUB_CONNECTED)
-			schedule_delayed_work(&hub->update_work, hub->connect_delay);
-
-		state = SSAM_HUB_DISCONNECTED;
-	}
-
-	if (hub->state == state)
-		return;
-	hub->state = state;
-
-	if (hub->state == SSAM_HUB_CONNECTED)
-		status = ssam_device_register_clients(hub->sdev);
-	else
-		ssam_remove_clients(&hub->sdev->dev);
-
-	if (status)
-		dev_err(&hub->sdev->dev, "failed to update hub child devices: %d\n", status);
-}
-
-static int ssam_hub_mark_hot_removed(struct device *dev, void *_data)
-{
-	struct ssam_device *sdev = to_ssam_device(dev);
-
-	if (is_ssam_device(dev))
-		ssam_device_mark_hot_removed(sdev);
-
-	return 0;
-}
-
-static void ssam_hub_update(struct ssam_hub *hub, bool connected)
-{
-	unsigned long delay;
-
-	/* Mark devices as hot-removed before we remove any. */
-	if (!connected) {
-		set_bit(SSAM_HUB_HOT_REMOVED, &hub->flags);
-		device_for_each_child_reverse(&hub->sdev->dev, NULL, ssam_hub_mark_hot_removed);
-	}
-
-	/*
-	 * Delay update when the base/keyboard cover is being connected to give
-	 * devices/EC some time to set up.
-	 */
-	delay = connected ? hub->connect_delay : 0;
-
-	schedule_delayed_work(&hub->update_work, delay);
-}
-
-static int __maybe_unused ssam_hub_resume(struct device *dev)
-{
-	struct ssam_hub *hub = dev_get_drvdata(dev);
-
-	schedule_delayed_work(&hub->update_work, 0);
-	return 0;
-}
-static SIMPLE_DEV_PM_OPS(ssam_hub_pm_ops, NULL, ssam_hub_resume);
-
-static int ssam_hub_setup(struct ssam_device *sdev, struct ssam_hub *hub)
-{
-	int status;
-
-	hub->sdev = sdev;
-	hub->state = SSAM_HUB_UNINITIALIZED;
-
-	INIT_DELAYED_WORK(&hub->update_work, ssam_hub_update_workfn);
-
-	ssam_device_set_drvdata(sdev, hub);
-
-	status = ssam_device_notifier_register(sdev, &hub->notif);
-	if (status)
-		return status;
-
-	schedule_delayed_work(&hub->update_work, 0);
-	return 0;
-}
-
-static void ssam_hub_remove(struct ssam_device *sdev)
-{
-	struct ssam_hub *hub = ssam_device_get_drvdata(sdev);
-
-	ssam_device_notifier_unregister(sdev, &hub->notif);
-	cancel_delayed_work_sync(&hub->update_work);
-	ssam_remove_clients(&sdev->dev);
-}
-
-
-/* -- SSAM base-hub driver. ------------------------------------------------- */
-
-/*
- * Some devices (especially battery) may need a bit of time to be fully usable
- * after being (re-)connected. This delay has been determined via
- * experimentation.
- */
-#define SSAM_BASE_UPDATE_CONNECT_DELAY		msecs_to_jiffies(2500)
-
-SSAM_DEFINE_SYNC_REQUEST_R(ssam_bas_query_opmode, u8, {
-	.target_category = SSAM_SSH_TC_BAS,
-	.target_id       = 0x01,
-	.command_id      = 0x0d,
-	.instance_id     = 0x00,
-});
-
-#define SSAM_BAS_OPMODE_TABLET		0x00
-#define SSAM_EVENT_BAS_CID_CONNECTION	0x0c
-
-static int ssam_base_hub_query_state(struct ssam_hub *hub, enum ssam_hub_state *state)
-{
-	u8 opmode;
-	int status;
-
-	status = ssam_retry(ssam_bas_query_opmode, hub->sdev->ctrl, &opmode);
-	if (status < 0) {
-		dev_err(&hub->sdev->dev, "failed to query base state: %d\n", status);
-		return status;
-	}
-
-	if (opmode != SSAM_BAS_OPMODE_TABLET)
-		*state = SSAM_HUB_CONNECTED;
-	else
-		*state = SSAM_HUB_DISCONNECTED;
-
-	return 0;
-}
-
-static u32 ssam_base_hub_notif(struct ssam_event_notifier *nf, const struct ssam_event *event)
-{
-	struct ssam_hub *hub = container_of(nf, struct ssam_hub, notif);
-
-	if (event->command_id != SSAM_EVENT_BAS_CID_CONNECTION)
-		return 0;
-
-	if (event->length < 1) {
-		dev_err(&hub->sdev->dev, "unexpected payload size: %u\n", event->length);
-		return 0;
-	}
-
-	ssam_hub_update(hub, event->data[0]);
-
-	/*
-	 * Do not return SSAM_NOTIF_HANDLED: The event should be picked up and
-	 * consumed by the detachment system driver. We're just a (more or less)
-	 * silent observer.
-	 */
-	return 0;
-}
-
-static int ssam_base_hub_probe(struct ssam_device *sdev)
-{
-	struct ssam_hub *hub;
-
-	hub = devm_kzalloc(&sdev->dev, sizeof(*hub), GFP_KERNEL);
-	if (!hub)
-		return -ENOMEM;
-
-	hub->notif.base.priority = INT_MAX;  /* This notifier should run first. */
-	hub->notif.base.fn = ssam_base_hub_notif;
-	hub->notif.event.reg = SSAM_EVENT_REGISTRY_SAM;
-	hub->notif.event.id.target_category = SSAM_SSH_TC_BAS,
-	hub->notif.event.id.instance = 0,
-	hub->notif.event.mask = SSAM_EVENT_MASK_NONE;
-	hub->notif.event.flags = SSAM_EVENT_SEQUENCED;
-
-	hub->connect_delay = SSAM_BASE_UPDATE_CONNECT_DELAY;
-	hub->get_state = ssam_base_hub_query_state;
-
-	return ssam_hub_setup(sdev, hub);
-}
-
-static const struct ssam_device_id ssam_base_hub_match[] = {
-	{ SSAM_VDEV(HUB, 0x02, SSAM_SSH_TC_BAS, 0x00) },
-	{ },
-};
-
-static struct ssam_device_driver ssam_base_hub_driver = {
-	.probe = ssam_base_hub_probe,
-	.remove = ssam_hub_remove,
-	.match_table = ssam_base_hub_match,
-	.driver = {
-		.name = "surface_aggregator_base_hub",
-		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
-		.pm = &ssam_hub_pm_ops,
-	},
-};
-
-
-/* -- SSAM KIP-subsystem hub driver. ---------------------------------------- */
-
-/*
- * Some devices may need a bit of time to be fully usable after being
- * (re-)connected. This delay has been determined via experimentation.
- */
-#define SSAM_KIP_UPDATE_CONNECT_DELAY		msecs_to_jiffies(250)
-
-#define SSAM_EVENT_KIP_CID_CONNECTION		0x2c
-
-SSAM_DEFINE_SYNC_REQUEST_R(__ssam_kip_get_connection_state, u8, {
-	.target_category = SSAM_SSH_TC_KIP,
-	.target_id       = 0x01,
-	.command_id      = 0x2c,
-	.instance_id     = 0x00,
-});
-
-static int ssam_kip_get_connection_state(struct ssam_hub *hub, enum ssam_hub_state *state)
-{
-	int status;
-	u8 connected;
-
-	status = ssam_retry(__ssam_kip_get_connection_state, hub->sdev->ctrl, &connected);
-	if (status < 0) {
-		dev_err(&hub->sdev->dev, "failed to query KIP connection state: %d\n", status);
-		return status;
-	}
-
-	*state = connected ? SSAM_HUB_CONNECTED : SSAM_HUB_DISCONNECTED;
-	return 0;
-}
-
-static u32 ssam_kip_hub_notif(struct ssam_event_notifier *nf, const struct ssam_event *event)
-{
-	struct ssam_hub *hub = container_of(nf, struct ssam_hub, notif);
-
-	if (event->command_id != SSAM_EVENT_KIP_CID_CONNECTION)
-		return 0;	/* Return "unhandled". */
-
-	if (event->length < 1) {
-		dev_err(&hub->sdev->dev, "unexpected payload size: %u\n", event->length);
-		return 0;
-	}
-
-	ssam_hub_update(hub, event->data[0]);
-	return SSAM_NOTIF_HANDLED;
-}
-
-static int ssam_kip_hub_probe(struct ssam_device *sdev)
-{
-	struct ssam_hub *hub;
-
-	hub = devm_kzalloc(&sdev->dev, sizeof(*hub), GFP_KERNEL);
-	if (!hub)
-		return -ENOMEM;
-
-	hub->notif.base.priority = INT_MAX;  /* This notifier should run first. */
-	hub->notif.base.fn = ssam_kip_hub_notif;
-	hub->notif.event.reg = SSAM_EVENT_REGISTRY_SAM;
-	hub->notif.event.id.target_category = SSAM_SSH_TC_KIP,
-	hub->notif.event.id.instance = 0,
-	hub->notif.event.mask = SSAM_EVENT_MASK_TARGET;
-	hub->notif.event.flags = SSAM_EVENT_SEQUENCED;
-
-	hub->connect_delay = SSAM_KIP_UPDATE_CONNECT_DELAY;
-	hub->get_state = ssam_kip_get_connection_state;
-
-	return ssam_hub_setup(sdev, hub);
-}
-
-static const struct ssam_device_id ssam_kip_hub_match[] = {
-	{ SSAM_VDEV(HUB, 0x01, SSAM_SSH_TC_KIP, 0x00) },
-	{ },
-};
-
-static struct ssam_device_driver ssam_kip_hub_driver = {
-	.probe = ssam_kip_hub_probe,
-	.remove = ssam_hub_remove,
-	.match_table = ssam_kip_hub_match,
-	.driver = {
-		.name = "surface_kip_hub",
-		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
-		.pm = &ssam_hub_pm_ops,
-	},
-};
-
-
 /* -- SSAM platform/meta-hub driver. ---------------------------------------- */
 
 static const struct acpi_device_id ssam_platform_hub_match[] = {
@@ -730,44 +398,7 @@ static struct platform_driver ssam_platform_hub_driver = {
 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
 	},
 };
-
-
-/* -- Module initialization. ------------------------------------------------ */
-
-static int __init ssam_device_hub_init(void)
-{
-	int status;
-
-	status = platform_driver_register(&ssam_platform_hub_driver);
-	if (status)
-		goto err_platform;
-
-	status = ssam_device_driver_register(&ssam_base_hub_driver);
-	if (status)
-		goto err_base;
-
-	status = ssam_device_driver_register(&ssam_kip_hub_driver);
-	if (status)
-		goto err_kip;
-
-	return 0;
-
-err_kip:
-	ssam_device_driver_unregister(&ssam_base_hub_driver);
-err_base:
-	platform_driver_unregister(&ssam_platform_hub_driver);
-err_platform:
-	return status;
-}
-module_init(ssam_device_hub_init);
-
-static void __exit ssam_device_hub_exit(void)
-{
-	ssam_device_driver_unregister(&ssam_kip_hub_driver);
-	ssam_device_driver_unregister(&ssam_base_hub_driver);
-	platform_driver_unregister(&ssam_platform_hub_driver);
-}
-module_exit(ssam_device_hub_exit);
+module_platform_driver(ssam_platform_hub_driver);
 
 MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
 MODULE_DESCRIPTION("Device-registry for Surface System Aggregator Module");
-- 
2.38.0

From 7724d8aff10451320a984da1e036e6287d31d885 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 24 Jun 2022 22:58:00 +0200
Subject: [PATCH] platform/surface: Update copyright year of various drivers

Update the copyright of various Surface drivers to the current year.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220624205800.1355621-4-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 drivers/platform/surface/aggregator/Kconfig             | 2 +-
 drivers/platform/surface/aggregator/Makefile            | 2 +-
 drivers/platform/surface/aggregator/bus.c               | 2 +-
 drivers/platform/surface/aggregator/bus.h               | 2 +-
 drivers/platform/surface/aggregator/controller.c        | 2 +-
 drivers/platform/surface/aggregator/controller.h        | 2 +-
 drivers/platform/surface/aggregator/core.c              | 2 +-
 drivers/platform/surface/aggregator/ssh_msgb.h          | 2 +-
 drivers/platform/surface/aggregator/ssh_packet_layer.c  | 2 +-
 drivers/platform/surface/aggregator/ssh_packet_layer.h  | 2 +-
 drivers/platform/surface/aggregator/ssh_parser.c        | 2 +-
 drivers/platform/surface/aggregator/ssh_parser.h        | 2 +-
 drivers/platform/surface/aggregator/ssh_request_layer.c | 2 +-
 drivers/platform/surface/aggregator/ssh_request_layer.h | 2 +-
 drivers/platform/surface/aggregator/trace.h             | 2 +-
 drivers/platform/surface/surface_acpi_notify.c          | 2 +-
 drivers/platform/surface/surface_aggregator_cdev.c      | 2 +-
 drivers/platform/surface/surface_aggregator_registry.c  | 2 +-
 drivers/platform/surface/surface_dtx.c                  | 2 +-
 drivers/platform/surface/surface_gpe.c                  | 2 +-
 drivers/platform/surface/surface_hotplug.c              | 2 +-
 drivers/platform/surface/surface_platform_profile.c     | 2 +-
 22 files changed, 22 insertions(+), 22 deletions(-)

diff --git a/drivers/platform/surface/aggregator/Kconfig b/drivers/platform/surface/aggregator/Kconfig
index cab020324256..c114f9dd5fe1 100644
--- a/drivers/platform/surface/aggregator/Kconfig
+++ b/drivers/platform/surface/aggregator/Kconfig
@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0+
-# Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+# Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
 
 menuconfig SURFACE_AGGREGATOR
 	tristate "Microsoft Surface System Aggregator Module Subsystem and Drivers"
diff --git a/drivers/platform/surface/aggregator/Makefile b/drivers/platform/surface/aggregator/Makefile
index c0d550eda5cd..fdf664a217f9 100644
--- a/drivers/platform/surface/aggregator/Makefile
+++ b/drivers/platform/surface/aggregator/Makefile
@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0+
-# Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+# Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
 
 # For include/trace/define_trace.h to include trace.h
 CFLAGS_core.o = -I$(src)
diff --git a/drivers/platform/surface/aggregator/bus.c b/drivers/platform/surface/aggregator/bus.c
index e0b0381a2834..de539938896e 100644
--- a/drivers/platform/surface/aggregator/bus.c
+++ b/drivers/platform/surface/aggregator/bus.c
@@ -2,7 +2,7 @@
 /*
  * Surface System Aggregator Module bus and device integration.
  *
- * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #include <linux/device.h>
diff --git a/drivers/platform/surface/aggregator/bus.h b/drivers/platform/surface/aggregator/bus.h
index 6964ee84e79c..5b4dbf21906c 100644
--- a/drivers/platform/surface/aggregator/bus.h
+++ b/drivers/platform/surface/aggregator/bus.h
@@ -2,7 +2,7 @@
 /*
  * Surface System Aggregator Module bus and device integration.
  *
- * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #ifndef _SURFACE_AGGREGATOR_BUS_H
diff --git a/drivers/platform/surface/aggregator/controller.c b/drivers/platform/surface/aggregator/controller.c
index 6de834b52b63..43e765199137 100644
--- a/drivers/platform/surface/aggregator/controller.c
+++ b/drivers/platform/surface/aggregator/controller.c
@@ -2,7 +2,7 @@
 /*
  * Main SSAM/SSH controller structure and functionality.
  *
- * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #include <linux/acpi.h>
diff --git a/drivers/platform/surface/aggregator/controller.h b/drivers/platform/surface/aggregator/controller.h
index a0963c3562ff..f0d987abc51e 100644
--- a/drivers/platform/surface/aggregator/controller.h
+++ b/drivers/platform/surface/aggregator/controller.h
@@ -2,7 +2,7 @@
 /*
  * Main SSAM/SSH controller structure and functionality.
  *
- * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #ifndef _SURFACE_AGGREGATOR_CONTROLLER_H
diff --git a/drivers/platform/surface/aggregator/core.c b/drivers/platform/surface/aggregator/core.c
index a62c5dfe42d6..1a6373dea109 100644
--- a/drivers/platform/surface/aggregator/core.c
+++ b/drivers/platform/surface/aggregator/core.c
@@ -7,7 +7,7 @@
  * Handles communication via requests as well as enabling, disabling, and
  * relaying of events.
  *
- * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #include <linux/acpi.h>
diff --git a/drivers/platform/surface/aggregator/ssh_msgb.h b/drivers/platform/surface/aggregator/ssh_msgb.h
index e562958ffdf0..f3ecad92eefd 100644
--- a/drivers/platform/surface/aggregator/ssh_msgb.h
+++ b/drivers/platform/surface/aggregator/ssh_msgb.h
@@ -2,7 +2,7 @@
 /*
  * SSH message builder functions.
  *
- * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #ifndef _SURFACE_AGGREGATOR_SSH_MSGB_H
diff --git a/drivers/platform/surface/aggregator/ssh_packet_layer.c b/drivers/platform/surface/aggregator/ssh_packet_layer.c
index 8a4451c1ffe5..6748fe4ac5d5 100644
--- a/drivers/platform/surface/aggregator/ssh_packet_layer.c
+++ b/drivers/platform/surface/aggregator/ssh_packet_layer.c
@@ -2,7 +2,7 @@
 /*
  * SSH packet transport layer.
  *
- * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #include <asm/unaligned.h>
diff --git a/drivers/platform/surface/aggregator/ssh_packet_layer.h b/drivers/platform/surface/aggregator/ssh_packet_layer.h
index 2eb329f0b91a..64633522f971 100644
--- a/drivers/platform/surface/aggregator/ssh_packet_layer.h
+++ b/drivers/platform/surface/aggregator/ssh_packet_layer.h
@@ -2,7 +2,7 @@
 /*
  * SSH packet transport layer.
  *
- * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #ifndef _SURFACE_AGGREGATOR_SSH_PACKET_LAYER_H
diff --git a/drivers/platform/surface/aggregator/ssh_parser.c b/drivers/platform/surface/aggregator/ssh_parser.c
index b77912f8f13b..a6f668694365 100644
--- a/drivers/platform/surface/aggregator/ssh_parser.c
+++ b/drivers/platform/surface/aggregator/ssh_parser.c
@@ -2,7 +2,7 @@
 /*
  * SSH message parser.
  *
- * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #include <asm/unaligned.h>
diff --git a/drivers/platform/surface/aggregator/ssh_parser.h b/drivers/platform/surface/aggregator/ssh_parser.h
index 3bd6e180fd16..801d8fa69fb5 100644
--- a/drivers/platform/surface/aggregator/ssh_parser.h
+++ b/drivers/platform/surface/aggregator/ssh_parser.h
@@ -2,7 +2,7 @@
 /*
  * SSH message parser.
  *
- * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #ifndef _SURFACE_AGGREGATOR_SSH_PARSER_H
diff --git a/drivers/platform/surface/aggregator/ssh_request_layer.c b/drivers/platform/surface/aggregator/ssh_request_layer.c
index 790f7f0eee98..f5565570f16c 100644
--- a/drivers/platform/surface/aggregator/ssh_request_layer.c
+++ b/drivers/platform/surface/aggregator/ssh_request_layer.c
@@ -2,7 +2,7 @@
 /*
  * SSH request transport layer.
  *
- * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #include <asm/unaligned.h>
diff --git a/drivers/platform/surface/aggregator/ssh_request_layer.h b/drivers/platform/surface/aggregator/ssh_request_layer.h
index 9c3cbae2d4bd..4e387a031351 100644
--- a/drivers/platform/surface/aggregator/ssh_request_layer.h
+++ b/drivers/platform/surface/aggregator/ssh_request_layer.h
@@ -2,7 +2,7 @@
 /*
  * SSH request transport layer.
  *
- * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #ifndef _SURFACE_AGGREGATOR_SSH_REQUEST_LAYER_H
diff --git a/drivers/platform/surface/aggregator/trace.h b/drivers/platform/surface/aggregator/trace.h
index cc9e73fbc18e..2a2c17771d01 100644
--- a/drivers/platform/surface/aggregator/trace.h
+++ b/drivers/platform/surface/aggregator/trace.h
@@ -2,7 +2,7 @@
 /*
  * Trace points for SSAM/SSH.
  *
- * Copyright (C) 2020-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2020-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #undef TRACE_SYSTEM
diff --git a/drivers/platform/surface/surface_acpi_notify.c b/drivers/platform/surface/surface_acpi_notify.c
index c0e12f0b9b79..44e317970557 100644
--- a/drivers/platform/surface/surface_acpi_notify.c
+++ b/drivers/platform/surface/surface_acpi_notify.c
@@ -8,7 +8,7 @@
  * notifications sent from ACPI via the SAN interface by providing them to any
  * registered external driver.
  *
- * Copyright (C) 2019-2020 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #include <asm/unaligned.h>
diff --git a/drivers/platform/surface/surface_aggregator_cdev.c b/drivers/platform/surface/surface_aggregator_cdev.c
index 30fb50fde450..492c82e69182 100644
--- a/drivers/platform/surface/surface_aggregator_cdev.c
+++ b/drivers/platform/surface/surface_aggregator_cdev.c
@@ -3,7 +3,7 @@
  * Provides user-space access to the SSAM EC via the /dev/surface/aggregator
  * misc device. Intended for debugging and development.
  *
- * Copyright (C) 2020-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2020-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #include <linux/fs.h>
diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 76dc9c4f108e..93ab62eb393d 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -6,7 +6,7 @@
  * cannot be auto-detected. Provides device-hubs and performs instantiation
  * for these devices.
  *
- * Copyright (C) 2020-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2020-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #include <linux/acpi.h>
diff --git a/drivers/platform/surface/surface_dtx.c b/drivers/platform/surface/surface_dtx.c
index 1203b9a82993..ed36944467f9 100644
--- a/drivers/platform/surface/surface_dtx.c
+++ b/drivers/platform/surface/surface_dtx.c
@@ -8,7 +8,7 @@
  * acknowledge (to speed things up), abort (e.g. in case the dGPU is still in
  * use), or request detachment via user-space.
  *
- * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #include <linux/fs.h>
diff --git a/drivers/platform/surface/surface_gpe.c b/drivers/platform/surface/surface_gpe.c
index ec66fde28e75..27365cbe1ee9 100644
--- a/drivers/platform/surface/surface_gpe.c
+++ b/drivers/platform/surface/surface_gpe.c
@@ -4,7 +4,7 @@
  * properly configuring the respective GPEs. Required for wakeup via lid on
  * newer Intel-based Microsoft Surface devices.
  *
- * Copyright (C) 2020 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2020-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
diff --git a/drivers/platform/surface/surface_hotplug.c b/drivers/platform/surface/surface_hotplug.c
index cfcc15cfbacb..f004a2495201 100644
--- a/drivers/platform/surface/surface_hotplug.c
+++ b/drivers/platform/surface/surface_hotplug.c
@@ -10,7 +10,7 @@
  * Event signaling is handled via ACPI, which will generate the appropriate
  * device-check notifications to be picked up by the PCIe hot-plug driver.
  *
- * Copyright (C) 2019-2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #include <linux/acpi.h>
diff --git a/drivers/platform/surface/surface_platform_profile.c b/drivers/platform/surface/surface_platform_profile.c
index 6373d3b5eb7f..fbf2e11fd6ce 100644
--- a/drivers/platform/surface/surface_platform_profile.c
+++ b/drivers/platform/surface/surface_platform_profile.c
@@ -3,7 +3,7 @@
  * Surface Platform Profile / Performance Mode driver for Surface System
  * Aggregator Module (thermal subsystem).
  *
- * Copyright (C) 2021 Maximilian Luz <luzmaximilian@gmail.com>
+ * Copyright (C) 2021-2022 Maximilian Luz <luzmaximilian@gmail.com>
  */
 
 #include <asm/unaligned.h>
-- 
2.38.0

From c438c4623613abea111de98c2b31e5485ad3ebfa Mon Sep 17 00:00:00 2001
From: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Date: Wed, 13 Jul 2022 06:09:16 +0200
Subject: [PATCH] MAINTAINERS: repair file entry in MICROSOFT SURFACE
 AGGREGATOR TABLET-MODE SWITCH

Commit 9f794056db5b ("platform/surface: Add KIP/POS tablet-mode switch
driver") adds the section MICROSOFT SURFACE AGGREGATOR TABLET-MODE SWITCH
with a file entry, but the file that is added with this commit is actually
named slightly differently.

  file entry name: drivers/platform/surface/surface_aggregator_tablet_switch.c
  added file name: drivers/platform/surface/surface_aggregator_tabletsw.c

Hence, ./scripts/get_maintainer.pl --self-test=patterns complains about a
broken reference.

Repair this file entry to the actual file name added with the commit above.

Fixes: 9f794056db5b ("platform/surface: Add KIP/POS tablet-mode switch driver")
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220713040916.1767-1-lukas.bulwahn@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 MAINTAINERS | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/MAINTAINERS b/MAINTAINERS
index 55e80354a097..6772c9d0eccc 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -13303,7 +13303,7 @@ MICROSOFT SURFACE AGGREGATOR TABLET-MODE SWITCH
 M:	Maximilian Luz <luzmaximilian@gmail.com>
 L:	platform-driver-x86@vger.kernel.org
 S:	Maintained
-F:	drivers/platform/surface/surface_aggregator_tablet_switch.c
+F:	drivers/platform/surface/surface_aggregator_tabletsw.c
 
 MICROSOFT SURFACE BATTERY AND AC DRIVERS
 M:	Maximilian Luz <luzmaximilian@gmail.com>
-- 
2.38.0

From 5186ef74d3d66701d614de93666a74ca282b7f63 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Sun, 17 Jul 2022 14:07:35 +0200
Subject: [PATCH] platform/surface: tabletsw: Fix __le32 integer access

The sources.count field is a __le32 inside a packed struct. So use the
proper functions to access it.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 9f794056db5b ("platform/surface: Add KIP/POS tablet-mode switch driver")
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20220717120735.2052160-1-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Patchset: surface-sam
---
 drivers/platform/surface/surface_aggregator_tabletsw.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/surface/surface_aggregator_tabletsw.c b/drivers/platform/surface/surface_aggregator_tabletsw.c
index 596ca6c80681..27d95a6a7851 100644
--- a/drivers/platform/surface/surface_aggregator_tabletsw.c
+++ b/drivers/platform/surface/surface_aggregator_tabletsw.c
@@ -410,7 +410,7 @@ static int ssam_pos_get_source(struct ssam_tablet_sw *sw, u32 *source_id)
 	if (status)
 		return status;
 
-	if (sources.count == 0) {
+	if (get_unaligned_le32(&sources.count) == 0) {
 		dev_err(&sw->sdev->dev, "no posture sources found\n");
 		return -ENODEV;
 	}
@@ -422,7 +422,7 @@ static int ssam_pos_get_source(struct ssam_tablet_sw *sw, u32 *source_id)
 	 * is a device that provides multiple sources, at which point we can
 	 * then try to figure out how to handle them.
 	 */
-	WARN_ON(sources.count > 1);
+	WARN_ON(get_unaligned_le32(&sources.count) > 1);
 
 	*source_id = get_unaligned_le32(&sources.id[0]);
 	return 0;
-- 
2.38.0

From 8d9c314269418930276f16add5c811760cb5bceb Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Sat, 25 Jun 2022 20:42:00 +0200
Subject: [PATCH] platform/surface: aggregator_registry: Rename HID device
 nodes based on their function

Rename HID device nodes based on their function. In particular, these
are nodes for firmware updates via the CFU mechanism (component firmware
update), HID based sensors, and a USB-C UCSI client.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Patchset: surface-sam
---
 .../surface/surface_aggregator_registry.c      | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 93ab62eb393d..7d82398f55b1 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -104,14 +104,14 @@ static const struct software_node ssam_node_hid_tid1_touchpad = {
 	.parent = &ssam_node_root,
 };
 
-/* HID device instance 6 (TID1, unknown HID device). */
-static const struct software_node ssam_node_hid_tid1_iid6 = {
+/* HID device instance 6 (TID1, HID sensor collection). */
+static const struct software_node ssam_node_hid_tid1_sensors = {
 	.name = "ssam:01:15:01:06:00",
 	.parent = &ssam_node_root,
 };
 
-/* HID device instance 7 (TID1, unknown HID device). */
-static const struct software_node ssam_node_hid_tid1_iid7 = {
+/* HID device instance 7 (TID1, UCM UCSI HID client). */
+static const struct software_node ssam_node_hid_tid1_ucm_ucsi = {
 	.name = "ssam:01:15:01:07:00",
 	.parent = &ssam_node_root,
 };
@@ -182,8 +182,8 @@ static const struct software_node ssam_node_hid_kip_touchpad = {
 	.parent = &ssam_node_hub_kip,
 };
 
-/* HID device instance 5 (KIP hub, unknown HID device). */
-static const struct software_node ssam_node_hid_kip_iid5 = {
+/* HID device instance 5 (KIP hub, type-cover firmware update). */
+static const struct software_node ssam_node_hid_kip_fwupd = {
 	.name = "ssam:01:15:02:05:00",
 	.parent = &ssam_node_hub_kip,
 };
@@ -244,8 +244,8 @@ static const struct software_node *ssam_node_group_sls[] = {
 	&ssam_node_hid_tid1_keyboard,
 	&ssam_node_hid_tid1_penstash,
 	&ssam_node_hid_tid1_touchpad,
-	&ssam_node_hid_tid1_iid6,
-	&ssam_node_hid_tid1_iid7,
+	&ssam_node_hid_tid1_sensors,
+	&ssam_node_hid_tid1_ucm_ucsi,
 	&ssam_node_hid_tid1_sysctrl,
 	NULL,
 };
@@ -278,7 +278,7 @@ static const struct software_node *ssam_node_group_sp8[] = {
 	&ssam_node_hid_kip_keyboard,
 	&ssam_node_hid_kip_penstash,
 	&ssam_node_hid_kip_touchpad,
-	&ssam_node_hid_kip_iid5,
+	&ssam_node_hid_kip_fwupd,
 	NULL,
 };
 
-- 
2.38.0

From 60c2cdb4214c855aa92b1e23f15856eefbaef80f Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Sat, 25 Jun 2022 20:52:47 +0200
Subject: [PATCH] platform/surface: aggregator_registry: Rename HID device
 nodes based on new findings

On Windows, the HID devices with target ID 1 are grouped as "Surface Hot
Plug - SAM". Rename their device nodes in the registry to reflect that
and update the comments accordingly.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Patchset: surface-sam
---
 .../surface/surface_aggregator_registry.c     | 36 +++++++++----------
 1 file changed, 18 insertions(+), 18 deletions(-)

diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 7d82398f55b1..9970f89b1411 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -86,38 +86,38 @@ static const struct software_node ssam_node_bas_dtx = {
 	.parent = &ssam_node_root,
 };
 
-/* HID keyboard (TID1). */
-static const struct software_node ssam_node_hid_tid1_keyboard = {
+/* HID keyboard (SAM, TID=1). */
+static const struct software_node ssam_node_hid_sam_keyboard = {
 	.name = "ssam:01:15:01:01:00",
 	.parent = &ssam_node_root,
 };
 
-/* HID pen stash (TID1; pen taken / stashed away evens). */
-static const struct software_node ssam_node_hid_tid1_penstash = {
+/* HID pen stash (SAM, TID=1; pen taken / stashed away evens). */
+static const struct software_node ssam_node_hid_sam_penstash = {
 	.name = "ssam:01:15:01:02:00",
 	.parent = &ssam_node_root,
 };
 
-/* HID touchpad (TID1). */
-static const struct software_node ssam_node_hid_tid1_touchpad = {
+/* HID touchpad (SAM, TID=1). */
+static const struct software_node ssam_node_hid_sam_touchpad = {
 	.name = "ssam:01:15:01:03:00",
 	.parent = &ssam_node_root,
 };
 
-/* HID device instance 6 (TID1, HID sensor collection). */
-static const struct software_node ssam_node_hid_tid1_sensors = {
+/* HID device instance 6 (SAM, TID=1, HID sensor collection). */
+static const struct software_node ssam_node_hid_sam_sensors = {
 	.name = "ssam:01:15:01:06:00",
 	.parent = &ssam_node_root,
 };
 
-/* HID device instance 7 (TID1, UCM UCSI HID client). */
-static const struct software_node ssam_node_hid_tid1_ucm_ucsi = {
+/* HID device instance 7 (SAM, TID=1, UCM UCSI HID client). */
+static const struct software_node ssam_node_hid_sam_ucm_ucsi = {
 	.name = "ssam:01:15:01:07:00",
 	.parent = &ssam_node_root,
 };
 
-/* HID system controls (TID1). */
-static const struct software_node ssam_node_hid_tid1_sysctrl = {
+/* HID system controls (SAM, TID=1). */
+static const struct software_node ssam_node_hid_sam_sysctrl = {
 	.name = "ssam:01:15:01:08:00",
 	.parent = &ssam_node_root,
 };
@@ -241,12 +241,12 @@ static const struct software_node *ssam_node_group_sls[] = {
 	&ssam_node_bat_main,
 	&ssam_node_tmp_pprof,
 	&ssam_node_pos_tablet_switch,
-	&ssam_node_hid_tid1_keyboard,
-	&ssam_node_hid_tid1_penstash,
-	&ssam_node_hid_tid1_touchpad,
-	&ssam_node_hid_tid1_sensors,
-	&ssam_node_hid_tid1_ucm_ucsi,
-	&ssam_node_hid_tid1_sysctrl,
+	&ssam_node_hid_sam_keyboard,
+	&ssam_node_hid_sam_penstash,
+	&ssam_node_hid_sam_touchpad,
+	&ssam_node_hid_sam_sensors,
+	&ssam_node_hid_sam_ucm_ucsi,
+	&ssam_node_hid_sam_sysctrl,
 	NULL,
 };
 
-- 
2.38.0

From dbd435c49913b4e6f186647301f311fb1ab1e61c Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Sat, 25 Jun 2022 20:54:59 +0200
Subject: [PATCH] platform/surface: aggregator_registry: Add HID devices for
 sensors and UCSI client to SP8

Add software nodes for the HID sensor collection and the UCM UCSI HID
client to the Surface Pro 8. In contrast to the type-cover devices,
these devices are directly attached to the SAM controller, without any
hub.

This enables support for HID-based sensors, including the ones used for
automatic screen rotation, on the Surface Pro 8.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Patchset: surface-sam
---
 drivers/platform/surface/surface_aggregator_registry.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/platform/surface/surface_aggregator_registry.c b/drivers/platform/surface/surface_aggregator_registry.c
index 9970f89b1411..585911020cea 100644
--- a/drivers/platform/surface/surface_aggregator_registry.c
+++ b/drivers/platform/surface/surface_aggregator_registry.c
@@ -279,6 +279,8 @@ static const struct software_node *ssam_node_group_sp8[] = {
 	&ssam_node_hid_kip_penstash,
 	&ssam_node_hid_kip_touchpad,
 	&ssam_node_hid_kip_fwupd,
+	&ssam_node_hid_sam_sensors,
+	&ssam_node_hid_sam_ucm_ucsi,
 	NULL,
 };
 
-- 
2.38.0