linux-surface/patches/4.19/0011-surface-hotplug.patch

From 66b504d8006984efb0bf1e5537366239dadec10c Mon Sep 17 00:00:00 2001
From: Lukas Wunner <lukas@wunner.de>
Date: Tue, 31 Jul 2018 07:50:37 +0200
Subject: [PATCH] PCI: pciehp: Differentiate between surprise and safe removal

When removing PCI devices below a hotplug bridge, pciehp marks them as
disconnected if the card is no longer present in the slot or it quiesces
them if the card is still present (by disabling INTx interrupts, bus
mastering and SERR# reporting).

To detect whether the card is still present, pciehp checks the Presence
Detect State bit in the Slot Status register.  The problem with this
approach is that even if the card is present, the link to it may be
down, and it that case it would be better to mark the devices as
disconnected instead of trying to quiesce them.  Moreover, if the card
in the slot was quickly replaced by another one, the Presence Detect
State bit would be set, yet trying to quiesce the new card's devices
would be wrong and the correct thing to do is to mark the previous
card's devices as disconnected.

Instead of looking at the Presence Detect State bit, it is better to
differentiate whether the card was surprise removed versus safely
removed (via sysfs or an Attention Button press).  On surprise removal,
the devices should be marked as disconnected, whereas on safe removal it
is correct to quiesce the devices.

The knowledge whether a surprise removal or a safe removal is at hand
does exist further up in the call stack:  A surprise removal is
initiated by pciehp_handle_presence_or_link_change(), a safe removal by
pciehp_handle_disable_request().

Pass that information down to pciehp_unconfigure_device() and use it in
lieu of the Presence Detect State bit.  While there, add kernel-doc to
pciehp_unconfigure_device() and pciehp_configure_device().

Tested-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Keith Busch <keith.busch@intel.com>

Patchset: surface-hotplug
---
 drivers/pci/hotplug/pciehp.h      |  2 +-
 drivers/pci/hotplug/pciehp_ctrl.c | 22 +++++++++++++---------
 drivers/pci/hotplug/pciehp_pci.c  | 23 ++++++++++++++++++++---
 3 files changed, 34 insertions(+), 13 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index ef6071807072..13379bc6a466 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -183,7 +183,7 @@ void pciehp_handle_button_press(struct slot *slot);
 void pciehp_handle_disable_request(struct slot *slot);
 void pciehp_handle_presence_or_link_change(struct slot *slot, u32 events);
 int pciehp_configure_device(struct slot *p_slot);
-void pciehp_unconfigure_device(struct slot *p_slot);
+void pciehp_unconfigure_device(struct slot *p_slot, bool presence);
 void pciehp_queue_pushbutton_work(struct work_struct *work);
 struct controller *pcie_init(struct pcie_device *dev);
 int pcie_init_notification(struct controller *ctrl);
diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c
index c71964e29b01..60a925066b0a 100644
--- a/drivers/pci/hotplug/pciehp_ctrl.c
+++ b/drivers/pci/hotplug/pciehp_ctrl.c
@@ -26,6 +26,9 @@
    hotplug controller logic
  */
 
+#define SAFE_REMOVAL	 true
+#define SURPRISE_REMOVAL false
+
 static void set_slot_off(struct controller *ctrl, struct slot *pslot)
 {
 	/* turn off slot, turn on Amber LED, turn off Green LED if supported*/
@@ -101,12 +104,13 @@ static int board_added(struct slot *p_slot)
 /**
  * remove_board - Turns off slot and LEDs
  * @p_slot: slot where board is being removed
+ * @safe_removal: whether the board is safely removed (versus surprise removed)
  */
-static void remove_board(struct slot *p_slot)
+static void remove_board(struct slot *p_slot, bool safe_removal)
 {
 	struct controller *ctrl = p_slot->ctrl;
 
-	pciehp_unconfigure_device(p_slot);
+	pciehp_unconfigure_device(p_slot, safe_removal);
 
 	if (POWER_CTRL(ctrl)) {
 		pciehp_power_off_slot(p_slot);
@@ -128,7 +132,7 @@ static void remove_board(struct slot *p_slot)
 }
 
 static int pciehp_enable_slot(struct slot *slot);
-static int pciehp_disable_slot(struct slot *slot);
+static int pciehp_disable_slot(struct slot *slot, bool safe_removal);
 
 void pciehp_request(struct controller *ctrl, int action)
 {
@@ -220,7 +224,7 @@ void pciehp_handle_disable_request(struct slot *slot)
 	slot->state = POWEROFF_STATE;
 	mutex_unlock(&slot->lock);
 
-	ctrl->request_result = pciehp_disable_slot(slot);
+	ctrl->request_result = pciehp_disable_slot(slot, SAFE_REMOVAL);
 }
 
 void pciehp_handle_presence_or_link_change(struct slot *slot, u32 events)
@@ -247,7 +251,7 @@ void pciehp_handle_presence_or_link_change(struct slot *slot, u32 events)
 		if (events & PCI_EXP_SLTSTA_PDC)
 			ctrl_info(ctrl, "Slot(%s): Card not present\n",
 				  slot_name(slot));
-		pciehp_disable_slot(slot);
+		pciehp_disable_slot(slot, SURPRISE_REMOVAL);
 		break;
 	default:
 		mutex_unlock(&slot->lock);
@@ -333,7 +337,7 @@ static int pciehp_enable_slot(struct slot *slot)
 	return ret;
 }
 
-static int __pciehp_disable_slot(struct slot *p_slot)
+static int __pciehp_disable_slot(struct slot *p_slot, bool safe_removal)
 {
 	u8 getstatus = 0;
 	struct controller *ctrl = p_slot->ctrl;
@@ -347,17 +351,17 @@ static int __pciehp_disable_slot(struct slot *p_slot)
 		}
 	}
 
-	remove_board(p_slot);
+	remove_board(p_slot, safe_removal);
 	return 0;
 }
 
-static int pciehp_disable_slot(struct slot *slot)
+static int pciehp_disable_slot(struct slot *slot, bool safe_removal)
 {
 	struct controller *ctrl = slot->ctrl;
 	int ret;
 
 	pm_runtime_get_sync(&ctrl->pcie->port->dev);
-	ret = __pciehp_disable_slot(slot);
+	ret = __pciehp_disable_slot(slot, safe_removal);
 	pm_runtime_put(&ctrl->pcie->port->dev);
 
 	mutex_lock(&slot->lock);
diff --git a/drivers/pci/hotplug/pciehp_pci.c b/drivers/pci/hotplug/pciehp_pci.c
index 5c58c22e0c08..18f83e554c73 100644
--- a/drivers/pci/hotplug/pciehp_pci.c
+++ b/drivers/pci/hotplug/pciehp_pci.c
@@ -20,6 +20,14 @@
 #include "../pci.h"
 #include "pciehp.h"
 
+/**
+ * pciehp_configure_device() - enumerate PCI devices below a hotplug bridge
+ * @p_slot: PCIe hotplug slot
+ *
+ * Enumerate PCI devices below a hotplug bridge and add them to the system.
+ * Return 0 on success, %-EEXIST if the devices are already enumerated or
+ * %-ENODEV if enumeration failed.
+ */
 int pciehp_configure_device(struct slot *p_slot)
 {
 	struct pci_dev *dev;
@@ -62,9 +70,19 @@ int pciehp_configure_device(struct slot *p_slot)
 	return ret;
 }
 
-void pciehp_unconfigure_device(struct slot *p_slot)
+/**
+ * pciehp_unconfigure_device() - remove PCI devices below a hotplug bridge
+ * @p_slot: PCIe hotplug slot
+ * @presence: whether the card is still present in the slot;
+ *	true for safe removal via sysfs or an Attention Button press,
+ *	false for surprise removal
+ *
+ * Unbind PCI devices below a hotplug bridge from their drivers and remove
+ * them from the system.  Safely removed devices are quiesced.  Surprise
+ * removed devices are marked as such to prevent further accesses.
+ */
+void pciehp_unconfigure_device(struct slot *p_slot, bool presence)
 {
-	u8 presence = 0;
 	struct pci_dev *dev, *temp;
 	struct pci_bus *parent = p_slot->ctrl->pcie->port->subordinate;
 	u16 command;
@@ -72,7 +90,6 @@ void pciehp_unconfigure_device(struct slot *p_slot)
 
 	ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:00\n",
 		 __func__, pci_domain_nr(parent), parent->number);
-	pciehp_get_adapter_status(p_slot, &presence);
 
 	pci_lock_rescan_remove();
 
-- 
2.33.0

From 3b713ee79a44cf32d640b89a815a87c66ad12b64 Mon Sep 17 00:00:00 2001
From: Lukas Wunner <lukas@wunner.de>
Date: Sun, 19 Aug 2018 16:29:00 +0200
Subject: [PATCH] PCI: pciehp: Drop unnecessary includes

Drop the following includes from pciehp source files which no longer use
any of the included symbols:

* <linux/sched/signal.h> in pciehp.h
  <linux/signal.h> in pciehp_hpc.c
  Added by commit de25968cc87c ("fix more missing includes") to
  accommodate for a call to signal_pending().
  The call was removed by commit 262303fe329a ("pciehp: fix wait command
  completion").

* <linux/interrupt.h> in pciehp_core.c
  Added by historic commit f308a2dfbe63 ("PCI: add PCI Express Port Bus
  Driver subsystem") to accommodate for a call to free_irq():
  https://git.kernel.org/tglx/history/c/f308a2dfbe63
  The call was removed by commit 407f452b05f9 ("pciehp: remove
  unnecessary free_irq").

* <linux/time.h> in pciehp_core.c and pciehp_hpc.c
  Added by commit 34d03419f03b ("PCIEHP: Add Electro Mechanical
  Interlock (EMI) support to the PCIE hotplug driver."),
  which was reverted by commit bd3d99c17039 ("PCI: Remove untested
  Electromechanical Interlock (EMI) support in pciehp.").

* <linux/module.h> in pciehp_ctrl.c, pciehp_hpc.c and pciehp_pci.c
  Added by historic commit c16b4b14d980 ("PCI Hotplug: Add SHPC and PCI
  Express hot-plug drivers"):
  https://git.kernel.org/tglx/history/c/c16b4b14d980
  Module-related symbols were neither used back then in those files,
  nor are they used today.

* <linux/slab.h> in pciehp_ctrl.c
  Added by commit 5a0e3ad6af86 ("include cleanup: Update gfp.h and
  slab.h includes to prepare for breaking implicit slab.h inclusion from
  percpu.h") to accommodate for calls to kmalloc().
  The calls were removed by commit 0e94916e6091 ("PCI: pciehp: Handle
  events synchronously").

* "../pci.h" in pciehp_ctrl.c
  Added by historic commit 67f4660b72f2 ("PCI: ASPM patch for") to
  accommodate for usage of the global variable pcie_mch_quirk:
  https://git.kernel.org/tglx/history/c/67f4660b72f2
  The global variable was removed by commit 0ba379ec0fb1 ("PCI: Simplify
  hotplug mch quirk").

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Patchset: surface-hotplug
---
 drivers/pci/hotplug/pciehp.h      | 1 -
 drivers/pci/hotplug/pciehp_core.c | 2 --
 drivers/pci/hotplug/pciehp_ctrl.c | 3 ---
 drivers/pci/hotplug/pciehp_hpc.c  | 3 ---
 drivers/pci/hotplug/pciehp_pci.c  | 1 -
 5 files changed, 10 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 13379bc6a466..48d138c59f5d 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -19,7 +19,6 @@
 #include <linux/pci.h>
 #include <linux/pci_hotplug.h>
 #include <linux/delay.h>
-#include <linux/sched/signal.h>		/* signal_pending() */
 #include <linux/mutex.h>
 #include <linux/rwsem.h>
 #include <linux/workqueue.h>
diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index 518c46f8e63b..8e5b0bdb16b6 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -23,8 +23,6 @@
 #include <linux/types.h>
 #include <linux/pci.h>
 #include "pciehp.h"
-#include <linux/interrupt.h>
-#include <linux/time.h>
 
 #include "../pci.h"
 
diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c
index 60a925066b0a..10e46e3cdcea 100644
--- a/drivers/pci/hotplug/pciehp_ctrl.c
+++ b/drivers/pci/hotplug/pciehp_ctrl.c
@@ -13,13 +13,10 @@
  *
  */
 
-#include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/types.h>
-#include <linux/slab.h>
 #include <linux/pm_runtime.h>
 #include <linux/pci.h>
-#include "../pci.h"
 #include "pciehp.h"
 
 /* The following routines constitute the bulk of the
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 005817e40ad3..d4b7049cbc70 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -13,15 +13,12 @@
  */
 
 #include <linux/kernel.h>
-#include <linux/module.h>
 #include <linux/types.h>
-#include <linux/signal.h>
 #include <linux/jiffies.h>
 #include <linux/kthread.h>
 #include <linux/pci.h>
 #include <linux/pm_runtime.h>
 #include <linux/interrupt.h>
-#include <linux/time.h>
 #include <linux/slab.h>
 
 #include "../pci.h"
diff --git a/drivers/pci/hotplug/pciehp_pci.c b/drivers/pci/hotplug/pciehp_pci.c
index 18f83e554c73..c512b2ed85ed 100644
--- a/drivers/pci/hotplug/pciehp_pci.c
+++ b/drivers/pci/hotplug/pciehp_pci.c
@@ -13,7 +13,6 @@
  *
  */
 
-#include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/pci.h>
-- 
2.33.0

From 750b78bfc3145422f62dae68f35834c59aa553fe Mon Sep 17 00:00:00 2001
From: Lukas Wunner <lukas@wunner.de>
Date: Sun, 19 Aug 2018 16:29:00 +0200
Subject: [PATCH] PCI: pciehp: Drop hotplug_slot_ops wrappers

pciehp's ->enable_slot, ->disable_slot, ->get_attention_status and
->reset_slot callbacks are currently implemented by wrapper functions
that do nothing else but call down to a backend function.  The backends
are not called from anywhere else, so drop the wrappers and use the
backends directly as callbacks, thereby shaving off a few lines of
unnecessary code.

No functional change intended.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Patchset: surface-hotplug
---
 drivers/pci/hotplug/pciehp.h      |  8 +++---
 drivers/pci/hotplug/pciehp_core.c | 43 +++----------------------------
 drivers/pci/hotplug/pciehp_ctrl.c |  6 +++--
 drivers/pci/hotplug/pciehp_hpc.c  |  8 ++++--
 4 files changed, 18 insertions(+), 47 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 48d138c59f5d..79feeb0a6716 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -175,8 +175,6 @@ struct controller {
 #define NO_CMD_CMPL(ctrl)	((ctrl)->slot_cap & PCI_EXP_SLTCAP_NCCS)
 #define PSN(ctrl)		(((ctrl)->slot_cap & PCI_EXP_SLTCAP_PSN) >> 19)
 
-int pciehp_sysfs_enable_slot(struct slot *slot);
-int pciehp_sysfs_disable_slot(struct slot *slot);
 void pciehp_request(struct controller *ctrl, int action);
 void pciehp_handle_button_press(struct slot *slot);
 void pciehp_handle_disable_request(struct slot *slot);
@@ -191,7 +189,6 @@ void pcie_clear_hotplug_events(struct controller *ctrl);
 int pciehp_power_on_slot(struct slot *slot);
 void pciehp_power_off_slot(struct slot *slot);
 void pciehp_get_power_status(struct slot *slot, u8 *status);
-void pciehp_get_attention_status(struct slot *slot, u8 *status);
 
 void pciehp_set_attention_status(struct slot *slot, u8 status);
 void pciehp_get_latch_status(struct slot *slot, u8 *status);
@@ -203,8 +200,11 @@ void pciehp_green_led_blink(struct slot *slot);
 int pciehp_check_link_status(struct controller *ctrl);
 bool pciehp_check_link_active(struct controller *ctrl);
 void pciehp_release_ctrl(struct controller *ctrl);
-int pciehp_reset_slot(struct slot *slot, int probe);
 
+int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot);
+int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot);
+int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, int probe);
+int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status);
 int pciehp_set_raw_indicator_status(struct hotplug_slot *h_slot, u8 status);
 int pciehp_get_raw_indicator_status(struct hotplug_slot *h_slot, u8 *status);
 
diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index 8e5b0bdb16b6..c796c4643bbc 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -45,13 +45,9 @@ MODULE_PARM_DESC(pciehp_poll_time, "Polling mechanism frequency, in seconds");
 #define PCIE_MODULE_NAME "pciehp"
 
 static int set_attention_status(struct hotplug_slot *slot, u8 value);
-static int enable_slot(struct hotplug_slot *slot);
-static int disable_slot(struct hotplug_slot *slot);
 static int get_power_status(struct hotplug_slot *slot, u8 *value);
-static int get_attention_status(struct hotplug_slot *slot, u8 *value);
 static int get_latch_status(struct hotplug_slot *slot, u8 *value);
 static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
-static int reset_slot(struct hotplug_slot *slot, int probe);
 
 static int init_slot(struct controller *ctrl)
 {
@@ -75,15 +71,15 @@ static int init_slot(struct controller *ctrl)
 	if (!ops)
 		goto out;
 
-	ops->enable_slot = enable_slot;
-	ops->disable_slot = disable_slot;
+	ops->enable_slot = pciehp_sysfs_enable_slot;
+	ops->disable_slot = pciehp_sysfs_disable_slot;
 	ops->get_power_status = get_power_status;
 	ops->get_adapter_status = get_adapter_status;
-	ops->reset_slot = reset_slot;
+	ops->reset_slot = pciehp_reset_slot;
 	if (MRL_SENS(ctrl))
 		ops->get_latch_status = get_latch_status;
 	if (ATTN_LED(ctrl)) {
-		ops->get_attention_status = get_attention_status;
+		ops->get_attention_status = pciehp_get_attention_status;
 		ops->set_attention_status = set_attention_status;
 	} else if (ctrl->pcie->port->hotplug_user_indicators) {
 		ops->get_attention_status = pciehp_get_raw_indicator_status;
@@ -134,22 +130,6 @@ static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
 	return 0;
 }
 
-
-static int enable_slot(struct hotplug_slot *hotplug_slot)
-{
-	struct slot *slot = hotplug_slot->private;
-
-	return pciehp_sysfs_enable_slot(slot);
-}
-
-
-static int disable_slot(struct hotplug_slot *hotplug_slot)
-{
-	struct slot *slot = hotplug_slot->private;
-
-	return pciehp_sysfs_disable_slot(slot);
-}
-
 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
 {
 	struct slot *slot = hotplug_slot->private;
@@ -161,14 +141,6 @@ static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
 	return 0;
 }
 
-static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
-{
-	struct slot *slot = hotplug_slot->private;
-
-	pciehp_get_attention_status(slot, value);
-	return 0;
-}
-
 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
 {
 	struct slot *slot = hotplug_slot->private;
@@ -191,13 +163,6 @@ static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
 	return 0;
 }
 
-static int reset_slot(struct hotplug_slot *hotplug_slot, int probe)
-{
-	struct slot *slot = hotplug_slot->private;
-
-	return pciehp_reset_slot(slot, probe);
-}
-
 /**
  * pciehp_check_presence() - synthesize event if presence has changed
  *
diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c
index 10e46e3cdcea..b101f179147e 100644
--- a/drivers/pci/hotplug/pciehp_ctrl.c
+++ b/drivers/pci/hotplug/pciehp_ctrl.c
@@ -368,8 +368,9 @@ static int pciehp_disable_slot(struct slot *slot, bool safe_removal)
 	return ret;
 }
 
-int pciehp_sysfs_enable_slot(struct slot *p_slot)
+int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot)
 {
+	struct slot *p_slot = hotplug_slot->private;
 	struct controller *ctrl = p_slot->ctrl;
 
 	mutex_lock(&p_slot->lock);
@@ -407,8 +408,9 @@ int pciehp_sysfs_enable_slot(struct slot *p_slot)
 	return -ENODEV;
 }
 
-int pciehp_sysfs_disable_slot(struct slot *p_slot)
+int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot)
 {
+	struct slot *p_slot = hotplug_slot->private;
 	struct controller *ctrl = p_slot->ctrl;
 
 	mutex_lock(&p_slot->lock);
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index d4b7049cbc70..576362d0b1cd 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -326,8 +326,9 @@ int pciehp_get_raw_indicator_status(struct hotplug_slot *hotplug_slot,
 	return 0;
 }
 
-void pciehp_get_attention_status(struct slot *slot, u8 *status)
+int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status)
 {
+	struct slot *slot = hotplug_slot->private;
 	struct controller *ctrl = slot->ctrl;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 slot_ctrl;
@@ -352,6 +353,8 @@ void pciehp_get_attention_status(struct slot *slot, u8 *status)
 		*status = 0xFF;
 		break;
 	}
+
+	return 0;
 }
 
 void pciehp_get_power_status(struct slot *slot, u8 *status)
@@ -769,8 +772,9 @@ void pcie_clear_hotplug_events(struct controller *ctrl)
  * momentarily, if we see that they could interfere. Also, clear any spurious
  * events after.
  */
-int pciehp_reset_slot(struct slot *slot, int probe)
+int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, int probe)
 {
+	struct slot *slot = hotplug_slot->private;
 	struct controller *ctrl = slot->ctrl;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 stat_mask = 0, ctrl_mask = 0;
-- 
2.33.0

From 01519bdc9263ba3ee3c2ddf2866e07f39cd345e3 Mon Sep 17 00:00:00 2001
From: Lukas Wunner <lukas@wunner.de>
Date: Sat, 8 Sep 2018 09:59:01 +0200
Subject: [PATCH] PCI: pciehp: Tolerate Presence Detect hardwired to zero

The WiGig Bus Extension (WBE) specification allows tunneling PCIe over
IEEE 802.11.  A product implementing this spec is the wil6210 from
Wilocity (now part of Qualcomm Atheros).  It integrates a PCIe switch
with a wireless network adapter:

  00.0-+              [1ae9:0101]  Upstream Port
       +-00.0-+       [1ae9:0200]  Downstream Port
       |      +-00.0  [168c:0034]  Atheros AR9462 Wireless Network Adapter
       +-02.0         [1ae9:0201]  Downstream Port
       +-03.0         [1ae9:0201]  Downstream Port

Wirelessly attached devices presumably appear below the hotplug ports
with device ID [1ae9:0201].  Oddly, the Downstream Port [1ae9:0200]
leading to the wireless network adapter is likewise Hotplug Capable,
but has its Presence Detect State bit hardwired to zero.  Even if the
Link Active bit is set, Presence Detect is zero, so this cannot be
caused by in-band presence detection but only by broken hardware.

pciehp assumes an empty slot if Presence Detect State is zero,
regardless of Link Active being one.  Consequently, up until v4.18 it
removes the wireless network adapter in pciehp_resume().  From v4.19 it
already does so in pciehp_probe().

Be lenient towards broken hardware and assume the slot is occupied if
Link Active is set:  Introduce pciehp_card_present_or_link_active()
and use it in lieu of pciehp_get_adapter_status() everywhere, except
in pciehp_handle_presence_or_link_change() whose log messages depend
on which of Presence Detect State or Link Active is set.

Remove the Presence Detect State check from __pciehp_enable_slot()
because it is only called if either of Presence Detect State or Link
Active is set.

Caution: There is a possibility that broken hardware exists which has
working Presence Detect but hardwires Link Active to one.  On such
hardware the slot will now incorrectly be considered always occupied.
If such hardware is discovered, this commit can be rolled back and a
quirk can be added which sets is_hotplug_bridge = 0 for [1ae9:0200].

Link: https://bugzilla.kernel.org/show_bug.cgi?id=200839
Reported-and-tested-by: David Yang <mmyangfl@gmail.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Rajat Jain <rajatja@google.com>
Cc: Ashok Raj <ashok.raj@intel.com>

Patchset: surface-hotplug
---
 drivers/pci/hotplug/pciehp.h      |  3 ++-
 drivers/pci/hotplug/pciehp_core.c |  6 +++---
 drivers/pci/hotplug/pciehp_ctrl.c | 10 ++--------
 drivers/pci/hotplug/pciehp_hpc.c  | 25 +++++++++++++++++++------
 4 files changed, 26 insertions(+), 18 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 79feeb0a6716..d1fa2ce71ad9 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -192,11 +192,12 @@ void pciehp_get_power_status(struct slot *slot, u8 *status);
 
 void pciehp_set_attention_status(struct slot *slot, u8 status);
 void pciehp_get_latch_status(struct slot *slot, u8 *status);
-void pciehp_get_adapter_status(struct slot *slot, u8 *status);
 int pciehp_query_power_fault(struct slot *slot);
 void pciehp_green_led_on(struct slot *slot);
 void pciehp_green_led_off(struct slot *slot);
 void pciehp_green_led_blink(struct slot *slot);
+bool pciehp_card_present(struct controller *ctrl);
+bool pciehp_card_present_or_link_active(struct controller *ctrl);
 int pciehp_check_link_status(struct controller *ctrl);
 bool pciehp_check_link_active(struct controller *ctrl);
 void pciehp_release_ctrl(struct controller *ctrl);
diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index c796c4643bbc..c052efe421f3 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -158,7 +158,7 @@ static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
 	struct pci_dev *pdev = slot->ctrl->pcie->port;
 
 	pci_config_pm_runtime_get(pdev);
-	pciehp_get_adapter_status(slot, value);
+	*value = pciehp_card_present_or_link_active(slot->ctrl);
 	pci_config_pm_runtime_put(pdev);
 	return 0;
 }
@@ -176,12 +176,12 @@ static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
 static void pciehp_check_presence(struct controller *ctrl)
 {
 	struct slot *slot = ctrl->slot;
-	u8 occupied;
+	bool occupied;
 
 	down_read(&ctrl->reset_lock);
 	mutex_lock(&slot->lock);
 
-	pciehp_get_adapter_status(slot, &occupied);
+	occupied = pciehp_card_present_or_link_active(ctrl);
 	if ((occupied && (slot->state == OFF_STATE ||
 			  slot->state == BLINKINGON_STATE)) ||
 	    (!occupied && (slot->state == ON_STATE ||
diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c
index b101f179147e..97fa865717ec 100644
--- a/drivers/pci/hotplug/pciehp_ctrl.c
+++ b/drivers/pci/hotplug/pciehp_ctrl.c
@@ -227,8 +227,7 @@ void pciehp_handle_disable_request(struct slot *slot)
 void pciehp_handle_presence_or_link_change(struct slot *slot, u32 events)
 {
 	struct controller *ctrl = slot->ctrl;
-	bool link_active;
-	u8 present;
+	bool present, link_active;
 
 	/*
 	 * If the slot is on and presence or link has changed, turn it off.
@@ -257,7 +256,7 @@ void pciehp_handle_presence_or_link_change(struct slot *slot, u32 events)
 
 	/* Turn the slot on if it's occupied or link is up */
 	mutex_lock(&slot->lock);
-	pciehp_get_adapter_status(slot, &present);
+	present = pciehp_card_present(ctrl);
 	link_active = pciehp_check_link_active(ctrl);
 	if (!present && !link_active) {
 		mutex_unlock(&slot->lock);
@@ -290,11 +289,6 @@ static int __pciehp_enable_slot(struct slot *p_slot)
 	u8 getstatus = 0;
 	struct controller *ctrl = p_slot->ctrl;
 
-	pciehp_get_adapter_status(p_slot, &getstatus);
-	if (!getstatus) {
-		ctrl_info(ctrl, "Slot(%s): No adapter\n", slot_name(p_slot));
-		return -ENODEV;
-	}
 	if (MRL_SENS(p_slot->ctrl)) {
 		pciehp_get_latch_status(p_slot, &getstatus);
 		if (getstatus) {
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 576362d0b1cd..7f4173d6771a 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -389,13 +389,27 @@ void pciehp_get_latch_status(struct slot *slot, u8 *status)
 	*status = !!(slot_status & PCI_EXP_SLTSTA_MRLSS);
 }
 
-void pciehp_get_adapter_status(struct slot *slot, u8 *status)
+bool pciehp_card_present(struct controller *ctrl)
 {
-	struct pci_dev *pdev = ctrl_dev(slot->ctrl);
+	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 slot_status;
 
 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
-	*status = !!(slot_status & PCI_EXP_SLTSTA_PDS);
+	return slot_status & PCI_EXP_SLTSTA_PDS;
+}
+
+/**
+ * pciehp_card_present_or_link_active() - whether given slot is occupied
+ * @ctrl: PCIe hotplug controller
+ *
+ * Unlike pciehp_card_present(), which determines presence solely from the
+ * Presence Detect State bit, this helper also returns true if the Link Active
+ * bit is set.  This is a concession to broken hotplug ports which hardwire
+ * Presence Detect State to zero, such as Wilocity's [1ae9:0200].
+ */
+bool pciehp_card_present_or_link_active(struct controller *ctrl)
+{
+	return pciehp_card_present(ctrl) || pciehp_check_link_active(ctrl);
 }
 
 int pciehp_query_power_fault(struct slot *slot)
@@ -874,7 +888,7 @@ struct controller *pcie_init(struct pcie_device *dev)
 {
 	struct controller *ctrl;
 	u32 slot_cap, link_cap;
-	u8 occupied, poweron;
+	u8 poweron;
 	struct pci_dev *pdev = dev->port;
 
 	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
@@ -934,9 +948,8 @@ struct controller *pcie_init(struct pcie_device *dev)
 	 * requested yet, so avoid triggering a notification with this command.
 	 */
 	if (POWER_CTRL(ctrl)) {
-		pciehp_get_adapter_status(ctrl->slot, &occupied);
 		pciehp_get_power_status(ctrl->slot, &poweron);
-		if (!occupied && poweron) {
+		if (!pciehp_card_present_or_link_active(ctrl) && poweron) {
 			pcie_disable_notification(ctrl);
 			pciehp_power_off_slot(ctrl->slot);
 		}
-- 
2.33.0

From 50a34b9ff91d80b612c35fad1f8dd50b845c7c7e Mon Sep 17 00:00:00 2001
From: Patrick Talbert <ptalbert@redhat.com>
Date: Wed, 5 Sep 2018 09:12:53 +0200
Subject: [PATCH] PCI/ASPM: Do not initialize link state when aspm_disabled is
 set

Now that ASPM is configured for *all* PCIe devices at boot, a problem is
seen with systems that set the FADT NO_ASPM bit.  This bit indicates that
the OS should not alter the ASPM state, but when
pcie_aspm_init_link_state() runs it only checks for !aspm_support_enabled.
This misses the ACPI_FADT_NO_ASPM case because that is setting
aspm_disabled.

The result is systems may hang at boot after 1302fcf; avoidable if they
boot with pcie_aspm=off (sets !aspm_support_enabled).

Fix this by having aspm_init_link_state() check for either
!aspm_support_enabled or acpm_disabled.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=201001
Fixes: 1302fcf0d03e ("PCI: Configure *all* devices, not just hot-added ones")
Signed-off-by: Patrick Talbert <ptalbert@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Patchset: surface-hotplug
---
 drivers/pci/pcie/aspm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index cb474338f39d..18aa830e79e4 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -907,7 +907,7 @@ void pcie_aspm_init_link_state(struct pci_dev *pdev)
 	struct pcie_link_state *link;
 	int blacklist = !!pcie_aspm_sanity_check(pdev);
 
-	if (!aspm_support_enabled)
+	if (!aspm_support_enabled || aspm_disabled)
 		return;
 
 	if (pdev->link_state)
-- 
2.33.0

From 8e7c633b192cda8a5d12be0edc6c5083e49b57d6 Mon Sep 17 00:00:00 2001
From: Lukas Wunner <lukas@wunner.de>
Date: Sun, 19 Aug 2018 16:29:00 +0200
Subject: [PATCH] PCI: Simplify disconnected marking

Commit 89ee9f768003 ("PCI: Add device disconnected state") iterates over
the devices on a parent bus, marks each as disconnected, then marks
each device's children as disconnected using pci_walk_bus().

The same can be achieved more succinctly by calling pci_walk_bus() on
the parent bus.  Moreover, this does not need to wait until acquiring
pci_lock_rescan_remove(), so move it out of that critical section.

The critical section in err.c contains a pci_dev_get() / pci_dev_put()
pair which was apparently copy-pasted from pciehp_pci.c.  In the latter
it serves the purpose of holding the struct pci_dev in place until the
Command register is updated.  err.c doesn't do anything like that, hence
the pair is unnecessary.  Remove it.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Oza Pawandeep <poza@codeaurora.org>
Cc: Sinan Kaya <okaya@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Patchset: surface-hotplug
---
 drivers/pci/hotplug/pciehp_pci.c | 9 +++------
 drivers/pci/pcie/err.c           | 8 ++------
 2 files changed, 5 insertions(+), 12 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp_pci.c b/drivers/pci/hotplug/pciehp_pci.c
index c512b2ed85ed..8da87931bd45 100644
--- a/drivers/pci/hotplug/pciehp_pci.c
+++ b/drivers/pci/hotplug/pciehp_pci.c
@@ -90,6 +90,9 @@ void pciehp_unconfigure_device(struct slot *p_slot, bool presence)
 	ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:00\n",
 		 __func__, pci_domain_nr(parent), parent->number);
 
+	if (!presence)
+		pci_walk_bus(parent, pci_dev_set_disconnected, NULL);
+
 	pci_lock_rescan_remove();
 
 	/*
@@ -101,12 +104,6 @@ void pciehp_unconfigure_device(struct slot *p_slot, bool presence)
 	list_for_each_entry_safe_reverse(dev, temp, &parent->devices,
 					 bus_list) {
 		pci_dev_get(dev);
-		if (!presence) {
-			pci_dev_set_disconnected(dev, NULL);
-			if (pci_has_subordinate(dev))
-				pci_walk_bus(dev->subordinate,
-					     pci_dev_set_disconnected, NULL);
-		}
 		pci_stop_and_remove_bus_device(dev);
 		/*
 		 * Ensure that no new Requests will be generated from
diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c
index 2c3b5bd59b18..dee5a7507403 100644
--- a/drivers/pci/pcie/err.c
+++ b/drivers/pci/pcie/err.c
@@ -239,17 +239,13 @@ void pcie_do_fatal_recovery(struct pci_dev *dev, u32 service)
 		udev = dev->bus->self;
 
 	parent = udev->subordinate;
+	pci_walk_bus(parent, pci_dev_set_disconnected, NULL);
+
 	pci_lock_rescan_remove();
 	pci_dev_get(dev);
 	list_for_each_entry_safe_reverse(pdev, temp, &parent->devices,
 					 bus_list) {
-		pci_dev_get(pdev);
-		pci_dev_set_disconnected(pdev, NULL);
-		if (pci_has_subordinate(pdev))
-			pci_walk_bus(pdev->subordinate,
-				     pci_dev_set_disconnected, NULL);
 		pci_stop_and_remove_bus_device(pdev);
-		pci_dev_put(pdev);
 	}
 
 	result = reset_link(udev, service);
-- 
2.33.0

From 4a7b80f9dcd4d105ff29f98071e19107d9bb2cec Mon Sep 17 00:00:00 2001
From: Lukas Wunner <lukas@wunner.de>
Date: Tue, 18 Sep 2018 21:46:17 +0200
Subject: [PATCH] PCI: pciehp: Unify controller and slot structs

pciehp was originally introduced together with shpchp in a single
commit, c16b4b14d980 ("PCI Hotplug: Add SHPC and PCI Express hot-plug
drivers"):
https://git.kernel.org/tglx/history/c/c16b4b14d980

shpchp supports up to 31 slots per controller, hence uses separate slot
and controller structs.  pciehp has a 1:1 relationship between slot and
controller and therefore never required this separation.  Nevertheless,
because much of the code had been copy-pasted between the two drivers,
pciehp likewise uses separate structs to this very day.

The artificial separation of data structures adds unnecessary complexity
and bloat to pciehp and requires constantly chasing pointers at runtime.

Simplify the driver by merging struct slot into struct controller.
Merge the slot constructor pcie_init_slot() and the destructor
pcie_cleanup_slot() into the controller counterparts.

No functional change intended.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Patchset: surface-hotplug
---
 drivers/pci/hotplug/pciehp.h      |  67 ++++----
 drivers/pci/hotplug/pciehp_core.c |  53 +++----
 drivers/pci/hotplug/pciehp_ctrl.c | 244 ++++++++++++++----------------
 drivers/pci/hotplug/pciehp_hpc.c  | 114 +++++---------
 drivers/pci/hotplug/pciehp_pci.c  |  14 +-
 5 files changed, 210 insertions(+), 282 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index d1fa2ce71ad9..bf1c9d3a64a5 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -58,24 +58,6 @@ do {									\
 
 #define SLOT_NAME_SIZE 10
 
-/**
- * struct slot - PCIe hotplug slot
- * @state: current state machine position
- * @ctrl: pointer to the slot's controller structure
- * @hotplug_slot: pointer to the structure registered with the PCI hotplug core
- * @work: work item to turn the slot on or off after 5 seconds in response to
- *	an Attention Button press
- * @lock: protects reads and writes of @state;
- *	protects scheduling, execution and cancellation of @work
- */
-struct slot {
-	u8 state;
-	struct controller *ctrl;
-	struct hotplug_slot *hotplug_slot;
-	struct delayed_work work;
-	struct mutex lock;
-};
-
 /**
  * struct controller - PCIe hotplug controller
  * @ctrl_lock: serializes writes to the Slot Control register
@@ -83,7 +65,6 @@ struct slot {
  * @reset_lock: prevents access to the Data Link Layer Link Active bit in the
  *	Link Status register and to the Presence Detect State bit in the Slot
  *	Status register during a slot reset which may cause them to flap
- * @slot: pointer to the controller's slot structure
  * @queue: wait queue to wake up on reception of a Command Completed event,
  *	used for synchronous writes to the Slot Control register
  * @slot_cap: cached copy of the Slot Capabilities register
@@ -105,16 +86,24 @@ struct slot {
  *	that has not yet been cleared by the user
  * @pending_events: used by the IRQ handler to save events retrieved from the
  *	Slot Status register for later consumption by the IRQ thread
+ * @state: current state machine position
+ * @lock: protects reads and writes of @state;
+ *	protects scheduling, execution and cancellation of @work
+ * @work: work item to turn the slot on or off after 5 seconds
+ *	in response to an Attention Button press
+ * @hotplug_slot: pointer to the structure registered with the PCI hotplug core
  * @ist_running: flag to keep user request waiting while IRQ thread is running
  * @request_result: result of last user request submitted to the IRQ thread
  * @requester: wait queue to wake up on completion of user request,
  *	used for synchronous slot enable/disable request via sysfs
+ *
+ * PCIe hotplug has a 1:1 relationship between controller and slot, hence
+ * unlike other drivers, the two aren't represented by separate structures.
  */
 struct controller {
 	struct mutex ctrl_lock;
 	struct pcie_device *pcie;
 	struct rw_semaphore reset_lock;
-	struct slot *slot;
 	wait_queue_head_t queue;
 	u32 slot_cap;
 	u16 slot_ctrl;
@@ -125,6 +114,10 @@ struct controller {
 	unsigned int notification_enabled:1;
 	unsigned int power_fault_detected;
 	atomic_t pending_events;
+	u8 state;
+	struct mutex lock;
+	struct delayed_work work;
+	struct hotplug_slot *hotplug_slot;
 	unsigned int ist_running;
 	int request_result;
 	wait_queue_head_t requester;
@@ -176,26 +169,26 @@ struct controller {
 #define PSN(ctrl)		(((ctrl)->slot_cap & PCI_EXP_SLTCAP_PSN) >> 19)
 
 void pciehp_request(struct controller *ctrl, int action);
-void pciehp_handle_button_press(struct slot *slot);
-void pciehp_handle_disable_request(struct slot *slot);
-void pciehp_handle_presence_or_link_change(struct slot *slot, u32 events);
-int pciehp_configure_device(struct slot *p_slot);
-void pciehp_unconfigure_device(struct slot *p_slot, bool presence);
+void pciehp_handle_button_press(struct controller *ctrl);
+void pciehp_handle_disable_request(struct controller *ctrl);
+void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events);
+int pciehp_configure_device(struct controller *ctrl);
+void pciehp_unconfigure_device(struct controller *ctrl, bool presence);
 void pciehp_queue_pushbutton_work(struct work_struct *work);
 struct controller *pcie_init(struct pcie_device *dev);
 int pcie_init_notification(struct controller *ctrl);
 void pcie_shutdown_notification(struct controller *ctrl);
 void pcie_clear_hotplug_events(struct controller *ctrl);
-int pciehp_power_on_slot(struct slot *slot);
-void pciehp_power_off_slot(struct slot *slot);
-void pciehp_get_power_status(struct slot *slot, u8 *status);
-
-void pciehp_set_attention_status(struct slot *slot, u8 status);
-void pciehp_get_latch_status(struct slot *slot, u8 *status);
-int pciehp_query_power_fault(struct slot *slot);
-void pciehp_green_led_on(struct slot *slot);
-void pciehp_green_led_off(struct slot *slot);
-void pciehp_green_led_blink(struct slot *slot);
+int pciehp_power_on_slot(struct controller *ctrl);
+void pciehp_power_off_slot(struct controller *ctrl);
+void pciehp_get_power_status(struct controller *ctrl, u8 *status);
+
+void pciehp_set_attention_status(struct controller *ctrl, u8 status);
+void pciehp_get_latch_status(struct controller *ctrl, u8 *status);
+int pciehp_query_power_fault(struct controller *ctrl);
+void pciehp_green_led_on(struct controller *ctrl);
+void pciehp_green_led_off(struct controller *ctrl);
+void pciehp_green_led_blink(struct controller *ctrl);
 bool pciehp_card_present(struct controller *ctrl);
 bool pciehp_card_present_or_link_active(struct controller *ctrl);
 int pciehp_check_link_status(struct controller *ctrl);
@@ -209,9 +202,9 @@ int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status);
 int pciehp_set_raw_indicator_status(struct hotplug_slot *h_slot, u8 status);
 int pciehp_get_raw_indicator_status(struct hotplug_slot *h_slot, u8 *status);
 
-static inline const char *slot_name(struct slot *slot)
+static inline const char *slot_name(struct controller *ctrl)
 {
-	return hotplug_slot_name(slot->hotplug_slot);
+	return hotplug_slot_name(ctrl->hotplug_slot);
 }
 
 #endif				/* _PCIEHP_H */
diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index c052efe421f3..307099c720ec 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -51,7 +51,6 @@ static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
 
 static int init_slot(struct controller *ctrl)
 {
-	struct slot *slot = ctrl->slot;
 	struct hotplug_slot *hotplug = NULL;
 	struct hotplug_slot_info *info = NULL;
 	struct hotplug_slot_ops *ops = NULL;
@@ -88,9 +87,9 @@ static int init_slot(struct controller *ctrl)
 
 	/* register this slot with the hotplug pci core */
 	hotplug->info = info;
-	hotplug->private = slot;
+	hotplug->private = ctrl;
 	hotplug->ops = ops;
-	slot->hotplug_slot = hotplug;
+	ctrl->hotplug_slot = hotplug;
 	snprintf(name, SLOT_NAME_SIZE, "%u", PSN(ctrl));
 
 	retval = pci_hp_initialize(hotplug,
@@ -108,7 +107,7 @@ static int init_slot(struct controller *ctrl)
 
 static void cleanup_slot(struct controller *ctrl)
 {
-	struct hotplug_slot *hotplug_slot = ctrl->slot->hotplug_slot;
+	struct hotplug_slot *hotplug_slot = ctrl->hotplug_slot;
 
 	pci_hp_destroy(hotplug_slot);
 	kfree(hotplug_slot->ops);
@@ -121,44 +120,44 @@ static void cleanup_slot(struct controller *ctrl)
  */
 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
 {
-	struct slot *slot = hotplug_slot->private;
-	struct pci_dev *pdev = slot->ctrl->pcie->port;
+	struct controller *ctrl = hotplug_slot->private;
+	struct pci_dev *pdev = ctrl->pcie->port;
 
 	pci_config_pm_runtime_get(pdev);
-	pciehp_set_attention_status(slot, status);
+	pciehp_set_attention_status(ctrl, status);
 	pci_config_pm_runtime_put(pdev);
 	return 0;
 }
 
 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
 {
-	struct slot *slot = hotplug_slot->private;
-	struct pci_dev *pdev = slot->ctrl->pcie->port;
+	struct controller *ctrl = hotplug_slot->private;
+	struct pci_dev *pdev = ctrl->pcie->port;
 
 	pci_config_pm_runtime_get(pdev);
-	pciehp_get_power_status(slot, value);
+	pciehp_get_power_status(ctrl, value);
 	pci_config_pm_runtime_put(pdev);
 	return 0;
 }
 
 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
 {
-	struct slot *slot = hotplug_slot->private;
-	struct pci_dev *pdev = slot->ctrl->pcie->port;
+	struct controller *ctrl = hotplug_slot->private;
+	struct pci_dev *pdev = ctrl->pcie->port;
 
 	pci_config_pm_runtime_get(pdev);
-	pciehp_get_latch_status(slot, value);
+	pciehp_get_latch_status(ctrl, value);
 	pci_config_pm_runtime_put(pdev);
 	return 0;
 }
 
 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
 {
-	struct slot *slot = hotplug_slot->private;
-	struct pci_dev *pdev = slot->ctrl->pcie->port;
+	struct controller *ctrl = hotplug_slot->private;
+	struct pci_dev *pdev = ctrl->pcie->port;
 
 	pci_config_pm_runtime_get(pdev);
-	*value = pciehp_card_present_or_link_active(slot->ctrl);
+	*value = pciehp_card_present_or_link_active(ctrl);
 	pci_config_pm_runtime_put(pdev);
 	return 0;
 }
@@ -175,20 +174,19 @@ static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
  */
 static void pciehp_check_presence(struct controller *ctrl)
 {
-	struct slot *slot = ctrl->slot;
 	bool occupied;
 
 	down_read(&ctrl->reset_lock);
-	mutex_lock(&slot->lock);
+	mutex_lock(&ctrl->lock);
 
 	occupied = pciehp_card_present_or_link_active(ctrl);
-	if ((occupied && (slot->state == OFF_STATE ||
-			  slot->state == BLINKINGON_STATE)) ||
-	    (!occupied && (slot->state == ON_STATE ||
-			   slot->state == BLINKINGOFF_STATE)))
+	if ((occupied && (ctrl->state == OFF_STATE ||
+			  ctrl->state == BLINKINGON_STATE)) ||
+	    (!occupied && (ctrl->state == ON_STATE ||
+			   ctrl->state == BLINKINGOFF_STATE)))
 		pciehp_request(ctrl, PCI_EXP_SLTSTA_PDC);
 
-	mutex_unlock(&slot->lock);
+	mutex_unlock(&ctrl->lock);
 	up_read(&ctrl->reset_lock);
 }
 
@@ -196,7 +194,6 @@ static int pciehp_probe(struct pcie_device *dev)
 {
 	int rc;
 	struct controller *ctrl;
-	struct slot *slot;
 
 	/* If this is not a "hotplug" service, we have no business here. */
 	if (dev->service != PCIE_PORT_SERVICE_HP)
@@ -234,8 +231,7 @@ static int pciehp_probe(struct pcie_device *dev)
 	}
 
 	/* Publish to user space */
-	slot = ctrl->slot;
-	rc = pci_hp_add(slot->hotplug_slot);
+	rc = pci_hp_add(ctrl->hotplug_slot);
 	if (rc) {
 		ctrl_err(ctrl, "Publication to user space failed (%d)\n", rc);
 		goto err_out_shutdown_notification;
@@ -258,7 +254,7 @@ static void pciehp_remove(struct pcie_device *dev)
 {
 	struct controller *ctrl = get_service_data(dev);
 
-	pci_hp_del(ctrl->slot->hotplug_slot);
+	pci_hp_del(ctrl->hotplug_slot);
 	pcie_shutdown_notification(ctrl);
 	cleanup_slot(ctrl);
 	pciehp_release_ctrl(ctrl);
@@ -273,14 +269,13 @@ static int pciehp_suspend(struct pcie_device *dev)
 static int pciehp_resume_noirq(struct pcie_device *dev)
 {
 	struct controller *ctrl = get_service_data(dev);
-	struct slot *slot = ctrl->slot;
 
 	/* pci_restore_state() just wrote to the Slot Control register */
 	ctrl->cmd_started = jiffies;
 	ctrl->cmd_busy = true;
 
 	/* clear spurious events from rediscovery of inserted card */
-	if (slot->state == ON_STATE || slot->state == BLINKINGOFF_STATE)
+	if (ctrl->state == ON_STATE || ctrl->state == BLINKINGOFF_STATE)
 		pcie_clear_hotplug_events(ctrl);
 
 	return 0;
diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c
index 97fa865717ec..dd6533a094a8 100644
--- a/drivers/pci/hotplug/pciehp_ctrl.c
+++ b/drivers/pci/hotplug/pciehp_ctrl.c
@@ -26,11 +26,11 @@
 #define SAFE_REMOVAL	 true
 #define SURPRISE_REMOVAL false
 
-static void set_slot_off(struct controller *ctrl, struct slot *pslot)
+static void set_slot_off(struct controller *ctrl)
 {
 	/* turn off slot, turn on Amber LED, turn off Green LED if supported*/
 	if (POWER_CTRL(ctrl)) {
-		pciehp_power_off_slot(pslot);
+		pciehp_power_off_slot(ctrl);
 
 		/*
 		 * After turning power off, we must wait for at least 1 second
@@ -40,31 +40,30 @@ static void set_slot_off(struct controller *ctrl, struct slot *pslot)
 		msleep(1000);
 	}
 
-	pciehp_green_led_off(pslot);
-	pciehp_set_attention_status(pslot, 1);
+	pciehp_green_led_off(ctrl);
+	pciehp_set_attention_status(ctrl, 1);
 }
 
 /**
  * board_added - Called after a board has been added to the system.
- * @p_slot: &slot where board is added
+ * @ctrl: PCIe hotplug controller where board is added
  *
  * Turns power on for the board.
  * Configures board.
  */
-static int board_added(struct slot *p_slot)
+static int board_added(struct controller *ctrl)
 {
 	int retval = 0;
-	struct controller *ctrl = p_slot->ctrl;
 	struct pci_bus *parent = ctrl->pcie->port->subordinate;
 
 	if (POWER_CTRL(ctrl)) {
 		/* Power on slot */
-		retval = pciehp_power_on_slot(p_slot);
+		retval = pciehp_power_on_slot(ctrl);
 		if (retval)
 			return retval;
 	}
 
-	pciehp_green_led_blink(p_slot);
+	pciehp_green_led_blink(ctrl);
 
 	/* Check link training status */
 	retval = pciehp_check_link_status(ctrl);
@@ -74,13 +73,13 @@ static int board_added(struct slot *p_slot)
 	}
 
 	/* Check for a power fault */
-	if (ctrl->power_fault_detected || pciehp_query_power_fault(p_slot)) {
-		ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(p_slot));
+	if (ctrl->power_fault_detected || pciehp_query_power_fault(ctrl)) {
+		ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(ctrl));
 		retval = -EIO;
 		goto err_exit;
 	}
 
-	retval = pciehp_configure_device(p_slot);
+	retval = pciehp_configure_device(ctrl);
 	if (retval) {
 		if (retval != -EEXIST) {
 			ctrl_err(ctrl, "Cannot add device at %04x:%02x:00\n",
@@ -89,28 +88,26 @@ static int board_added(struct slot *p_slot)
 		}
 	}
 
-	pciehp_green_led_on(p_slot);
-	pciehp_set_attention_status(p_slot, 0);
+	pciehp_green_led_on(ctrl);
+	pciehp_set_attention_status(ctrl, 0);
 	return 0;
 
 err_exit:
-	set_slot_off(ctrl, p_slot);
+	set_slot_off(ctrl);
 	return retval;
 }
 
 /**
  * remove_board - Turns off slot and LEDs
- * @p_slot: slot where board is being removed
+ * @ctrl: PCIe hotplug controller where board is being removed
  * @safe_removal: whether the board is safely removed (versus surprise removed)
  */
-static void remove_board(struct slot *p_slot, bool safe_removal)
+static void remove_board(struct controller *ctrl, bool safe_removal)
 {
-	struct controller *ctrl = p_slot->ctrl;
-
-	pciehp_unconfigure_device(p_slot, safe_removal);
+	pciehp_unconfigure_device(ctrl, safe_removal);
 
 	if (POWER_CTRL(ctrl)) {
-		pciehp_power_off_slot(p_slot);
+		pciehp_power_off_slot(ctrl);
 
 		/*
 		 * After turning power off, we must wait for at least 1 second
@@ -125,11 +122,11 @@ static void remove_board(struct slot *p_slot, bool safe_removal)
 	}
 
 	/* turn off Green LED */
-	pciehp_green_led_off(p_slot);
+	pciehp_green_led_off(ctrl);
 }
 
-static int pciehp_enable_slot(struct slot *slot);
-static int pciehp_disable_slot(struct slot *slot, bool safe_removal);
+static int pciehp_enable_slot(struct controller *ctrl);
+static int pciehp_disable_slot(struct controller *ctrl, bool safe_removal);
 
 void pciehp_request(struct controller *ctrl, int action)
 {
@@ -140,11 +137,11 @@ void pciehp_request(struct controller *ctrl, int action)
 
 void pciehp_queue_pushbutton_work(struct work_struct *work)
 {
-	struct slot *p_slot = container_of(work, struct slot, work.work);
-	struct controller *ctrl = p_slot->ctrl;
+	struct controller *ctrl = container_of(work, struct controller,
+					       work.work);
 
-	mutex_lock(&p_slot->lock);
-	switch (p_slot->state) {
+	mutex_lock(&ctrl->lock);
+	switch (ctrl->state) {
 	case BLINKINGOFF_STATE:
 		pciehp_request(ctrl, DISABLE_SLOT);
 		break;
@@ -154,30 +151,28 @@ void pciehp_queue_pushbutton_work(struct work_struct *work)
 	default:
 		break;
 	}
-	mutex_unlock(&p_slot->lock);
+	mutex_unlock(&ctrl->lock);
 }
 
-void pciehp_handle_button_press(struct slot *p_slot)
+void pciehp_handle_button_press(struct controller *ctrl)
 {
-	struct controller *ctrl = p_slot->ctrl;
-
-	mutex_lock(&p_slot->lock);
-	switch (p_slot->state) {
+	mutex_lock(&ctrl->lock);
+	switch (ctrl->state) {
 	case OFF_STATE:
 	case ON_STATE:
-		if (p_slot->state == ON_STATE) {
-			p_slot->state = BLINKINGOFF_STATE;
+		if (ctrl->state == ON_STATE) {
+			ctrl->state = BLINKINGOFF_STATE;
 			ctrl_info(ctrl, "Slot(%s): Powering off due to button press\n",
-				  slot_name(p_slot));
+				  slot_name(ctrl));
 		} else {
-			p_slot->state = BLINKINGON_STATE;
+			ctrl->state = BLINKINGON_STATE;
 			ctrl_info(ctrl, "Slot(%s) Powering on due to button press\n",
-				  slot_name(p_slot));
+				  slot_name(ctrl));
 		}
 		/* blink green LED and turn off amber */
-		pciehp_green_led_blink(p_slot);
-		pciehp_set_attention_status(p_slot, 0);
-		schedule_delayed_work(&p_slot->work, 5 * HZ);
+		pciehp_green_led_blink(ctrl);
+		pciehp_set_attention_status(ctrl, 0);
+		schedule_delayed_work(&ctrl->work, 5 * HZ);
 		break;
 	case BLINKINGOFF_STATE:
 	case BLINKINGON_STATE:
@@ -186,192 +181,184 @@ void pciehp_handle_button_press(struct slot *p_slot)
 		 * press the attention again before the 5 sec. limit
 		 * expires to cancel hot-add or hot-remove
 		 */
-		ctrl_info(ctrl, "Slot(%s): Button cancel\n", slot_name(p_slot));
-		cancel_delayed_work(&p_slot->work);
-		if (p_slot->state == BLINKINGOFF_STATE) {
-			p_slot->state = ON_STATE;
-			pciehp_green_led_on(p_slot);
+		ctrl_info(ctrl, "Slot(%s): Button cancel\n", slot_name(ctrl));
+		cancel_delayed_work(&ctrl->work);
+		if (ctrl->state == BLINKINGOFF_STATE) {
+			ctrl->state = ON_STATE;
+			pciehp_green_led_on(ctrl);
 		} else {
-			p_slot->state = OFF_STATE;
-			pciehp_green_led_off(p_slot);
+			ctrl->state = OFF_STATE;
+			pciehp_green_led_off(ctrl);
 		}
-		pciehp_set_attention_status(p_slot, 0);
+		pciehp_set_attention_status(ctrl, 0);
 		ctrl_info(ctrl, "Slot(%s): Action canceled due to button press\n",
-			  slot_name(p_slot));
+			  slot_name(ctrl));
 		break;
 	default:
 		ctrl_err(ctrl, "Slot(%s): Ignoring invalid state %#x\n",
-			 slot_name(p_slot), p_slot->state);
+			 slot_name(ctrl), ctrl->state);
 		break;
 	}
-	mutex_unlock(&p_slot->lock);
+	mutex_unlock(&ctrl->lock);
 }
 
-void pciehp_handle_disable_request(struct slot *slot)
+void pciehp_handle_disable_request(struct controller *ctrl)
 {
-	struct controller *ctrl = slot->ctrl;
-
-	mutex_lock(&slot->lock);
-	switch (slot->state) {
+	mutex_lock(&ctrl->lock);
+	switch (ctrl->state) {
 	case BLINKINGON_STATE:
 	case BLINKINGOFF_STATE:
-		cancel_delayed_work(&slot->work);
+		cancel_delayed_work(&ctrl->work);
 		break;
 	}
-	slot->state = POWEROFF_STATE;
-	mutex_unlock(&slot->lock);
+	ctrl->state = POWEROFF_STATE;
+	mutex_unlock(&ctrl->lock);
 
-	ctrl->request_result = pciehp_disable_slot(slot, SAFE_REMOVAL);
+	ctrl->request_result = pciehp_disable_slot(ctrl, SAFE_REMOVAL);
 }
 
-void pciehp_handle_presence_or_link_change(struct slot *slot, u32 events)
+void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events)
 {
-	struct controller *ctrl = slot->ctrl;
 	bool present, link_active;
 
 	/*
 	 * If the slot is on and presence or link has changed, turn it off.
 	 * Even if it's occupied again, we cannot assume the card is the same.
 	 */
-	mutex_lock(&slot->lock);
-	switch (slot->state) {
+	mutex_lock(&ctrl->lock);
+	switch (ctrl->state) {
 	case BLINKINGOFF_STATE:
-		cancel_delayed_work(&slot->work);
+		cancel_delayed_work(&ctrl->work);
 		/* fall through */
 	case ON_STATE:
-		slot->state = POWEROFF_STATE;
-		mutex_unlock(&slot->lock);
+		ctrl->state = POWEROFF_STATE;
+		mutex_unlock(&ctrl->lock);
 		if (events & PCI_EXP_SLTSTA_DLLSC)
 			ctrl_info(ctrl, "Slot(%s): Link Down\n",
-				  slot_name(slot));
+				  slot_name(ctrl));
 		if (events & PCI_EXP_SLTSTA_PDC)
 			ctrl_info(ctrl, "Slot(%s): Card not present\n",
-				  slot_name(slot));
-		pciehp_disable_slot(slot, SURPRISE_REMOVAL);
+				  slot_name(ctrl));
+		pciehp_disable_slot(ctrl, SURPRISE_REMOVAL);
 		break;
 	default:
-		mutex_unlock(&slot->lock);
+		mutex_unlock(&ctrl->lock);
 		break;
 	}
 
 	/* Turn the slot on if it's occupied or link is up */
-	mutex_lock(&slot->lock);
+	mutex_lock(&ctrl->lock);
 	present = pciehp_card_present(ctrl);
 	link_active = pciehp_check_link_active(ctrl);
 	if (!present && !link_active) {
-		mutex_unlock(&slot->lock);
+		mutex_unlock(&ctrl->lock);
 		return;
 	}
 
-	switch (slot->state) {
+	switch (ctrl->state) {
 	case BLINKINGON_STATE:
-		cancel_delayed_work(&slot->work);
+		cancel_delayed_work(&ctrl->work);
 		/* fall through */
 	case OFF_STATE:
-		slot->state = POWERON_STATE;
-		mutex_unlock(&slot->lock);
+		ctrl->state = POWERON_STATE;
+		mutex_unlock(&ctrl->lock);
 		if (present)
 			ctrl_info(ctrl, "Slot(%s): Card present\n",
-				  slot_name(slot));
+				  slot_name(ctrl));
 		if (link_active)
 			ctrl_info(ctrl, "Slot(%s): Link Up\n",
-				  slot_name(slot));
-		ctrl->request_result = pciehp_enable_slot(slot);
+				  slot_name(ctrl));
+		ctrl->request_result = pciehp_enable_slot(ctrl);
 		break;
 	default:
-		mutex_unlock(&slot->lock);
+		mutex_unlock(&ctrl->lock);
 		break;
 	}
 }
 
-static int __pciehp_enable_slot(struct slot *p_slot)
+static int __pciehp_enable_slot(struct controller *ctrl)
 {
 	u8 getstatus = 0;
-	struct controller *ctrl = p_slot->ctrl;
 
-	if (MRL_SENS(p_slot->ctrl)) {
-		pciehp_get_latch_status(p_slot, &getstatus);
+	if (MRL_SENS(ctrl)) {
+		pciehp_get_latch_status(ctrl, &getstatus);
 		if (getstatus) {
 			ctrl_info(ctrl, "Slot(%s): Latch open\n",
-				  slot_name(p_slot));
+				  slot_name(ctrl));
 			return -ENODEV;
 		}
 	}
 
-	if (POWER_CTRL(p_slot->ctrl)) {
-		pciehp_get_power_status(p_slot, &getstatus);
+	if (POWER_CTRL(ctrl)) {
+		pciehp_get_power_status(ctrl, &getstatus);
 		if (getstatus) {
 			ctrl_info(ctrl, "Slot(%s): Already enabled\n",
-				  slot_name(p_slot));
+				  slot_name(ctrl));
 			return 0;
 		}
 	}
 
-	return board_added(p_slot);
+	return board_added(ctrl);
 }
 
-static int pciehp_enable_slot(struct slot *slot)
+static int pciehp_enable_slot(struct controller *ctrl)
 {
-	struct controller *ctrl = slot->ctrl;
 	int ret;
 
 	pm_runtime_get_sync(&ctrl->pcie->port->dev);
-	ret = __pciehp_enable_slot(slot);
+	ret = __pciehp_enable_slot(ctrl);
 	if (ret && ATTN_BUTTN(ctrl))
-		pciehp_green_led_off(slot); /* may be blinking */
+		pciehp_green_led_off(ctrl); /* may be blinking */
 	pm_runtime_put(&ctrl->pcie->port->dev);
 
-	mutex_lock(&slot->lock);
-	slot->state = ret ? OFF_STATE : ON_STATE;
-	mutex_unlock(&slot->lock);
+	mutex_lock(&ctrl->lock);
+	ctrl->state = ret ? OFF_STATE : ON_STATE;
+	mutex_unlock(&ctrl->lock);
 
 	return ret;
 }
 
-static int __pciehp_disable_slot(struct slot *p_slot, bool safe_removal)
+static int __pciehp_disable_slot(struct controller *ctrl, bool safe_removal)
 {
 	u8 getstatus = 0;
-	struct controller *ctrl = p_slot->ctrl;
 
-	if (POWER_CTRL(p_slot->ctrl)) {
-		pciehp_get_power_status(p_slot, &getstatus);
+	if (POWER_CTRL(ctrl)) {
+		pciehp_get_power_status(ctrl, &getstatus);
 		if (!getstatus) {
 			ctrl_info(ctrl, "Slot(%s): Already disabled\n",
-				  slot_name(p_slot));
+				  slot_name(ctrl));
 			return -EINVAL;
 		}
 	}
 
-	remove_board(p_slot, safe_removal);
+	remove_board(ctrl, safe_removal);
 	return 0;
 }
 
-static int pciehp_disable_slot(struct slot *slot, bool safe_removal)
+static int pciehp_disable_slot(struct controller *ctrl, bool safe_removal)
 {
-	struct controller *ctrl = slot->ctrl;
 	int ret;
 
 	pm_runtime_get_sync(&ctrl->pcie->port->dev);
-	ret = __pciehp_disable_slot(slot, safe_removal);
+	ret = __pciehp_disable_slot(ctrl, safe_removal);
 	pm_runtime_put(&ctrl->pcie->port->dev);
 
-	mutex_lock(&slot->lock);
-	slot->state = OFF_STATE;
-	mutex_unlock(&slot->lock);
+	mutex_lock(&ctrl->lock);
+	ctrl->state = OFF_STATE;
+	mutex_unlock(&ctrl->lock);
 
 	return ret;
 }
 
 int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot)
 {
-	struct slot *p_slot = hotplug_slot->private;
-	struct controller *ctrl = p_slot->ctrl;
+	struct controller *ctrl = hotplug_slot->private;
 
-	mutex_lock(&p_slot->lock);
-	switch (p_slot->state) {
+	mutex_lock(&ctrl->lock);
+	switch (ctrl->state) {
 	case BLINKINGON_STATE:
 	case OFF_STATE:
-		mutex_unlock(&p_slot->lock);
+		mutex_unlock(&ctrl->lock);
 		/*
 		 * The IRQ thread becomes a no-op if the user pulls out the
 		 * card before the thread wakes up, so initialize to -ENODEV.
@@ -384,34 +371,33 @@ int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot)
 		return ctrl->request_result;
 	case POWERON_STATE:
 		ctrl_info(ctrl, "Slot(%s): Already in powering on state\n",
-			  slot_name(p_slot));
+			  slot_name(ctrl));
 		break;
 	case BLINKINGOFF_STATE:
 	case ON_STATE:
 	case POWEROFF_STATE:
 		ctrl_info(ctrl, "Slot(%s): Already enabled\n",
-			  slot_name(p_slot));
+			  slot_name(ctrl));
 		break;
 	default:
 		ctrl_err(ctrl, "Slot(%s): Invalid state %#x\n",
-			 slot_name(p_slot), p_slot->state);
+			 slot_name(ctrl), ctrl->state);
 		break;
 	}
-	mutex_unlock(&p_slot->lock);
+	mutex_unlock(&ctrl->lock);
 
 	return -ENODEV;
 }
 
 int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot)
 {
-	struct slot *p_slot = hotplug_slot->private;
-	struct controller *ctrl = p_slot->ctrl;
+	struct controller *ctrl = hotplug_slot->private;
 
-	mutex_lock(&p_slot->lock);
-	switch (p_slot->state) {
+	mutex_lock(&ctrl->lock);
+	switch (ctrl->state) {
 	case BLINKINGOFF_STATE:
 	case ON_STATE:
-		mutex_unlock(&p_slot->lock);
+		mutex_unlock(&ctrl->lock);
 		pciehp_request(ctrl, DISABLE_SLOT);
 		wait_event(ctrl->requester,
 			   !atomic_read(&ctrl->pending_events) &&
@@ -419,20 +405,20 @@ int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot)
 		return ctrl->request_result;
 	case POWEROFF_STATE:
 		ctrl_info(ctrl, "Slot(%s): Already in powering off state\n",
-			  slot_name(p_slot));
+			  slot_name(ctrl));
 		break;
 	case BLINKINGON_STATE:
 	case OFF_STATE:
 	case POWERON_STATE:
 		ctrl_info(ctrl, "Slot(%s): Already disabled\n",
-			  slot_name(p_slot));
+			  slot_name(ctrl));
 		break;
 	default:
 		ctrl_err(ctrl, "Slot(%s): Invalid state %#x\n",
-			 slot_name(p_slot), p_slot->state);
+			 slot_name(ctrl), ctrl->state);
 		break;
 	}
-	mutex_unlock(&p_slot->lock);
+	mutex_unlock(&ctrl->lock);
 
 	return -ENODEV;
 }
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 7f4173d6771a..4a17d71e15d3 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -40,7 +40,7 @@ static inline int pciehp_request_irq(struct controller *ctrl)
 	if (pciehp_poll_mode) {
 		ctrl->poll_thread = kthread_run(&pciehp_poll, ctrl,
 						"pciehp_poll-%s",
-						slot_name(ctrl->slot));
+						slot_name(ctrl));
 		return PTR_ERR_OR_ZERO(ctrl->poll_thread);
 	}
 
@@ -315,8 +315,8 @@ static int pciehp_link_enable(struct controller *ctrl)
 int pciehp_get_raw_indicator_status(struct hotplug_slot *hotplug_slot,
 				    u8 *status)
 {
-	struct slot *slot = hotplug_slot->private;
-	struct pci_dev *pdev = ctrl_dev(slot->ctrl);
+	struct controller *ctrl = hotplug_slot->private;
+	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 slot_ctrl;
 
 	pci_config_pm_runtime_get(pdev);
@@ -328,8 +328,7 @@ int pciehp_get_raw_indicator_status(struct hotplug_slot *hotplug_slot,
 
 int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status)
 {
-	struct slot *slot = hotplug_slot->private;
-	struct controller *ctrl = slot->ctrl;
+	struct controller *ctrl = hotplug_slot->private;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 slot_ctrl;
 
@@ -357,9 +356,8 @@ int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status)
 	return 0;
 }
 
-void pciehp_get_power_status(struct slot *slot, u8 *status)
+void pciehp_get_power_status(struct controller *ctrl, u8 *status)
 {
-	struct controller *ctrl = slot->ctrl;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 slot_ctrl;
 
@@ -380,9 +378,9 @@ void pciehp_get_power_status(struct slot *slot, u8 *status)
 	}
 }
 
-void pciehp_get_latch_status(struct slot *slot, u8 *status)
+void pciehp_get_latch_status(struct controller *ctrl, u8 *status)
 {
-	struct pci_dev *pdev = ctrl_dev(slot->ctrl);
+	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 slot_status;
 
 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
@@ -412,9 +410,9 @@ bool pciehp_card_present_or_link_active(struct controller *ctrl)
 	return pciehp_card_present(ctrl) || pciehp_check_link_active(ctrl);
 }
 
-int pciehp_query_power_fault(struct slot *slot)
+int pciehp_query_power_fault(struct controller *ctrl)
 {
-	struct pci_dev *pdev = ctrl_dev(slot->ctrl);
+	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 slot_status;
 
 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
@@ -424,8 +422,7 @@ int pciehp_query_power_fault(struct slot *slot)
 int pciehp_set_raw_indicator_status(struct hotplug_slot *hotplug_slot,
 				    u8 status)
 {
-	struct slot *slot = hotplug_slot->private;
-	struct controller *ctrl = slot->ctrl;
+	struct controller *ctrl = hotplug_slot->private;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
 
 	pci_config_pm_runtime_get(pdev);
@@ -435,9 +432,8 @@ int pciehp_set_raw_indicator_status(struct hotplug_slot *hotplug_slot,
 	return 0;
 }
 
-void pciehp_set_attention_status(struct slot *slot, u8 value)
+void pciehp_set_attention_status(struct controller *ctrl, u8 value)
 {
-	struct controller *ctrl = slot->ctrl;
 	u16 slot_cmd;
 
 	if (!ATTN_LED(ctrl))
@@ -461,10 +457,8 @@ void pciehp_set_attention_status(struct slot *slot, u8 value)
 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
 }
 
-void pciehp_green_led_on(struct slot *slot)
+void pciehp_green_led_on(struct controller *ctrl)
 {
-	struct controller *ctrl = slot->ctrl;
-
 	if (!PWR_LED(ctrl))
 		return;
 
@@ -475,10 +469,8 @@ void pciehp_green_led_on(struct slot *slot)
 		 PCI_EXP_SLTCTL_PWR_IND_ON);
 }
 
-void pciehp_green_led_off(struct slot *slot)
+void pciehp_green_led_off(struct controller *ctrl)
 {
-	struct controller *ctrl = slot->ctrl;
-
 	if (!PWR_LED(ctrl))
 		return;
 
@@ -489,10 +481,8 @@ void pciehp_green_led_off(struct slot *slot)
 		 PCI_EXP_SLTCTL_PWR_IND_OFF);
 }
 
-void pciehp_green_led_blink(struct slot *slot)
+void pciehp_green_led_blink(struct controller *ctrl)
 {
-	struct controller *ctrl = slot->ctrl;
-
 	if (!PWR_LED(ctrl))
 		return;
 
@@ -503,9 +493,8 @@ void pciehp_green_led_blink(struct slot *slot)
 		 PCI_EXP_SLTCTL_PWR_IND_BLINK);
 }
 
-int pciehp_power_on_slot(struct slot *slot)
+int pciehp_power_on_slot(struct controller *ctrl)
 {
-	struct controller *ctrl = slot->ctrl;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 slot_status;
 	int retval;
@@ -529,10 +518,8 @@ int pciehp_power_on_slot(struct slot *slot)
 	return retval;
 }
 
-void pciehp_power_off_slot(struct slot *slot)
+void pciehp_power_off_slot(struct controller *ctrl)
 {
-	struct controller *ctrl = slot->ctrl;
-
 	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_OFF, PCI_EXP_SLTCTL_PCC);
 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
@@ -644,7 +631,6 @@ static irqreturn_t pciehp_ist(int irq, void *dev_id)
 {
 	struct controller *ctrl = (struct controller *)dev_id;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
-	struct slot *slot = ctrl->slot;
 	irqreturn_t ret;
 	u32 events;
 
@@ -669,16 +655,16 @@ static irqreturn_t pciehp_ist(int irq, void *dev_id)
 	/* Check Attention Button Pressed */
 	if (events & PCI_EXP_SLTSTA_ABP) {
 		ctrl_info(ctrl, "Slot(%s): Attention button pressed\n",
-			  slot_name(slot));
-		pciehp_handle_button_press(slot);
+			  slot_name(ctrl));
+		pciehp_handle_button_press(ctrl);
 	}
 
 	/* Check Power Fault Detected */
 	if ((events & PCI_EXP_SLTSTA_PFD) && !ctrl->power_fault_detected) {
 		ctrl->power_fault_detected = 1;
-		ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(slot));
-		pciehp_set_attention_status(slot, 1);
-		pciehp_green_led_off(slot);
+		ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(ctrl));
+		pciehp_set_attention_status(ctrl, 1);
+		pciehp_green_led_off(ctrl);
 	}
 
 	/*
@@ -687,9 +673,9 @@ static irqreturn_t pciehp_ist(int irq, void *dev_id)
 	 */
 	down_read(&ctrl->reset_lock);
 	if (events & DISABLE_SLOT)
-		pciehp_handle_disable_request(slot);
+		pciehp_handle_disable_request(ctrl);
 	else if (events & (PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC))
-		pciehp_handle_presence_or_link_change(slot, events);
+		pciehp_handle_presence_or_link_change(ctrl, events);
 	up_read(&ctrl->reset_lock);
 
 	ret = IRQ_HANDLED;
@@ -788,8 +774,7 @@ void pcie_clear_hotplug_events(struct controller *ctrl)
  */
 int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, int probe)
 {
-	struct slot *slot = hotplug_slot->private;
-	struct controller *ctrl = slot->ctrl;
+	struct controller *ctrl = hotplug_slot->private;
 	struct pci_dev *pdev = ctrl_dev(ctrl);
 	u16 stat_mask = 0, ctrl_mask = 0;
 	int rc;
@@ -839,34 +824,6 @@ void pcie_shutdown_notification(struct controller *ctrl)
 	}
 }
 
-static int pcie_init_slot(struct controller *ctrl)
-{
-	struct pci_bus *subordinate = ctrl_dev(ctrl)->subordinate;
-	struct slot *slot;
-
-	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
-	if (!slot)
-		return -ENOMEM;
-
-	down_read(&pci_bus_sem);
-	slot->state = list_empty(&subordinate->devices) ? OFF_STATE : ON_STATE;
-	up_read(&pci_bus_sem);
-
-	slot->ctrl = ctrl;
-	mutex_init(&slot->lock);
-	INIT_DELAYED_WORK(&slot->work, pciehp_queue_pushbutton_work);
-	ctrl->slot = slot;
-	return 0;
-}
-
-static void pcie_cleanup_slot(struct controller *ctrl)
-{
-	struct slot *slot = ctrl->slot;
-
-	cancel_delayed_work_sync(&slot->work);
-	kfree(slot);
-}
-
 static inline void dbg_ctrl(struct controller *ctrl)
 {
 	struct pci_dev *pdev = ctrl->pcie->port;
@@ -890,10 +847,11 @@ struct controller *pcie_init(struct pcie_device *dev)
 	u32 slot_cap, link_cap;
 	u8 poweron;
 	struct pci_dev *pdev = dev->port;
+	struct pci_bus *subordinate = pdev->subordinate;
 
 	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
 	if (!ctrl)
-		goto abort;
+		return NULL;
 
 	ctrl->pcie = dev;
 	pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &slot_cap);
@@ -910,11 +868,17 @@ struct controller *pcie_init(struct pcie_device *dev)
 
 	ctrl->slot_cap = slot_cap;
 	mutex_init(&ctrl->ctrl_lock);
+	mutex_init(&ctrl->lock);
 	init_rwsem(&ctrl->reset_lock);
 	init_waitqueue_head(&ctrl->requester);
 	init_waitqueue_head(&ctrl->queue);
+	INIT_DELAYED_WORK(&ctrl->work, pciehp_queue_pushbutton_work);
 	dbg_ctrl(ctrl);
 
+	down_read(&pci_bus_sem);
+	ctrl->state = list_empty(&subordinate->devices) ? OFF_STATE : ON_STATE;
+	up_read(&pci_bus_sem);
+
 	/* Check if Data Link Layer Link Active Reporting is implemented */
 	pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &link_cap);
 	if (link_cap & PCI_EXP_LNKCAP_DLLLARC)
@@ -940,32 +904,24 @@ struct controller *pcie_init(struct pcie_device *dev)
 		FLAG(link_cap, PCI_EXP_LNKCAP_DLLLARC),
 		pdev->broken_cmd_compl ? " (with Cmd Compl erratum)" : "");
 
-	if (pcie_init_slot(ctrl))
-		goto abort_ctrl;
-
 	/*
 	 * If empty slot's power status is on, turn power off.  The IRQ isn't
 	 * requested yet, so avoid triggering a notification with this command.
 	 */
 	if (POWER_CTRL(ctrl)) {
-		pciehp_get_power_status(ctrl->slot, &poweron);
+		pciehp_get_power_status(ctrl, &poweron);
 		if (!pciehp_card_present_or_link_active(ctrl) && poweron) {
 			pcie_disable_notification(ctrl);
-			pciehp_power_off_slot(ctrl->slot);
+			pciehp_power_off_slot(ctrl);
 		}
 	}
 
 	return ctrl;
-
-abort_ctrl:
-	kfree(ctrl);
-abort:
-	return NULL;
 }
 
 void pciehp_release_ctrl(struct controller *ctrl)
 {
-	pcie_cleanup_slot(ctrl);
+	cancel_delayed_work_sync(&ctrl->work);
 	kfree(ctrl);
 }
 
diff --git a/drivers/pci/hotplug/pciehp_pci.c b/drivers/pci/hotplug/pciehp_pci.c
index 8da87931bd45..b9c1396db6fe 100644
--- a/drivers/pci/hotplug/pciehp_pci.c
+++ b/drivers/pci/hotplug/pciehp_pci.c
@@ -21,19 +21,18 @@
 
 /**
  * pciehp_configure_device() - enumerate PCI devices below a hotplug bridge
- * @p_slot: PCIe hotplug slot
+ * @ctrl: PCIe hotplug controller
  *
  * Enumerate PCI devices below a hotplug bridge and add them to the system.
  * Return 0 on success, %-EEXIST if the devices are already enumerated or
  * %-ENODEV if enumeration failed.
  */
-int pciehp_configure_device(struct slot *p_slot)
+int pciehp_configure_device(struct controller *ctrl)
 {
 	struct pci_dev *dev;
-	struct pci_dev *bridge = p_slot->ctrl->pcie->port;
+	struct pci_dev *bridge = ctrl->pcie->port;
 	struct pci_bus *parent = bridge->subordinate;
 	int num, ret = 0;
-	struct controller *ctrl = p_slot->ctrl;
 
 	pci_lock_rescan_remove();
 
@@ -71,7 +70,7 @@ int pciehp_configure_device(struct slot *p_slot)
 
 /**
  * pciehp_unconfigure_device() - remove PCI devices below a hotplug bridge
- * @p_slot: PCIe hotplug slot
+ * @ctrl: PCIe hotplug controller
  * @presence: whether the card is still present in the slot;
  *	true for safe removal via sysfs or an Attention Button press,
  *	false for surprise removal
@@ -80,12 +79,11 @@ int pciehp_configure_device(struct slot *p_slot)
  * them from the system.  Safely removed devices are quiesced.  Surprise
  * removed devices are marked as such to prevent further accesses.
  */
-void pciehp_unconfigure_device(struct slot *p_slot, bool presence)
+void pciehp_unconfigure_device(struct controller *ctrl, bool presence)
 {
 	struct pci_dev *dev, *temp;
-	struct pci_bus *parent = p_slot->ctrl->pcie->port->subordinate;
+	struct pci_bus *parent = ctrl->pcie->port->subordinate;
 	u16 command;
-	struct controller *ctrl = p_slot->ctrl;
 
 	ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:00\n",
 		 __func__, pci_domain_nr(parent), parent->number);
-- 
2.33.0

From 532c70e6fb9e11ac2c19df26803ea69cebc4d26f Mon Sep 17 00:00:00 2001
From: Lukas Wunner <lukas@wunner.de>
Date: Sat, 8 Sep 2018 09:59:01 +0200
Subject: [PATCH] PCI: pciehp: Rename controller struct members for clarity

Of the members which were just moved from pciehp's slot struct to the
controller struct, rename "lock" to "state_lock" and rename "work" to
"button_work" for clarity.  Perform the rename separately to the
unification of the two structs per Sinan's request.

No functional change intended.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sinan Kaya <okaya@kernel.org>

Patchset: surface-hotplug
---
 drivers/pci/hotplug/pciehp.h      | 10 +++---
 drivers/pci/hotplug/pciehp_core.c |  4 +--
 drivers/pci/hotplug/pciehp_ctrl.c | 58 +++++++++++++++----------------
 drivers/pci/hotplug/pciehp_hpc.c  |  6 ++--
 4 files changed, 39 insertions(+), 39 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index bf1c9d3a64a5..2499489158cc 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -87,9 +87,9 @@ do {									\
  * @pending_events: used by the IRQ handler to save events retrieved from the
  *	Slot Status register for later consumption by the IRQ thread
  * @state: current state machine position
- * @lock: protects reads and writes of @state;
- *	protects scheduling, execution and cancellation of @work
- * @work: work item to turn the slot on or off after 5 seconds
+ * @state_lock: protects reads and writes of @state;
+ *	protects scheduling, execution and cancellation of @button_work
+ * @button_work: work item to turn the slot on or off after 5 seconds
  *	in response to an Attention Button press
  * @hotplug_slot: pointer to the structure registered with the PCI hotplug core
  * @ist_running: flag to keep user request waiting while IRQ thread is running
@@ -115,8 +115,8 @@ struct controller {
 	unsigned int power_fault_detected;
 	atomic_t pending_events;
 	u8 state;
-	struct mutex lock;
-	struct delayed_work work;
+	struct mutex state_lock;
+	struct delayed_work button_work;
 	struct hotplug_slot *hotplug_slot;
 	unsigned int ist_running;
 	int request_result;
diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index 307099c720ec..7810000522dd 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -177,7 +177,7 @@ static void pciehp_check_presence(struct controller *ctrl)
 	bool occupied;
 
 	down_read(&ctrl->reset_lock);
-	mutex_lock(&ctrl->lock);
+	mutex_lock(&ctrl->state_lock);
 
 	occupied = pciehp_card_present_or_link_active(ctrl);
 	if ((occupied && (ctrl->state == OFF_STATE ||
@@ -186,7 +186,7 @@ static void pciehp_check_presence(struct controller *ctrl)
 			   ctrl->state == BLINKINGOFF_STATE)))
 		pciehp_request(ctrl, PCI_EXP_SLTSTA_PDC);
 
-	mutex_unlock(&ctrl->lock);
+	mutex_unlock(&ctrl->state_lock);
 	up_read(&ctrl->reset_lock);
 }
 
diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c
index dd6533a094a8..6513dd13b786 100644
--- a/drivers/pci/hotplug/pciehp_ctrl.c
+++ b/drivers/pci/hotplug/pciehp_ctrl.c
@@ -138,9 +138,9 @@ void pciehp_request(struct controller *ctrl, int action)
 void pciehp_queue_pushbutton_work(struct work_struct *work)
 {
 	struct controller *ctrl = container_of(work, struct controller,
-					       work.work);
+					       button_work.work);
 
-	mutex_lock(&ctrl->lock);
+	mutex_lock(&ctrl->state_lock);
 	switch (ctrl->state) {
 	case BLINKINGOFF_STATE:
 		pciehp_request(ctrl, DISABLE_SLOT);
@@ -151,12 +151,12 @@ void pciehp_queue_pushbutton_work(struct work_struct *work)
 	default:
 		break;
 	}
-	mutex_unlock(&ctrl->lock);
+	mutex_unlock(&ctrl->state_lock);
 }
 
 void pciehp_handle_button_press(struct controller *ctrl)
 {
-	mutex_lock(&ctrl->lock);
+	mutex_lock(&ctrl->state_lock);
 	switch (ctrl->state) {
 	case OFF_STATE:
 	case ON_STATE:
@@ -172,7 +172,7 @@ void pciehp_handle_button_press(struct controller *ctrl)
 		/* blink green LED and turn off amber */
 		pciehp_green_led_blink(ctrl);
 		pciehp_set_attention_status(ctrl, 0);
-		schedule_delayed_work(&ctrl->work, 5 * HZ);
+		schedule_delayed_work(&ctrl->button_work, 5 * HZ);
 		break;
 	case BLINKINGOFF_STATE:
 	case BLINKINGON_STATE:
@@ -182,7 +182,7 @@ void pciehp_handle_button_press(struct controller *ctrl)
 		 * expires to cancel hot-add or hot-remove
 		 */
 		ctrl_info(ctrl, "Slot(%s): Button cancel\n", slot_name(ctrl));
-		cancel_delayed_work(&ctrl->work);
+		cancel_delayed_work(&ctrl->button_work);
 		if (ctrl->state == BLINKINGOFF_STATE) {
 			ctrl->state = ON_STATE;
 			pciehp_green_led_on(ctrl);
@@ -199,20 +199,20 @@ void pciehp_handle_button_press(struct controller *ctrl)
 			 slot_name(ctrl), ctrl->state);
 		break;
 	}
-	mutex_unlock(&ctrl->lock);
+	mutex_unlock(&ctrl->state_lock);
 }
 
 void pciehp_handle_disable_request(struct controller *ctrl)
 {
-	mutex_lock(&ctrl->lock);
+	mutex_lock(&ctrl->state_lock);
 	switch (ctrl->state) {
 	case BLINKINGON_STATE:
 	case BLINKINGOFF_STATE:
-		cancel_delayed_work(&ctrl->work);
+		cancel_delayed_work(&ctrl->button_work);
 		break;
 	}
 	ctrl->state = POWEROFF_STATE;
-	mutex_unlock(&ctrl->lock);
+	mutex_unlock(&ctrl->state_lock);
 
 	ctrl->request_result = pciehp_disable_slot(ctrl, SAFE_REMOVAL);
 }
@@ -225,14 +225,14 @@ void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events)
 	 * If the slot is on and presence or link has changed, turn it off.
 	 * Even if it's occupied again, we cannot assume the card is the same.
 	 */
-	mutex_lock(&ctrl->lock);
+	mutex_lock(&ctrl->state_lock);
 	switch (ctrl->state) {
 	case BLINKINGOFF_STATE:
-		cancel_delayed_work(&ctrl->work);
+		cancel_delayed_work(&ctrl->button_work);
 		/* fall through */
 	case ON_STATE:
 		ctrl->state = POWEROFF_STATE;
-		mutex_unlock(&ctrl->lock);
+		mutex_unlock(&ctrl->state_lock);
 		if (events & PCI_EXP_SLTSTA_DLLSC)
 			ctrl_info(ctrl, "Slot(%s): Link Down\n",
 				  slot_name(ctrl));
@@ -242,26 +242,26 @@ void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events)
 		pciehp_disable_slot(ctrl, SURPRISE_REMOVAL);
 		break;
 	default:
-		mutex_unlock(&ctrl->lock);
+		mutex_unlock(&ctrl->state_lock);
 		break;
 	}
 
 	/* Turn the slot on if it's occupied or link is up */
-	mutex_lock(&ctrl->lock);
+	mutex_lock(&ctrl->state_lock);
 	present = pciehp_card_present(ctrl);
 	link_active = pciehp_check_link_active(ctrl);
 	if (!present && !link_active) {
-		mutex_unlock(&ctrl->lock);
+		mutex_unlock(&ctrl->state_lock);
 		return;
 	}
 
 	switch (ctrl->state) {
 	case BLINKINGON_STATE:
-		cancel_delayed_work(&ctrl->work);
+		cancel_delayed_work(&ctrl->button_work);
 		/* fall through */
 	case OFF_STATE:
 		ctrl->state = POWERON_STATE;
-		mutex_unlock(&ctrl->lock);
+		mutex_unlock(&ctrl->state_lock);
 		if (present)
 			ctrl_info(ctrl, "Slot(%s): Card present\n",
 				  slot_name(ctrl));
@@ -271,7 +271,7 @@ void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events)
 		ctrl->request_result = pciehp_enable_slot(ctrl);
 		break;
 	default:
-		mutex_unlock(&ctrl->lock);
+		mutex_unlock(&ctrl->state_lock);
 		break;
 	}
 }
@@ -311,9 +311,9 @@ static int pciehp_enable_slot(struct controller *ctrl)
 		pciehp_green_led_off(ctrl); /* may be blinking */
 	pm_runtime_put(&ctrl->pcie->port->dev);
 
-	mutex_lock(&ctrl->lock);
+	mutex_lock(&ctrl->state_lock);
 	ctrl->state = ret ? OFF_STATE : ON_STATE;
-	mutex_unlock(&ctrl->lock);
+	mutex_unlock(&ctrl->state_lock);
 
 	return ret;
 }
@@ -343,9 +343,9 @@ static int pciehp_disable_slot(struct controller *ctrl, bool safe_removal)
 	ret = __pciehp_disable_slot(ctrl, safe_removal);
 	pm_runtime_put(&ctrl->pcie->port->dev);
 
-	mutex_lock(&ctrl->lock);
+	mutex_lock(&ctrl->state_lock);
 	ctrl->state = OFF_STATE;
-	mutex_unlock(&ctrl->lock);
+	mutex_unlock(&ctrl->state_lock);
 
 	return ret;
 }
@@ -354,11 +354,11 @@ int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot)
 {
 	struct controller *ctrl = hotplug_slot->private;
 
-	mutex_lock(&ctrl->lock);
+	mutex_lock(&ctrl->state_lock);
 	switch (ctrl->state) {
 	case BLINKINGON_STATE:
 	case OFF_STATE:
-		mutex_unlock(&ctrl->lock);
+		mutex_unlock(&ctrl->state_lock);
 		/*
 		 * The IRQ thread becomes a no-op if the user pulls out the
 		 * card before the thread wakes up, so initialize to -ENODEV.
@@ -384,7 +384,7 @@ int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot)
 			 slot_name(ctrl), ctrl->state);
 		break;
 	}
-	mutex_unlock(&ctrl->lock);
+	mutex_unlock(&ctrl->state_lock);
 
 	return -ENODEV;
 }
@@ -393,11 +393,11 @@ int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot)
 {
 	struct controller *ctrl = hotplug_slot->private;
 
-	mutex_lock(&ctrl->lock);
+	mutex_lock(&ctrl->state_lock);
 	switch (ctrl->state) {
 	case BLINKINGOFF_STATE:
 	case ON_STATE:
-		mutex_unlock(&ctrl->lock);
+		mutex_unlock(&ctrl->state_lock);
 		pciehp_request(ctrl, DISABLE_SLOT);
 		wait_event(ctrl->requester,
 			   !atomic_read(&ctrl->pending_events) &&
@@ -418,7 +418,7 @@ int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot)
 			 slot_name(ctrl), ctrl->state);
 		break;
 	}
-	mutex_unlock(&ctrl->lock);
+	mutex_unlock(&ctrl->state_lock);
 
 	return -ENODEV;
 }
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 4a17d71e15d3..e4d6ec960630 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -868,11 +868,11 @@ struct controller *pcie_init(struct pcie_device *dev)
 
 	ctrl->slot_cap = slot_cap;
 	mutex_init(&ctrl->ctrl_lock);
-	mutex_init(&ctrl->lock);
+	mutex_init(&ctrl->state_lock);
 	init_rwsem(&ctrl->reset_lock);
 	init_waitqueue_head(&ctrl->requester);
 	init_waitqueue_head(&ctrl->queue);
-	INIT_DELAYED_WORK(&ctrl->work, pciehp_queue_pushbutton_work);
+	INIT_DELAYED_WORK(&ctrl->button_work, pciehp_queue_pushbutton_work);
 	dbg_ctrl(ctrl);
 
 	down_read(&pci_bus_sem);
@@ -921,7 +921,7 @@ struct controller *pcie_init(struct pcie_device *dev)
 
 void pciehp_release_ctrl(struct controller *ctrl)
 {
-	cancel_delayed_work_sync(&ctrl->work);
+	cancel_delayed_work_sync(&ctrl->button_work);
 	kfree(ctrl);
 }
 
-- 
2.33.0

From 30ce4d14051de5bcad38cd796e9527d2f74f8e20 Mon Sep 17 00:00:00 2001
From: Lukas Wunner <lukas@wunner.de>
Date: Sat, 8 Sep 2018 09:59:01 +0200
Subject: [PATCH] PCI: pciehp: Reshuffle controller struct for clarity

The members in pciehp's controller struct are arranged in a seemingly
arbitrary order and have grown to an amount that I no longer consider
easily graspable by contributors.

Sort the members into 5 rubrics:
* Slot Capabilities register and quirks
* Slot Control register access
* Slot Status register event handling
* state machine
* hotplug core interface

Obviously, this is just my personal bikeshed color and if anyone has a
better idea, please come forward.  Any ordering will do as long as the
information is presented in a manageable manner.

No functional change intended.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Patchset: surface-hotplug
---
 drivers/pci/hotplug/pciehp.h | 57 ++++++++++++++++++++----------------
 1 file changed, 31 insertions(+), 26 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 2499489158cc..df82a0335515 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -60,38 +60,38 @@ do {									\
 
 /**
  * struct controller - PCIe hotplug controller
- * @ctrl_lock: serializes writes to the Slot Control register
  * @pcie: pointer to the controller's PCIe port service device
- * @reset_lock: prevents access to the Data Link Layer Link Active bit in the
- *	Link Status register and to the Presence Detect State bit in the Slot
- *	Status register during a slot reset which may cause them to flap
- * @queue: wait queue to wake up on reception of a Command Completed event,
- *	used for synchronous writes to the Slot Control register
  * @slot_cap: cached copy of the Slot Capabilities register
+ * @link_active_reporting: cached copy of Data Link Layer Link Active Reporting
+ *	Capable bit in Link Capabilities register; if this bit is zero, the
+ *	Data Link Layer Link Active bit in the Link Status register will never
+ *	be set and the driver is thus confined to wait 1 second before assuming
+ *	the link to a hotplugged device is up and accessing it
  * @slot_ctrl: cached copy of the Slot Control register
- * @poll_thread: thread to poll for slot events if no IRQ is available,
- *	enabled with pciehp_poll_mode module parameter
+ * @ctrl_lock: serializes writes to the Slot Control register
  * @cmd_started: jiffies when the Slot Control register was last written;
  *	the next write is allowed 1 second later, absent a Command Completed
  *	interrupt (PCIe r4.0, sec 6.7.3.2)
  * @cmd_busy: flag set on Slot Control register write, cleared by IRQ handler
  *	on reception of a Command Completed event
- * @link_active_reporting: cached copy of Data Link Layer Link Active Reporting
- *	Capable bit in Link Capabilities register; if this bit is zero, the
- *	Data Link Layer Link Active bit in the Link Status register will never
- *	be set and the driver is thus confined to wait 1 second before assuming
- *	the link to a hotplugged device is up and accessing it
+ * @queue: wait queue to wake up on reception of a Command Completed event,
+ *	used for synchronous writes to the Slot Control register
+ * @pending_events: used by the IRQ handler to save events retrieved from the
+ *	Slot Status register for later consumption by the IRQ thread
  * @notification_enabled: whether the IRQ was requested successfully
  * @power_fault_detected: whether a power fault was detected by the hardware
  *	that has not yet been cleared by the user
- * @pending_events: used by the IRQ handler to save events retrieved from the
- *	Slot Status register for later consumption by the IRQ thread
+ * @poll_thread: thread to poll for slot events if no IRQ is available,
+ *	enabled with pciehp_poll_mode module parameter
  * @state: current state machine position
  * @state_lock: protects reads and writes of @state;
  *	protects scheduling, execution and cancellation of @button_work
  * @button_work: work item to turn the slot on or off after 5 seconds
  *	in response to an Attention Button press
  * @hotplug_slot: pointer to the structure registered with the PCI hotplug core
+ * @reset_lock: prevents access to the Data Link Layer Link Active bit in the
+ *	Link Status register and to the Presence Detect State bit in the Slot
+ *	Status register during a slot reset which may cause them to flap
  * @ist_running: flag to keep user request waiting while IRQ thread is running
  * @request_result: result of last user request submitted to the IRQ thread
  * @requester: wait queue to wake up on completion of user request,
@@ -101,23 +101,28 @@ do {									\
  * unlike other drivers, the two aren't represented by separate structures.
  */
 struct controller {
-	struct mutex ctrl_lock;
 	struct pcie_device *pcie;
-	struct rw_semaphore reset_lock;
-	wait_queue_head_t queue;
-	u32 slot_cap;
-	u16 slot_ctrl;
-	struct task_struct *poll_thread;
-	unsigned long cmd_started;	/* jiffies */
-	unsigned int cmd_busy:1;
+
+	u32 slot_cap;				/* capabilities and quirks */
 	unsigned int link_active_reporting:1;
+
+	u16 slot_ctrl;				/* control register access */
+	struct mutex ctrl_lock;
+	unsigned long cmd_started;
+	unsigned int cmd_busy:1;
+	wait_queue_head_t queue;
+
+	atomic_t pending_events;		/* event handling */
 	unsigned int notification_enabled:1;
 	unsigned int power_fault_detected;
-	atomic_t pending_events;
-	u8 state;
+	struct task_struct *poll_thread;
+
+	u8 state;				/* state machine */
 	struct mutex state_lock;
 	struct delayed_work button_work;
-	struct hotplug_slot *hotplug_slot;
+
+	struct hotplug_slot *hotplug_slot;	/* hotplug core interface */
+	struct rw_semaphore reset_lock;
 	unsigned int ist_running;
 	int request_result;
 	wait_queue_head_t requester;
-- 
2.33.0

From 7ad8cfaf3e1081427d1bf7ab95c7878fce30f18d Mon Sep 17 00:00:00 2001
From: Keith Busch <keith.busch@intel.com>
Date: Thu, 20 Sep 2018 10:27:17 -0600
Subject: [PATCH] PCI: Make link active reporting detection generic

The spec has timing requirements when waiting for a link to become active
after a conventional reset.  Implement those hard delays when waiting for
an active link so pciehp and dpc drivers don't need to duplicate this.

For devices that don't support data link layer active reporting, wait the
fixed time recommended by the PCIe spec.

Signed-off-by: Keith Busch <keith.busch@intel.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>

Patchset: surface-hotplug
---
 drivers/pci/hotplug/pciehp.h     |  6 ------
 drivers/pci/hotplug/pciehp_hpc.c | 22 ++-------------------
 drivers/pci/pci.c                | 33 ++++++++++++++++++++++++++------
 drivers/pci/pcie/dpc.c           |  4 +++-
 drivers/pci/probe.c              |  1 +
 include/linux/pci.h              |  1 +
 6 files changed, 34 insertions(+), 33 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index df82a0335515..4a6f46ca3b03 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -62,11 +62,6 @@ do {									\
  * struct controller - PCIe hotplug controller
  * @pcie: pointer to the controller's PCIe port service device
  * @slot_cap: cached copy of the Slot Capabilities register
- * @link_active_reporting: cached copy of Data Link Layer Link Active Reporting
- *	Capable bit in Link Capabilities register; if this bit is zero, the
- *	Data Link Layer Link Active bit in the Link Status register will never
- *	be set and the driver is thus confined to wait 1 second before assuming
- *	the link to a hotplugged device is up and accessing it
  * @slot_ctrl: cached copy of the Slot Control register
  * @ctrl_lock: serializes writes to the Slot Control register
  * @cmd_started: jiffies when the Slot Control register was last written;
@@ -104,7 +99,6 @@ struct controller {
 	struct pcie_device *pcie;
 
 	u32 slot_cap;				/* capabilities and quirks */
-	unsigned int link_active_reporting:1;
 
 	u16 slot_ctrl;				/* control register access */
 	struct mutex ctrl_lock;
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index e4d6ec960630..0693870a9e24 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -214,13 +214,6 @@ bool pciehp_check_link_active(struct controller *ctrl)
 	return ret;
 }
 
-static void pcie_wait_link_active(struct controller *ctrl)
-{
-	struct pci_dev *pdev = ctrl_dev(ctrl);
-
-	pcie_wait_for_link(pdev, true);
-}
-
 static bool pci_bus_check_dev(struct pci_bus *bus, int devfn)
 {
 	u32 l;
@@ -253,18 +246,9 @@ int pciehp_check_link_status(struct controller *ctrl)
 	bool found;
 	u16 lnk_status;
 
-	/*
-	 * Data Link Layer Link Active Reporting must be capable for
-	 * hot-plug capable downstream port. But old controller might
-	 * not implement it. In this case, we wait for 1000 ms.
-	*/
-	if (ctrl->link_active_reporting)
-		pcie_wait_link_active(ctrl);
-	else
-		msleep(1000);
+	if (!pcie_wait_for_link(pdev, true))
+		return -1;
 
-	/* wait 100ms before read pci conf, and try in 1s */
-	msleep(100);
 	found = pci_bus_check_dev(ctrl->pcie->port->subordinate,
 					PCI_DEVFN(0, 0));
 
@@ -881,8 +865,6 @@ struct controller *pcie_init(struct pcie_device *dev)
 
 	/* Check if Data Link Layer Link Active Reporting is implemented */
 	pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &link_cap);
-	if (link_cap & PCI_EXP_LNKCAP_DLLLARC)
-		ctrl->link_active_reporting = 1;
 
 	/* Clear all remaining event bits in Slot Status register. */
 	pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 9ebf32de8575..2d437c40f83b 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4536,21 +4536,42 @@ bool pcie_wait_for_link(struct pci_dev *pdev, bool active)
 	bool ret;
 	u16 lnk_status;
 
+	/*
+	 * Some controllers might not implement link active reporting. In this
+	 * case, we wait for 1000 + 100 ms.
+	 */
+	if (!pdev->link_active_reporting) {
+		msleep(1100);
+		return true;
+	}
+
+	/*
+	 * PCIe r4.0 sec 6.6.1, a component must enter LTSSM Detect within 20ms,
+	 * after which we should expect an link active if the reset was
+	 * successful. If so, software must wait a minimum 100ms before sending
+	 * configuration requests to devices downstream this port.
+	 *
+	 * If the link fails to activate, either the device was physically
+	 * removed or the link is permanently failed.
+	 */
+	if (active)
+		msleep(20);
 	for (;;) {
 		pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status);
 		ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA);
 		if (ret == active)
-			return true;
+			break;
 		if (timeout <= 0)
 			break;
 		msleep(10);
 		timeout -= 10;
 	}
-
-	pci_info(pdev, "Data Link Layer Link Active not %s in 1000 msec\n",
-		 active ? "set" : "cleared");
-
-	return false;
+	if (active && ret)
+		msleep(100);
+	else if (ret != active)
+		pci_info(pdev, "Data Link Layer Link Active not %s in 1000 msec\n",
+			active ? "set" : "cleared");
+	return ret == active;
 }
 
 void pci_reset_secondary_bus(struct pci_dev *dev)
diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c
index 118b5bcae42e..87f8d8628d94 100644
--- a/drivers/pci/pcie/dpc.c
+++ b/drivers/pci/pcie/dpc.c
@@ -93,10 +93,12 @@ static pci_ers_result_t dpc_reset_link(struct pci_dev *pdev)
 	pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS,
 			      PCI_EXP_DPC_STATUS_TRIGGER);
 
+	if (!pcie_wait_for_link(pdev, true))
+		return PCI_ERS_RESULT_DISCONNECT;
+
 	return PCI_ERS_RESULT_RECOVERED;
 }
 
-
 static void dpc_process_rp_pio_error(struct dpc_dev *dpc)
 {
 	struct device *dev = &dpc->dev->device;
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 113b7bdf86dd..79ca1a28b991 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -769,6 +769,7 @@ static void pci_set_bus_speed(struct pci_bus *bus)
 
 		pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
 		bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
+		bridge->link_active_reporting = !!(linkcap & PCI_EXP_LNKCAP_DLLLARC);
 
 		pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
 		pcie_update_link_speed(bus, linksta);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index ec6c48ecd7d5..74c8e9190fed 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -407,6 +407,7 @@ struct pci_dev {
 	unsigned int	has_secondary_link:1;
 	unsigned int	non_compliant_bars:1;	/* Broken BARs; ignore them */
 	unsigned int	is_probed:1;		/* Device probing in progress */
+	unsigned int	link_active_reporting:1;/* Device capable of reporting link active */
 	pci_dev_flags_t dev_flags;
 	atomic_t	enable_cnt;	/* pci_enable_device has been called */
 
-- 
2.33.0

From 9f416805546783005a9a0ee5762cbf9e7e5f0f22 Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg@linux.intel.com>
Date: Thu, 27 Sep 2018 16:53:53 -0500
Subject: [PATCH] PCI: Do not skip power-managed bridges in pci_enable_wake()

Commit baecc470d5fd ("PCI / PM: Skip bridges in pci_enable_wake()") changed
pci_enable_wake() so that all bridges are skipped when wakeup is enabled
(or disabled) with the reasoning that bridges can only signal wakeup on
behalf of their subordinate devices.

However, there are bridges that can signal wakeup themselves.  For example
PCIe downstream and root ports supporting hotplug may signal wakeup upon
hotplug event.

For this reason change pci_enable_wake() so that it skips all bridges
except those that we power manage (->bridge_d3 is set).  Those are the ones
that can go into low power states and may need to signal wakeup.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Patchset: surface-hotplug
---
 drivers/pci/pci.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 2d437c40f83b..4a874e8fa1d5 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -2151,10 +2151,13 @@ static int __pci_enable_wake(struct pci_dev *dev, pci_power_t state, bool enable
 	int ret = 0;
 
 	/*
-	 * Bridges can only signal wakeup on behalf of subordinate devices,
-	 * but that is set up elsewhere, so skip them.
+	 * Bridges that are not power-manageable directly only signal
+	 * wakeup on behalf of subordinate devices which is set up
+	 * elsewhere, so skip them. However, bridges that are
+	 * power-manageable may signal wakeup for themselves (for example,
+	 * on a hotplug event) and they need to be covered here.
 	 */
-	if (pci_has_subordinate(dev))
+	if (!pci_power_manageable(dev))
 		return 0;
 
 	/* Don't do the same thing twice in a row for one device. */
-- 
2.33.0

From 0cda3ae7ae8ec40180f6019552e95d7ce4900089 Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg@linux.intel.com>
Date: Thu, 27 Sep 2018 16:38:19 -0500
Subject: [PATCH] PCI: pciehp: Disable hotplug interrupt during suspend

When PCIe hotplug port is transitioned into D3hot, the link to the
downstream component will go down. If hotplug interrupt generation is
enabled when that happens, it will trigger immediately, waking up the
system and bringing the link back up.

To prevent this, disable hotplug interrupt generation when system suspend
is entered. This does not prevent wakeup from low power states according
to PCIe 4.0 spec section 6.7.3.4:

  Software enables a hot-plug event to generate a wakeup event by
  enabling software notification of the event as described in Section
  6.7.3.1. Note that in order for software to disable interrupt generation
  while keeping wakeup generation enabled, the Hot-Plug Interrupt Enable
  bit must be cleared.

So as long as we have set the slot event mask accordingly, wakeup should
work even if slot interrupt is disabled. The port should trigger wake and
then send PME to the root port when the PCIe hierarchy is brought back up.

Limit this to systems using native PME mechanism to make sure older Apple
systems depending on commit e3354628c376 ("PCI: pciehp: Support interrupts
sent from D3hot") still continue working.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Patchset: surface-hotplug
---
 drivers/pci/hotplug/pciehp.h      |  2 ++
 drivers/pci/hotplug/pciehp_core.c | 18 ++++++++++++++++++
 drivers/pci/hotplug/pciehp_hpc.c  | 10 ++++++++++
 3 files changed, 30 insertions(+)

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 4a6f46ca3b03..80d3f76c1193 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -178,6 +178,8 @@ struct controller *pcie_init(struct pcie_device *dev);
 int pcie_init_notification(struct controller *ctrl);
 void pcie_shutdown_notification(struct controller *ctrl);
 void pcie_clear_hotplug_events(struct controller *ctrl);
+void pcie_enable_interrupt(struct controller *ctrl);
+void pcie_disable_interrupt(struct controller *ctrl);
 int pciehp_power_on_slot(struct controller *ctrl);
 void pciehp_power_off_slot(struct controller *ctrl);
 void pciehp_get_power_status(struct controller *ctrl, u8 *status);
diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index 7810000522dd..8e6e4ce869fb 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -261,8 +261,23 @@ static void pciehp_remove(struct pcie_device *dev)
 }
 
 #ifdef CONFIG_PM
+static bool pme_is_native(struct pcie_device *dev)
+{
+	const struct pci_host_bridge *host;
+
+	host = pci_find_host_bridge(dev->port->bus);
+	return pcie_ports_native || host->native_pme;
+}
+
 static int pciehp_suspend(struct pcie_device *dev)
 {
+	/*
+	 * Disable hotplug interrupt so that it does not trigger
+	 * immediately when the downstream link goes down.
+	 */
+	if (pme_is_native(dev))
+		pcie_disable_interrupt(get_service_data(dev));
+
 	return 0;
 }
 
@@ -285,6 +300,9 @@ static int pciehp_resume(struct pcie_device *dev)
 {
 	struct controller *ctrl = get_service_data(dev);
 
+	if (pme_is_native(dev))
+		pcie_enable_interrupt(ctrl);
+
 	pciehp_check_presence(ctrl);
 
 	return 0;
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 0693870a9e24..b5c7f5ef597a 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -748,6 +748,16 @@ void pcie_clear_hotplug_events(struct controller *ctrl)
 				   PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC);
 }
 
+void pcie_enable_interrupt(struct controller *ctrl)
+{
+	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_HPIE, PCI_EXP_SLTCTL_HPIE);
+}
+
+void pcie_disable_interrupt(struct controller *ctrl)
+{
+	pcie_write_cmd(ctrl, 0, PCI_EXP_SLTCTL_HPIE);
+}
+
 /*
  * pciehp has a 1:1 bus:slot relationship so we ultimately want a secondary
  * bus reset of the bridge, but at the same time we want to ensure that it is
-- 
2.33.0

From 13e6690919312b21b54bef2585e94d57b9dd6a75 Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg@linux.intel.com>
Date: Thu, 27 Sep 2018 16:41:46 -0500
Subject: [PATCH] PCI: pciehp: Do not handle events if interrupts are masked

PCIe native hotplug shares MSI vector with native PME so the interrupt
handler might get called even the hotplug interrupt is masked. In that case
we should not handle any events because the interrupt was not meant for us.

Modify the PCIe hotplug interrupt handler to check this accordingly and
bail out if it finds out that the interrupt was not about hotplug.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>

Patchset: surface-hotplug
---
 drivers/pci/hotplug/pciehp_hpc.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index b5c7f5ef597a..242b9f30210a 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -518,9 +518,11 @@ static irqreturn_t pciehp_isr(int irq, void *dev_id)
 	u16 status, events = 0;
 
 	/*
-	 * Interrupts only occur in D3hot or shallower (PCIe r4.0, sec 6.7.3.4).
+	 * Interrupts only occur in D3hot or shallower and only if enabled
+	 * in the Slot Control register (PCIe r4.0, sec 6.7.3.4).
 	 */
-	if (pdev->current_state == PCI_D3cold)
+	if (pdev->current_state == PCI_D3cold ||
+	    (!(ctrl->slot_ctrl & PCI_EXP_SLTCTL_HPIE) && !pciehp_poll_mode))
 		return IRQ_NONE;
 
 	/*
-- 
2.33.0

From 07af128ff0d589536dbd523b944ec4942b1380d0 Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg@linux.intel.com>
Date: Thu, 27 Sep 2018 16:41:47 -0500
Subject: [PATCH] PCI/portdrv: Resume upon exit from system suspend if left
 runtime suspended

Currently we try to keep PCIe ports runtime suspended over system suspend
if possible. This mostly happens when entering suspend-to-idle because
there is no need to re-configure wake settings.

This causes problems if the parent port goes into D3cold and it gets
resumed upon exit from system suspend. This may happen for example if the
port is part of PCIe switch and the same switch is connected to a PCIe
endpoint that needs to be resumed. The way exit from D3cold works according
PCIe 4.0 spec 5.3.1.4.2 is that power is restored and cold reset is
signaled. After this the device is in D0unitialized state keeping PME
context if it supports wake from D3cold.

The problem occurs when a PCIe hotplug port is left suspended and the
parent port goes into D3cold and back to D0: the port keeps its PME context
but since everything else is reset back to defaults (D0unitialized) it is
not set to detect hotplug events anymore.

For this reason change the PCIe portdrv power management logic so that it
is fine to keep the port runtime suspended over system suspend but it needs
to be resumed upon exit to make sure it gets properly re-initialized.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Patchset: surface-hotplug
---
 drivers/pci/pcie/portdrv_pci.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/pcie/portdrv_pci.c b/drivers/pci/pcie/portdrv_pci.c
index 23a5a0c2c3fe..5badf8a1ce0a 100644
--- a/drivers/pci/pcie/portdrv_pci.c
+++ b/drivers/pci/pcie/portdrv_pci.c
@@ -109,8 +109,8 @@ static int pcie_portdrv_probe(struct pci_dev *dev,
 
 	pci_save_state(dev);
 
-	dev_pm_set_driver_flags(&dev->dev, DPM_FLAG_SMART_SUSPEND |
-					   DPM_FLAG_LEAVE_SUSPENDED);
+	dev_pm_set_driver_flags(&dev->dev, DPM_FLAG_NEVER_SKIP |
+					   DPM_FLAG_SMART_SUSPEND);
 
 	if (pci_bridge_d3_possible(dev)) {
 		/*
-- 
2.33.0

From a0c6895a935960370f4109ac525bd5691e160dd5 Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg@linux.intel.com>
Date: Thu, 27 Sep 2018 16:41:48 -0500
Subject: [PATCH] PCI/portdrv: Add runtime PM hooks for port service drivers

When PCIe port is runtime suspended/resumed some extra steps might be
needed to be executed from the port service driver side. For instance we
may need to disable PCIe hotplug interrupt to prevent it from triggering
immediately when PCIe link to the downstream component goes down.

To make the above possible add optional ->runtime_suspend() and
->runtime_resume() callbacks to struct pcie_port_service_driver and call
them for each port service in runtime suspend/resume callbacks of portdrv.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: adjust "slot->state" for 5790a9c78e78 ("PCI: pciehp: Unify
controller and slot structs")]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Patchset: surface-hotplug
---
 drivers/pci/pcie/portdrv.h      |  4 ++++
 drivers/pci/pcie/portdrv_core.c | 20 ++++++++++++++++++++
 drivers/pci/pcie/portdrv_pci.c  | 10 ++++------
 3 files changed, 28 insertions(+), 6 deletions(-)

diff --git a/drivers/pci/pcie/portdrv.h b/drivers/pci/pcie/portdrv.h
index 2498b2d34009..abfdc2ae7979 100644
--- a/drivers/pci/pcie/portdrv.h
+++ b/drivers/pci/pcie/portdrv.h
@@ -76,6 +76,8 @@ struct pcie_port_service_driver {
 	int (*suspend) (struct pcie_device *dev);
 	int (*resume_noirq) (struct pcie_device *dev);
 	int (*resume) (struct pcie_device *dev);
+	int (*runtime_suspend) (struct pcie_device *dev);
+	int (*runtime_resume) (struct pcie_device *dev);
 
 	/* Device driver may resume normal operations */
 	void (*error_resume)(struct pci_dev *dev);
@@ -109,6 +111,8 @@ int pcie_port_device_register(struct pci_dev *dev);
 int pcie_port_device_suspend(struct device *dev);
 int pcie_port_device_resume_noirq(struct device *dev);
 int pcie_port_device_resume(struct device *dev);
+int pcie_port_device_runtime_suspend(struct device *dev);
+int pcie_port_device_runtime_resume(struct device *dev);
 #endif
 void pcie_port_device_remove(struct pci_dev *dev);
 int __must_check pcie_port_bus_register(void);
diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c
index 7c37d815229e..6542c48c7f59 100644
--- a/drivers/pci/pcie/portdrv_core.c
+++ b/drivers/pci/pcie/portdrv_core.c
@@ -395,6 +395,26 @@ int pcie_port_device_resume(struct device *dev)
 	size_t off = offsetof(struct pcie_port_service_driver, resume);
 	return device_for_each_child(dev, &off, pm_iter);
 }
+
+/**
+ * pcie_port_device_runtime_suspend - runtime suspend port services
+ * @dev: PCI Express port to handle
+ */
+int pcie_port_device_runtime_suspend(struct device *dev)
+{
+	size_t off = offsetof(struct pcie_port_service_driver, runtime_suspend);
+	return device_for_each_child(dev, &off, pm_iter);
+}
+
+/**
+ * pcie_port_device_runtime_resume - runtime resume port services
+ * @dev: PCI Express port to handle
+ */
+int pcie_port_device_runtime_resume(struct device *dev)
+{
+	size_t off = offsetof(struct pcie_port_service_driver, runtime_resume);
+	return device_for_each_child(dev, &off, pm_iter);
+}
 #endif /* PM */
 
 static int remove_iter(struct device *dev, void *data)
diff --git a/drivers/pci/pcie/portdrv_pci.c b/drivers/pci/pcie/portdrv_pci.c
index 5badf8a1ce0a..59d2567e2db2 100644
--- a/drivers/pci/pcie/portdrv_pci.c
+++ b/drivers/pci/pcie/portdrv_pci.c
@@ -45,12 +45,10 @@ __setup("pcie_ports=", pcie_port_setup);
 #ifdef CONFIG_PM
 static int pcie_port_runtime_suspend(struct device *dev)
 {
-	return to_pci_dev(dev)->bridge_d3 ? 0 : -EBUSY;
-}
+	if (!to_pci_dev(dev)->bridge_d3)
+		return -EBUSY;
 
-static int pcie_port_runtime_resume(struct device *dev)
-{
-	return 0;
+	return pcie_port_device_runtime_suspend(dev);
 }
 
 static int pcie_port_runtime_idle(struct device *dev)
@@ -73,7 +71,7 @@ static const struct dev_pm_ops pcie_portdrv_pm_ops = {
 	.restore_noirq	= pcie_port_device_resume_noirq,
 	.restore	= pcie_port_device_resume,
 	.runtime_suspend = pcie_port_runtime_suspend,
-	.runtime_resume	= pcie_port_runtime_resume,
+	.runtime_resume	= pcie_port_device_runtime_resume,
 	.runtime_idle	= pcie_port_runtime_idle,
 };
 
-- 
2.33.0

From 4f1cb78419da17be25ef12927a7d36e6e88ac5c2 Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg@linux.intel.com>
Date: Thu, 27 Sep 2018 16:41:49 -0500
Subject: [PATCH] PCI: pciehp: Implement runtime PM callbacks

Basically we need to do the same thing when runtime suspending than with
system sleep so re-use those operations here. This makes sure hotplug
interrupt does not trigger immediately when the link goes down.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Patchset: surface-hotplug
---
 drivers/pci/hotplug/pciehp_core.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index 8e6e4ce869fb..e5de25ebc4cf 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -307,6 +307,22 @@ static int pciehp_resume(struct pcie_device *dev)
 
 	return 0;
 }
+
+static int pciehp_runtime_resume(struct pcie_device *dev)
+{
+	struct controller *ctrl = get_service_data(dev);
+
+	/* pci_restore_state() just wrote to the Slot Control register */
+	ctrl->cmd_started = jiffies;
+	ctrl->cmd_busy = true;
+
+	/* clear spurious events from rediscovery of inserted card */
+	if ((ctrl->state == ON_STATE || ctrl->state == BLINKINGOFF_STATE) &&
+	     pme_is_native(dev))
+		pcie_clear_hotplug_events(ctrl);
+
+	return pciehp_resume(dev);
+}
 #endif /* PM */
 
 static struct pcie_port_service_driver hpdriver_portdrv = {
@@ -321,6 +337,8 @@ static struct pcie_port_service_driver hpdriver_portdrv = {
 	.suspend	= pciehp_suspend,
 	.resume_noirq	= pciehp_resume_noirq,
 	.resume		= pciehp_resume,
+	.runtime_suspend = pciehp_suspend,
+	.runtime_resume	= pciehp_runtime_resume,
 #endif	/* PM */
 };
 
-- 
2.33.0

From 9541f17a98ab418042a5a4053b6ac3cf2299390d Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg@linux.intel.com>
Date: Thu, 27 Sep 2018 16:57:05 -0500
Subject: [PATCH] ACPI / property: Allow multiple property compatible _DSD
 entries

It is possible to have _DSD entries where the data is compatible with
device properties format but are using different GUID for various reasons.
In addition to that there can be many such _DSD entries for a single device
such as for PCIe root port used to host a Thunderbolt hierarchy:

    Scope (\_SB.PCI0.RP21)
    {
        Name (_DSD, Package () {
            ToUUID ("6211e2c0-58a3-4af3-90e1-927a4e0c55a4"),
            Package () {
                Package () {"HotPlugSupportInD3", 1}
            },

            ToUUID ("efcc06cc-73ac-4bc3-bff0-76143807c389"),
            Package () {
                Package () {"ExternalFacingPort", 1},
                Package () {"UID", 0 }
            }
        })
    }

More information about these new _DSD entries can be found in:

  https://docs.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports

To make these available for drivers via unified device property APIs,
modify ACPI property core so that it supports multiple _DSD entries
organized in a linked list. We also store GUID of each _DSD entry in struct
acpi_device_properties in case there is need to differentiate between
entries. The supported GUIDs are then listed in prp_guids array.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>

Patchset: surface-hotplug
---
 drivers/acpi/property.c     | 94 +++++++++++++++++++++++++++----------
 drivers/acpi/x86/apple.c    |  2 +-
 drivers/gpio/gpiolib-acpi.c |  2 +-
 include/acpi/acpi_bus.h     |  8 +++-
 include/linux/acpi.h        |  9 ++++
 5 files changed, 86 insertions(+), 29 deletions(-)

diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
index 27db1a968241..9a679ae50089 100644
--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -24,11 +24,12 @@ static int acpi_data_get_property_array(const struct acpi_device_data *data,
 					acpi_object_type type,
 					const union acpi_object **obj);
 
-/* ACPI _DSD device properties GUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */
-static const guid_t prp_guid =
+static const guid_t prp_guids[] = {
+	/* ACPI _DSD device properties GUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */
 	GUID_INIT(0xdaffd814, 0x6eba, 0x4d8c,
-		  0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01);
-/* ACPI _DSD data subnodes GUID: dbb8e3e6-5886-4ba6-8795-1319f52a966b */
+		  0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01),
+};
+
 static const guid_t ads_guid =
 	GUID_INIT(0xdbb8e3e6, 0x5886, 0x4ba6,
 		  0x87, 0x95, 0x13, 0x19, 0xf5, 0x2a, 0x96, 0x6b);
@@ -56,6 +57,7 @@ static bool acpi_nondev_subnode_extract(const union acpi_object *desc,
 	dn->name = link->package.elements[0].string.pointer;
 	dn->fwnode.ops = &acpi_data_fwnode_ops;
 	dn->parent = parent;
+	INIT_LIST_HEAD(&dn->data.properties);
 	INIT_LIST_HEAD(&dn->data.subnodes);
 
 	result = acpi_extract_properties(desc, &dn->data);
@@ -288,6 +290,35 @@ static void acpi_init_of_compatible(struct acpi_device *adev)
 	adev->flags.of_compatible_ok = 1;
 }
 
+static bool acpi_is_property_guid(const guid_t *guid)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(prp_guids); i++) {
+		if (guid_equal(guid, &prp_guids[i]))
+			return true;
+	}
+
+	return false;
+}
+
+struct acpi_device_properties *
+acpi_data_add_props(struct acpi_device_data *data, const guid_t *guid,
+		    const union acpi_object *properties)
+{
+	struct acpi_device_properties *props;
+
+	props = kzalloc(sizeof(*props), GFP_KERNEL);
+	if (props) {
+		INIT_LIST_HEAD(&props->list);
+		props->guid = guid;
+		props->properties = properties;
+		list_add_tail(&props->list, &data->properties);
+	}
+
+	return props;
+}
+
 static bool acpi_extract_properties(const union acpi_object *desc,
 				    struct acpi_device_data *data)
 {
@@ -312,7 +343,7 @@ static bool acpi_extract_properties(const union acpi_object *desc,
 		    properties->type != ACPI_TYPE_PACKAGE)
 			break;
 
-		if (!guid_equal((guid_t *)guid->buffer.pointer, &prp_guid))
+		if (!acpi_is_property_guid((guid_t *)guid->buffer.pointer))
 			continue;
 
 		/*
@@ -320,13 +351,13 @@ static bool acpi_extract_properties(const union acpi_object *desc,
 		 * package immediately following it.
 		 */
 		if (!acpi_properties_format_valid(properties))
-			break;
+			continue;
 
-		data->properties = properties;
-		return true;
+		acpi_data_add_props(data, (const guid_t *)guid->buffer.pointer,
+				    properties);
 	}
 
-	return false;
+	return !list_empty(&data->properties);
 }
 
 void acpi_init_properties(struct acpi_device *adev)
@@ -336,6 +367,7 @@ void acpi_init_properties(struct acpi_device *adev)
 	acpi_status status;
 	bool acpi_of = false;
 
+	INIT_LIST_HEAD(&adev->data.properties);
 	INIT_LIST_HEAD(&adev->data.subnodes);
 
 	if (!adev->handle)
@@ -398,11 +430,16 @@ static void acpi_destroy_nondev_subnodes(struct list_head *list)
 
 void acpi_free_properties(struct acpi_device *adev)
 {
+	struct acpi_device_properties *props, *tmp;
+
 	acpi_destroy_nondev_subnodes(&adev->data.subnodes);
 	ACPI_FREE((void *)adev->data.pointer);
 	adev->data.of_compatible = NULL;
 	adev->data.pointer = NULL;
-	adev->data.properties = NULL;
+	list_for_each_entry_safe(props, tmp, &adev->data.properties, list) {
+		list_del(&props->list);
+		kfree(props);
+	}
 }
 
 /**
@@ -427,32 +464,37 @@ static int acpi_data_get_property(const struct acpi_device_data *data,
 				  const char *name, acpi_object_type type,
 				  const union acpi_object **obj)
 {
-	const union acpi_object *properties;
-	int i;
+	const struct acpi_device_properties *props;
 
 	if (!data || !name)
 		return -EINVAL;
 
-	if (!data->pointer || !data->properties)
+	if (!data->pointer || list_empty(&data->properties))
 		return -EINVAL;
 
-	properties = data->properties;
-	for (i = 0; i < properties->package.count; i++) {
-		const union acpi_object *propname, *propvalue;
-		const union acpi_object *property;
+	list_for_each_entry(props, &data->properties, list) {
+		const union acpi_object *properties;
+		unsigned int i;
 
-		property = &properties->package.elements[i];
+		properties = props->properties;
+		for (i = 0; i < properties->package.count; i++) {
+			const union acpi_object *propname, *propvalue;
+			const union acpi_object *property;
 
-		propname = &property->package.elements[0];
-		propvalue = &property->package.elements[1];
+			property = &properties->package.elements[i];
 
-		if (!strcmp(name, propname->string.pointer)) {
-			if (type != ACPI_TYPE_ANY && propvalue->type != type)
-				return -EPROTO;
-			if (obj)
-				*obj = propvalue;
+			propname = &property->package.elements[0];
+			propvalue = &property->package.elements[1];
 
-			return 0;
+			if (!strcmp(name, propname->string.pointer)) {
+				if (type != ACPI_TYPE_ANY &&
+				    propvalue->type != type)
+					return -EPROTO;
+				if (obj)
+					*obj = propvalue;
+
+				return 0;
+			}
 		}
 	}
 	return -EINVAL;
diff --git a/drivers/acpi/x86/apple.c b/drivers/acpi/x86/apple.c
index 51b4cf9f25da..130df1c8ed7d 100644
--- a/drivers/acpi/x86/apple.c
+++ b/drivers/acpi/x86/apple.c
@@ -132,8 +132,8 @@ void acpi_extract_apple_properties(struct acpi_device *adev)
 	}
 	WARN_ON(free_space != (void *)newprops + newsize);
 
-	adev->data.properties = newprops;
 	adev->data.pointer = newprops;
+	acpi_data_add_props(&adev->data, &apple_prp_guid, newprops);
 
 out_free:
 	ACPI_FREE(props);
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index b018909a4e46..ebe5245ed6c3 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -1300,7 +1300,7 @@ int acpi_gpio_count(struct device *dev, const char *con_id)
 bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id)
 {
 	/* Never allow fallback if the device has properties */
-	if (adev->data.properties || adev->driver_gpios)
+	if (acpi_dev_has_props(adev) || adev->driver_gpios)
 		return false;
 
 	return con_id == NULL;
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 8b19618bad0a..af01d052f736 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -347,10 +347,16 @@ struct acpi_device_physical_node {
 	bool put_online:1;
 };
 
+struct acpi_device_properties {
+	const guid_t *guid;
+	const union acpi_object *properties;
+	struct list_head list;
+};
+
 /* ACPI Device Specific Data (_DSD) */
 struct acpi_device_data {
 	const union acpi_object *pointer;
-	const union acpi_object *properties;
+	struct list_head properties;
 	const union acpi_object *of_compatible;
 	struct list_head subnodes;
 };
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 1a37748766b7..50a09003bb43 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1083,6 +1083,15 @@ static inline int acpi_node_get_property_reference(
 		NR_FWNODE_REFERENCE_ARGS, args);
 }
 
+static inline bool acpi_dev_has_props(const struct acpi_device *adev)
+{
+	return !list_empty(&adev->data.properties);
+}
+
+struct acpi_device_properties *
+acpi_data_add_props(struct acpi_device_data *data, const guid_t *guid,
+		    const union acpi_object *properties);
+
 int acpi_node_prop_get(const struct fwnode_handle *fwnode, const char *propname,
 		       void **valptr);
 int acpi_dev_prop_read_single(struct acpi_device *adev,
-- 
2.33.0

From eb0dcd2b98c1bf73188056ec38f1d959bb43c55a Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg@linux.intel.com>
Date: Thu, 27 Sep 2018 16:57:14 -0500
Subject: [PATCH] PCI / ACPI: Whitelist D3 for more PCIe hotplug ports

In order to have better power management for Thunderbolt PCIe chains,
Windows enables power management for native PCIe hotplug ports if there is
the following ACPI _DSD attached to the root port:

  Name (_DSD, Package () {
      ToUUID ("6211e2c0-58a3-4af3-90e1-927a4e0c55a4"),
      Package () {
          Package () {"HotPlugSupportInD3", 1}
      }
  })

This is also documented in:

  https://docs.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports#identifying-pcie-root-ports-supporting-hot-plug-in-d3

Do the same in Linux by introducing new firmware PM callback
(->bridge_d3()) and then implement it for ACPI based systems so that the
above property is checked.

There is one catch, though. The initial pci_dev->bridge_d3 is set before
the root port has ACPI companion bound (the device is not added to the PCI
bus either) so we need to look up the ACPI companion manually in that case
in acpi_pci_bridge_d3().

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Patchset: surface-hotplug
---
 drivers/acpi/property.c |  3 +++
 drivers/pci/pci-acpi.c  | 41 +++++++++++++++++++++++++++++++++++++++++
 drivers/pci/pci.c       |  9 +++++++++
 drivers/pci/pci.h       |  3 +++
 4 files changed, 56 insertions(+)

diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
index 9a679ae50089..6497f04f9551 100644
--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -28,6 +28,9 @@ static const guid_t prp_guids[] = {
 	/* ACPI _DSD device properties GUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */
 	GUID_INIT(0xdaffd814, 0x6eba, 0x4d8c,
 		  0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01),
+	/* Hotplug in D3 GUID: 6211e2c0-58a3-4af3-90e1-927a4e0c55a4 */
+	GUID_INIT(0x6211e2c0, 0x58a3, 0x4af3,
+		  0x90, 0xe1, 0x92, 0x7a, 0x4e, 0x0c, 0x55, 0xa4),
 };
 
 static const guid_t ads_guid =
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index 2c46f7dcd2f5..1516327a8459 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -519,6 +519,46 @@ static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
 	return PCI_POWER_ERROR;
 }
 
+static struct acpi_device *acpi_pci_find_companion(struct device *dev);
+
+static bool acpi_pci_bridge_d3(struct pci_dev *dev)
+{
+	const struct fwnode_handle *fwnode;
+	struct acpi_device *adev;
+	struct pci_dev *root;
+	u8 val;
+
+	if (!dev->is_hotplug_bridge)
+		return false;
+
+	/*
+	 * Look for a special _DSD property for the root port and if it
+	 * is set we know the hierarchy behind it supports D3 just fine.
+	 */
+	root = pci_find_pcie_root_port(dev);
+	if (!root)
+		return false;
+
+	adev = ACPI_COMPANION(&root->dev);
+	if (root == dev) {
+		/*
+		 * It is possible that the ACPI companion is not yet bound
+		 * for the root port so look it up manually here.
+		 */
+		if (!adev && !pci_dev_is_added(root))
+			adev = acpi_pci_find_companion(&root->dev);
+	}
+
+	if (!adev)
+		return false;
+
+	fwnode = acpi_fwnode_handle(adev);
+	if (fwnode_property_read_u8(fwnode, "HotPlugSupportInD3", &val))
+		return false;
+
+	return val == 1;
+}
+
 static bool acpi_pci_power_manageable(struct pci_dev *dev)
 {
 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
@@ -636,6 +676,7 @@ static bool acpi_pci_need_resume(struct pci_dev *dev)
 }
 
 static const struct pci_platform_pm_ops acpi_pci_platform_pm = {
+	.bridge_d3 = acpi_pci_bridge_d3,
 	.is_manageable = acpi_pci_power_manageable,
 	.set_state = acpi_pci_set_power_state,
 	.get_state = acpi_pci_get_power_state,
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 4a874e8fa1d5..a60eb5780cc0 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -793,6 +793,11 @@ static inline bool platform_pci_need_resume(struct pci_dev *dev)
 	return pci_platform_pm ? pci_platform_pm->need_resume(dev) : false;
 }
 
+static inline bool platform_pci_bridge_d3(struct pci_dev *dev)
+{
+	return pci_platform_pm ? pci_platform_pm->bridge_d3(dev) : false;
+}
+
 /**
  * pci_raw_set_power_state - Use PCI PM registers to set the power state of
  *                           given PCI device
@@ -2551,6 +2556,10 @@ bool pci_bridge_d3_possible(struct pci_dev *bridge)
 		if (bridge->is_thunderbolt)
 			return true;
 
+		/* Platform might know better if the bridge supports D3 */
+		if (platform_pci_bridge_d3(bridge))
+			return true;
+
 		/*
 		 * Hotplug ports handled natively by the OS were not validated
 		 * by vendors for runtime D3 at least until 2018 because there
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 39725b71300f..ee3e94c6ea6c 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -40,6 +40,8 @@ int pci_bus_error_reset(struct pci_dev *dev);
 /**
  * struct pci_platform_pm_ops - Firmware PM callbacks
  *
+ * @bridge_d3: Does the bridge allow entering into D3
+ *
  * @is_manageable: returns 'true' if given device is power manageable by the
  *		   platform firmware
  *
@@ -61,6 +63,7 @@ int pci_bus_error_reset(struct pci_dev *dev);
  * these callbacks are mandatory.
  */
 struct pci_platform_pm_ops {
+	bool (*bridge_d3)(struct pci_dev *dev);
 	bool (*is_manageable)(struct pci_dev *dev);
 	int (*set_state)(struct pci_dev *dev, pci_power_t state);
 	pci_power_t (*get_state)(struct pci_dev *dev);
-- 
2.33.0

From 3072251f32aaa54852d19bff828f6deaad80679d Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg@linux.intel.com>
Date: Mon, 7 Jan 2019 16:09:40 +0300
Subject: [PATCH] PCI: pciehp: Assign ctrl->slot_ctrl before writing it to
 hardware

Shameerali reported that running v4.20-rc1 as QEMU guest, the PCIe hotplug
port times out during boot:

  pciehp 0000:00:01.0:pcie004: Timeout on hotplug command 0x03f1 (issued 1016 msec ago)
  pciehp 0000:00:01.0:pcie004: Timeout on hotplug command 0x03f1 (issued 1024 msec ago)
  pciehp 0000:00:01.0:pcie004: Failed to check link status
  pciehp 0000:00:01.0:pcie004: Timeout on hotplug command 0x02f1 (issued 2520 msec ago)

The issue was bisected down to commit 720d6a671a6e ("PCI: pciehp: Do not
handle events if interrupts are masked") and was further analyzed by the
reporter to be caused by the fact that pciehp first updates the hardware
and only then cache the ctrl->slot_ctrl in pcie_do_write_cmd().  If the
interrupt happens before we cache the value, pciehp_isr() reads value 0 and
decides that the interrupt was not meant for it causing the above timeout
to trigger.

Fix by moving ctrl->slot_ctrl assignment to happen before it is written to
the hardware.

Fixes: 720d6a671a6e ("PCI: pciehp: Do not handle events if interrupts are masked")
Link: https://lore.kernel.org/linux-pci/5FC3163CFD30C246ABAA99954A238FA8387DD344@FRAEML521-MBX.china.huawei.com
Reported-by: Shameerali Kolothum Thodi <shameerali.kolothum.thodi@huawei.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Patchset: surface-hotplug
---
 drivers/pci/hotplug/pciehp_hpc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 242b9f30210a..7074d4923811 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -156,9 +156,9 @@ static void pcie_do_write_cmd(struct controller *ctrl, u16 cmd,
 	slot_ctrl |= (cmd & mask);
 	ctrl->cmd_busy = 1;
 	smp_mb();
+	ctrl->slot_ctrl = slot_ctrl;
 	pcie_capability_write_word(pdev, PCI_EXP_SLTCTL, slot_ctrl);
 	ctrl->cmd_started = jiffies;
-	ctrl->slot_ctrl = slot_ctrl;
 
 	/*
 	 * Controllers with the Intel CF118 and similar errata advertise
-- 
2.33.0

From 9f934ab11c0f6078709402a2af415916d73e6dd9 Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg@linux.intel.com>
Date: Thu, 31 Jan 2019 20:07:46 +0300
Subject: [PATCH] PCI: pciehp: Disable Data Link Layer State Changed event on
 suspend

Commit 0e157e528604 ("PCI/PME: Implement runtime PM callbacks") tried to
solve an issue where the hierarchy immediately wakes up when it is
transitioned into D3cold.  However, it turns out to prevent PME
propagation on some systems that do not support D3cold.

I looked more closely at what might cause the immediate wakeup.  It happens
when the ACPI power resource of the root port is turned off.  The AML code
associated with the _OFF() method of the ACPI power resource starts a PCIe
L2/L3 Ready transition and waits for it to complete.  Right after the L2/L3
Ready transition is started the root port receives a PME from the
downstream port.

The simplest hierarchy where this happens looks like this:

  00:1d.0 PCIe Root Port
    ^
    |
    v
    05:00.0 PCIe switch #1 upstream port
      06:01.0 PCIe switch #1 downstream hotplug port
        ^
        |
        v
        08:00.0 PCIe switch #2 upstream port

It seems that the PCIe link between the two switches, before
PME_Turn_Off/PME_TO_Ack is complete for the whole hierarchy, goes
inactive and triggers PME towards the root port bringing it back to D0.
The L2/L3 Ready sequence is described in PCIe r4.0 spec sections 5.2 and
5.3.3 but unfortunately they do not state what happens if DLLSCE is
enabled during the sequence.

Disabling Data Link Layer State Changed event (DLLSCE) seems to prevent
the issue and still allows the downstream hotplug port to notice when a
device is plugged/unplugged.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=202593
Fixes: 0e157e528604 ("PCI/PME: Implement runtime PM callbacks")
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CC: stable@vger.kernel.org	# v4.20+

Patchset: surface-hotplug
---
 drivers/pci/hotplug/pciehp_hpc.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 7074d4923811..a37ff79a6e9e 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -752,12 +752,25 @@ void pcie_clear_hotplug_events(struct controller *ctrl)
 
 void pcie_enable_interrupt(struct controller *ctrl)
 {
-	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_HPIE, PCI_EXP_SLTCTL_HPIE);
+	u16 mask;
+
+	mask = PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_DLLSCE;
+	pcie_write_cmd(ctrl, mask, mask);
 }
 
 void pcie_disable_interrupt(struct controller *ctrl)
 {
-	pcie_write_cmd(ctrl, 0, PCI_EXP_SLTCTL_HPIE);
+	u16 mask;
+
+	/*
+	 * Mask hot-plug interrupt to prevent it triggering immediately
+	 * when the link goes inactive (we still get PME when any of the
+	 * enabled events is detected). Same goes with Link Layer State
+	 * changed event which generates PME immediately when the link goes
+	 * inactive so mask it as well.
+	 */
+	mask = PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_DLLSCE;
+	pcie_write_cmd(ctrl, 0, mask);
 }
 
 /*
-- 
2.33.0

From 5e8db923ba9b2b98164029d3212206338c539ac0 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Thu, 29 Oct 2020 22:04:38 +0100
Subject: [PATCH] PCI: Allow D3cold for hot-plug ports on Surface Books

The Microsoft Surface Book series of devices have a tablet part (so
called clipboard) that can be detached from the base of the device.
While the clipboard contains the CPU, the base can contain a discrete
GPU (dGPU). This dGPU is connected via a PCIe hot-plug port.

Currently D3cold is disallowed for all hot-plug ports. On the Surface
Book 2 and 3, this leads to increased power consumption during suspend
and when the dGPU is not used (i.e. runtime suspended). This can be
observed not only in battery drain, but also by the dGPU getting notably
warm while suspended and not in D3cold.

Testing shows that the Surface Books behave well with D3cold enabled for
hot-plug ports, alleviating the aforementioned issues. Thus white-list
D3cold for hot-plug ports on those devices.

Note: PCIe hot-plug signalling while the device is in D3cold is handled
via ACPI, out-of-band interrupts, and the surface_hotplug driver
(combined). The device will work without the surface_hotplug driver,
however, device removal/addition will only be detected on device resume.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Patchset: surface-hotplug
---
 drivers/pci/pci.c | 31 +++++++++++++++++++++++++++++--
 1 file changed, 29 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index a60eb5780cc0..65bb9c2c1a5b 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -2523,6 +2523,32 @@ static const struct dmi_system_id bridge_d3_blacklist[] = {
 	{ }
 };
 
+static const struct dmi_system_id bridge_d3_hotplug_whitelist[] = {
+#ifdef CONFIG_X86
+	{
+		/*
+		 * Microsoft Surface Books have a hot-plug root port for the
+		 * discrete GPU (the device containing it can be detached form
+		 * the top-part, containing the cpu).
+		 *
+		 * If this discrete GPU is not transitioned into D3cold for
+		 * suspend, the device will become notably warm and also
+		 * consume a lot more power than desirable.
+		 *
+		 * We assume that since those devices have been confirmed
+		 * working with D3, future Surface devices will too. So let's
+		 * keep this match generic.
+		 */
+		.ident = "Microsoft Surface",
+		.matches = {
+			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Surface"),
+		},
+	},
+#endif
+	{ }
+};
+
 /**
  * pci_bridge_d3_possible - Is it possible to put the bridge into D3
  * @bridge: Bridge to check
@@ -2563,10 +2589,11 @@ bool pci_bridge_d3_possible(struct pci_dev *bridge)
 		/*
 		 * Hotplug ports handled natively by the OS were not validated
 		 * by vendors for runtime D3 at least until 2018 because there
-		 * was no OS support.
+		 * was no OS support. Explicitly whitelist systems that have
+		 * been confirmed working.
 		 */
 		if (bridge->is_hotplug_bridge)
-			return false;
+			return dmi_check_system(bridge_d3_hotplug_whitelist);
 
 		if (dmi_check_system(bridge_d3_blacklist))
 			return false;
-- 
2.33.0

From 122c5495b34f3c6eb16e4a8c6736ae4c110d6da7 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Sat, 31 Oct 2020 20:46:33 +0100
Subject: [PATCH] PCI: Add sysfs attribute for PCI device power state

While most PCI power-states can be queried from user-space via lspci,
this has some limits. Specifically, lspci fails to provide an accurate
value when the device is in D3cold as it has to resume the device before
it can access its power state via the configuration space, leading to it
reporting D0 or another on-state. Thus lspci can, for example, not be
used to diagnose power-consumption issues for devices that can enter
D3cold or to ensure that devices properly enter D3cold at all.

To alleviate this issue, introduce a new sysfs device attribute for the
PCI power state, showing the current power state as seen by the kernel.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Patchset: surface-hotplug
---
 Documentation/ABI/testing/sysfs-bus-pci |  9 +++++++++
 drivers/pci/pci-sysfs.c                 | 12 ++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
index 44d4b2be92fd..daded06ae017 100644
--- a/Documentation/ABI/testing/sysfs-bus-pci
+++ b/Documentation/ABI/testing/sysfs-bus-pci
@@ -323,3 +323,12 @@ Description:
 
 		This is similar to /sys/bus/pci/drivers_autoprobe, but
 		affects only the VFs associated with a specific PF.
+
+What:		/sys/bus/pci/devices/.../power_state
+Date:		November 2020
+Contact:	Linux PCI developers <linux-pci@vger.kernel.org>
+Description:
+		This file contains the current PCI power state of the device.
+		The value comes from the PCI kernel device state and can be one
+		of: "unknown", "error", "D0", D1", "D2", "D3hot", "D3cold".
+		The file is read only.
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 1edf5a1836ea..ee1518650d55 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -124,6 +124,17 @@ static ssize_t cpulistaffinity_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(cpulistaffinity);
 
+/* PCI power state */
+static ssize_t power_state_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct pci_dev *pci_dev = to_pci_dev(dev);
+	pci_power_t state = READ_ONCE(pci_dev->current_state);
+
+	return sprintf(buf, "%s\n", pci_power_name(state));
+}
+static DEVICE_ATTR_RO(power_state);
+
 /* show resources */
 static ssize_t resource_show(struct device *dev, struct device_attribute *attr,
 			     char *buf)
@@ -745,6 +756,7 @@ static ssize_t driver_override_show(struct device *dev,
 static DEVICE_ATTR_RW(driver_override);
 
 static struct attribute *pci_dev_attrs[] = {
+	&dev_attr_power_state.attr,
 	&dev_attr_resource.attr,
 	&dev_attr_vendor.attr,
 	&dev_attr_device.attr,
-- 
2.33.0

From d264fe11e99e5209c7f876691e41872f9fa3e4d5 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Mon, 14 Dec 2020 20:50:59 +0100
Subject: [PATCH] platform/x86: Add Surface Hotplug driver

Add a driver to handle out-of-band hot-plug signaling for the discrete
GPU (dGPU) on Microsoft Surface Book 2 and 3 devices. This driver is
required to properly detect hot-plugging of the dGPU and relay the
appropriate signal to the PCIe hot-plug driver core.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Patchset: surface-hotplug
---
 drivers/platform/x86/Kconfig           |  19 ++
 drivers/platform/x86/Makefile          |   1 +
 drivers/platform/x86/surface_hotplug.c | 282 +++++++++++++++++++++++++
 3 files changed, 302 insertions(+)
 create mode 100644 drivers/platform/x86/surface_hotplug.c

diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 9aed8f6941cc..d48bf3b2fdfd 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -708,6 +708,25 @@ config ACPI_WMI
 	  It is safe to enable this driver even if your DSDT doesn't define
 	  any ACPI-WMI devices.
 
+config SURFACE_HOTPLUG
+	tristate "Surface Hot-Plug Driver"
+	depends on GPIOLIB
+	help
+	  Driver for out-of-band hot-plug event signaling on Microsoft Surface
+	  devices with hot-pluggable PCIe cards.
+
+	  This driver is used on Surface Book (2 and 3) devices with a
+	  hot-pluggable discrete GPU (dGPU). When not in use, the dGPU on those
+	  devices can enter D3cold, which prevents in-band (standard) PCIe
+	  hot-plug signaling. Thus, without this driver, detaching the base
+	  containing the dGPU will not correctly update the state of the
+	  corresponding PCIe device if it is in D3cold. This driver adds support
+	  for out-of-band hot-plug notifications, ensuring that the device state
+	  is properly updated even when the device in question is in D3cold.
+
+	  Select M or Y here, if you want to (fully) support hot-plugging of
+	  dGPU devices on the Surface Book 2 and/or 3 during D3cold.
+
 config WMI_BMOF
 	tristate "WMI embedded Binary MOF driver"
 	depends on ACPI_WMI
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 2737a78616c8..d08f7e254d47 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -89,6 +89,7 @@ obj-$(CONFIG_SURFACE_PRO3_BUTTON)	+= surfacepro3_button.o
 obj-$(CONFIG_SURFACE_3_BUTTON)	+= surface3_button.o
 obj-$(CONFIG_SURFACE_3_POWER_OPREGION) += surface3_power.o
 obj-$(CONFIG_SURFACE_GPE)	+= surface_gpe.o
+obj-$(CONFIG_SURFACE_HOTPLUG)	+= surface_hotplug.o
 obj-$(CONFIG_SURFACE_BOOK1_DGPU_SWITCH)	+= sb1_dgpu_sw.o
 obj-$(CONFIG_INTEL_PUNIT_IPC)  += intel_punit_ipc.o
 obj-$(CONFIG_INTEL_BXTWC_PMIC_TMU)	+= intel_bxtwc_tmu.o
diff --git a/drivers/platform/x86/surface_hotplug.c b/drivers/platform/x86/surface_hotplug.c
new file mode 100644
index 000000000000..cfcc15cfbacb
--- /dev/null
+++ b/drivers/platform/x86/surface_hotplug.c
@@ -0,0 +1,282 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Surface Book (2 and later) hot-plug driver.
+ *
+ * Surface Book devices (can) have a hot-pluggable discrete GPU (dGPU). This
+ * driver is responsible for out-of-band hot-plug event signaling on these
+ * devices. It is specifically required when the hot-plug device is in D3cold
+ * and can thus not generate PCIe hot-plug events itself.
+ *
+ * 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>
+ */
+
+#include <linux/acpi.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+
+static const struct acpi_gpio_params shps_base_presence_int   = { 0, 0, false };
+static const struct acpi_gpio_params shps_base_presence       = { 1, 0, false };
+static const struct acpi_gpio_params shps_device_power_int    = { 2, 0, false };
+static const struct acpi_gpio_params shps_device_power        = { 3, 0, false };
+static const struct acpi_gpio_params shps_device_presence_int = { 4, 0, false };
+static const struct acpi_gpio_params shps_device_presence     = { 5, 0, false };
+
+static const struct acpi_gpio_mapping shps_acpi_gpios[] = {
+	{ "base_presence-int-gpio",   &shps_base_presence_int,   1 },
+	{ "base_presence-gpio",       &shps_base_presence,       1 },
+	{ "device_power-int-gpio",    &shps_device_power_int,    1 },
+	{ "device_power-gpio",        &shps_device_power,        1 },
+	{ "device_presence-int-gpio", &shps_device_presence_int, 1 },
+	{ "device_presence-gpio",     &shps_device_presence,     1 },
+	{ },
+};
+
+/* 5515a847-ed55-4b27-8352-cd320e10360a */
+static const guid_t shps_dsm_guid =
+	GUID_INIT(0x5515a847, 0xed55, 0x4b27, 0x83, 0x52, 0xcd, 0x32, 0x0e, 0x10, 0x36, 0x0a);
+
+#define SHPS_DSM_REVISION		1
+
+enum shps_dsm_fn {
+	SHPS_DSM_FN_PCI_NUM_ENTRIES	= 0x01,
+	SHPS_DSM_FN_PCI_GET_ENTRIES	= 0x02,
+	SHPS_DSM_FN_IRQ_BASE_PRESENCE	= 0x03,
+	SHPS_DSM_FN_IRQ_DEVICE_POWER	= 0x04,
+	SHPS_DSM_FN_IRQ_DEVICE_PRESENCE	= 0x05,
+};
+
+enum shps_irq_type {
+	/* NOTE: Must be in order of enum shps_dsm_fn above. */
+	SHPS_IRQ_TYPE_BASE_PRESENCE	= 0,
+	SHPS_IRQ_TYPE_DEVICE_POWER	= 1,
+	SHPS_IRQ_TYPE_DEVICE_PRESENCE	= 2,
+	SHPS_NUM_IRQS,
+};
+
+static const char *const shps_gpio_names[] = {
+	[SHPS_IRQ_TYPE_BASE_PRESENCE]	= "base_presence",
+	[SHPS_IRQ_TYPE_DEVICE_POWER]	= "device_power",
+	[SHPS_IRQ_TYPE_DEVICE_PRESENCE]	= "device_presence",
+};
+
+struct shps_device {
+	struct mutex lock[SHPS_NUM_IRQS];  /* Protects update in shps_dsm_notify_irq() */
+	struct gpio_desc *gpio[SHPS_NUM_IRQS];
+	unsigned int irq[SHPS_NUM_IRQS];
+};
+
+#define SHPS_IRQ_NOT_PRESENT		((unsigned int)-1)
+
+static enum shps_dsm_fn shps_dsm_fn_for_irq(enum shps_irq_type type)
+{
+	return SHPS_DSM_FN_IRQ_BASE_PRESENCE + type;
+}
+
+static void shps_dsm_notify_irq(struct platform_device *pdev, enum shps_irq_type type)
+{
+	struct shps_device *sdev = platform_get_drvdata(pdev);
+	acpi_handle handle = ACPI_HANDLE(&pdev->dev);
+	union acpi_object *result;
+	union acpi_object param;
+	int value;
+
+	mutex_lock(&sdev->lock[type]);
+
+	value = gpiod_get_value_cansleep(sdev->gpio[type]);
+	if (value < 0) {
+		mutex_unlock(&sdev->lock[type]);
+		dev_err(&pdev->dev, "failed to get gpio: %d (irq=%d)\n", type, value);
+		return;
+	}
+
+	dev_dbg(&pdev->dev, "IRQ notification via DSM (irq=%d, value=%d)\n", type, value);
+
+	param.type = ACPI_TYPE_INTEGER;
+	param.integer.value = value;
+
+	result = acpi_evaluate_dsm(handle, &shps_dsm_guid, SHPS_DSM_REVISION,
+				   shps_dsm_fn_for_irq(type), &param);
+
+	if (!result) {
+		dev_err(&pdev->dev, "IRQ notification via DSM failed (irq=%d, gpio=%d)\n",
+			type, value);
+
+	} else if (result->type != ACPI_TYPE_BUFFER) {
+		dev_err(&pdev->dev,
+			"IRQ notification via DSM failed: unexpected result type (irq=%d, gpio=%d)\n",
+			type, value);
+
+	} else if (result->buffer.length != 1 || result->buffer.pointer[0] != 0) {
+		dev_err(&pdev->dev,
+			"IRQ notification via DSM failed: unexpected result value (irq=%d, gpio=%d)\n",
+			type, value);
+	}
+
+	mutex_unlock(&sdev->lock[type]);
+
+	if (result)
+		ACPI_FREE(result);
+}
+
+static irqreturn_t shps_handle_irq(int irq, void *data)
+{
+	struct platform_device *pdev = data;
+	struct shps_device *sdev = platform_get_drvdata(pdev);
+	int type;
+
+	/* Figure out which IRQ we're handling. */
+	for (type = 0; type < SHPS_NUM_IRQS; type++)
+		if (irq == sdev->irq[type])
+			break;
+
+	/* We should have found our interrupt, if not: this is a bug. */
+	if (WARN(type >= SHPS_NUM_IRQS, "invalid IRQ number: %d\n", irq))
+		return IRQ_HANDLED;
+
+	/* Forward interrupt to ACPI via DSM. */
+	shps_dsm_notify_irq(pdev, type);
+	return IRQ_HANDLED;
+}
+
+static int shps_setup_irq(struct platform_device *pdev, enum shps_irq_type type)
+{
+	unsigned long flags = IRQF_ONESHOT | IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING;
+	struct shps_device *sdev = platform_get_drvdata(pdev);
+	struct gpio_desc *gpiod;
+	acpi_handle handle = ACPI_HANDLE(&pdev->dev);
+	const char *irq_name;
+	const int dsm = shps_dsm_fn_for_irq(type);
+	int status, irq;
+
+	/*
+	 * Only set up interrupts that we actually need: The Surface Book 3
+	 * does not have a DSM for base presence, so don't set up an interrupt
+	 * for that.
+	 */
+	if (!acpi_check_dsm(handle, &shps_dsm_guid, SHPS_DSM_REVISION, BIT(dsm))) {
+		dev_dbg(&pdev->dev, "IRQ notification via DSM not present (irq=%d)\n", type);
+		return 0;
+	}
+
+	gpiod = devm_gpiod_get(&pdev->dev, shps_gpio_names[type], GPIOD_ASIS);
+	if (IS_ERR(gpiod))
+		return PTR_ERR(gpiod);
+
+	irq = gpiod_to_irq(gpiod);
+	if (irq < 0)
+		return irq;
+
+	irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "shps-irq-%d", type);
+	if (!irq_name)
+		return -ENOMEM;
+
+	status = devm_request_threaded_irq(&pdev->dev, irq, NULL, shps_handle_irq,
+					   flags, irq_name, pdev);
+	if (status)
+		return status;
+
+	dev_dbg(&pdev->dev, "set up irq %d as type %d\n", irq, type);
+
+	sdev->gpio[type] = gpiod;
+	sdev->irq[type] = irq;
+
+	return 0;
+}
+
+static int surface_hotplug_remove(struct platform_device *pdev)
+{
+	struct shps_device *sdev = platform_get_drvdata(pdev);
+	int i;
+
+	/* Ensure that IRQs have been fully handled and won't trigger any more. */
+	for (i = 0; i < SHPS_NUM_IRQS; i++) {
+		if (sdev->irq[i] != SHPS_IRQ_NOT_PRESENT)
+			disable_irq(sdev->irq[i]);
+
+		mutex_destroy(&sdev->lock[i]);
+	}
+
+	return 0;
+}
+
+static int surface_hotplug_probe(struct platform_device *pdev)
+{
+	struct shps_device *sdev;
+	int status, i;
+
+	/*
+	 * The MSHW0153 device is also present on the Surface Laptop 3,
+	 * however that doesn't have a hot-pluggable PCIe device. It also
+	 * doesn't have any GPIO interrupts/pins under the MSHW0153, so filter
+	 * it out here.
+	 */
+	if (gpiod_count(&pdev->dev, NULL) < 0)
+		return -ENODEV;
+
+	status = devm_acpi_dev_add_driver_gpios(&pdev->dev, shps_acpi_gpios);
+	if (status)
+		return status;
+
+	sdev = devm_kzalloc(&pdev->dev, sizeof(*sdev), GFP_KERNEL);
+	if (!sdev)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, sdev);
+
+	/*
+	 * Initialize IRQs so that we can safely call surface_hotplug_remove()
+	 * on errors.
+	 */
+	for (i = 0; i < SHPS_NUM_IRQS; i++)
+		sdev->irq[i] = SHPS_IRQ_NOT_PRESENT;
+
+	/* Set up IRQs. */
+	for (i = 0; i < SHPS_NUM_IRQS; i++) {
+		mutex_init(&sdev->lock[i]);
+
+		status = shps_setup_irq(pdev, i);
+		if (status) {
+			dev_err(&pdev->dev, "failed to set up IRQ %d: %d\n", i, status);
+			goto err;
+		}
+	}
+
+	/* Ensure everything is up-to-date. */
+	for (i = 0; i < SHPS_NUM_IRQS; i++)
+		if (sdev->irq[i] != SHPS_IRQ_NOT_PRESENT)
+			shps_dsm_notify_irq(pdev, i);
+
+	return 0;
+
+err:
+	surface_hotplug_remove(pdev);
+	return status;
+}
+
+static const struct acpi_device_id surface_hotplug_acpi_match[] = {
+	{ "MSHW0153", 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(acpi, surface_hotplug_acpi_match);
+
+static struct platform_driver surface_hotplug_driver = {
+	.probe = surface_hotplug_probe,
+	.remove = surface_hotplug_remove,
+	.driver = {
+		.name = "surface_hotplug",
+		.acpi_match_table = surface_hotplug_acpi_match,
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+	},
+};
+module_platform_driver(surface_hotplug_driver);
+
+MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
+MODULE_DESCRIPTION("Surface Hot-Plug Signaling Driver for Surface Book Devices");
+MODULE_LICENSE("GPL");
-- 
2.33.0

From 655eceec8421630a914f5edd1d433e9770c01be9 Mon Sep 17 00:00:00 2001
From: Maximilian Luz <luzmaximilian@gmail.com>
Date: Fri, 2 Jul 2021 14:41:34 +0200
Subject: [PATCH] Revert "Revert "PCI: PM: Do not read power state in
 pci_enable_device_flags()""

This reverts commit 2bf73bce3df9517c4144f05ea0a80dbfeaa36933.

Patchset: surface-hotplug
---
 drivers/pci/pci.c | 16 +++-------------
 1 file changed, 3 insertions(+), 13 deletions(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 65bb9c2c1a5b..5f3f35d314c3 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1590,20 +1590,10 @@ static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags)
 	int err;
 	int i, bars = 0;
 
-	/*
-	 * Power state could be unknown at this point, either due to a fresh
-	 * boot or a device removal call.  So get the current power state
-	 * so that things like MSI message writing will behave as expected
-	 * (e.g. if the device really is in D0 at enable time).
-	 */
-	if (dev->pm_cap) {
-		u16 pmcsr;
-		pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
-		dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
-	}
-
-	if (atomic_inc_return(&dev->enable_cnt) > 1)
+	if (atomic_inc_return(&dev->enable_cnt) > 1) {
+		pci_update_current_state(dev, dev->current_state);
 		return 0;		/* already enabled */
+	}
 
 	bridge = pci_upstream_bridge(dev);
 	if (bridge)
-- 
2.33.0