linux-surface/patches/6.0/0008-surface-typecover.patch

From faaa02f3a030264f021373f9f83e29d34b2e5497 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jonas=20Dre=C3=9Fler?= <verdre@v0yd.nl>
Date: Thu, 5 Nov 2020 13:09:45 +0100
Subject: [PATCH] hid/multitouch: Turn off Type Cover keyboard backlight when
 suspending

The Type Cover for Microsoft Surface devices supports a special usb
control request to disable or enable the built-in keyboard backlight.
On Windows, this request happens when putting the device into suspend or
resuming it, without it the backlight of the Type Cover will remain
enabled for some time even though the computer is suspended, which looks
weird to the user.

So add support for this special usb control request to hid-multitouch,
which is the driver that's handling the Type Cover.

The reason we have to use a pm_notifier for this instead of the usual
suspend/resume methods is that those won't get called in case the usb
device is already autosuspended.

Also, if the device is autosuspended, we have to briefly autoresume it
in order to send the request. Doing that should be fine, the usb-core
driver does something similar during suspend inside choose_wakeup().

To make sure we don't send that request to every device but only to
devices which support it, add a new quirk
MT_CLS_WIN_8_MS_SURFACE_TYPE_COVER to hid-multitouch. For now this quirk
is only enabled for the usb id of the Surface Pro 2017 Type Cover, which
is where I confirmed that it's working.

Patchset: surface-typecover
---
 drivers/hid/hid-multitouch.c | 100 ++++++++++++++++++++++++++++++++++-
 1 file changed, 98 insertions(+), 2 deletions(-)

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 91a4d3fc30e0..458537bf4a8e 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -34,7 +34,10 @@
 #include <linux/device.h>
 #include <linux/hid.h>
 #include <linux/module.h>
+#include <linux/pm_runtime.h>
 #include <linux/slab.h>
+#include <linux/suspend.h>
+#include <linux/usb.h>
 #include <linux/input/mt.h>
 #include <linux/jiffies.h>
 #include <linux/string.h>
@@ -47,6 +50,7 @@ MODULE_DESCRIPTION("HID multitouch panels");
 MODULE_LICENSE("GPL");
 
 #include "hid-ids.h"
+#include "usbhid/usbhid.h"
 
 /* quirks to control the device */
 #define MT_QUIRK_NOT_SEEN_MEANS_UP	BIT(0)
@@ -71,12 +75,15 @@ MODULE_LICENSE("GPL");
 #define MT_QUIRK_SEPARATE_APP_REPORT	BIT(19)
 #define MT_QUIRK_FORCE_MULTI_INPUT	BIT(20)
 #define MT_QUIRK_DISABLE_WAKEUP		BIT(21)
+#define MT_QUIRK_HAS_TYPE_COVER_BACKLIGHT	BIT(22)
 
 #define MT_INPUTMODE_TOUCHSCREEN	0x02
 #define MT_INPUTMODE_TOUCHPAD		0x03
 
 #define MT_BUTTONTYPE_CLICKPAD		0
 
+#define MS_TYPE_COVER_FEATURE_REPORT_USAGE	0xff050086
+
 enum latency_mode {
 	HID_LATENCY_NORMAL = 0,
 	HID_LATENCY_HIGH = 1,
@@ -168,6 +175,8 @@ struct mt_device {
 
 	struct list_head applications;
 	struct list_head reports;
+
+	struct notifier_block pm_notifier;
 };
 
 static void mt_post_parse_default_settings(struct mt_device *td,
@@ -212,6 +221,7 @@ static void mt_post_parse(struct mt_device *td, struct mt_application *app);
 #define MT_CLS_GOOGLE				0x0111
 #define MT_CLS_RAZER_BLADE_STEALTH		0x0112
 #define MT_CLS_SMART_TECH			0x0113
+#define MT_CLS_WIN_8_MS_SURFACE_TYPE_COVER	0x0114
 
 #define MT_DEFAULT_MAXCONTACT	10
 #define MT_MAX_MAXCONTACT	250
@@ -396,6 +406,16 @@ static const struct mt_class mt_classes[] = {
 			MT_QUIRK_CONTACT_CNT_ACCURATE |
 			MT_QUIRK_SEPARATE_APP_REPORT,
 	},
+	{ .name = MT_CLS_WIN_8_MS_SURFACE_TYPE_COVER,
+		.quirks = MT_QUIRK_HAS_TYPE_COVER_BACKLIGHT |
+			MT_QUIRK_ALWAYS_VALID |
+			MT_QUIRK_IGNORE_DUPLICATES |
+			MT_QUIRK_HOVERING |
+			MT_QUIRK_CONTACT_CNT_ACCURATE |
+			MT_QUIRK_STICKY_FINGERS |
+			MT_QUIRK_WIN8_PTP_BUTTONS,
+		.export_all_inputs = true
+	},
 	{ }
 };
 
@@ -1706,6 +1726,69 @@ static void mt_expired_timeout(struct timer_list *t)
 	clear_bit_unlock(MT_IO_FLAGS_RUNNING, &td->mt_io_flags);
 }
 
+static void get_type_cover_backlight_field(struct hid_device *hdev,
+					   struct hid_field **field)
+{
+	struct hid_report_enum *rep_enum;
+	struct hid_report *rep;
+	struct hid_field *cur_field;
+	int i, j;
+
+	rep_enum = &hdev->report_enum[HID_FEATURE_REPORT];
+	list_for_each_entry(rep, &rep_enum->report_list, list) {
+		for (i = 0; i < rep->maxfield; i++) {
+			cur_field = rep->field[i];
+
+			for (j = 0; j < cur_field->maxusage; j++) {
+				if (cur_field->usage[j].hid
+				    == MS_TYPE_COVER_FEATURE_REPORT_USAGE) {
+					*field = cur_field;
+					return;
+				}
+			}
+		}
+	}
+}
+
+static void update_keyboard_backlight(struct hid_device *hdev, bool enabled)
+{
+	struct usb_device *udev = hid_to_usb_dev(hdev);
+	struct hid_field *field = NULL;
+
+	/* Wake up the device in case it's already suspended */
+	pm_runtime_get_sync(&udev->dev);
+
+	get_type_cover_backlight_field(hdev, &field);
+	if (!field) {
+		hid_err(hdev, "couldn't find backlight field\n");
+		goto out;
+	}
+
+	field->value[field->index] = enabled ? 0x01ff00ff : 0x00ff00ff;
+	hid_hw_request(hdev, field->report, HID_REQ_SET_REPORT);
+
+out:
+	pm_runtime_put_sync(&udev->dev);
+}
+
+static int mt_pm_notifier(struct notifier_block *notifier,
+			  unsigned long pm_event,
+			  void *unused)
+{
+	struct mt_device *td =
+		container_of(notifier, struct mt_device, pm_notifier);
+	struct hid_device *hdev = td->hdev;
+
+	if (td->mtclass.quirks & MT_QUIRK_HAS_TYPE_COVER_BACKLIGHT) {
+		if (pm_event == PM_SUSPEND_PREPARE)
+			update_keyboard_backlight(hdev, 0);
+		else if (pm_event == PM_POST_SUSPEND)
+			update_keyboard_backlight(hdev, 1);
+	}
+
+	return NOTIFY_DONE;
+}
+
 static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
 {
 	int ret, i;
@@ -1729,6 +1812,9 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
 	td->inputmode_value = MT_INPUTMODE_TOUCHSCREEN;
 	hid_set_drvdata(hdev, td);
 
+	td->pm_notifier.notifier_call = mt_pm_notifier;
+	register_pm_notifier(&td->pm_notifier);
+
 	INIT_LIST_HEAD(&td->applications);
 	INIT_LIST_HEAD(&td->reports);
 
@@ -1758,15 +1844,19 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
 	timer_setup(&td->release_timer, mt_expired_timeout, 0);
 
 	ret = hid_parse(hdev);
-	if (ret != 0)
+	if (ret != 0) {
+		unregister_pm_notifier(&td->pm_notifier);
 		return ret;
+	}
 
 	if (mtclass->quirks & MT_QUIRK_FIX_CONST_CONTACT_ID)
 		mt_fix_const_fields(hdev, HID_DG_CONTACTID);
 
 	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
-	if (ret)
+	if (ret) {
+		unregister_pm_notifier(&td->pm_notifier);
 		return ret;
+	}
 
 	ret = sysfs_create_group(&hdev->dev.kobj, &mt_attribute_group);
 	if (ret)
@@ -1818,6 +1908,7 @@ static void mt_remove(struct hid_device *hdev)
 {
 	struct mt_device *td = hid_get_drvdata(hdev);
 
+	unregister_pm_notifier(&td->pm_notifier);
 	del_timer_sync(&td->release_timer);
 
 	sysfs_remove_group(&hdev->dev.kobj, &mt_attribute_group);
@@ -2191,6 +2282,11 @@ static const struct hid_device_id mt_devices[] = {
 		MT_USB_DEVICE(USB_VENDOR_ID_XIROKU,
 			USB_DEVICE_ID_XIROKU_CSR2) },
 
+	/* Microsoft Surface type cover */
+	{ .driver_data = MT_CLS_WIN_8_MS_SURFACE_TYPE_COVER,
+		HID_DEVICE(HID_BUS_ANY, HID_GROUP_ANY,
+			USB_VENDOR_ID_MICROSOFT, 0x09c0) },
+
 	/* Google MT devices */
 	{ .driver_data = MT_CLS_GOOGLE,
 		HID_DEVICE(HID_BUS_ANY, HID_GROUP_ANY, USB_VENDOR_ID_GOOGLE,
-- 
2.38.1

From 219e89d9c3d57bc998ed6aafde09c96105a80dad Mon Sep 17 00:00:00 2001
From: PJungkamp <p.jungkamp@gmail.com>
Date: Fri, 25 Feb 2022 12:04:25 +0100
Subject: [PATCH] hid/multitouch: Add support for surface pro type cover tablet
 switch

The Surface Pro Type Cover has several non standard HID usages in it's
hid report descriptor.
I noticed that, upon folding the typecover back, a vendor specific range
of 4 32 bit integer hid usages is transmitted.
Only the first byte of the message seems to convey reliable information
about the keyboard state.

0x22 => Normal (keys enabled)
0x33 => Folded back (keys disabled)
0x53 => Rotated left/right side up (keys disabled)
0x13 => Cover closed (keys disabled)
0x43 => Folded back and Tablet upside down (keys disabled)
This list may not be exhaustive.

The tablet mode switch will be disabled for a value of 0x22 and enabled
on any other value.

Patchset: surface-typecover
---
 drivers/hid/hid-multitouch.c | 148 +++++++++++++++++++++++++++++------
 1 file changed, 122 insertions(+), 26 deletions(-)

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 458537bf4a8e..3d7d002a662f 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -76,6 +76,7 @@ MODULE_LICENSE("GPL");
 #define MT_QUIRK_FORCE_MULTI_INPUT	BIT(20)
 #define MT_QUIRK_DISABLE_WAKEUP		BIT(21)
 #define MT_QUIRK_HAS_TYPE_COVER_BACKLIGHT	BIT(22)
+#define MT_QUIRK_HAS_TYPE_COVER_TABLET_MODE_SWITCH	BIT(23)
 
 #define MT_INPUTMODE_TOUCHSCREEN	0x02
 #define MT_INPUTMODE_TOUCHPAD		0x03
@@ -83,6 +84,8 @@ MODULE_LICENSE("GPL");
 #define MT_BUTTONTYPE_CLICKPAD		0
 
 #define MS_TYPE_COVER_FEATURE_REPORT_USAGE	0xff050086
+#define MS_TYPE_COVER_TABLET_MODE_SWITCH_USAGE	0xff050072
+#define MS_TYPE_COVER_APPLICATION	0xff050050
 
 enum latency_mode {
 	HID_LATENCY_NORMAL = 0,
@@ -408,6 +411,7 @@ static const struct mt_class mt_classes[] = {
 	},
 	{ .name = MT_CLS_WIN_8_MS_SURFACE_TYPE_COVER,
 		.quirks = MT_QUIRK_HAS_TYPE_COVER_BACKLIGHT |
+			MT_QUIRK_HAS_TYPE_COVER_TABLET_MODE_SWITCH |
 			MT_QUIRK_ALWAYS_VALID |
 			MT_QUIRK_IGNORE_DUPLICATES |
 			MT_QUIRK_HOVERING |
@@ -1368,6 +1372,9 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi,
 	    field->application != HID_CP_CONSUMER_CONTROL &&
 	    field->application != HID_GD_WIRELESS_RADIO_CTLS &&
 	    field->application != HID_GD_SYSTEM_MULTIAXIS &&
+	    !(field->application == MS_TYPE_COVER_APPLICATION &&
+	      application->quirks & MT_QUIRK_HAS_TYPE_COVER_TABLET_MODE_SWITCH &&
+	      usage->hid == MS_TYPE_COVER_TABLET_MODE_SWITCH_USAGE) &&
 	    !(field->application == HID_VD_ASUS_CUSTOM_MEDIA_KEYS &&
 	      application->quirks & MT_QUIRK_ASUS_CUSTOM_UP))
 		return -1;
@@ -1395,6 +1402,21 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi,
 		return 1;
 	}
 
+	/*
+	 * The Microsoft Surface Pro Typecover has a non-standard HID
+	 * tablet mode switch on a vendor specific usage page with vendor
+	 * specific usage.
+	 */
+	if (field->application == MS_TYPE_COVER_APPLICATION &&
+	    application->quirks & MT_QUIRK_HAS_TYPE_COVER_TABLET_MODE_SWITCH &&
+	    usage->hid == MS_TYPE_COVER_TABLET_MODE_SWITCH_USAGE) {
+		usage->type = EV_SW;
+		usage->code = SW_TABLET_MODE;
+		*max = SW_MAX;
+		*bit = hi->input->swbit;
+		return 1;
+	}
+
 	if (rdata->is_mt_collection)
 		return mt_touch_input_mapping(hdev, hi, field, usage, bit, max,
 					      application);
@@ -1416,6 +1438,7 @@ static int mt_input_mapped(struct hid_device *hdev, struct hid_input *hi,
 {
 	struct mt_device *td = hid_get_drvdata(hdev);
 	struct mt_report_data *rdata;
+	struct input_dev *input;
 
 	rdata = mt_find_report_data(td, field->report);
 	if (rdata && rdata->is_mt_collection) {
@@ -1423,6 +1446,19 @@ static int mt_input_mapped(struct hid_device *hdev, struct hid_input *hi,
 		return -1;
 	}
 
+	/*
+	 * We own an input device which acts as a tablet mode switch for
+	 * the Surface Pro Typecover.
+	 */
+	if (field->application == MS_TYPE_COVER_APPLICATION &&
+	    rdata->application->quirks & MT_QUIRK_HAS_TYPE_COVER_TABLET_MODE_SWITCH &&
+	    usage->hid == MS_TYPE_COVER_TABLET_MODE_SWITCH_USAGE) {
+		input = hi->input;
+		input_set_capability(input, EV_SW, SW_TABLET_MODE);
+		input_report_switch(input, SW_TABLET_MODE, 0);
+		return -1;
+	}
+
 	/* let hid-core decide for the others */
 	return 0;
 }
@@ -1432,11 +1468,21 @@ static int mt_event(struct hid_device *hid, struct hid_field *field,
 {
 	struct mt_device *td = hid_get_drvdata(hid);
 	struct mt_report_data *rdata;
+	struct input_dev *input;
 
 	rdata = mt_find_report_data(td, field->report);
 	if (rdata && rdata->is_mt_collection)
 		return mt_touch_event(hid, field, usage, value);
 
+	if (field->application == MS_TYPE_COVER_APPLICATION &&
+	    rdata->application->quirks & MT_QUIRK_HAS_TYPE_COVER_TABLET_MODE_SWITCH &&
+	    usage->hid == MS_TYPE_COVER_TABLET_MODE_SWITCH_USAGE) {
+		input = field->hidinput->input;
+		input_report_switch(input, SW_TABLET_MODE, (value & 0xFF) != 0x22);
+		input_sync(input);
+		return 1;
+	}
+
 	return 0;
 }
 
@@ -1589,6 +1635,42 @@ static void mt_post_parse(struct mt_device *td, struct mt_application *app)
 		app->quirks &= ~MT_QUIRK_CONTACT_CNT_ACCURATE;
 }
 
+static int get_type_cover_field(struct hid_report_enum *rep_enum,
+				struct hid_field **field, int usage)
+{
+	struct hid_report *rep;
+	struct hid_field *cur_field;
+	int i, j;
+
+	list_for_each_entry(rep, &rep_enum->report_list, list) {
+		for (i = 0; i < rep->maxfield; i++) {
+			cur_field = rep->field[i];
+			if (cur_field->application != MS_TYPE_COVER_APPLICATION)
+				continue;
+			for (j = 0; j < cur_field->maxusage; j++) {
+				if (cur_field->usage[j].hid == usage) {
+					*field = cur_field;
+					return true;
+				}
+			}
+		}
+	}
+	return false;
+}
+
+static void request_type_cover_tablet_mode_switch(struct hid_device *hdev)
+{
+	struct hid_field *field;
+
+	if (get_type_cover_field(&hdev->report_enum[HID_INPUT_REPORT],
+				 &field,
+				 MS_TYPE_COVER_TABLET_MODE_SWITCH_USAGE)) {
+		hid_hw_request(hdev, field->report, HID_REQ_GET_REPORT);
+	} else {
+		hid_err(hdev, "couldn't find tablet mode field\n");
+	}
+}
+
 static int mt_input_configured(struct hid_device *hdev, struct hid_input *hi)
 {
 	struct mt_device *td = hid_get_drvdata(hdev);
@@ -1638,6 +1720,13 @@ static int mt_input_configured(struct hid_device *hdev, struct hid_input *hi)
 		/* force BTN_STYLUS to allow tablet matching in udev */
 		__set_bit(BTN_STYLUS, hi->input->keybit);
 		break;
+	case MS_TYPE_COVER_APPLICATION:
+		if (td->mtclass.quirks & MT_QUIRK_HAS_TYPE_COVER_TABLET_MODE_SWITCH) {
+			suffix = "Tablet Mode Switch";
+			request_type_cover_tablet_mode_switch(hdev);
+			break;
+		}
+		fallthrough;
 	default:
 		suffix = "UNKNOWN";
 		break;
@@ -1726,30 +1815,6 @@ static void mt_expired_timeout(struct timer_list *t)
 	clear_bit_unlock(MT_IO_FLAGS_RUNNING, &td->mt_io_flags);
 }
 
-static void get_type_cover_backlight_field(struct hid_device *hdev,
-					   struct hid_field **field)
-{
-	struct hid_report_enum *rep_enum;
-	struct hid_report *rep;
-	struct hid_field *cur_field;
-	int i, j;
-
-	rep_enum = &hdev->report_enum[HID_FEATURE_REPORT];
-	list_for_each_entry(rep, &rep_enum->report_list, list) {
-		for (i = 0; i < rep->maxfield; i++) {
-			cur_field = rep->field[i];
-
-			for (j = 0; j < cur_field->maxusage; j++) {
-				if (cur_field->usage[j].hid
-				    == MS_TYPE_COVER_FEATURE_REPORT_USAGE) {
-					*field = cur_field;
-					return;
-				}
-			}
-		}
-	}
-}
-
 static void update_keyboard_backlight(struct hid_device *hdev, bool enabled)
 {
 	struct usb_device *udev = hid_to_usb_dev(hdev);
@@ -1758,8 +1823,9 @@ static void update_keyboard_backlight(struct hid_device *hdev, bool enabled)
 	/* Wake up the device in case it's already suspended */
 	pm_runtime_get_sync(&udev->dev);
 
-	get_type_cover_backlight_field(hdev, &field);
-	if (!field) {
+	if (!get_type_cover_field(&hdev->report_enum[HID_FEATURE_REPORT],
+				  &field,
+				  MS_TYPE_COVER_FEATURE_REPORT_USAGE)) {
 		hid_err(hdev, "couldn't find backlight field\n");
 		goto out;
 	}
@@ -1885,13 +1951,24 @@ static int mt_suspend(struct hid_device *hdev, pm_message_t state)
 
 static int mt_reset_resume(struct hid_device *hdev)
 {
+	struct mt_device *td = hid_get_drvdata(hdev);
+
 	mt_release_contacts(hdev);
 	mt_set_modes(hdev, HID_LATENCY_NORMAL, true, true);
+
+	/* Request an update on the typecover folding state on resume
+	 * after reset.
+	 */
+	if (td->mtclass.quirks & MT_QUIRK_HAS_TYPE_COVER_TABLET_MODE_SWITCH)
+		request_type_cover_tablet_mode_switch(hdev);
+
 	return 0;
 }
 
 static int mt_resume(struct hid_device *hdev)
 {
+	struct mt_device *td = hid_get_drvdata(hdev);
+
 	/* Some Elan legacy devices require SET_IDLE to be set on resume.
 	 * It should be safe to send it to other devices too.
 	 * Tested on 3M, Stantum, Cypress, Zytronic, eGalax, and Elan panels. */
@@ -1900,6 +1977,10 @@ static int mt_resume(struct hid_device *hdev)
 
 	mt_set_modes(hdev, HID_LATENCY_NORMAL, true, true);
 
+	/* Request an update on the typecover folding state on resume. */
+	if (td->mtclass.quirks & MT_QUIRK_HAS_TYPE_COVER_TABLET_MODE_SWITCH)
+		request_type_cover_tablet_mode_switch(hdev);
+
 	return 0;
 }
 #endif
@@ -1907,6 +1988,21 @@ static int mt_resume(struct hid_device *hdev)
 static void mt_remove(struct hid_device *hdev)
 {
 	struct mt_device *td = hid_get_drvdata(hdev);
+	struct hid_field *field;
+	struct input_dev *input;
+
+	/* Reset tablet mode switch on disconnect. */
+	if (td->mtclass.quirks & MT_QUIRK_HAS_TYPE_COVER_TABLET_MODE_SWITCH) {
+		if (get_type_cover_field(&hdev->report_enum[HID_INPUT_REPORT],
+					 &field,
+					 MS_TYPE_COVER_TABLET_MODE_SWITCH_USAGE)) {
+			input = field->hidinput->input;
+			input_report_switch(input, SW_TABLET_MODE, 0);
+			input_sync(input);
+		} else {
+			hid_err(hdev, "couldn't find tablet mode field\n");
+		}
+	}
 
 	unregister_pm_notifier(&td->pm_notifier);
 	del_timer_sync(&td->release_timer);
-- 
2.38.1