[PATCH v3 0/2] platform/x86: Add driver for Yoga Tablet mode switch

[PATCH v3 0/2] platform/x86: Add driver for Yoga Tablet mode switch

[Andrew Kallmeyer]

This driver maps the Lenovo Yoga tablet mode switch to a SW_TABLET_MODE input
device. This will make the tablet status available to desktop environments.

This patch series is the result of the discussion at
https://lore.kernel.org/r/CAG4kvq9US=-NjyXFMzJYu2zCJryJWtOc7FGZbrewpgCDjdAkbg@mail.gmail.com/

I decided to follow-up on the patch Gergo wrote and respond to the review
comments to get it merged and available for everyone.

Gergo and I have tested this on the Yoga 7 14ARB7, and the Yoga 7 14AIL7
respectively. Additionally, according to reports at
https://github.com/lukas-w/yoga-usage-mode, which uses the same WMI devices,
this driver should work with:
Yoga C940, Ideapad flex 14API, Yoga 9 14IAP7, Yoga 7 14ARB7, etc.

v1: https://lore.kernel.org/r/20230310041726.217447-1-kallmeyeras@gmail.com/
v2: https://lore.kernel.org/r/20230323025200.5462-1-kallmeyeras@gmail.com/
The diff since v2 is as follows:

--- a/drivers/platform/x86/lenovo-ymc.c
+++ b/drivers/platform/x86/lenovo-ymc.c
@@ -21,8 +21,8 @@
 #define LENOVO_YMC_QUERY_METHOD 0x01
 
 static bool ec_trigger __read_mostly;
-module_param(ec_trigger, bool, 0644);
-MODULE_PARM_DESC(ec_trigger, "Enable EC triggering to emit YMC events");
+module_param(ec_trigger, bool, 0444);
+MODULE_PARM_DESC(ec_trigger, "Enable EC triggering work-around to force emitting tablet mode events");
 
 static const struct dmi_system_id ec_trigger_quirk_dmi_table[] = {
 	{
@@ -43,8 +43,7 @@ struct lenovo_ymc_private {
 static void lenovo_ymc_trigger_ec(struct wmi_device *wdev, struct lenovo_ymc_private *priv)
 {
 	int err;
-
-	if (!ec_trigger || !priv || !priv->ec_acpi_dev)
+	if (!priv->ec_acpi_dev)
 		return;
 	err = write_ec_cmd(priv->ec_acpi_dev->handle, VPCCMD_W_YMC, 1);
 	if (err)
@@ -103,11 +102,7 @@ static void lenovo_ymc_notify(struct wmi_device *wdev, union acpi_object *data)
 	lenovo_ymc_trigger_ec(wdev, priv);
 }
 
-static void lenovo_ymc_remove(struct wmi_device *wdev)
-{
-	struct lenovo_ymc_private *priv = dev_get_drvdata(&wdev->dev);
-	acpi_dev_put(priv->ec_acpi_dev);
-}
+static void acpi_dev_put_helper(void *p) { acpi_dev_put(p); }
 
 static int lenovo_ymc_probe(struct wmi_device *wdev, const void *ctx)
 {
@@ -124,10 +119,18 @@ static int lenovo_ymc_probe(struct wmi_device *wdev, const void *ctx)
 	if (ec_trigger) {
 		pr_debug("Lenovo YMC enable EC triggering.\n");
 		priv->ec_acpi_dev = acpi_dev_get_first_match_dev("VPC2004", NULL, -1);
+
 		if (!priv->ec_acpi_dev) {
 			dev_err(&wdev->dev, "Could not find EC ACPI device.\n");
 			return -ENODEV;
 		}
+		err = devm_add_action_or_reset(&wdev->dev,
+				acpi_dev_put_helper, priv->ec_acpi_dev);
+		if (err) {
+			dev_err(&wdev->dev,
+				"Could not clean up EC ACPI device: %d\n", err);
+			return err;
+		}
 	}
 
 	input_dev = devm_input_allocate_device(&wdev->dev);
@@ -138,9 +141,6 @@ static int lenovo_ymc_probe(struct wmi_device *wdev, const void *ctx)
 	input_dev->phys = LENOVO_YMC_EVENT_GUID "/input0";
 	input_dev->id.bustype = BUS_HOST;
 	input_dev->dev.parent = &wdev->dev;
-
-	input_set_capability(input_dev, EV_SW, SW_TABLET_MODE);
-
 	err = sparse_keymap_setup(input_dev, lenovo_ymc_keymap, NULL);
 	if (err) {
 		dev_err(&wdev->dev,
@@ -177,7 +177,6 @@ static struct wmi_driver lenovo_ymc_driver = {
 	.id_table = lenovo_ymc_wmi_id_table,
 	.probe = lenovo_ymc_probe,
 	.notify = lenovo_ymc_notify,
-	.remove = lenovo_ymc_remove,
 };
 
 module_wmi_driver(lenovo_ymc_driver);

Andrew Kallmeyer (1):
  platform/x86: Move ideapad ACPI helpers to a new header

Gergo Koteles (1):
  platform/x86: Add driver for Yoga Tablet Mode switch

 drivers/platform/x86/Kconfig          |  10 ++
 drivers/platform/x86/Makefile         |   1 +
 drivers/platform/x86/ideapad-laptop.c | 135 +------------------
 drivers/platform/x86/ideapad-laptop.h | 152 +++++++++++++++++++++
 drivers/platform/x86/lenovo-ymc.c     | 185 ++++++++++++++++++++++++++
 5 files changed, 349 insertions(+), 134 deletions(-)
 create mode 100644 drivers/platform/x86/ideapad-laptop.h
 create mode 100644 drivers/platform/x86/lenovo-ymc.c

-- 
2.40.0

[PATCH v3 1/2] platform/x86: Move ideapad ACPI helpers to a new header

[Andrew Kallmeyer]

These functions will be used by a driver written by Gergo Koteles to
detect the tablet mode switch in Lenovo Yoga laptops. These changes were
discussed in review of that patch.

This is the minimal set of functions needed in that driver, there are
several more small functions left in the ACPI Helpers section in
ideapad-laptop.c. The only change is the functions are now marked inline
as requested in the review comments.

Signed-off-by: Andrew Kallmeyer <kallmeyeras@gmail.com>
Link: https://lore.kernel.org/r/20221004214332.35934-1-soyer@irl.hu/
---
 drivers/platform/x86/ideapad-laptop.c | 135 +----------------------
 drivers/platform/x86/ideapad-laptop.h | 151 ++++++++++++++++++++++++++
 2 files changed, 152 insertions(+), 134 deletions(-)
 create mode 100644 drivers/platform/x86/ideapad-laptop.h

diff --git a/drivers/platform/x86/ideapad-laptop.c b/drivers/platform/x86/ideapad-laptop.c
index 0eb5bfdd8..55f56697e 100644
--- a/drivers/platform/x86/ideapad-laptop.c
+++ b/drivers/platform/x86/ideapad-laptop.c
@@ -20,7 +20,6 @@
 #include <linux/init.h>
 #include <linux/input.h>
 #include <linux/input/sparse-keymap.h>
-#include <linux/jiffies.h>
 #include <linux/kernel.h>
 #include <linux/leds.h>
 #include <linux/module.h>
@@ -31,6 +30,7 @@
 #include <linux/sysfs.h>
 #include <linux/types.h>
 #include <linux/wmi.h>
+#include "ideapad-laptop.h"
 
 #include <acpi/video.h>
 
@@ -85,33 +85,6 @@ enum {
 	SALS_FNLOCK_OFF       = 0xf,
 };
 
-enum {
-	VPCCMD_R_VPC1 = 0x10,
-	VPCCMD_R_BL_MAX,
-	VPCCMD_R_BL,
-	VPCCMD_W_BL,
-	VPCCMD_R_WIFI,
-	VPCCMD_W_WIFI,
-	VPCCMD_R_BT,
-	VPCCMD_W_BT,
-	VPCCMD_R_BL_POWER,
-	VPCCMD_R_NOVO,
-	VPCCMD_R_VPC2,
-	VPCCMD_R_TOUCHPAD,
-	VPCCMD_W_TOUCHPAD,
-	VPCCMD_R_CAMERA,
-	VPCCMD_W_CAMERA,
-	VPCCMD_R_3G,
-	VPCCMD_W_3G,
-	VPCCMD_R_ODD, /* 0x21 */
-	VPCCMD_W_FAN,
-	VPCCMD_R_RF,
-	VPCCMD_W_RF,
-	VPCCMD_R_FAN = 0x2B,
-	VPCCMD_R_SPECIAL_BUTTONS = 0x31,
-	VPCCMD_W_BL_POWER = 0x33,
-};
-
 struct ideapad_dytc_priv {
 	enum platform_profile_option current_profile;
 	struct platform_profile_handler pprof;
@@ -227,7 +200,6 @@ static void ideapad_shared_exit(struct ideapad_private *priv)
 /*
  * ACPI Helpers
  */
-#define IDEAPAD_EC_TIMEOUT 200 /* in ms */
 
 static int eval_int(acpi_handle handle, const char *name, unsigned long *res)
 {
@@ -270,116 +242,11 @@ static int exec_sals(acpi_handle handle, unsigned long arg)
 	return exec_simple_method(handle, "SALS", arg);
 }
 
-static int eval_int_with_arg(acpi_handle handle, const char *name, unsigned long arg, unsigned long *res)
-{
-	struct acpi_object_list params;
-	unsigned long long result;
-	union acpi_object in_obj;
-	acpi_status status;
-
-	params.count = 1;
-	params.pointer = &in_obj;
-	in_obj.type = ACPI_TYPE_INTEGER;
-	in_obj.integer.value = arg;
-
-	status = acpi_evaluate_integer(handle, (char *)name, &params, &result);
-	if (ACPI_FAILURE(status))
-		return -EIO;
-
-	if (res)
-		*res = result;
-
-	return 0;
-}
-
 static int eval_dytc(acpi_handle handle, unsigned long cmd, unsigned long *res)
 {
 	return eval_int_with_arg(handle, "DYTC", cmd, res);
 }
 
-static int eval_vpcr(acpi_handle handle, unsigned long cmd, unsigned long *res)
-{
-	return eval_int_with_arg(handle, "VPCR", cmd, res);
-}
-
-static int eval_vpcw(acpi_handle handle, unsigned long cmd, unsigned long data)
-{
-	struct acpi_object_list params;
-	union acpi_object in_obj[2];
-	acpi_status status;
-
-	params.count = 2;
-	params.pointer = in_obj;
-	in_obj[0].type = ACPI_TYPE_INTEGER;
-	in_obj[0].integer.value = cmd;
-	in_obj[1].type = ACPI_TYPE_INTEGER;
-	in_obj[1].integer.value = data;
-
-	status = acpi_evaluate_object(handle, "VPCW", &params, NULL);
-	if (ACPI_FAILURE(status))
-		return -EIO;
-
-	return 0;
-}
-
-static int read_ec_data(acpi_handle handle, unsigned long cmd, unsigned long *data)
-{
-	unsigned long end_jiffies, val;
-	int err;
-
-	err = eval_vpcw(handle, 1, cmd);
-	if (err)
-		return err;
-
-	end_jiffies = jiffies + msecs_to_jiffies(IDEAPAD_EC_TIMEOUT) + 1;
-
-	while (time_before(jiffies, end_jiffies)) {
-		schedule();
-
-		err = eval_vpcr(handle, 1, &val);
-		if (err)
-			return err;
-
-		if (val == 0)
-			return eval_vpcr(handle, 0, data);
-	}
-
-	acpi_handle_err(handle, "timeout in %s\n", __func__);
-
-	return -ETIMEDOUT;
-}
-
-static int write_ec_cmd(acpi_handle handle, unsigned long cmd, unsigned long data)
-{
-	unsigned long end_jiffies, val;
-	int err;
-
-	err = eval_vpcw(handle, 0, data);
-	if (err)
-		return err;
-
-	err = eval_vpcw(handle, 1, cmd);
-	if (err)
-		return err;
-
-	end_jiffies = jiffies + msecs_to_jiffies(IDEAPAD_EC_TIMEOUT) + 1;
-
-	while (time_before(jiffies, end_jiffies)) {
-		schedule();
-
-		err = eval_vpcr(handle, 1, &val);
-		if (err)
-			return err;
-
-		if (val == 0)
-			return 0;
-	}
-
-	acpi_handle_err(handle, "timeout in %s\n", __func__);
-
-	return -ETIMEDOUT;
-}
-
 /*
  * debugfs
  */
diff --git a/drivers/platform/x86/ideapad-laptop.h b/drivers/platform/x86/ideapad-laptop.h
new file mode 100644
index 000000000..7dd8ce027
--- /dev/null
+++ b/drivers/platform/x86/ideapad-laptop.h
@@ -0,0 +1,151 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  ideapad-laptop.h - Lenovo IdeaPad ACPI Extras
+ *
+ *  Copyright © 2010 Intel Corporation
+ *  Copyright © 2010 David Woodhouse <dwmw2@infradead.org>
+ */
+
+#ifndef _IDEAPAD_LAPTOP_H_
+#define _IDEAPAD_LAPTOP_H_
+
+#include <linux/acpi.h>
+#include <linux/jiffies.h>
+#include <linux/errno.h>
+
+enum {
+	VPCCMD_R_VPC1 = 0x10,
+	VPCCMD_R_BL_MAX,
+	VPCCMD_R_BL,
+	VPCCMD_W_BL,
+	VPCCMD_R_WIFI,
+	VPCCMD_W_WIFI,
+	VPCCMD_R_BT,
+	VPCCMD_W_BT,
+	VPCCMD_R_BL_POWER,
+	VPCCMD_R_NOVO,
+	VPCCMD_R_VPC2,
+	VPCCMD_R_TOUCHPAD,
+	VPCCMD_W_TOUCHPAD,
+	VPCCMD_R_CAMERA,
+	VPCCMD_W_CAMERA,
+	VPCCMD_R_3G,
+	VPCCMD_W_3G,
+	VPCCMD_R_ODD, /* 0x21 */
+	VPCCMD_W_FAN,
+	VPCCMD_R_RF,
+	VPCCMD_W_RF,
+	VPCCMD_R_FAN = 0x2B,
+	VPCCMD_R_SPECIAL_BUTTONS = 0x31,
+	VPCCMD_W_BL_POWER = 0x33,
+};
+
+static inline int eval_int_with_arg(acpi_handle handle, const char *name, unsigned long arg, unsigned long *res)
+{
+	struct acpi_object_list params;
+	unsigned long long result;
+	union acpi_object in_obj;
+	acpi_status status;
+
+	params.count = 1;
+	params.pointer = &in_obj;
+	in_obj.type = ACPI_TYPE_INTEGER;
+	in_obj.integer.value = arg;
+
+	status = acpi_evaluate_integer(handle, (char *)name, &params, &result);
+	if (ACPI_FAILURE(status))
+		return -EIO;
+
+	if (res)
+		*res = result;
+
+	return 0;
+}
+
+static inline int eval_vpcr(acpi_handle handle, unsigned long cmd, unsigned long *res)
+{
+	return eval_int_with_arg(handle, "VPCR", cmd, res);
+}
+
+static inline int eval_vpcw(acpi_handle handle, unsigned long cmd, unsigned long data)
+{
+	struct acpi_object_list params;
+	union acpi_object in_obj[2];
+	acpi_status status;
+
+	params.count = 2;
+	params.pointer = in_obj;
+	in_obj[0].type = ACPI_TYPE_INTEGER;
+	in_obj[0].integer.value = cmd;
+	in_obj[1].type = ACPI_TYPE_INTEGER;
+	in_obj[1].integer.value = data;
+
+	status = acpi_evaluate_object(handle, "VPCW", &params, NULL);
+	if (ACPI_FAILURE(status))
+		return -EIO;
+
+	return 0;
+}
+
+#define IDEAPAD_EC_TIMEOUT 200 /* in ms */
+
+static inline int read_ec_data(acpi_handle handle, unsigned long cmd, unsigned long *data)
+{
+	unsigned long end_jiffies, val;
+	int err;
+
+	err = eval_vpcw(handle, 1, cmd);
+	if (err)
+		return err;
+
+	end_jiffies = jiffies + msecs_to_jiffies(IDEAPAD_EC_TIMEOUT) + 1;
+
+	while (time_before(jiffies, end_jiffies)) {
+		schedule();
+
+		err = eval_vpcr(handle, 1, &val);
+		if (err)
+			return err;
+
+		if (val == 0)
+			return eval_vpcr(handle, 0, data);
+	}
+
+	acpi_handle_err(handle, "timeout in %s\n", __func__);
+
+	return -ETIMEDOUT;
+}
+
+static inline int write_ec_cmd(acpi_handle handle, unsigned long cmd, unsigned long data)
+{
+	unsigned long end_jiffies, val;
+	int err;
+
+	err = eval_vpcw(handle, 0, data);
+	if (err)
+		return err;
+
+	err = eval_vpcw(handle, 1, cmd);
+	if (err)
+		return err;
+
+	end_jiffies = jiffies + msecs_to_jiffies(IDEAPAD_EC_TIMEOUT) + 1;
+
+	while (time_before(jiffies, end_jiffies)) {
+		schedule();
+
+		err = eval_vpcr(handle, 1, &val);
+		if (err)
+			return err;
+
+		if (val == 0)
+			return 0;
+	}
+
+	acpi_handle_err(handle, "timeout in %s\n", __func__);
+
+	return -ETIMEDOUT;
+}
+
+#undef IDEAPAD_EC_TIMEOUT
+#endif /* !_IDEAPAD_LAPTOP_H_ */
-- 
2.40.0

[PATCH v3 2/2] platform/x86: Add driver for Yoga Tablet Mode switch

[Andrew Kallmeyer]

From: Gergo Koteles <soyer@irl.hu>

This WMI driver for the tablet mode control switch for Lenovo Yoga
notebooks was originally written by Gergo Koteles. The mode is mapped to
a SW_TABLET_MODE switch capable input device.

Andrew followed the suggestions that were posted in reply to Gergo's RFC
patch, and on the v1 & v2 versions of this patch to follow-up and get it
merged.

Changes from Gergo's RFC:

 - Refactored obtaining a reference to the EC ACPI device needed for the
   quirk implementation as suggested by Hans de Goede
 - Applied small fixes and switched to always registering handles with
   the driver for automatic cleanup as suggested by Barnabás Pőcze.
 - Merged the lenovo_ymc_trigger_ec function with the
   ideapad_trigger_ymc_next_read function since it was no longer
   external.
 - Added the word "Tablet" to the driver description to hopefully make
   it more clear.
 - Fixed the LENOVO_YMC_QUERY_METHOD ID and the name string for the EC
   APCI device trigged for the quirk
 - Triggered the input event on probe so that the initial tablet mode
   state when the driver is loaded is reported to userspace as suggested
   by Armin Wolf.
 - Restricted the permissions of the ec_trigger parameter as suggested
   by Armin Wolf. Also updated the description.

We have tested this on the Yoga 7 14AIL7 for the non-quirk path and on
the Yoga 7 14ARB7 which has the firmware bug that requires triggering
the embedded controller to send the mode change events. This workaround
is also used by the Windows drivers.

According to reports at https://github.com/lukas-w/yoga-usage-mode,
which uses the same WMI devices, the following models should also work:
Yoga C940, Ideapad flex 14API, Yoga 9 14IAP7, Yoga 7 14ARB7, etc.

Signed-off-by: Gergo Koteles <soyer@irl.hu>
Co-developed-by: Andrew Kallmeyer <kallmeyeras@gmail.com>
Signed-off-by: Andrew Kallmeyer <kallmeyeras@gmail.com>
Link: https://lore.kernel.org/r/20221004214332.35934-1-soyer@irl.hu/
Link: https://lore.kernel.org/r/20230310041726.217447-1-kallmeyeras@gmail.com/
Link: https://lore.kernel.org/r/20230323025200.5462-1-kallmeyeras@gmail.com/
---
 drivers/platform/x86/Kconfig          |  10 ++
 drivers/platform/x86/Makefile         |   1 +
 drivers/platform/x86/ideapad-laptop.h |   1 +
 drivers/platform/x86/lenovo-ymc.c     | 186 ++++++++++++++++++++++++++
 4 files changed, 198 insertions(+)
 create mode 100644 drivers/platform/x86/lenovo-ymc.c

diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 5692385e2..858be0c65 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -470,6 +470,16 @@ config IDEAPAD_LAPTOP
 	  This is a driver for Lenovo IdeaPad netbooks contains drivers for
 	  rfkill switch, hotkey, fan control and backlight control.
 
+config LENOVO_YMC
+	tristate "Lenovo Yoga Tablet Mode Control"
+	depends on ACPI_WMI
+	depends on INPUT
+	depends on IDEAPAD_LAPTOP
+	select INPUT_SPARSEKMAP
+	help
+	  This driver maps the Tablet Mode Control switch to SW_TABLET_MODE input
+	  events for Lenovo Yoga notebooks.
+
 config SENSORS_HDAPS
 	tristate "Thinkpad Hard Drive Active Protection System (hdaps)"
 	depends on INPUT
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 1d3d1b025..10054cdea 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -63,6 +63,7 @@ obj-$(CONFIG_UV_SYSFS)       += uv_sysfs.o
 # IBM Thinkpad and Lenovo
 obj-$(CONFIG_IBM_RTL)		+= ibm_rtl.o
 obj-$(CONFIG_IDEAPAD_LAPTOP)	+= ideapad-laptop.o
+obj-$(CONFIG_LENOVO_YMC)	+= lenovo-ymc.o
 obj-$(CONFIG_SENSORS_HDAPS)	+= hdaps.o
 obj-$(CONFIG_THINKPAD_ACPI)	+= thinkpad_acpi.o
 obj-$(CONFIG_THINKPAD_LMI)	+= think-lmi.o
diff --git a/drivers/platform/x86/ideapad-laptop.h b/drivers/platform/x86/ideapad-laptop.h
index 7dd8ce027..2564cb1cd 100644
--- a/drivers/platform/x86/ideapad-laptop.h
+++ b/drivers/platform/x86/ideapad-laptop.h
@@ -35,6 +35,7 @@ enum {
 	VPCCMD_W_FAN,
 	VPCCMD_R_RF,
 	VPCCMD_W_RF,
+	VPCCMD_W_YMC = 0x2A,
 	VPCCMD_R_FAN = 0x2B,
 	VPCCMD_R_SPECIAL_BUTTONS = 0x31,
 	VPCCMD_W_BL_POWER = 0x33,
diff --git a/drivers/platform/x86/lenovo-ymc.c b/drivers/platform/x86/lenovo-ymc.c
new file mode 100644
index 000000000..5e520a764
--- /dev/null
+++ b/drivers/platform/x86/lenovo-ymc.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * lenovo-ymc.c - Lenovo Yoga Mode Control driver
+ *
+ * Copyright © 2022 Gergo Koteles <soyer@irl.hu>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/acpi.h>
+#include <linux/dmi.h>
+#include <linux/input.h>
+#include <linux/input/sparse-keymap.h>
+#include <linux/wmi.h>
+#include "ideapad-laptop.h"
+
+#define LENOVO_YMC_EVENT_GUID	"06129D99-6083-4164-81AD-F092F9D773A6"
+#define LENOVO_YMC_QUERY_GUID	"09B0EE6E-C3FD-4243-8DA1-7911FF80BB8C"
+
+#define LENOVO_YMC_QUERY_INSTANCE 0
+#define LENOVO_YMC_QUERY_METHOD 0x01
+
+static bool ec_trigger __read_mostly;
+module_param(ec_trigger, bool, 0444);
+MODULE_PARM_DESC(ec_trigger, "Enable EC triggering work-around to force emitting tablet mode events");
+
+static const struct dmi_system_id ec_trigger_quirk_dmi_table[] = {
+	{
+		// Lenovo Yoga 7 14ARB7
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "82QF"),
+		},
+	},
+	{ },
+};
+
+struct lenovo_ymc_private {
+	struct input_dev *input_dev;
+	struct acpi_device *ec_acpi_dev;
+};
+
+static void lenovo_ymc_trigger_ec(struct wmi_device *wdev, struct lenovo_ymc_private *priv)
+{
+	int err;
+	if (!priv->ec_acpi_dev)
+		return;
+	err = write_ec_cmd(priv->ec_acpi_dev->handle, VPCCMD_W_YMC, 1);
+	if (err)
+		dev_warn(&wdev->dev, "Could not write YMC: %d\n", err);
+}
+
+static const struct key_entry lenovo_ymc_keymap[] = {
+	// Laptop
+	{ KE_SW, 0x01, { .sw = { SW_TABLET_MODE, 0 } } },
+	// Tablet
+	{ KE_SW, 0x02, { .sw = { SW_TABLET_MODE, 1 } } },
+	// Drawing Board
+	{ KE_SW, 0x03, { .sw = { SW_TABLET_MODE, 1 } } },
+	// Tent
+	{ KE_SW, 0x04, { .sw = { SW_TABLET_MODE, 1 } } },
+	{ KE_END },
+};
+
+static void lenovo_ymc_notify(struct wmi_device *wdev, union acpi_object *data)
+{
+	struct lenovo_ymc_private *priv = dev_get_drvdata(&wdev->dev);
+
+	u32 input_val = 0;
+	struct acpi_buffer input = {sizeof(input_val), &input_val};
+	struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
+	acpi_status status;
+	union acpi_object *obj;
+	int code;
+
+	status = wmi_evaluate_method(LENOVO_YMC_QUERY_GUID,
+				LENOVO_YMC_QUERY_INSTANCE,
+				LENOVO_YMC_QUERY_METHOD,
+				&input, &output);
+
+	if (ACPI_FAILURE(status)) {
+		dev_warn(&wdev->dev,
+			"Failed to evaluate query method: %s\n",
+			acpi_format_exception(status));
+		return;
+	}
+
+	obj = output.pointer;
+
+	if (obj->type != ACPI_TYPE_INTEGER) {
+		dev_warn(&wdev->dev,
+			"WMI event data is not an integer\n");
+		goto free_obj;
+	}
+	code = obj->integer.value;
+
+	if (!sparse_keymap_report_event(priv->input_dev, code, 1, true))
+		dev_warn(&wdev->dev, "Unknown key %d pressed\n", code);
+
+free_obj:
+	kfree(obj);
+	lenovo_ymc_trigger_ec(wdev, priv);
+}
+
+static void acpi_dev_put_helper(void *p) { acpi_dev_put(p); }
+
+static int lenovo_ymc_probe(struct wmi_device *wdev, const void *ctx)
+{
+	struct input_dev *input_dev;
+	struct lenovo_ymc_private *priv;
+	int err;
+
+	ec_trigger |= dmi_check_system(ec_trigger_quirk_dmi_table);
+
+	priv = devm_kzalloc(&wdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	if (ec_trigger) {
+		pr_debug("Lenovo YMC enable EC triggering.\n");
+		priv->ec_acpi_dev = acpi_dev_get_first_match_dev("VPC2004", NULL, -1);
+
+		if (!priv->ec_acpi_dev) {
+			dev_err(&wdev->dev, "Could not find EC ACPI device.\n");
+			return -ENODEV;
+		}
+		err = devm_add_action_or_reset(&wdev->dev,
+				acpi_dev_put_helper, priv->ec_acpi_dev);
+		if (err) {
+			dev_err(&wdev->dev,
+				"Could not clean up EC ACPI device: %d\n", err);
+			return err;
+		}
+	}
+
+	input_dev = devm_input_allocate_device(&wdev->dev);
+	if (!input_dev)
+		return -ENOMEM;
+
+	input_dev->name = "Lenovo Yoga Tablet Mode Control switch";
+	input_dev->phys = LENOVO_YMC_EVENT_GUID "/input0";
+	input_dev->id.bustype = BUS_HOST;
+	input_dev->dev.parent = &wdev->dev;
+	err = sparse_keymap_setup(input_dev, lenovo_ymc_keymap, NULL);
+	if (err) {
+		dev_err(&wdev->dev,
+			"Could not set up input device keymap: %d\n", err);
+		return err;
+	}
+
+	err = input_register_device(input_dev);
+	if (err) {
+		dev_err(&wdev->dev,
+			"Could not register input device: %d\n", err);
+		return err;
+	}
+
+	priv->input_dev = input_dev;
+	dev_set_drvdata(&wdev->dev, priv);
+
+	// Report the state for the first time on probe
+	lenovo_ymc_trigger_ec(wdev, priv);
+	lenovo_ymc_notify(wdev, NULL);
+	return 0;
+}
+
+static const struct wmi_device_id lenovo_ymc_wmi_id_table[] = {
+	{ .guid_string = LENOVO_YMC_EVENT_GUID },
+	{ }
+};
+MODULE_DEVICE_TABLE(wmi, lenovo_ymc_wmi_id_table);
+
+static struct wmi_driver lenovo_ymc_driver = {
+	.driver = {
+		.name = "lenovo-ymc",
+	},
+	.id_table = lenovo_ymc_wmi_id_table,
+	.probe = lenovo_ymc_probe,
+	.notify = lenovo_ymc_notify,
+};
+
+module_wmi_driver(lenovo_ymc_driver);
+
+MODULE_AUTHOR("Gergo Koteles <soyer@irl.hu>");
+MODULE_DESCRIPTION("Lenovo Yoga Mode Control driver");
+MODULE_LICENSE("GPL");
-- 
2.40.0

Re: [PATCH v3 0/2] platform/x86: Add driver for Yoga Tablet mode switch

[Armin Wolf]

Am 29.03.23 um 03:45 schrieb Andrew Kallmeyer:

> This driver maps the Lenovo Yoga tablet mode switch to a SW_TABLET_MODE input
> device. This will make the tablet status available to desktop environments.
>
> This patch series is the result of the discussion at
> https://lore.kernel.org/r/CAG4kvq9US=-NjyXFMzJYu2zCJryJWtOc7FGZbrewpgCDjdAkbg@mail.gmail.com/
>
> I decided to follow-up on the patch Gergo wrote and respond to the review
> comments to get it merged and available for everyone.
>
> Gergo and I have tested this on the Yoga 7 14ARB7, and the Yoga 7 14AIL7
> respectively. Additionally, according to reports at
> https://github.com/lukas-w/yoga-usage-mode, which uses the same WMI devices,
> this driver should work with:
> Yoga C940, Ideapad flex 14API, Yoga 9 14IAP7, Yoga 7 14ARB7, etc.
>
> v1: https://lore.kernel.org/r/20230310041726.217447-1-kallmeyeras@gmail.com/
> v2: https://lore.kernel.org/r/20230323025200.5462-1-kallmeyeras@gmail.com/
> The diff since v2 is as follows:
>
> --- a/drivers/platform/x86/lenovo-ymc.c
> +++ b/drivers/platform/x86/lenovo-ymc.c
> @@ -21,8 +21,8 @@
>   #define LENOVO_YMC_QUERY_METHOD 0x01
>
>   static bool ec_trigger __read_mostly;
> -module_param(ec_trigger, bool, 0644);
> -MODULE_PARM_DESC(ec_trigger, "Enable EC triggering to emit YMC events");
> +module_param(ec_trigger, bool, 0444);
> +MODULE_PARM_DESC(ec_trigger, "Enable EC triggering work-around to force emitting tablet mode events");
>
>   static const struct dmi_system_id ec_trigger_quirk_dmi_table[] = {
>   	{
> @@ -43,8 +43,7 @@ struct lenovo_ymc_private {
>   static void lenovo_ymc_trigger_ec(struct wmi_device *wdev, struct lenovo_ymc_private *priv)
>   {
>   	int err;
> -
> -	if (!ec_trigger || !priv || !priv->ec_acpi_dev)
> +	if (!priv->ec_acpi_dev)
>   		return;
>   	err = write_ec_cmd(priv->ec_acpi_dev->handle, VPCCMD_W_YMC, 1);
>   	if (err)
> @@ -103,11 +102,7 @@ static void lenovo_ymc_notify(struct wmi_device *wdev, union acpi_object *data)
>   	lenovo_ymc_trigger_ec(wdev, priv);
>   }
>
> -static void lenovo_ymc_remove(struct wmi_device *wdev)
> -{
> -	struct lenovo_ymc_private *priv = dev_get_drvdata(&wdev->dev);
> -	acpi_dev_put(priv->ec_acpi_dev);
> -}
> +static void acpi_dev_put_helper(void *p) { acpi_dev_put(p); }
>
>   static int lenovo_ymc_probe(struct wmi_device *wdev, const void *ctx)
>   {
> @@ -124,10 +119,18 @@ static int lenovo_ymc_probe(struct wmi_device *wdev, const void *ctx)
>   	if (ec_trigger) {
>   		pr_debug("Lenovo YMC enable EC triggering.\n");
>   		priv->ec_acpi_dev = acpi_dev_get_first_match_dev("VPC2004", NULL, -1);
> +
>   		if (!priv->ec_acpi_dev) {
>   			dev_err(&wdev->dev, "Could not find EC ACPI device.\n");
>   			return -ENODEV;
>   		}
> +		err = devm_add_action_or_reset(&wdev->dev,
> +				acpi_dev_put_helper, priv->ec_acpi_dev);
> +		if (err) {
> +			dev_err(&wdev->dev,
> +				"Could not clean up EC ACPI device: %d\n", err);
> +			return err;
> +		}
>   	}
>
>   	input_dev = devm_input_allocate_device(&wdev->dev);
> @@ -138,9 +141,6 @@ static int lenovo_ymc_probe(struct wmi_device *wdev, const void *ctx)
>   	input_dev->phys = LENOVO_YMC_EVENT_GUID "/input0";
>   	input_dev->id.bustype = BUS_HOST;
>   	input_dev->dev.parent = &wdev->dev;
> -
> -	input_set_capability(input_dev, EV_SW, SW_TABLET_MODE);
> -
>   	err = sparse_keymap_setup(input_dev, lenovo_ymc_keymap, NULL);
>   	if (err) {
>   		dev_err(&wdev->dev,
> @@ -177,7 +177,6 @@ static struct wmi_driver lenovo_ymc_driver = {
>   	.id_table = lenovo_ymc_wmi_id_table,
>   	.probe = lenovo_ymc_probe,
>   	.notify = lenovo_ymc_notify,
> -	.remove = lenovo_ymc_remove,
>   };
>
>   module_wmi_driver(lenovo_ymc_driver);
>
> Andrew Kallmeyer (1):
>    platform/x86: Move ideapad ACPI helpers to a new header
>
> Gergo Koteles (1):
>    platform/x86: Add driver for Yoga Tablet Mode switch
>
>   drivers/platform/x86/Kconfig          |  10 ++
>   drivers/platform/x86/Makefile         |   1 +
>   drivers/platform/x86/ideapad-laptop.c | 135 +------------------
>   drivers/platform/x86/ideapad-laptop.h | 152 +++++++++++++++++++++
>   drivers/platform/x86/lenovo-ymc.c     | 185 ++++++++++++++++++++++++++
>   5 files changed, 349 insertions(+), 134 deletions(-)
>   create mode 100644 drivers/platform/x86/ideapad-laptop.h
>   create mode 100644 drivers/platform/x86/lenovo-ymc.c
>
Hi,

while compile-testing your patch series, i noticed that there are a couple of checkpatch warnings.
For lenovo-ymc.c:

WARNING: Missing a blank line after declarations
#46: FILE: drivers/platform/x86/lenovo-ymc.c:46:
+	int err;
+	if (!priv->ec_acpi_dev)

CHECK: Alignment should match open parenthesis
#77: FILE: drivers/platform/x86/lenovo-ymc.c:77:
+	status = wmi_evaluate_method(LENOVO_YMC_QUERY_GUID,
+				LENOVO_YMC_QUERY_INSTANCE,

CHECK: Alignment should match open parenthesis
#83: FILE: drivers/platform/x86/lenovo-ymc.c:83:
+		dev_warn(&wdev->dev,
+			"Failed to evaluate query method: %s\n",

CHECK: Alignment should match open parenthesis
#92: FILE: drivers/platform/x86/lenovo-ymc.c:92:
+		dev_warn(&wdev->dev,
+			"WMI event data is not an integer\n");

CHECK: Alignment should match open parenthesis
#128: FILE: drivers/platform/x86/lenovo-ymc.c:128:
+		err = devm_add_action_or_reset(&wdev->dev,
+				acpi_dev_put_helper, priv->ec_acpi_dev);

For ideapad-laptop.h:

WARNING: Improper SPDX comment style for 'drivers/platform/x86/ideapad-laptop.h', please use '/*' instead
#1: FILE: drivers/platform/x86/ideapad-laptop.h:1:
+// SPDX-License-Identifier: GPL-2.0-or-later

WARNING: Missing or malformed SPDX-License-Identifier tag in line 1
#1: FILE: drivers/platform/x86/ideapad-laptop.h:1:
+// SPDX-License-Identifier: GPL-2.0-or-later

CHECK: line length of 112 exceeds 100 columns
#44: FILE: drivers/platform/x86/ideapad-laptop.h:44:
+static inline int eval_int_with_arg(acpi_handle handle, const char *name, unsigned long arg, unsigned long *res)

All these checkpatch warnings are minor style issues (except the malformed SPDX tag in ideapad-laptop.h),
but it would be nice if those would get fixed too.

Armin Wolf

Re: [PATCH v3 0/2] platform/x86: Add driver for Yoga Tablet mode switch

[André Apitzsch]

Am Dienstag, dem 28.03.2023 um 18:45 -0700 schrieb Andrew Kallmeyer:
> This driver maps the Lenovo Yoga tablet mode switch to a SW_TABLET_MODE input
> device. This will make the tablet status available to desktop environments.
> 
> This patch series is the result of the discussion at
> https://lore.kernel.org/r/CAG4kvq9US=-NjyXFMzJYu2zCJryJWtOc7FGZbrewpgCDjdAkbg@mail.gmail.com/
> 
> I decided to follow-up on the patch Gergo wrote and respond to the review
> comments to get it merged and available for everyone.
> 
> Gergo and I have tested this on the Yoga 7 14ARB7, and the Yoga 7 14AIL7
> respectively. Additionally, according to reports at
> https://github.com/lukas-w/yoga-usage-mode, which uses the same WMI devices,
> this driver should work with:
> Yoga C940, Ideapad flex 14API, Yoga 9 14IAP7, Yoga 7 14ARB7, etc.
> 
> v1: https://lore.kernel.org/r/20230310041726.217447-1-kallmeyeras@gmail.com/
> v2: https://lore.kernel.org/r/20230323025200.5462-1-kallmeyeras@gmail.com/
> The diff since v2 is as follows:
> 
> [..]
> 
> Andrew Kallmeyer (1):
>   platform/x86: Move ideapad ACPI helpers to a new header
> 
> Gergo Koteles (1):
>   platform/x86: Add driver for Yoga Tablet Mode switch
> 
>  drivers/platform/x86/Kconfig          |  10 ++
>  drivers/platform/x86/Makefile         |   1 +
>  drivers/platform/x86/ideapad-laptop.c | 135 +------------------
>  drivers/platform/x86/ideapad-laptop.h | 152 +++++++++++++++++++++
>  drivers/platform/x86/lenovo-ymc.c     | 185 ++++++++++++++++++++++++++
>  5 files changed, 349 insertions(+), 134 deletions(-)
>  create mode 100644 drivers/platform/x86/ideapad-laptop.h
>  create mode 100644 drivers/platform/x86/lenovo-ymc.c
> 

Hi Andrew,

it seems my last tested-by got lost, when preparing the this patch
version or was ignored because of the amount of code changes.

Anyway, tested again on Lenovo ThinkBook 14s Yoga ITL.

Tested-by: André Apitzsch <git@apitzsch.eu>

Best regards,
André

Re: [PATCH v3 2/2] platform/x86: Add driver for Yoga Tablet Mode switch

[Hans de Goede]

Hi Andrew,

Thank you for your patch. I have merged this now,
with tiny code cleanups squashed in.

I've described the code-cleanups below (inline) :

On 3/29/23 03:45, Andrew Kallmeyer wrote:
> From: Gergo Koteles <soyer@irl.hu>
> 
> This WMI driver for the tablet mode control switch for Lenovo Yoga
> notebooks was originally written by Gergo Koteles. The mode is mapped to
> a SW_TABLET_MODE switch capable input device.
> 
> Andrew followed the suggestions that were posted in reply to Gergo's RFC
> patch, and on the v1 & v2 versions of this patch to follow-up and get it
> merged.
> 
> Changes from Gergo's RFC:
> 
>  - Refactored obtaining a reference to the EC ACPI device needed for the
>    quirk implementation as suggested by Hans de Goede
>  - Applied small fixes and switched to always registering handles with
>    the driver for automatic cleanup as suggested by Barnabás Pőcze.
>  - Merged the lenovo_ymc_trigger_ec function with the
>    ideapad_trigger_ymc_next_read function since it was no longer
>    external.
>  - Added the word "Tablet" to the driver description to hopefully make
>    it more clear.
>  - Fixed the LENOVO_YMC_QUERY_METHOD ID and the name string for the EC
>    APCI device trigged for the quirk
>  - Triggered the input event on probe so that the initial tablet mode
>    state when the driver is loaded is reported to userspace as suggested
>    by Armin Wolf.
>  - Restricted the permissions of the ec_trigger parameter as suggested
>    by Armin Wolf. Also updated the description.
> 
> We have tested this on the Yoga 7 14AIL7 for the non-quirk path and on
> the Yoga 7 14ARB7 which has the firmware bug that requires triggering
> the embedded controller to send the mode change events. This workaround
> is also used by the Windows drivers.
> 
> According to reports at https://github.com/lukas-w/yoga-usage-mode,
> which uses the same WMI devices, the following models should also work:
> Yoga C940, Ideapad flex 14API, Yoga 9 14IAP7, Yoga 7 14ARB7, etc.
> 
> Signed-off-by: Gergo Koteles <soyer@irl.hu>
> Co-developed-by: Andrew Kallmeyer <kallmeyeras@gmail.com>
> Signed-off-by: Andrew Kallmeyer <kallmeyeras@gmail.com>
> Link: https://lore.kernel.org/r/20221004214332.35934-1-soyer@irl.hu/
> Link: https://lore.kernel.org/r/20230310041726.217447-1-kallmeyeras@gmail.com/
> Link: https://lore.kernel.org/r/20230323025200.5462-1-kallmeyeras@gmail.com/
> ---
>  drivers/platform/x86/Kconfig          |  10 ++
>  drivers/platform/x86/Makefile         |   1 +
>  drivers/platform/x86/ideapad-laptop.h |   1 +
>  drivers/platform/x86/lenovo-ymc.c     | 186 ++++++++++++++++++++++++++
>  4 files changed, 198 insertions(+)
>  create mode 100644 drivers/platform/x86/lenovo-ymc.c
> 
> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
> index 5692385e2..858be0c65 100644
> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -470,6 +470,16 @@ config IDEAPAD_LAPTOP
>  	  This is a driver for Lenovo IdeaPad netbooks contains drivers for
>  	  rfkill switch, hotkey, fan control and backlight control.
>  
> +config LENOVO_YMC
> +	tristate "Lenovo Yoga Tablet Mode Control"
> +	depends on ACPI_WMI
> +	depends on INPUT
> +	depends on IDEAPAD_LAPTOP

I don't believe that we need any symbols from IDEAPAD_LAPTOP with
the new static inline helpers, so I've dropped this depends on.

> +	select INPUT_SPARSEKMAP
> +	help
> +	  This driver maps the Tablet Mode Control switch to SW_TABLET_MODE input
> +	  events for Lenovo Yoga notebooks.
> +
>  config SENSORS_HDAPS
>  	tristate "Thinkpad Hard Drive Active Protection System (hdaps)"
>  	depends on INPUT
> diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
> index 1d3d1b025..10054cdea 100644
> --- a/drivers/platform/x86/Makefile
> +++ b/drivers/platform/x86/Makefile
> @@ -63,6 +63,7 @@ obj-$(CONFIG_UV_SYSFS)       += uv_sysfs.o
>  # IBM Thinkpad and Lenovo
>  obj-$(CONFIG_IBM_RTL)		+= ibm_rtl.o
>  obj-$(CONFIG_IDEAPAD_LAPTOP)	+= ideapad-laptop.o
> +obj-$(CONFIG_LENOVO_YMC)	+= lenovo-ymc.o
>  obj-$(CONFIG_SENSORS_HDAPS)	+= hdaps.o
>  obj-$(CONFIG_THINKPAD_ACPI)	+= thinkpad_acpi.o
>  obj-$(CONFIG_THINKPAD_LMI)	+= think-lmi.o
> diff --git a/drivers/platform/x86/ideapad-laptop.h b/drivers/platform/x86/ideapad-laptop.h
> index 7dd8ce027..2564cb1cd 100644
> --- a/drivers/platform/x86/ideapad-laptop.h
> +++ b/drivers/platform/x86/ideapad-laptop.h
> @@ -35,6 +35,7 @@ enum {
>  	VPCCMD_W_FAN,
>  	VPCCMD_R_RF,
>  	VPCCMD_W_RF,
> +	VPCCMD_W_YMC = 0x2A,
>  	VPCCMD_R_FAN = 0x2B,
>  	VPCCMD_R_SPECIAL_BUTTONS = 0x31,
>  	VPCCMD_W_BL_POWER = 0x33,
> diff --git a/drivers/platform/x86/lenovo-ymc.c b/drivers/platform/x86/lenovo-ymc.c
> new file mode 100644
> index 000000000..5e520a764
> --- /dev/null
> +++ b/drivers/platform/x86/lenovo-ymc.c
> @@ -0,0 +1,186 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * lenovo-ymc.c - Lenovo Yoga Mode Control driver
> + *
> + * Copyright © 2022 Gergo Koteles <soyer@irl.hu>
> + */
> +
> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> +
> +#include <linux/acpi.h>
> +#include <linux/dmi.h>
> +#include <linux/input.h>
> +#include <linux/input/sparse-keymap.h>
> +#include <linux/wmi.h>
> +#include "ideapad-laptop.h"
> +
> +#define LENOVO_YMC_EVENT_GUID	"06129D99-6083-4164-81AD-F092F9D773A6"
> +#define LENOVO_YMC_QUERY_GUID	"09B0EE6E-C3FD-4243-8DA1-7911FF80BB8C"
> +
> +#define LENOVO_YMC_QUERY_INSTANCE 0
> +#define LENOVO_YMC_QUERY_METHOD 0x01
> +
> +static bool ec_trigger __read_mostly;
> +module_param(ec_trigger, bool, 0444);
> +MODULE_PARM_DESC(ec_trigger, "Enable EC triggering work-around to force emitting tablet mode events");
> +
> +static const struct dmi_system_id ec_trigger_quirk_dmi_table[] = {
> +	{
> +		// Lenovo Yoga 7 14ARB7

Generally speaking we prefer C-style /* */ comments in pdx86,
so I've converted all comments to this style.

> +		.matches = {
> +			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
> +			DMI_MATCH(DMI_PRODUCT_NAME, "82QF"),
> +		},
> +	},
> +	{ },

Since this is a terminator, it should not have a trailing comma (removed).

> +};
> +
> +struct lenovo_ymc_private {
> +	struct input_dev *input_dev;
> +	struct acpi_device *ec_acpi_dev;
> +};
> +
> +static void lenovo_ymc_trigger_ec(struct wmi_device *wdev, struct lenovo_ymc_private *priv)
> +{
> +	int err;

There must be an empty line between declarations and
the first statement (added).

> +	if (!priv->ec_acpi_dev)
> +		return;
> +	err = write_ec_cmd(priv->ec_acpi_dev->handle, VPCCMD_W_YMC, 1);
> +	if (err)
> +		dev_warn(&wdev->dev, "Could not write YMC: %d\n", err);
> +}
> +
> +static const struct key_entry lenovo_ymc_keymap[] = {
> +	// Laptop
> +	{ KE_SW, 0x01, { .sw = { SW_TABLET_MODE, 0 } } },
> +	// Tablet
> +	{ KE_SW, 0x02, { .sw = { SW_TABLET_MODE, 1 } } },
> +	// Drawing Board
> +	{ KE_SW, 0x03, { .sw = { SW_TABLET_MODE, 1 } } },
> +	// Tent
> +	{ KE_SW, 0x04, { .sw = { SW_TABLET_MODE, 1 } } },
> +	{ KE_END },
> +};
> +
> +static void lenovo_ymc_notify(struct wmi_device *wdev, union acpi_object *data)
> +{
> +	struct lenovo_ymc_private *priv = dev_get_drvdata(&wdev->dev);
> +

And this empty line here looks weird. I have removed this and also
moved the status declaration down a bit since normally we order
variable declarations from long declaration to short declarations
(known as reverse christmas tree order).

> +	u32 input_val = 0;
> +	struct acpi_buffer input = {sizeof(input_val), &input_val};
> +	struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
> +	acpi_status status;
> +	union acpi_object *obj;
> +	int code;
> +
> +	status = wmi_evaluate_method(LENOVO_YMC_QUERY_GUID,
> +				LENOVO_YMC_QUERY_INSTANCE,
> +				LENOVO_YMC_QUERY_METHOD,
> +				&input, &output);
> +
> +	if (ACPI_FAILURE(status)) {
> +		dev_warn(&wdev->dev,
> +			"Failed to evaluate query method: %s\n",
> +			acpi_format_exception(status));
> +		return;
> +	}
> +
> +	obj = output.pointer;
> +
> +	if (obj->type != ACPI_TYPE_INTEGER) {
> +		dev_warn(&wdev->dev,
> +			"WMI event data is not an integer\n");
> +		goto free_obj;
> +	}
> +	code = obj->integer.value;
> +
> +	if (!sparse_keymap_report_event(priv->input_dev, code, 1, true))
> +		dev_warn(&wdev->dev, "Unknown key %d pressed\n", code);
> +
> +free_obj:
> +	kfree(obj);
> +	lenovo_ymc_trigger_ec(wdev, priv);
> +}
> +
> +static void acpi_dev_put_helper(void *p) { acpi_dev_put(p); }
> +
> +static int lenovo_ymc_probe(struct wmi_device *wdev, const void *ctx)
> +{
> +	struct input_dev *input_dev;
> +	struct lenovo_ymc_private *priv;
> +	int err;
> +
> +	ec_trigger |= dmi_check_system(ec_trigger_quirk_dmi_table);
> +
> +	priv = devm_kzalloc(&wdev->dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	if (ec_trigger) {
> +		pr_debug("Lenovo YMC enable EC triggering.\n");
> +		priv->ec_acpi_dev = acpi_dev_get_first_match_dev("VPC2004", NULL, -1);
> +
> +		if (!priv->ec_acpi_dev) {
> +			dev_err(&wdev->dev, "Could not find EC ACPI device.\n");
> +			return -ENODEV;
> +		}
> +		err = devm_add_action_or_reset(&wdev->dev,
> +				acpi_dev_put_helper, priv->ec_acpi_dev);
> +		if (err) {
> +			dev_err(&wdev->dev,
> +				"Could not clean up EC ACPI device: %d\n", err);
> +			return err;
> +		}
> +	}
> +
> +	input_dev = devm_input_allocate_device(&wdev->dev);
> +	if (!input_dev)
> +		return -ENOMEM;
> +
> +	input_dev->name = "Lenovo Yoga Tablet Mode Control switch";
> +	input_dev->phys = LENOVO_YMC_EVENT_GUID "/input0";
> +	input_dev->id.bustype = BUS_HOST;
> +	input_dev->dev.parent = &wdev->dev;
> +	err = sparse_keymap_setup(input_dev, lenovo_ymc_keymap, NULL);
> +	if (err) {
> +		dev_err(&wdev->dev,
> +			"Could not set up input device keymap: %d\n", err);
> +		return err;
> +	}
> +
> +	err = input_register_device(input_dev);
> +	if (err) {
> +		dev_err(&wdev->dev,
> +			"Could not register input device: %d\n", err);
> +		return err;
> +	}
> +
> +	priv->input_dev = input_dev;
> +	dev_set_drvdata(&wdev->dev, priv);
> +
> +	// Report the state for the first time on probe
> +	lenovo_ymc_trigger_ec(wdev, priv);
> +	lenovo_ymc_notify(wdev, NULL);
> +	return 0;
> +}
> +
> +static const struct wmi_device_id lenovo_ymc_wmi_id_table[] = {
> +	{ .guid_string = LENOVO_YMC_EVENT_GUID },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(wmi, lenovo_ymc_wmi_id_table);
> +
> +static struct wmi_driver lenovo_ymc_driver = {
> +	.driver = {
> +		.name = "lenovo-ymc",
> +	},
> +	.id_table = lenovo_ymc_wmi_id_table,
> +	.probe = lenovo_ymc_probe,
> +	.notify = lenovo_ymc_notify,
> +};
> +
> +module_wmi_driver(lenovo_ymc_driver);
> +
> +MODULE_AUTHOR("Gergo Koteles <soyer@irl.hu>");
> +MODULE_DESCRIPTION("Lenovo Yoga Mode Control driver");
> +MODULE_LICENSE("GPL");

Thank you for your patch, I've applied this patch to my review-hans 
branch:
https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=review-hans

Once I've run some tests on this branch the patches there will be
added to the platform-drivers-x86/for-next branch and eventually
will be included in the pdx86 pull-request to Linus for the next
merge-window.

Regards,

Hans

Re: [PATCH v3 2/2] platform/x86: Add driver for Yoga Tablet Mode switch

[Andrew Kallmeyer]

On Thu, Apr 6, 2023 at 3:34 AM Hans de Goede <hdegoede@redhat.com> wrote:
>
> Hi Andrew,
>
> Thank you for your patch. I have merged this now,
> with tiny code cleanups squashed in.

Thanks for all the help Hans, and everyone else too! I thought I would
need to send another patch version tonight, but I'm glad to hear this
is getting merged!

Thanks,
Andrew