drivers/platform/x86/intel-vbtn.c - third_party/linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 /*
  *  Intel Virtual Button driver for Windows 8.1+
  *
  *  Copyright (C) 2016 AceLan Kao <acelan.kao@canonical.com>
  *  Copyright (C) 2016 Alex Hung <alex.hung@canonical.com>
  */

 #include <linux/acpi.h>
 #include <linux/dmi.h>
 #include <linux/input.h>
 #include <linux/input/sparse-keymap.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/suspend.h>

 /* When NOT in tablet mode, VGBS returns with the flag 0x40 */
 #define TABLET_MODE_FLAG 0x40

 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("AceLan Kao");

 static const struct acpi_device_id intel_vbtn_ids[] = {
 	{"INT33D6", 0},
 	{"", 0},
 };

 /* In theory, these are HID usages. */
 static const struct key_entry intel_vbtn_keymap[] = {
 	{ KE_KEY, 0xC0, { KEY_POWER } },	/* power key press */
 	{ KE_IGNORE, 0xC1, { KEY_POWER } },	/* power key release */
 	{ KE_KEY, 0xC2, { KEY_LEFTMETA } },		/* 'Windows' key press */
 	{ KE_KEY, 0xC3, { KEY_LEFTMETA } },		/* 'Windows' key release */
 	{ KE_KEY, 0xC4, { KEY_VOLUMEUP } },		/* volume-up key press */
 	{ KE_IGNORE, 0xC5, { KEY_VOLUMEUP } },		/* volume-up key release */
 	{ KE_KEY, 0xC6, { KEY_VOLUMEDOWN } },		/* volume-down key press */
 	{ KE_IGNORE, 0xC7, { KEY_VOLUMEDOWN } },	/* volume-down key release */
 	{ KE_KEY,    0xC8, { KEY_ROTATE_LOCK_TOGGLE } },	/* rotate-lock key press */
 	{ KE_KEY,    0xC9, { KEY_ROTATE_LOCK_TOGGLE } },	/* rotate-lock key release */
 	{ KE_SW,     0xCC, { .sw = { SW_TABLET_MODE, 1 } } },	/* Tablet */
 	{ KE_SW,     0xCD, { .sw = { SW_TABLET_MODE, 0 } } },	/* Laptop */
 	{ KE_END },
 };

 struct intel_vbtn_priv {
 	struct input_dev *input_dev;
 	bool wakeup_mode;
 };

 static int intel_vbtn_input_setup(struct platform_device *device)
 {
 	struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
 	int ret;

 	priv->input_dev = devm_input_allocate_device(&device->dev);
 	if (!priv->input_dev)
 		return -ENOMEM;

 	ret = sparse_keymap_setup(priv->input_dev, intel_vbtn_keymap, NULL);
 	if (ret)
 		return ret;

 	priv->input_dev->dev.parent = &device->dev;
 	priv->input_dev->name = "Intel Virtual Button driver";
 	priv->input_dev->id.bustype = BUS_HOST;

 	return input_register_device(priv->input_dev);
 }

 static void notify_handler(acpi_handle handle, u32 event, void *context)
 {
 	struct platform_device *device = context;
 	struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
 	unsigned int val = !(event & 1); /* Even=press, Odd=release */
 	const struct key_entry *ke_rel;
 	bool autorelease;

 	if (priv->wakeup_mode) {
 		if (sparse_keymap_entry_from_scancode(priv->input_dev, event)) {
 			pm_wakeup_hard_event(&device->dev);
 			return;
 		}
 		goto out_unknown;
 	}

 	/*
 	 * Even press events are autorelease if there is no corresponding odd
 	 * release event, or if the odd event is KE_IGNORE.
 	 */
 	ke_rel = sparse_keymap_entry_from_scancode(priv->input_dev, event | 1);
 	autorelease = val && (!ke_rel || ke_rel->type == KE_IGNORE);

 	if (sparse_keymap_report_event(priv->input_dev, event, val, autorelease))
 		return;

 out_unknown:
 	dev_dbg(&device->dev, "unknown event index 0x%x\n", event);
 }

 static void detect_tablet_mode(struct platform_device *device)
 {
 	const char *chassis_type = dmi_get_system_info(DMI_CHASSIS_TYPE);
 	struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
 	acpi_handle handle = ACPI_HANDLE(&device->dev);
 	struct acpi_buffer vgbs_output = { ACPI_ALLOCATE_BUFFER, NULL };
 	union acpi_object *obj;
 	acpi_status status;
 	int m;

 	if (!(chassis_type && strcmp(chassis_type, "31") == 0))
 		goto out;

 	status = acpi_evaluate_object(handle, "VGBS", NULL, &vgbs_output);
 	if (ACPI_FAILURE(status))
 		goto out;

 	obj = vgbs_output.pointer;
 	if (!(obj && obj->type == ACPI_TYPE_INTEGER))
 		goto out;

 	m = !(obj->integer.value & TABLET_MODE_FLAG);
 	input_report_switch(priv->input_dev, SW_TABLET_MODE, m);
 out:
 	kfree(vgbs_output.pointer);
 }

 static int intel_vbtn_probe(struct platform_device *device)
 {
 	acpi_handle handle = ACPI_HANDLE(&device->dev);
 	struct intel_vbtn_priv *priv;
 	acpi_status status;
 	int err;

 	status = acpi_evaluate_object(handle, "VBDL", NULL, NULL);
 	if (ACPI_FAILURE(status)) {
 		dev_warn(&device->dev, "failed to read Intel Virtual Button driver\n");
 		return -ENODEV;
 	}

 	priv = devm_kzalloc(&device->dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
 	dev_set_drvdata(&device->dev, priv);

 	err = intel_vbtn_input_setup(device);
 	if (err) {
 		pr_err("Failed to setup Intel Virtual Button\n");
 		return err;
 	}

 	detect_tablet_mode(device);

 	status = acpi_install_notify_handler(handle,
 					     ACPI_DEVICE_NOTIFY,
 					     notify_handler,
 					     device);
 	if (ACPI_FAILURE(status))
 		return -EBUSY;

 	device_init_wakeup(&device->dev, true);
 	return 0;
 }

 static int intel_vbtn_remove(struct platform_device *device)
 {
 	acpi_handle handle = ACPI_HANDLE(&device->dev);

 	device_init_wakeup(&device->dev, false);
 	acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);

 	/*
 	 * Even if we failed to shut off the event stream, we can still
 	 * safely detach from the device.
 	 */
 	return 0;
 }

 static int intel_vbtn_pm_prepare(struct device *dev)
 {
 	struct intel_vbtn_priv *priv = dev_get_drvdata(dev);

 	priv->wakeup_mode = true;
 	return 0;
 }

 static int intel_vbtn_pm_resume(struct device *dev)
 {
 	struct intel_vbtn_priv *priv = dev_get_drvdata(dev);

 	priv->wakeup_mode = false;
 	return 0;
 }

 static const struct dev_pm_ops intel_vbtn_pm_ops = {
 	.prepare = intel_vbtn_pm_prepare,
 	.resume = intel_vbtn_pm_resume,
 	.restore = intel_vbtn_pm_resume,
 	.thaw = intel_vbtn_pm_resume,
 };

 static struct platform_driver intel_vbtn_pl_driver = {
 	.driver = {
 		.name = "intel-vbtn",
 		.acpi_match_table = intel_vbtn_ids,
 		.pm = &intel_vbtn_pm_ops,
 	},
 	.probe = intel_vbtn_probe,
 	.remove = intel_vbtn_remove,
 };
 MODULE_DEVICE_TABLE(acpi, intel_vbtn_ids);

 static acpi_status __init
 check_acpi_dev(acpi_handle handle, u32 lvl, void *context, void **rv)
 {
 	const struct acpi_device_id *ids = context;
 	struct acpi_device *dev;

 	if (acpi_bus_get_device(handle, &dev) != 0)
 		return AE_OK;

 	if (acpi_match_device_ids(dev, ids) == 0)
 		if (acpi_create_platform_device(dev, NULL))
 			dev_info(&dev->dev,
 				 "intel-vbtn: created platform device\n");

 	return AE_OK;
 }

 static int __init intel_vbtn_init(void)
 {
 	acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
 			    ACPI_UINT32_MAX, check_acpi_dev, NULL,
 			    (void *)intel_vbtn_ids, NULL);

 	return platform_driver_register(&intel_vbtn_pl_driver);
 }
 module_init(intel_vbtn_init);

 static void __exit intel_vbtn_exit(void)
 {
 	platform_driver_unregister(&intel_vbtn_pl_driver);
 }
 module_exit(intel_vbtn_exit);
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Intel Virtual Button driver for Windows 8.1+
	*
	* Copyright (C) 2016 AceLan Kao <acelan.kao@canonical.com>
	* Copyright (C) 2016 Alex Hung <alex.hung@canonical.com>
	*/

	#include <linux/acpi.h>
	#include <linux/dmi.h>
	#include <linux/input.h>
	#include <linux/input/sparse-keymap.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/platform_device.h>
	#include <linux/suspend.h>

	/* When NOT in tablet mode, VGBS returns with the flag 0x40 */
	#define TABLET_MODE_FLAG 0x40

	MODULE_LICENSE("GPL");
	MODULE_AUTHOR("AceLan Kao");

	static const struct acpi_device_id intel_vbtn_ids[] = {
	{"INT33D6", 0},
	{"", 0},
	};

	/* In theory, these are HID usages. */
	static const struct key_entry intel_vbtn_keymap[] = {
	{ KE_KEY, 0xC0, { KEY_POWER } }, /* power key press */
	{ KE_IGNORE, 0xC1, { KEY_POWER } }, /* power key release */
	{ KE_KEY, 0xC2, { KEY_LEFTMETA } }, /* 'Windows' key press */
	{ KE_KEY, 0xC3, { KEY_LEFTMETA } }, /* 'Windows' key release */
	{ KE_KEY, 0xC4, { KEY_VOLUMEUP } }, /* volume-up key press */
	{ KE_IGNORE, 0xC5, { KEY_VOLUMEUP } }, /* volume-up key release */
	{ KE_KEY, 0xC6, { KEY_VOLUMEDOWN } }, /* volume-down key press */
	{ KE_IGNORE, 0xC7, { KEY_VOLUMEDOWN } }, /* volume-down key release */
	{ KE_KEY, 0xC8, { KEY_ROTATE_LOCK_TOGGLE } }, /* rotate-lock key press */
	{ KE_KEY, 0xC9, { KEY_ROTATE_LOCK_TOGGLE } }, /* rotate-lock key release */
	{ KE_SW, 0xCC, { .sw = { SW_TABLET_MODE, 1 } } }, /* Tablet */
	{ KE_SW, 0xCD, { .sw = { SW_TABLET_MODE, 0 } } }, /* Laptop */
	{ KE_END },
	};

	struct intel_vbtn_priv {
	struct input_dev *input_dev;
	bool wakeup_mode;
	};

	static int intel_vbtn_input_setup(struct platform_device *device)
	{
	struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
	int ret;

	priv->input_dev = devm_input_allocate_device(&device->dev);
	if (!priv->input_dev)
	return -ENOMEM;

	ret = sparse_keymap_setup(priv->input_dev, intel_vbtn_keymap, NULL);
	if (ret)
	return ret;

	priv->input_dev->dev.parent = &device->dev;
	priv->input_dev->name = "Intel Virtual Button driver";
	priv->input_dev->id.bustype = BUS_HOST;

	return input_register_device(priv->input_dev);
	}

	static void notify_handler(acpi_handle handle, u32 event, void *context)
	{
	struct platform_device *device = context;
	struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
	unsigned int val = !(event & 1); /* Even=press, Odd=release */
	const struct key_entry *ke_rel;
	bool autorelease;

	if (priv->wakeup_mode) {
	if (sparse_keymap_entry_from_scancode(priv->input_dev, event)) {
	pm_wakeup_hard_event(&device->dev);
	return;
	}
	goto out_unknown;
	}

	/*
	* Even press events are autorelease if there is no corresponding odd
	* release event, or if the odd event is KE_IGNORE.
	*/
	ke_rel = sparse_keymap_entry_from_scancode(priv->input_dev, event \| 1);
	autorelease = val && (!ke_rel \|\| ke_rel->type == KE_IGNORE);

	if (sparse_keymap_report_event(priv->input_dev, event, val, autorelease))
	return;

	out_unknown:
	dev_dbg(&device->dev, "unknown event index 0x%x\n", event);
	}

	static void detect_tablet_mode(struct platform_device *device)
	{
	const char *chassis_type = dmi_get_system_info(DMI_CHASSIS_TYPE);
	struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
	acpi_handle handle = ACPI_HANDLE(&device->dev);
	struct acpi_buffer vgbs_output = { ACPI_ALLOCATE_BUFFER, NULL };
	union acpi_object *obj;
	acpi_status status;
	int m;

	if (!(chassis_type && strcmp(chassis_type, "31") == 0))
	goto out;

	status = acpi_evaluate_object(handle, "VGBS", NULL, &vgbs_output);
	if (ACPI_FAILURE(status))
	goto out;

	obj = vgbs_output.pointer;
	if (!(obj && obj->type == ACPI_TYPE_INTEGER))
	goto out;

	m = !(obj->integer.value & TABLET_MODE_FLAG);
	input_report_switch(priv->input_dev, SW_TABLET_MODE, m);
	out:
	kfree(vgbs_output.pointer);
	}

	static int intel_vbtn_probe(struct platform_device *device)
	{
	acpi_handle handle = ACPI_HANDLE(&device->dev);
	struct intel_vbtn_priv *priv;
	acpi_status status;
	int err;

	status = acpi_evaluate_object(handle, "VBDL", NULL, NULL);
	if (ACPI_FAILURE(status)) {
	dev_warn(&device->dev, "failed to read Intel Virtual Button driver\n");
	return -ENODEV;
	}

	priv = devm_kzalloc(&device->dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
	return -ENOMEM;
	dev_set_drvdata(&device->dev, priv);

	err = intel_vbtn_input_setup(device);
	if (err) {
	pr_err("Failed to setup Intel Virtual Button\n");
	return err;
	}

	detect_tablet_mode(device);

	status = acpi_install_notify_handler(handle,
	ACPI_DEVICE_NOTIFY,
	notify_handler,
	device);
	if (ACPI_FAILURE(status))
	return -EBUSY;

	device_init_wakeup(&device->dev, true);
	return 0;
	}

	static int intel_vbtn_remove(struct platform_device *device)
	{
	acpi_handle handle = ACPI_HANDLE(&device->dev);

	device_init_wakeup(&device->dev, false);
	acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);

	/*
	* Even if we failed to shut off the event stream, we can still
	* safely detach from the device.
	*/
	return 0;
	}

	static int intel_vbtn_pm_prepare(struct device *dev)
	{
	struct intel_vbtn_priv *priv = dev_get_drvdata(dev);

	priv->wakeup_mode = true;
	return 0;
	}

	static int intel_vbtn_pm_resume(struct device *dev)
	{
	struct intel_vbtn_priv *priv = dev_get_drvdata(dev);

	priv->wakeup_mode = false;
	return 0;
	}

	static const struct dev_pm_ops intel_vbtn_pm_ops = {
	.prepare = intel_vbtn_pm_prepare,
	.resume = intel_vbtn_pm_resume,
	.restore = intel_vbtn_pm_resume,
	.thaw = intel_vbtn_pm_resume,
	};

	static struct platform_driver intel_vbtn_pl_driver = {
	.driver = {
	.name = "intel-vbtn",
	.acpi_match_table = intel_vbtn_ids,
	.pm = &intel_vbtn_pm_ops,
	},
	.probe = intel_vbtn_probe,
	.remove = intel_vbtn_remove,
	};
	MODULE_DEVICE_TABLE(acpi, intel_vbtn_ids);

	static acpi_status __init
	check_acpi_dev(acpi_handle handle, u32 lvl, void context, void *rv)
	{
	const struct acpi_device_id *ids = context;
	struct acpi_device *dev;

	if (acpi_bus_get_device(handle, &dev) != 0)
	return AE_OK;

	if (acpi_match_device_ids(dev, ids) == 0)
	if (acpi_create_platform_device(dev, NULL))
	dev_info(&dev->dev,
	"intel-vbtn: created platform device\n");

	return AE_OK;
	}

	static int __init intel_vbtn_init(void)
	{
	acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
	ACPI_UINT32_MAX, check_acpi_dev, NULL,
	(void *)intel_vbtn_ids, NULL);

	return platform_driver_register(&intel_vbtn_pl_driver);
	}
	module_init(intel_vbtn_init);

	static void __exit intel_vbtn_exit(void)
	{
	platform_driver_unregister(&intel_vbtn_pl_driver);
	}
	module_exit(intel_vbtn_exit);