Re: [PATCH 2/5] platform/x86: lg-laptop: Add support for native ACPI events

[Ilpo Järvinen]

On Mon, 22 Jun 2026, Armin Wolf wrote:

> LG devices support two interfaces for receiving events:
> - the WMI-based interface currently being used by the driver
> - a ACPI-based interface similar to the WMI-based interface
> 
> Older devices use the WMI-based interface by default and need
> to be manually switched into ACPI mode. Newer devices however
> only support the ACPI-based interface, preventing the current
> driver from receiving events on them.
> 
> Fix this by always using the native ACPI-based interface for
> receiving events.
> 
> Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
> ---
>  drivers/platform/x86/Kconfig     |   1 -
>  drivers/platform/x86/lg-laptop.c | 301 ++++++++++++++++++++-----------
>  2 files changed, 199 insertions(+), 103 deletions(-)
> 
> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
> index b54b5212b204..957034f39e4e 100644
> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -802,7 +802,6 @@ config LG_LAPTOP
>  	tristate "LG Laptop Extras"
>  	depends on ACPI
>  	depends on ACPI_BATTERY
> -	depends on ACPI_WMI
>  	depends on INPUT
>  	select INPUT_SPARSEKMAP
>  	select NEW_LEDS
> diff --git a/drivers/platform/x86/lg-laptop.c b/drivers/platform/x86/lg-laptop.c
> index a2db9657027e..ead0c3cc74a8 100644
> --- a/drivers/platform/x86/lg-laptop.c
> +++ b/drivers/platform/x86/lg-laptop.c
> @@ -57,13 +57,18 @@ MODULE_PARM_DESC(fw_debug, "Enable printing of firmware debug messages");
>  #define LG_ADDRESS_SPACE_DEBUG_MSG_START_ADR	0x3E8
>  #define LG_ADDRESS_SPACE_DEBUG_MSG_END_ADR	0x5E8
>  
> -#define WMI_EVENT_GUID0	"E4FB94F9-7F2B-4173-AD1A-CD1D95086248"
> -#define WMI_EVENT_GUID1	"023B133E-49D1-4E10-B313-698220140DC2"
> -#define WMI_EVENT_GUID2	"37BE1AC0-C3F2-4B1F-BFBE-8FDEAF2814D6"
> -#define WMI_EVENT_GUID3	"911BAD44-7DF8-4FBB-9319-BABA1C4B293B"
> -#define WMI_METHOD_WMAB "C3A72B38-D3EF-42D3-8CBB-D5A57049F66D"
> -#define WMI_METHOD_WMBB "2B4F501A-BD3C-4394-8DCF-00A7D2BC8210"
> -#define WMI_EVENT_GUID  WMI_EVENT_GUID0
> +#define LG_NOTIFY_TABLET_MODE_OFF	0x50
> +#define LG_NOTIFY_TABLET_MODE_ON	0x51
> +#define LG_NOTIFY_HOTKEY		0x80
> +#define LG_NOTIFY_THERMAL		0x81
> +#define LG_NOTIFY_MISC			0x82
> +
> +#define LG_OREP_READ_EC			0
> +#define LG_OREP_WRITE_EC		1
> +#define LG_OREP_DEBUG			2
> +#define LG_OREP_UPDATE_SYSTEM_STATE	3
> +#define LG_OREP_INTERCEPT_WMI_EVENTS	4
> +#define LG_OREP_WAKE_ON_LAN		6
>  
>  #define SB_GGOV_METHOD  "\\_SB.GGOV"
>  #define GOV_TLED        0x2020008
> @@ -83,21 +88,7 @@ MODULE_PARM_DESC(fw_debug, "Enable printing of firmware debug messages");
>  
>  #define PLATFORM_NAME   "lg-laptop"
>  
> -MODULE_ALIAS("wmi:" WMI_EVENT_GUID0);
> -MODULE_ALIAS("wmi:" WMI_EVENT_GUID1);
> -MODULE_ALIAS("wmi:" WMI_EVENT_GUID2);
> -MODULE_ALIAS("wmi:" WMI_EVENT_GUID3);
> -MODULE_ALIAS("wmi:" WMI_METHOD_WMAB);
> -MODULE_ALIAS("wmi:" WMI_METHOD_WMBB);
> -
>  static struct platform_device *pf_device;
> -static struct input_dev *wmi_input_dev;
> -
> -static u32 inited;
> -#define INIT_INPUT_WMI_0        0x01
> -#define INIT_INPUT_WMI_2        0x02
> -#define INIT_INPUT_ACPI         0x04
> -#define INIT_SPARSE_KEYMAP      0x80
>  
>  static int battery_limit_use_wmbb;
>  static bool kbd_backlight_available;
> @@ -115,6 +106,36 @@ static const struct key_entry wmi_keymap[] = {
>  	{KE_END, 0}
>  };
>  
> +static int lg_laptop_execute_orep(acpi_handle handle, u64 command, u64 value,
> +				  unsigned long long *result)
> +{
> +	union acpi_object objs[] = {
> +		{
> +			.integer = {
> +				.type = ACPI_TYPE_INTEGER,
> +				.value = command,
> +			},
> +		},
> +		{
> +			.integer = {
> +				.type = ACPI_TYPE_INTEGER,
> +				.value = value,
> +			},
> +		}
> +	};
> +	struct acpi_object_list args = {
> +		.count = ARRAY_SIZE(objs),
> +		.pointer = objs,
> +	};
> +	acpi_status status;
> +
> +	status = acpi_evaluate_integer(handle, "OREP", &args, result);
> +	if (ACPI_FAILURE(status))
> +		return -EIO;
> +
> +	return 0;
> +}
> +
>  static int ggov(u32 arg0)
>  {
>  	union acpi_object args[1];
> @@ -212,70 +233,6 @@ static union acpi_object *lg_wmbb(struct device *dev, u32 method_id, u32 arg1, u
>  	return (union acpi_object *)buffer.pointer;
>  }
>  
> -static void wmi_notify(union acpi_object *obj, void *context)
> -{
> -	long data = (long)context;
> -	unsigned int brightness;
> -
> -	pr_debug("event guid %li\n", data);
> -	if (!obj)
> -		return;
> -
> -	if (obj->type == ACPI_TYPE_INTEGER) {
> -		int eventcode = obj->integer.value;
> -		struct key_entry *key;
> -
> -		if (eventcode == 0x10000000) {
> -			if (kbd_backlight_available) {
> -				brightness = get_kbd_backlight_level(kbd_backlight.dev->parent);
> -				led_classdev_notify_brightness_hw_changed(&kbd_backlight,
> -									  brightness);
> -			}
> -		} else {
> -			key = sparse_keymap_entry_from_scancode(
> -				wmi_input_dev, eventcode);
> -			if (key && key->type == KE_KEY)
> -				sparse_keymap_report_entry(wmi_input_dev,
> -							   key, 1, true);
> -		}
> -	}
> -
> -	pr_debug("Type: %i    Eventcode: 0x%llx\n", obj->type,
> -		 obj->integer.value);
> -}
> -
> -static void wmi_input_setup(void)
> -{
> -	acpi_status status;
> -
> -	wmi_input_dev = input_allocate_device();
> -	if (wmi_input_dev) {
> -		wmi_input_dev->name = "LG WMI hotkeys";
> -		wmi_input_dev->phys = "wmi/input0";
> -		wmi_input_dev->id.bustype = BUS_HOST;
> -
> -		if (sparse_keymap_setup(wmi_input_dev, wmi_keymap, NULL) ||
> -		    input_register_device(wmi_input_dev)) {
> -			pr_info("Cannot initialize input device");
> -			input_free_device(wmi_input_dev);
> -			return;
> -		}
> -
> -		inited |= INIT_SPARSE_KEYMAP;
> -		status = wmi_install_notify_handler(WMI_EVENT_GUID0, wmi_notify,
> -						    (void *)0);
> -		if (ACPI_SUCCESS(status))
> -			inited |= INIT_INPUT_WMI_0;
> -
> -		status = wmi_install_notify_handler(WMI_EVENT_GUID2, wmi_notify,
> -						    (void *)2);
> -		if (ACPI_SUCCESS(status))
> -			inited |= INIT_INPUT_WMI_2;
> -	} else {
> -		pr_info("Cannot allocate input device");
> -	}
> -}
> -
>  static ssize_t fan_mode_store(struct device *dev,
>  			      struct device_attribute *attr,
>  			      const char *buffer, size_t count)
> @@ -634,26 +591,164 @@ static enum led_brightness kbd_backlight_get(struct led_classdev *cdev)
>  
>  static LED_DEVICE(kbd_backlight, 255, LED_BRIGHT_HW_CHANGED);
>  
> -static void wmi_input_destroy(void)
> +static struct platform_driver pf_driver = {
> +	.driver = {
> +		   .name = PLATFORM_NAME,
> +	}
> +};
> +
> +static int lg_laptop_get_event_data(acpi_handle handle, u32 value, u32 *data)
>  {
> -	if (inited & INIT_INPUT_WMI_2)
> -		wmi_remove_notify_handler(WMI_EVENT_GUID2);
> +	union acpi_object objs[] = {
> +		{
> +			.integer = {
> +				.type = ACPI_TYPE_INTEGER,
> +				.value = value,
> +			},
> +		}
> +	};
> +	struct acpi_object_list args = {
> +		.count = ARRAY_SIZE(objs),

Add the include.

> +		.pointer = objs,
> +	};
> +	unsigned long long result;
> +	acpi_status status;
> +
> +	status = acpi_evaluate_integer(handle, "_WED", &args, &result);
> +	if (ACPI_FAILURE(status))
> +		return -EIO;
>  
> -	if (inited & INIT_INPUT_WMI_0)
> -		wmi_remove_notify_handler(WMI_EVENT_GUID0);
> +	if (result > U32_MAX)

Add include.

> +		return -EPROTO;
>  
> -	if (inited & INIT_SPARSE_KEYMAP)
> -		input_unregister_device(wmi_input_dev);
> +	*data = result;
>  
> -	inited &= ~(INIT_INPUT_WMI_0 | INIT_INPUT_WMI_2 | INIT_SPARSE_KEYMAP);
> +	return 0;
>  }
>  
> -static struct platform_driver pf_driver = {
> -	.driver = {
> -		   .name = PLATFORM_NAME,
> +static void lg_laptop_handle_input_event(struct input_dev *input_dev, u32 value, u32 data)
> +{
> +	unsigned int kbd_brightness;
> +
> +	switch (value) {
> +	case LG_NOTIFY_HOTKEY:
> +		sparse_keymap_report_event(input_dev, data, 1, true);
> +		break;
> +	case LG_NOTIFY_THERMAL:
> +		/* Currently not supported */
> +		break;
> +	case LG_NOTIFY_MISC:
> +		switch (data) {
> +		case 0x10000000:
> +			if (!kbd_backlight_available)
> +				break;
> +
> +			kbd_brightness = get_kbd_backlight_level(kbd_backlight.dev->parent);
> +			led_classdev_notify_brightness_hw_changed(&kbd_backlight, kbd_brightness);
> +			break;
> +		default:
> +			sparse_keymap_report_event(input_dev, data, 1, true);
> +		}
> +		break;
> +	default:
> +		break;
> +	}
> +}
> +
> +static void lg_laptop_notify_handler(acpi_handle handle, u32 value, void *context)
> +{
> +	struct input_dev *input_dev = context;
> +	u32 data;
> +	int ret;
> +
> +	switch (value) {
> +	case LG_NOTIFY_TABLET_MODE_OFF:
> +	case LG_NOTIFY_TABLET_MODE_ON:
> +		/* Already handled by intel-hid */
> +		return;
> +	case LG_NOTIFY_HOTKEY:
> +	case LG_NOTIFY_THERMAL:
> +	case LG_NOTIFY_MISC:
> +		ret = lg_laptop_get_event_data(handle, value, &data);
> +		if (ret < 0) {
> +			dev_notice(input_dev->dev.parent, "Failed to get event data: %d\n", ret);
> +			return;
> +		}
> +
> +		dev_dbg(input_dev->dev.parent, "Received event %u (%u)\n", value, data);
> +
> +		lg_laptop_handle_input_event(input_dev, value, data);
> +		return;
> +	default:
> +		dev_notice(input_dev->dev.parent, "Received unknown event %u\n", value);
>  	}
>  };
>  
> +static void lg_laptop_remove_notify_handler(void *context)
> +{
> +	acpi_handle handle = context;
> +
> +	acpi_remove_notify_handler(handle, ACPI_ALL_NOTIFY, lg_laptop_notify_handler);
> +}
> +
> +static void lg_laptop_reenable_wmi_events(void *context)
> +{
> +	acpi_handle handle = context;
> +	unsigned long long dummy;
> +
> +	lg_laptop_execute_orep(handle, LG_OREP_INTERCEPT_WMI_EVENTS, 0, &dummy);
> +}
> +
> +static int lg_laptop_input_init(struct device *dev, acpi_handle handle)
> +{
> +	struct input_dev *input_dev;
> +	unsigned long long result;
> +	acpi_status status;
> +	int ret;
> +
> +	if (!acpi_has_method(handle, "_WED"))
> +		return 0;
> +
> +	input_dev = devm_input_allocate_device(dev);
> +	if (!input_dev)
> +		return -ENOMEM;
> +
> +	input_dev->name = "LG WMI hotkeys";
> +	input_dev->phys = "wmi/input0";
> +	input_dev->id.bustype = BUS_HOST;
> +	ret = sparse_keymap_setup(input_dev, wmi_keymap, NULL);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = input_register_device(input_dev);
> +	if (ret < 0)
> +		return ret;
> +
> +	status = acpi_install_notify_handler(handle, ACPI_ALL_NOTIFY, lg_laptop_notify_handler,
> +					     input_dev);
> +	if (ACPI_FAILURE(status))
> +		return -EIO;
> +
> +	ret = devm_add_action_or_reset(dev, lg_laptop_remove_notify_handler, handle);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (acpi_has_method(handle, "OREP")) {
> +		ret = lg_laptop_execute_orep(handle, LG_OREP_INTERCEPT_WMI_EVENTS, 1, &result);
> +		if (ret < 0)
> +			return ret;
> +
> +		if (result)

This still looks to be part of the error handling so please remove the 
blank line before it.

> +			return -EIO;
> +
> +		ret = devm_add_action_or_reset(dev, lg_laptop_reenable_wmi_events, handle);
> +		if (ret < 0)
> +			return ret;
> +	}
> +
> +	return 0;
> +}
> +
>  static acpi_status lg_laptop_address_space_write(struct device *dev, acpi_physical_address address,
>  						 size_t size, u64 value)
>  {
> @@ -865,10 +960,6 @@ static int acpi_probe(struct platform_device *pdev)
>  	if (year >= 2019)
>  		battery_limit_use_wmbb = 1;
>  
> -	ret = sysfs_create_group(&pf_device->dev.kobj, &dev_attribute_group);
> -	if (ret)
> -		goto out_platform_device;
> -
>  	/* LEDs are optional */
>  	ret = devm_led_classdev_register(&pdev->dev, &kbd_backlight);
>  	if (ret < 0)
> @@ -878,7 +969,14 @@ static int acpi_probe(struct platform_device *pdev)
>  
>  	devm_led_classdev_register(&pdev->dev, &tpad_led);
>  
> -	wmi_input_setup();
> +	ret = lg_laptop_input_init(&pdev->dev, device->handle);
> +	if (ret < 0)
> +		goto out_platform_device;
> +
> +	ret = sysfs_create_group(&pf_device->dev.kobj, &dev_attribute_group);
> +	if (ret)
> +		goto out_platform_device;

Not directly related to the patch, but can't .dev_groups be used?

>  	battery_hook_register(&battery_hook);
>  
>  	return 0;
> @@ -895,7 +993,6 @@ static void acpi_remove(struct platform_device *pdev)
>  	sysfs_remove_group(&pf_device->dev.kobj, &dev_attribute_group);
>  
>  	battery_hook_unregister(&battery_hook);
> -	wmi_input_destroy();
>  	platform_device_unregister(pf_device);
>  	pf_device = NULL;
>  	platform_driver_unregister(&pf_driver);
> 

-- 
 i.