Re: [PATCH] platform/x86/hp/hp-wmi: Add periodic tablet mode poll

["Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>]

On Wed, 12 Aug 2026, nicourced@altlinux.org wrote:

> From: Ilya Mukhamadeev <nicourced@altlinux.org>
> 
> Some HP convertible laptops (e.g., ProBook x360 series) do not generate
> ACPI events when switching between laptop and tablet mode, causing the
> input subsystem to never receive SW_TABLET_MODE notifications.
> 
> Add a periodic delayed work that polls the tablet mode state every
> second and reports changes via input_report_switch(). Track the last
> known state to avoid sending duplicate events, and clean up the work
> queue on module removal.
> ---
>  drivers/platform/x86/hp/hp-wmi.c | 35 +++++++++++++++++++++++++++++---
>  1 file changed, 32 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/platform/x86/hp/hp-wmi.c b/drivers/platform/x86/hp/hp-wmi.c
> index 8ba286ed8721..5fbfdde3291a 100644
> --- a/drivers/platform/x86/hp/hp-wmi.c
> +++ b/drivers/platform/x86/hp/hp-wmi.c
> @@ -460,6 +460,8 @@ static struct notifier_block platform_power_source_nb;
>  static enum platform_profile_option active_platform_profile;
>  static bool platform_profile_support;
>  static bool zero_insize_support;
> +static int last_tablet_state = -1;
> +static struct delayed_work tablet_mode_work;
>  
>  static struct rfkill *wifi_rfkill;
>  static struct rfkill *bluetooth_rfkill;
> @@ -1176,9 +1178,13 @@ static void hp_wmi_notify(union acpi_object *obj, void *context)
>  		if (test_bit(SW_DOCK, hp_wmi_input_dev->swbit))
>  			input_report_switch(hp_wmi_input_dev, SW_DOCK,
>  					    hp_wmi_get_dock_state());
> -		if (test_bit(SW_TABLET_MODE, hp_wmi_input_dev->swbit))
> -			input_report_switch(hp_wmi_input_dev, SW_TABLET_MODE,
> -					    hp_wmi_get_tablet_mode());
> +		if (test_bit(SW_TABLET_MODE, hp_wmi_input_dev->swbit)) {
> +			int tablet = hp_wmi_get_tablet_mode();
> +			if (tablet >= 0) {
> +				last_tablet_state = tablet;

Couldn't this just remove the work when we've positive confirmation the 
events work?

--
 i.

> +				input_report_switch(hp_wmi_input_dev, SW_TABLET_MODE, tablet);
> +			}
> +		}
>  		input_sync(hp_wmi_input_dev);
>  		break;
>  	case HPWMI_PARK_HDD:
> @@ -1271,6 +1277,24 @@ static void hp_wmi_notify(union acpi_object *obj, void *context)
>  	}
>  }
>  
> +/*
> + * Periodically poll tablet mode state and send input events if changed.
> + * This works around missing ACPI events on some HP laptops.
> + */
> +static void hp_wmi_tablet_mode_work_handler(struct work_struct *work)
> +{
> +	int cur = hp_wmi_get_tablet_mode();
> +	if (cur >= 0 && cur != last_tablet_state) {
> +		last_tablet_state = cur;
> +		if (hp_wmi_input_dev && test_bit(SW_TABLET_MODE, hp_wmi_input_dev->swbit)) {
> +			input_report_switch(hp_wmi_input_dev, SW_TABLET_MODE, cur);
> +			input_sync(hp_wmi_input_dev);
> +			pr_debug("Tablet mode changed to %d\n", cur);
> +		}
> +	}
> +	schedule_delayed_work(&tablet_mode_work, msecs_to_jiffies(1000));
> +}
> +
>  static int __init hp_wmi_input_setup(void)
>  {
>  	acpi_status status;
> @@ -1298,6 +1322,9 @@ static int __init hp_wmi_input_setup(void)
>  	if (!(val < 0)) {
>  		__set_bit(SW_TABLET_MODE, hp_wmi_input_dev->swbit);
>  		input_report_switch(hp_wmi_input_dev, SW_TABLET_MODE, val);
> +		last_tablet_state = val;
> +		INIT_DELAYED_WORK(&tablet_mode_work, hp_wmi_tablet_mode_work_handler);
> +		schedule_delayed_work(&tablet_mode_work, msecs_to_jiffies(1000));
>  	}
>  
>  	err = sparse_keymap_setup(hp_wmi_input_dev, hp_wmi_keymap, NULL);
> @@ -1331,6 +1358,8 @@ static int __init hp_wmi_input_setup(void)
>  
>  static void hp_wmi_input_destroy(void)
>  {
> +	cancel_delayed_work_sync(&tablet_mode_work);
> +	last_tablet_state = -1;
>  	wmi_remove_notify_handler(HPWMI_EVENT_GUID);
>  	input_unregister_device(hp_wmi_input_dev);
>  }
> 

-- 
 i.