Re: [PATCH 1/2] Input: Add a helper for reporting a screen lock key sequence

[Armin Wolf <W_Armin@gmx.de>]

Am 07.04.25 um 17:27 schrieb Mario Limonciello:

> From: Mario Limonciello <mario.limonciello@amd.com>
>
> In the PC industry KEY_SCREENLOCK isn't used as frequently as it used
> to be. Modern versions of Windows [1], GNOME and KDE support "META" + "L"
> to lock the screen. Modern hardware [2] also sends this sequence of
> events for keys with a silkscreen for screen lock.
>
> Introduced a helper input_report_lock_sequence() for drivers to utilize
> if they want to send this sequence.
>
> Link: https://support.microsoft.com/en-us/windows/keyboard-shortcuts-in-windows-dcc61a57-8ff0-cffe-9796-cb9706c75eec [1]
> Link: https://www.logitech.com/en-us/shop/p/k860-split-ergonomic.920-009166 [2]
> Suggested-by: Armin Wolf <W_Armin@gmx.de>
> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
> ---
>   drivers/input/input.c | 20 ++++++++++++++++++++
>   include/linux/input.h |  2 ++
>   2 files changed, 22 insertions(+)
>
> diff --git a/drivers/input/input.c b/drivers/input/input.c
> index ec4346f20efdd..dfeace85c4710 100644
> --- a/drivers/input/input.c
> +++ b/drivers/input/input.c
> @@ -508,6 +508,26 @@ void input_copy_abs(struct input_dev *dst, unsigned int dst_axis,
>   }
>   EXPORT_SYMBOL(input_copy_abs);
>   
> +/**
> + * input_report_lock_sequence - Report key combination to lock the screen
> + * @dev: input device
> + *
> + * Key combination used in the PC industry since Windows 7 for locking display
> + * is META + L. This is also used in GNOME and KDE by default.
> + * See https://support.microsoft.com/en-us/windows/keyboard-shortcuts-in-windows-dcc61a57-8ff0-cffe-9796-cb9706c75eec
> + */

Hi,

maybe it would make more sense to have the input subsystem transparently translate between KEY_SCREENLOCK and this
special screen lock sequence. This way there would be no room for regressions as people could enable/disable this
behavior via Kconfig.

Thanks,
Armin Wolf

> +void input_report_lock_sequence(struct input_dev *dev)
> +{
> +	input_report_key(dev, KEY_LEFTMETA, 1);
> +	input_report_key(dev, KEY_L, 1);
> +	input_sync(dev);
> +	input_report_key(dev, KEY_L, 0);
> +	input_sync(dev);
> +	input_report_key(dev, KEY_LEFTMETA, 0);
> +	input_sync(dev);
> +}
> +EXPORT_SYMBOL(input_report_lock_sequence);
> +
>   /**
>    * input_grab_device - grabs device for exclusive use
>    * @handle: input handle that wants to own the device
> diff --git a/include/linux/input.h b/include/linux/input.h
> index 7d7cb0593a63e..16f7bef12f1c1 100644
> --- a/include/linux/input.h
> +++ b/include/linux/input.h
> @@ -492,6 +492,8 @@ void input_set_abs_params(struct input_dev *dev, unsigned int axis,
>   void input_copy_abs(struct input_dev *dst, unsigned int dst_axis,
>   		    const struct input_dev *src, unsigned int src_axis);
>   
> +void input_report_lock_sequence(struct input_dev *dev);
> +
>   #define INPUT_GENERATE_ABS_ACCESSORS(_suffix, _item)			\
>   static inline int input_abs_get_##_suffix(struct input_dev *dev,	\
>   					  unsigned int axis)		\