Re: [PATCH v4 1/2] Input: Add a Kconfig to emulate KEY_SCREENLOCK with META + L

[Mario Limonciello]

On 4/26/25 03:15, Pavel Machek wrote:
> On Fri 2025-04-25 11:29:48, Mario Limonciello wrote:
> > From: Mario Limonciello <mario.limonciello@xxxxxxx>
> >
> > 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 new Kconfig option that will change KEY_SCREENLOCK when
> > emitted by driver to META + L.
>
> Fix gnome and kde, do not break kernel...

I'm sorry; fix them to do what exactly?  Switch to KEY_SCREENLOCK?

That's going to break modern hardware lockscreen keys.  They've all 
obviously moved to META+L because that's what hardware today uses.

That's also what earlier versions of my series tried to change just 
amd-pmf over to use, but Armin Wolf said this should be done in the 
input subsystem for all drivers instead.

> 									Pavel
>
> >   
> > +config INPUT_SCREENLOCK_EMULATION
> > +	bool "Pass KEY_SCREENLOCK as META + L"
> > +	help
> > +	  Say Y here if you want KEY_SCREENLOCK to be passed to userspace as
> > +	  META + L.
> > +
> > +	  If unsure, say Y.
> > +
> >   comment "Input Device Drivers"
> >   
> >   source "drivers/input/keyboard/Kconfig"
> > diff --git a/drivers/input/input.c b/drivers/input/input.c
> > index dfeace85c4710..983e3c0f88e5f 100644
> > --- a/drivers/input/input.c
> > +++ b/drivers/input/input.c
> > @@ -370,6 +370,13 @@ void input_handle_event(struct input_dev *dev,
> >   	}
> >   }
> >   
> > +static void handle_screenlock_as_meta_l(struct input_dev *dev, unsigned int type,
> > +					int value)
> > +{
> > +	input_handle_event(dev, type, KEY_LEFTMETA, value);
> > +	input_handle_event(dev, type, KEY_L, value);
> > +}
> > +
> >   /**
> >    * input_event() - report new input event
> >    * @dev: device that generated the event
> > @@ -392,6 +399,12 @@ void input_event(struct input_dev *dev,
> >   {
> >   	if (is_event_supported(type, dev->evbit, EV_MAX)) {
> >   		guard(spinlock_irqsave)(&dev->event_lock);
> > +#ifdef CONFIG_INPUT_SCREENLOCK_EMULATION
> > +		if (code == KEY_SCREENLOCK) {
> > +			handle_screenlock_as_meta_l(dev, type, value);
> > +			return;
> > +		}
> > +#endif
> >   		input_handle_event(dev, type, code, value);
> >   	}
> >   }
> > @@ -2134,6 +2147,13 @@ void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int
> >   
> >   	switch (type) {
> >   	case EV_KEY:
> > +#ifdef CONFIG_INPUT_SCREENLOCK_EMULATION
> > +		if (code == KEY_SCREENLOCK) {
> > +			__set_bit(KEY_L, dev->keybit);
> > +			__set_bit(KEY_LEFTMETA, dev->keybit);
> > +			break;
> > +		}
> > +#endif
> >   		__set_bit(code, dev->keybit);
> >   		break;
> >