Re: [PATCH v3] Input: rename INPUT_PROP_HAPTIC_TOUCHPAD to INPUT_PROP_PRESSUREPAD

From: Dmitry Torokhov
Date: Tue Nov 18 2025 - 02:42:16 EST


On Thu, Nov 06, 2025 at 09:45:34PM +1000, Peter Hutterer wrote:
> And expand it to encompass all pressure pads.
>
> Definition: "pressure pad" as used here as includes all touchpads that
> use physical pressure to convert to click, without physical hinges. Also
> called haptic touchpads in general parlance, Synaptics calls them
> ForcePads.
>
> Most (all?) pressure pads are currently advertised as
> INPUT_PROP_BUTTONPAD. The suggestion to identify them as pressure pads
> by defining the resolution on ABS_MT_PRESSURE has been in the docs since
> commit 20ccc8dd38a3 ("Documentation: input: define
> ABS_PRESSURE/ABS_MT_PRESSURE resolution as grams") but few devices
> provide this information.
>
> In userspace it's thus impossible to determine whether a device is a
> true pressure pad (pressure equals pressure) or a normal clickpad with
> (pressure equals finger size).
>
> Commit 7075ae4ac9db ("Input: add INPUT_PROP_HAPTIC_TOUCHPAD") introduces
> INPUT_PROP_HAPTIC_TOUCHPAD but restricted it to those touchpads that
> have support for userspace-controlled effects. Let's expand and rename
> that definition to include all pressure pad touchpads since those that
> do support FF effects can be identified by the presence of the
> FF_HAPTIC bit.
>
> This means:
> - clickpad: INPUT_PROP_BUTTONPAD
> - pressurepad: INPUT_PROP_BUTTONPAD + INPUT_PROP_PRESSUREPAD
> - pressurepad with configurable haptics:
> INPUT_PROP_BUTTONPAD + INPUT_PROP_PRESSUREPAD + FF_HAPTIC
>
> Signed-off-by: Peter Hutterer <peter.hutterer@xxxxxxxxx>

Applied, thank you.

--
Dmitry