Re: [PATCH] Input: da7280 - do not advertise FF_GAIN

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Mon, Nov 09, 2026 at 07:15:55PM +0200, Ivan Verbovoy via B4 Relay wrote:
> From: Ivan Verbovoy <ivanverbovoy@gmail.com>
> 
> The driver sets FF_GAIN in the device's force feedback capabilities but
> provides no set_gain() callback. input_ff_event() checks the capability
> bit, not the callback, before calling ff->set_gain(), so an EV_FF/FF_GAIN
> event written to the event node by any process with write access to it
> calls through a NULL pointer.
> 
> The driver has no global gain to set: a constant effect carries its own
> level, and a periodic effect plays a pattern from the device's waveform
> memory. Drop FF_GAIN from the capabilities, so that input_ff_event()
> ignores such an event.
> 
> Fixes: cd3f609823a5 ("Input: new da7280 haptic driver")
> Cc: stable@vger.kernel.org
> Signed-off-by: Ivan Verbovoy <ivanverbovoy@gmail.com>

Applied, thank you.

-- 
Dmitry