Re: [PATCH v2 0/3] led: ledtrig-transient: add support for hrtimer

David Lin
2017-09-13T21:20:58Z

On Wed, Sep 13, 2017 at 1:20 PM, Pavel Machek <pavel@ucw.cz> wrote:
>
> Hi!
>
> > These patch series add the LED_BRIGHTNESS_FAST flag support for
> > ledtrig-transient to use hrtimer so that platforms with high-resolution timer
> > support can have better accuracy in the trigger duration timing. The need for
> > this support is driven by the fact that Android has removed the timed_ouput [1]
> > and is now using led-trigger for handling vibrator control which requires the
> > timer to be accurate up to a millisecond. However, this flag support would also
> > allow hrtimer to co-exist with the ktimer without causing warning to the
> > existing drivers [2].
>
> NAK.
>
> LEDs do not need extra overhead, and vibrator control should not go
> through LED subsystem.
>
> Input subsystem includes support for vibrations and force
> feedback. Please use that instead.

I thought we are already over this discussion. As of now, the support
of vibrator through ledtrig is documented
(Documentation/leds/ledtrig-transient.txt) and there are users using
it.