On Wed, Sep 13, 2017 at 2:34 PM, Pavel Machek <pa...@ucw.cz> wrote: > > On Wed 2017-09-13 14:20:58, David Lin wrote: > > On Wed, Sep 13, 2017 at 1:20 PM, Pavel Machek <pa...@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. > > I also thought we are over with that discussion. > > Yes, I'm working on fixing the docs. > > What mainline users are doing that?
Please refer to patch: https://patchwork.kernel.org/patch/8664831/ and https://android.googlesource.com/platform%2Fhardware%2Flibhardware/+/61701df363310a5cbd95e3e1638baa9526e42c9b I don't think currently there are drivers in the mainline using it yet, the reason being most of the Android devices are still on 4.4 kernel which still uses the legacy timed_output device. -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
