Woot! On Thu, 2017-08-10 at 16:24 -0700, Srinivas Pandruvada wrote: > It has been reported for a while that with iio-sensor-proxy service the > rotation only works after one suspend/resume cycle. This required a wait > in the systemd unit file to avoid race. I found a Yoga 900 where I could > reproduce this. > > The problem scenerio is: > - During sensor driver init, enable run time PM and also set a > auto-suspend for 3 seconds. > This result in one runtime resume. But there is a check to avoid > a powerup in this sequence, but rpm is active > - User space iio-sensor-proxy tries to power up the sensor. Since rpm is > active it will simply return. But sensors were not actually > powered up in the prior sequence, so actaully the sensors will not work > - After 3 seconds the auto suspend kicks > > If we add a wait in systemd service file to fire iio-sensor-proxy after > 3 seconds, then now everything will work as the runtime resume will > actually powerup the sensor as this is a user request. > > To avoid this: > - Remove the check to match user requested state, this will cause a > brief powerup, but if the iio-sensor-proxy starts immediately it will > still work as the sensors are ON. > - Also move the autosuspend delay to place when user requested turn off > of sensors, like after user finished raw read or buffer disable > > Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx> Tested-by: Bastien Nocera <hadess@xxxxxxxxxx> I'm still chasing a couple of bugs in the user-space side of things caused by the removal of the timeout. Thanks! -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
