On Fri, May 04, 2018 at 02:04:15PM +0200, H. Nikolaus Schaller wrote: > It should be possible to cover this by a timer that is started > in this case. If there is serdev data received after assuming the module > is turned off, the driver has detected the wrong case - and can safely > close the serdev until we want to have it powered on again. > > If there is no response after turing off, the module power state is already > in sync and we can close the serdev as well - after the timeout (let's say > 30 seconds). Then, the serdev UART can idle. We should open the serdev > and start this timer also in the probe function to catch an initially wrong > state. Right, the only thing that worried me about that was that we cannot really delay system suspend for 30 seconds even if a somewhat shorter delay should be probably be sufficient (still a number of seconds). Configuring the serial controller as a wakeup source which aborts suspend or resumes if the driver gets it wrong might be preferred to draining the battery in suspend however. Johan -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
