On Wed, Dec 12, 2018 at 08:01:07AM +0000, Andrei.Stefanescu@xxxxxxxxxxxxx wrote: > > This puts the device into low power mode when the suspend function gets > > called but this might not be safe - devices using the regulator may not > > be suspended yet so could still need full regulation. Normally a GPIO > > triggered transition like this would be being done by hardware as part > > of the process of suspending the SoC. Is there some reason to do this > > manually? > There is a line from the MPU (SHDN) which goes low only when the MPU > turns off. That line is already connected to the PMIC and it differentiates > between suspend-to-mem and standby. To switch to low-power, the PMIC must > be controlled by the GPIO pin LPM. > The suspend sequence is: > - LPM pin goes high (PMIC enters Low-Power <-> Linux standby) > - SHDN goes low (if target suspend state is mem) and then PMIC enters > HIBERNATE This feels like it should be being controlled somewhere else, if it's actually causing a change in the PMIC state it seems like it wants to be done as late as possible in suspend to minimize the risks. At the very least suspend_late() for the driver seems appropriate. Could you submit a version with this feature at least split out into a separate patch please so we can apply the rest of the code while this is discussed?
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