On Mon, Apr 23, 2018 at 11:32 AM, Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote: > Hi Rafael, > > On Mon, Apr 23, 2018 at 11:18 AM, Rafael J. Wysocki <rjw@xxxxxxxxxxxxx> wrote: >> On Wednesday, March 14, 2018 12:26:24 PM CEST Geert Uytterhoeven wrote: >>> Add a callback to inform a device that his wake-up setting has been >>> changed. This allows a device to synchronize device configuration with >>> an external user action. >>> >>> E.g. on systems using a Rohm BD9571MWV PMIC and a toggle accessory power >>> switch, the system suspend procedure is: >>> 1. Configure PMIC for DDR backup mode, which changes the role of the >>> accessory power switch from a power to a wake-up switch, >>> 2. Switch accessory power switch off, to prepare for system suspend, >>> 3. Suspend system. >>> >>> Hence step 1 cannot be done in the PMIC's suspend callback, >> >> I don't quite understand this, so can you please explain? >> >> What can't it be done from ->prepare() or even from a suspend notifier? >> >>> but it can be done in the new callback, in response to the user writing "enabled" >>> to the PMIC's wakeup virtual file in sysfs. > > Step 2 (flip a switch on the board) is a manual step, to be done by the user. > So it cannot be done from any suspend callback or notifier. I still find it somewhat difficult to follow you here. :-) How is this expected to work? Is the user expected to flip the switch on the board and then write to "wakeup" or is that the other way around?
