Hi, On 08/05/2020 13:02:26+0200, Thierry Reding wrote: > On Fri, May 01, 2020 at 03:53:09PM +0200, Alexandre Belloni wrote: > > On 01/05/2020 08:00:11-0500, Rob Herring wrote: > > > > I don't think this is true because in the case of a discrete RTC, its > > > > interrupt pin can be connected directly to a PMIC to power up a board > > > > instead of being connected to the SoC. In that case we don't have an > > > > interrupt property but the RTC is still a wakeup source. This is the > > > > usual use case for wakeup-source in the RTC subsystem. Else, if there is > > > > an interrupt, then we assume the RTC is a wakeup source and there is no > > > > need to have the wakeup-source property. > > > > > > Yes, that would be an example of "unless the wakeup mechanism is > > > somehow not an interrupt". I guess I should add not an interrupt from > > > the perspective of the OS. > > > > > > So if the wakeup is self contained within the PMIC, why do we need a > > > DT property? The capability is always there and enabling/disabling > > > wakeup from it is userspace policy. > > > > > > > Yes, for this particular case, I'm not sure wakeup-source is actually > > necessary. If the interrupt line is used to wakeup the SoC, then the > > presence of the interrupts property is enough to enable wakeup. > > So yes, the wakeup-source property isn't necessary. The goal of patches > 1 and 2 was to allow the RTC to be actually disabled as a wakeup-source > in case it didn't work as intended. But since the RTC is enabled as a > wakeup source on these PMICs by default, the idea was to add a new sub- > node for the RTC and required the wakeup-source in that subnode if that > subnode was present. > > That said, patch 3 actually does make the RTC work as a wakeup source > on the particular board that I tested this, so patches 1 and 2 are no > longer really required from my point of view. > > Do you want me to send patch 3/3 again separately or can you pick it up > from this series? > I applied it. -- Alexandre Belloni, Bootlin Embedded Linux and Kernel engineering https://bootlin.com
