On Mon, 31 Mar 2025 at 10:21, Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx> wrote: > > > > > +static bool mmc_may_poweroff_notify(const struct mmc_host *host, > > > + bool is_suspend) > > Maybe add some comments about the difference between > mmc_can_poweroff_notify() and mmc_may_poweroff_notify()? Like make it > super-obvious, so I will easily remember next year again :) mmc_can_* functions are mostly about checking what the card is capable of. So mmc_can_poweroff_notify() should be consistent with the other similar functions. For eMMC power-off notifications in particular, it has become more complicated as we need to check the power-off scenario along with the host's capabilities, to understand what we should do. I am certainly open to another name than mmc_may_power_off_notify(), if that is what you are suggesting. Do you have a proposal? :-) > > > > if (mmc_can_poweroff_notify(host->card) && > > > - !(host->caps2 & MMC_CAP2_FULL_PWR_CYCLE)) > > > + !mmc_may_poweroff_notify(host, true)) > > I guess this deserve some extra documentation because: > > If MMC_CAP2_FULL_PWR_CYCLE is not set but MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND is set, > > !mmc_may_poweroff_notify(host, true) will evaluate to false while !(host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) will evaluate to true. Right. See more below. > > I agree, I neither get this. Another way to express my confusion is: Why > do we set the 'is_suspend' flag to true in the shutdown function? > I understand your concern and I agree that this is rather messy. Anyway, for shutdown, we set the is_suspend flag to false. The reasoning behind this is that during shutdown we know that the card will be fully powered-down (both vcc and vccq will be cut). In suspend/runtime_suspend, we don't really know as it depends on what the platform/host is capable of. If we can't do a full power-off (maybe just vcc can be cut), then we prefer the sleep command instead. I was hoping that patch3 should make this more clear (using an enum type), but I can try to add some comment(s) in the code to further clarify the policy. Thanks for reviewing and testing! Kind regards Uffe
