On Wed, Jan 14, 2009 at 1:09 AM, Nigel Cunningham <ncunningham@xxxxxxxxxxx> wrote: >> +/* A wake_lock prevents the system from entering suspend or other low power >> + * states when active. If the type is set to WAKE_LOCK_SUSPEND, the wake_lock >> + * prevents a full system suspend. If the type is WAKE_LOCK_IDLE, low power > > Does this include hibernation? If so, you might like to say 'sleep' > instead of suspend. > Not as it is currently implemented, but it probably should. The main reason I avoid saying 'sleep' is that we enter cpu sleep modes from idle as well. >> + * states that cause large interrupt latencies or that disable a set of >> + * interrupts will not entered from idle until the wake_locks are released. > > This makes me wonder if 'wake_locks' is an appropriate name - you're > locking against sleeping rather than waking. > It depends on how you look at it. We lock the system in the wake state, or we lock against the suspend/sleep state. I have also seen the term sleep vote used for a very similar mechanism, but I don't like this either as a sleep vote is a veto against sleep. I initially called it a suspend lock, then wake lock in user space. Wake lock is the term that stuck so I changed the kernel api to use it. > > If CONFIG_HAS_WAKELOCK and CONFIG_WAKELOCK_STAT are both off, you've got > an empty struct wake_lock definition. It wouldn't have any users, would > it? (And therefore doesn't need to be defined at all). > I do this to avoid #ifdefs on CONFIG_HAS_WAKELOCK in the drivers. >> +/* wake_lock_active returns a non-zero value if the wake_lock is currently >> + * locked. If the wake_lock has a timeout, it does not check the timeout >> + * but if the timeout had aready been checked it will return 0. > > s/aready/already/ > > What does it mean for the timeout to already have been checked? Is that > the same as the timeout having already expired? > What I meant was that the wake lock had been checked and deactivated from another code-path, after the timeout expired. -- Arve Hjønnevåg _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
