Re: [PATCH 01/13] PM: Add wake lock api.

Pavel Machek
2009-02-10T20:25:07Z

On Thu 2009-02-05 16:13:27, Arve Hj?nnev?g wrote:
> On Thu, Feb 5, 2009 at 2:51 PM, mark gross <mgross@linux.intel.com> wrote:
> >> +A locked wakelock, depending on its type, prevents the system from entering
> >> +suspend or other low-power states. When creating a wakelock, you can select
> >> +if it prevents suspend or low-power idle states. If the type is set to
> >> +WAKE_LOCK_SUSPEND, the wakelock prevents a full system suspend. If the type
> >> +is WAKE_LOCK_IDLE, low-power states that cause large interrupt latencies, or
> >> +that disable a set of interrupts, will not be entered from idle until the
> >> +wakelocks are released. Unless the type is specified, this document refers
> >> +to wakelocks with the type set to WAKE_LOCK_SUSPEND.
> >
> > How much of this can be implemented using a pm-qos approach?
>
> WAKE_LOCK_IDLE overlaps with pm-qos, if you use it to prevent latency.

Yes. So pleaase remove wake_lock_idle and use pm-qos. Feel free to
improve pm-qos if you need to.

> > wake_lock going to block until the dives its locking is in a good power
> > state? (I'm guessing yes) Is doing this in the context of and IRQ a
> > good idea?
>
> wake_lock never blocks.

Wakelock is really bad name: it is not a lock and it does not protect
wake. I'd say we need better name here.
--

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