Re: [Update][PATCH 6/10] PM / Domains: System-wide transitions support for generic domains (v5)

From: Kevin Hilman
Date: Thu Jul 07 2011 - 20:29:45 EST


"Rafael J. Wysocki" <rjw@xxxxxxx> writes:

> From: Rafael J. Wysocki <rjw@xxxxxxx>
>
> Make generic PM domains support system-wide power transitions
> (system suspend and hibernation). Add suspend, resume, freeze, thaw,
> poweroff and restore callbacks to be associated with struct
> generic_pm_domain objects and make pm_genpd_init() use them as
> appropriate.
>
> The new callbacks do nothing for devices belonging to power domains
> that were powered down at run time (before the transition).

Thinking about this some more, how is a driver supposed to reconfigure
wakeups during suspend if it has already been runtime suspended?

For example, assume a device where device_may_wakeup() == false. This
means wakeups during *suspend* are disabled, but wakeups wakeups are
assumed to enabled when it is runtime suspended.

So now, assume this device is RPM_SUSPENDED, it has wakeups *enabled*,
and then system suspend comes along.

With this current patch, the driver will never receive any callbacks, so
it can never disable its wakeups.

Am I missing something?

Kevin
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