Re: [PATCH] clockevents: don't suspend/resume if unused

From: Russell King - ARM Linux
Date: Fri Jan 16 2015 - 06:17:31 EST


On Fri, Jan 16, 2015 at 10:20:14AM +0100, Sylvain Rochet wrote:
> Hello Alexandre,
>
>
> On Fri, Jan 16, 2015 at 10:05:51AM +0100, Alexandre Belloni wrote:
> > There is no point in calling suspend/resume for unused
> > clockevents as they are already stopped and disabled.
> >
> > Furthermore, it can take some time to wait for some IPs to stop counting.
> >
> > Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
> > Reported-by: Sylvain Rochet <sylvain.rochet@xxxxxxxxxxxx>
>
> Indeed, this is way better from what I did.
>
>
> > + if (dev->suspend && dev->mode != CLOCK_EVT_MODE_UNUSED)
>
> I wonder if we should use > CLOCK_EVT_MODE_SHUTDOWN
> (or CLOCK_EVT_MODE_UNUSED || CLOCK_EVT_MODE_SHUTDOWN) instead of
> !CLOCK_EVT_MODE_UNUSED.

Definitely - consider the effect of the original patch set on a clock
source which is being used, has PM support, but does not have an
->enable callback.

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