[PATCH 14/17] i2c: nomadik: Fixup deployment of runtime PM

Ulf Hansson ulf.hansson at linaro.org
Mon Feb 10 05:14:46 EST 2014

On 5 February 2014 15:34, Linus Walleij <linus.walleij at linaro.org> wrote:
> On Tue, Feb 4, 2014 at 4:58 PM, Ulf Hansson <ulf.hansson at linaro.org> wrote:
>> Since the device is active while a successful probe has been completed,
>> the reference counting for the clock will be screwed up and never reach
>> zero.
>> The issue is resolved by implementing runtime PM callbacks and let them
>> handle the resources accordingly, including the clock.
>> Cc: Alessandro Rubini <rubini at unipv.it>
>> Cc: Linus Walleij <linus.walleij at linaro.org>
>> Cc: Wolfram Sang <wsa at the-dreams.de>
>> Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
> Hm do I read it right as patch 13 breaks runtime PM by leaving
> the device active after probe() and this patch
> 14 fixes it again? Maybe these two patches should be squashed
> then.

You are right; but the driver will still be working, you just don't
get the benefit from inactivating the device at request inactivity -
as you pointed out.

The reason for why I wanted to do this as separate steps was to make
it easier for reviewing, otherwise the patch(es) would have been quite
big and messy. I am for sure open to  adopt to your proposal, but just
wanted to give you some more background, before I go ahead and send a

Kind regards
Ulf Hansson

> Yours,
> Linus Walleij

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