[PATCH] i2c: nomadik: Fixup system suspend
Ulf Hansson
ulf.hansson at linaro.org
Thu May 15 00:15:06 PDT 2014
On 6 May 2014 11:31, Ulf Hansson <ulf.hansson at linaro.org> wrote:
> On 10 April 2014 20:49, Linus Walleij <linus.walleij at linaro.org> wrote:
>> On Thu, Apr 10, 2014 at 3:59 PM, Ulf Hansson <ulf.hansson at linaro.org> wrote:
>>
>>> For !CONFIG_PM_RUNTIME, the device were never put back into active
>>> state while resuming.
>>>
>>> For CONFIG_PM_RUNTIME, we blindly trusted the device to be inactive
>>> while we were about to handle it at suspend late, which is just too
>>> optimistic.
>>>
>>> Even if the driver uses pm_runtime_put_sync() after each tranfer to
>>> return it's runtime PM resources, there are no guarantees this will
>>> actually mean the device will inactivated. The reason is that the PM
>>> core will prevent runtime suspend during system suspend, and thus when
>>> a transfer occurs during the early phases of system suspend the device
>>> will be kept active after the transfer.
>>>
>>> To handle both issues above, use pm_runtime_force_suspend|resume() from
>>> the system suspend|resume callbacks.
>>>
>>> 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>
>>
>> Acked-by: Linus Walleij <linus.walleij at linaro.org>
>
> Hi Wolfram,
>
> This patch as has been around for a while (in some other versions as
> well), would you mind picking it up for 3.16?
>
Ping.
I noticed you merged my other i2c-nomadik patch yesterday - thought I
might remind you about this one as well.
Kind regards
Ulf Hansson
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