Re: [PATCH v2 3/3] gpio: rcar: Use WAKEUP_PATH driver PM flag

From: Rafael J. Wysocki
Date: Tue Jan 02 2018 - 05:27:02 EST


On Tue, Jan 2, 2018 at 10:37 AM, Geert Uytterhoeven
<geert@xxxxxxxxxxxxxx> wrote:
> Hi Linus,
>
> On Tue, Jan 2, 2018 at 10:27 AM, Linus Walleij <linus.walleij@xxxxxxxxxx> wrote:
>> On Fri, Dec 29, 2017 at 2:31 PM, Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote:
>>> From: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
>>> Since commit ab82fa7da4dce5c7 ("gpio: rcar: Prevent module clock disable
>>> when wake-up is enabled"), when a GPIO is used for wakeup, the GPIO block's
>>> module clock (if exists) is manually kept running during system suspend, to
>>> make sure the device stays active.
>>>
>>> However, this explicit clock handling is merely a workaround for a failure
>>> to properly communicate wakeup information to the PM core. Instead, set the
>>> WAKEUP_PATH driver PM flag to indicate that the device is part of the
>>> wakeup path, which further also enables middle-layers and PM domains (like
>>> genpd) to act on this.
>>>
>>> In case the device is attached to genpd and depending on if it has an
>>> active wakeup configuration, genpd will keep the device active (the clock
>>> running) during system suspend when needed. This enables us to remove all
>>> explicit clock handling code from the driver, so let's do that as well.
>>>
>>> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
>>> [Ulf: Converted to use the WAKEUP_PATH driver PM flag]
>>> Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
>>
>> Acked-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
>>
>> I guess it is dependent on the other patches?
>
> Yes, it depends on (a) a clock patch queued in clk-next for v4.16, and (b) a PM
> patch introducing WAKEUP_PATH. Applying it prematurely will cause build
> or runtime issues.

Plus, I'm not going to apply the WAKEUP_PATH thing just yet.

At least not in its current version.

Thanks,
Rafael