Re: [PATCH v5 08/13] ACPI: PM: Take wake IRQ into consideration when entering suspend-to-idle

From: Raul Rangel <rrangel@chromium.org>
To: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
	linux-input <linux-input@vger.kernel.org>,
	Tim Van Patten <timvp@google.com>,
	Mika Westerberg <mika.westerberg@linux.intel.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Dmitry Torokhov <dmitry.torokhov@gmail.com>,
	"jingle.wu" <jingle.wu@emc.com.tw>,
	Hans de Goede <hdegoede@redhat.com>,
	Mario Limonciello <mario.limonciello@amd.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	Len Brown <lenb@kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v5 08/13] ACPI: PM: Take wake IRQ into consideration when entering suspend-to-idle
Date: Wed, 28 Sep 2022 15:10:40 -0600	[thread overview]
Message-ID: <CAHQZ30BZ5jnTY4DQD5mxpnLcLxn5Oo=izB1+f06JOqXU5VGz_A@mail.gmail.com> (raw)
In-Reply-To: <CAJZ5v0g57mF-4ZC2ajL5+JE+q9y=fW1G-OXR8tuOk4TYxHPWtQ@mail.gmail.com>

On Sat, Sep 24, 2022 at 11:00 AM Rafael J. Wysocki <rafael@kernel.org> wrote:
>
> On Wed, Sep 21, 2022 at 5:52 PM Raul E Rangel <rrangel@chromium.org> wrote:
> >
> > This change adds support for ACPI devices that use ExclusiveAndWake or
> > SharedAndWake in their _CRS GpioInt definition (instead of using _PRW),
> > and also provide power resources. Previously the ACPI subsystem had no
> > idea if the device had a wake capable interrupt armed. This resulted
> > in the ACPI device PM system placing the device into D3Cold, and thus
> > cutting power to the device. With this change we will now query the
> > _S0W method to figure out the appropriate wake capable D-state.
> >
> > Signed-off-by: Raul E Rangel <rrangel@chromium.org>
> > ---
> >
> > Changes in v5:
> > - Go back to using adev->wakeup.flags.valid to keep the diff cleaner
> > - Fix a typo in comment
> >
> >  drivers/acpi/device_pm.c | 19 +++++++++++++++++--
> >  1 file changed, 17 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
> > index 9dce1245689ca2..3111fc426e04fd 100644
> > --- a/drivers/acpi/device_pm.c
> > +++ b/drivers/acpi/device_pm.c

> > @@ -681,8 +681,23 @@ static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev,
> >                 d_min = ret;
> >                 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
> >                         && adev->wakeup.sleep_state >= target_state;
Just an FYI, I didn't update the code that handles the target state >
S0. I need to get a
device that has S3 capabilities and the correct firmware to test this.
I figure I can do
that as a different patch when I have time to test with an S3 device.

> > -       } else {
> > -               wakeup = adev->wakeup.flags.valid;
> > +       } else if (adev->wakeup.flags.valid) {
> > +               /* ACPI GPE specified in _PRW. */
> > +               wakeup = true;

>
> I would retain the "else" clause as it was and just add a new "else
> if" one before it.
>
Done

> > +       } else if (device_may_wakeup(dev) && dev->power.wakeirq) {
> > +               /*
> > +                * The ACPI subsystem doesn't manage the wake bit for IRQs
> > +                * defined with ExclusiveAndWake and SharedAndWake. Instead we
> > +                * expect them to be managed via the PM subsystem. Drivers
> > +                * should call dev_pm_set_wake_irq to register an IRQ as a wake
> > +                * source.
> > +                *
> > +                * If a device has a wake IRQ attached we need to check the
> > +                * _S0W method to get the correct wake D-state. Otherwise we
> > +                * end up putting the device into D3Cold which will more than
> > +                * likely disable wake functionality.
> > +                */
> > +               wakeup = true;
> >         }
> >
> >         /*
> > --

I'll send out v6 soon unless anyone else has any comments.