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

From: Rafael J. Wysocki
Date: Thu Sep 29 2022 - 06:06:51 EST


On Wed, Sep 28, 2022 at 11:10 PM Raul Rangel <rrangel@xxxxxxxxxxxx> wrote:
>
> On Sat, Sep 24, 2022 at 11:00 AM Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote:
> >
> > On Wed, Sep 21, 2022 at 5:52 PM Raul E Rangel <rrangel@xxxxxxxxxxxx> 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@xxxxxxxxxxxx>
> > > ---
> > >
> > > 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.

That's fine.

> > > - } 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

Thanks!

> > > + } 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.