Re: [PATCH 1/1] ACPI: Support D3 COLD device for old BIOS

["Rafael J. Wysocki" <rjw@rjwysocki.net>]

On Tuesday, December 08, 2015 09:37:56 AM Ken Xue wrote:
> On Mon, 2015-12-07 at 23:48 +0100, Rafael J. Wysocki wrote:
> > On Monday, December 07, 2015 12:44:33 PM Ken Xue wrote:
> > > D3cold is only regarded as valid if the "_PR3" object is present
> > > for the given device after the commit <20dacb71ad28>
> > > (ACPI/PM: Reworkdevice power management to follow ACPI 6).
> > > 
> > > But some old BIOS only defined "_PS3" for the D3COLD device.
> > > And old kernel also believes the device has "_PS3" is a
> > > D3COLD device.
> > > 
> > > So, add some logics for supporting D3 COLD device for old BIOS
> > > which is compatible with earlier ACPI spec.
> > > 
> > > Signed-off-by: Ken Xue <Ken.Xue@amd.com>
> > > Reported-and-tested-by: Gang Long <Gang.Long@amd.com>
> > 
> > Well, what really is the problem?
> 
> My problem is that
> "acpi_device_can_poweroff" is called by "zpodd_init" in libata-zpodd.c. 
> And ZPODD feature only can be enabled when D3_COLD is valid.

This means that acpi_device_can_poweroff() needs to be updated.  What about
like this:

static inline bool acpi_device_can_poweroff(struct acpi_device *adev)
{
	return adev->power.states[ACPI_STATE_D3_COLD].flags.valid
		|| adev->power.states[ACPI_STATE_D3_HOT].flags.explicit_set;
}

Thanks,
Rafael