Re: [PATCH] ACPI: evaluate _PS3 when entering D3 Cold

huang ying
2012-04-26T08:55:16Z

On Wed, Apr 25, 2012 at 5:15 AM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> On Tuesday, April 24, 2012, Aaron Lu wrote:
>> On Tue, Apr 24, 2012 at 09:15:37PM +0800, Lin Ming wrote:
>> > >> > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
>> > >> > index 7417267..734d946 100644
>> > >> > --- a/drivers/acpi/scan.c
>> > >> > +++ b/drivers/acpi/scan.c
>> > >> > @@ -908,6 +908,10 @@ static int acpi_bus_get_power_flags(struct acpi_device *device)
>> > >> >     device->power.states[ACPI_STATE_D3].flags.valid = 1;
>> > >> >     device->power.states[ACPI_STATE_D3].power = 0;
>> > >> >
>> > >> > +   /* Also set D3cold's explicit flag when _PS3 exists */
>> > >> > +   if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
>> > >> > +           device->power.states[ACPI_STATE_D3].flags.explicit_set = 1;
>> > >>
>> > >> We should use ACPI_STATE_D3_COLD instead of ACPI_STATE_D3 to make thing
>> > >> clear.
>> > >>
>> > > Thanks for your suggestion.
>> > >
>> > > Well, considering all those ACPI_STATE_D3 used in tree, I don't think I
>> > > should use ACPI_STATE_D3_COLD here, especially the two lines above are
>> > > still using ACPI_STATE_D3.
>> > >
>> > > But if that is desired, we should probably change all the existing
>> > > ACPI_STATE_D3 macros to ACPI_STATE_D3_COLD to make things clear.
>> > >
>> > > Or we all use ACPI_STATE_D3, since it is defined as 4 and means D3 cold,
>> > > and people will learn this, won't they?
>> > >
>> > > What do you think?
>> >
>> > OK.
>> >
>> > But we may do more cleanup later.
>> >
>>
>> Sure :-)
>> I think the first thing to do is to agree on which macro should be used,
>> ACPI_STATE_D3 or ACPI_STATE_D3_COLD. And then replace the other one
>> altogether.
>
> I'd prefer to use ACPI_STATE_D3 wherever it makes sense, because that's
> also well defined in older versions of ACPI (think pre-ACPI-4.0 BIOSes).

Because the relationship between ACPI_STATE_D3 and ACPI_STATE_D3_COLD
is confusing, I suggest to add some comments whenever will refer to D3
or D3_COLD.

Best Regards,
Huang Ying