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

Aaron Lu
2012-04-24T02:07:21Z

On Mon, Apr 23, 2012 at 09:50:57PM +0200, Rafael J. Wysocki wrote:
> > diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
> > index 3263b68..187433f 100644
> > --- a/drivers/acpi/bus.c
> > +++ b/drivers/acpi/bus.c
> > @@ -273,6 +273,9 @@ static int __acpi_bus_set_power(struct acpi_device *device, int state)
> > }
> > } else {
> > if (device->power.states[state].flags.explicit_set) {
> > + /* evaluate _PS3 instead of _PS4 when entering D3Cold */
> > + if (state == ACPI_STATE_D3)
> > + object_name[3] -= 1;
>
> Can you just put '3' here directly? That'll be much cleaner than the
> subtraction (that could have been -- as well).
>
> > status = acpi_evaluate_object(device->handle,
> > object_name, NULL, NULL);
> > if (ACPI_FAILURE(status)) {
> > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
> > index 7417267..de2ae10 100644
> > --- a/drivers/acpi/scan.c
> > +++ b/drivers/acpi/scan.c
> > @@ -887,8 +887,12 @@ static int acpi_bus_get_power_flags(struct acpi_device *device)
> > /* Evaluate "_PSx" to see if we can do explicit sets */
> > object_name[2] = 'S';
> > status = acpi_get_handle(device->handle, object_name, &handle);
> > - if (ACPI_SUCCESS(status))
> > + if (ACPI_SUCCESS(status)) {
> > ps->flags.explicit_set = 1;
> > + /* Also set D3Cold's explicit flag when _PS3 exists */
> > + if (i == ACPI_STATE_D3_HOT)
> > + (ps+1)->flags.explicit_set = 1;
>
> Please don't use pointer arithmetics here. I know it _happens_ to work,
> but I don't think it's appropriate in this situation at all.
>

Thanks for the suggestions.

What about this?

diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 3263b68..3a7860f 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -273,6 +273,9 @@ static int __acpi_bus_set_power(struct acpi_device *device, int state)
}
} else {
if (device->power.states[state].flags.explicit_set) {
+ /* Evaluate _PS3 when entering D3cold */
+ if (state == ACPI_STATE_D3)
+ object_name[3] = '3';
status = acpi_evaluate_object(device->handle,
object_name, NULL, NULL);
if (ACPI_FAILURE(status)) {
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;
+
acpi_bus_init_power(device);

return 0;

Thanks,
Aaron