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@xxxxxxx> > Reported-and-tested-by: Gang Long <Gang.Long@xxxxxxx> Well, what really is the problem? acpi_device_set_power() has a special case specifically for D3cold and falls back to D3hot if D3cold has been requested but is not "valid". > --- > drivers/acpi/scan.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > index 01136b8..85c16bb 100644 > --- a/drivers/acpi/scan.c > +++ b/drivers/acpi/scan.c > @@ -979,7 +979,9 @@ static void acpi_bus_get_power_flags(struct acpi_device *device) > acpi_bus_init_power_state(device, i); > > INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources); > - if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources)) > + if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources) || > + ((acpi_gbl_FADT.header.revision < 6) && > + device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)) > device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1; > > /* Set defaults for D0 and D3hot states (always valid) */ > -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
