Re: [PATCH] PCI: Set device power state to PCI_D0 for device withoutnative PM support

From: Yinghai Lu
Date: Thu Oct 06 2011 - 12:10:08 EST


On Wed, Oct 5, 2011 at 12:41 PM, Rafael J. Wysocki <rjw@xxxxxxx> wrote:
> Hi,
>>   drivers/pci/pci.c |    3 +++
>>   1 files changed, 3 insertions(+), 0 deletions(-)
>>
>> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
>> index e9651f0..ca8c82d 100644
>> --- a/drivers/pci/pci.c
>> +++ b/drivers/pci/pci.c
>> @@ -664,6 +664,9 @@ static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state)
>>                  error = platform_pci_set_power_state(dev, state);
>>                  if (!error)
>>                          pci_update_current_state(dev, state);
>> +               /* Fall back to PCI_D0 if native PM is not supported */
>> +               else if (!dev->pm_cap)
>> +                       dev->current_state = PCI_D0;
>>          } else {
>>                  error = -ENODEV;
>>                  /* Fall back to PCI_D0 if native PM is not supported */
>>
>
> I have some vague memories that we tried that and it broke something.

Do have any hint for us to dig out the configuration for failing?

>
> How thoroughly has it been tested?

tested in setups with intel cpus from Nehalem.

Yinghai
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/