On Thu, Jun 13, 2019 at 12:14:02AM +0200, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> Commit d491f2b75237 ("PCI: PM: Avoid possible suspend-to-idle issue")
> attempted to avoid a problem with devices whose drivers want them to
> stay in D0 over suspend-to-idle and resume, but it did not go as far
> as it should with that.
>
> Namely, first of all, it is questionable to change the power state
> of a PCI bridge with a device in D0 under it, but that is not
> actively prevented from happening during system-wide PM transitions,
> so use the skip_bus_pm flag introduced by commit d491f2b75237 for
> that.
>
> Second, the configuration of devices left in D0 (whatever the reason)
> during suspend-to-idle need not be changed and attempting to put them
> into D0 again by force may confuse some firmware, so explicitly avoid
> doing that.
>
> Fixes: d491f2b75237 ("PCI: PM: Avoid possible suspend-to-idle issue")
> Reported-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Reviewed-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
