Re: [PATCH] ACPI:video: skip evaluating _DOD when it does not exist

["Rafael J. Wysocki" <rjw@rjwysocki.net>]

On Monday, June 06, 2016 09:52:29 AM Aaron Lu wrote:
> On 06/06/2016 09:36 AM, Alex Hung wrote:
> > On Fri, Jun 3, 2016 at 2:04 PM, Aaron Lu <aaron.lu@intel.com> wrote:
> >> On Fri, May 27, 2016 at 03:47:06PM +0800, Alex Hung wrote:
> >>> Some system supports hybrid graphics and its discrete VGA
> >>> does not have any connectors and therefore has no _DOD method.
> >>>
> >>> Signed-off-by: Alex Hung <alex.hung@canonical.com>
> >>> ---
> >>>  drivers/acpi/acpi_video.c |    3 +++
> >>>  1 file changed, 3 insertions(+)
> >>>
> >>> diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
> >>> index 5fdac39..549cdbe 100644
> >>> --- a/drivers/acpi/acpi_video.c
> >>> +++ b/drivers/acpi/acpi_video.c
> >>> @@ -1211,6 +1211,9 @@ static int acpi_video_device_enumerate(struct acpi_video_bus *video)
> >>>       union acpi_object *dod = NULL;
> >>>       union acpi_object *obj;
> >>>
> >>> +     if (!video->cap._DOD)
> >>> +             return AE_NOT_EXIST;
> >>> +
> >>>       status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
> >>>       if (!ACPI_SUCCESS(status)) {
> >>>               ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
> >>
> >> Is the patch supposed to avoid the above error message?
> >> I'm OK with the patch though, it's just not clear to me the point since
> >> the acpi_evaluate_object should probably also return AE_NOT_EXIST.
> > 
> > Yes it is to avoid the error message.  As _DOD is checked and it is
> > known a specific video device does not have it, the error message can
> > be confusing.
> 
> I see, thanks.
> 
> Reviewed-by: Aaron Lu <aaron.lu@intel.com>

Patch applied, thanks!