ACPI video: check cap._DDC flag before getting EDID

cap._DDC is defined but never used.
Check this flag now and don't try to get EDID for video output devices with this flag cleared.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 81766ebec843..177b4ddc3479 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -1275,6 +1275,9 @@ int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
                 if (!video_device)
                         continue;
 
+                if (!video_device->cap._DDC)
+                        continue;
+
                 if (type) {
                         switch (type) {
                         case ACPI_VIDEO_DISPLAY_CRT: