drm: ignore EDID with really tiny modes.

Some EDIDs lie and report tiny modes that aren't possible. Ignore
these modes.

Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index ca9c616..6f6b264 100644 (file)
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -289,6 +289,11 @@ static struct drm_display_mode *drm_mode_detailed(struct drm_device *dev,
        struct drm_display_mode *mode;
        struct detailed_pixel_timing *pt = &timing->data.pixel_data;
 
+       /* ignore tiny modes */
+       if (((pt->hactive_hi << 8) | pt->hactive_lo) < 64 ||
+           ((pt->vactive_hi << 8) | pt->hactive_lo) < 64)
+               return NULL;
+
        if (pt->stereo) {
                printk(KERN_WARNING "stereo mode not supported\n");
                return NULL;