drm: work around EDIDs with bad htotal/vtotal values

We did this on the userspace side, but we need a similar fix for the
kernel.

Fixes LP #460664.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index cea665d86dd3..b54ba63d506e 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -662,6 +662,12 @@ static struct drm_display_mode *drm_mode_detailed(struct drm_device *dev,
                 return NULL;
         }
 
+        /* Some EDIDs have bogus h/vtotal values */
+        if (mode->hsync_end > mode->htotal)
+                mode->htotal = mode->hsync_end + 1;
+        if (mode->vsync_end > mode->vtotal)
+                mode->vtotal = mode->vsync_end + 1;
+
         drm_mode_set_name(mode);
 
         if (pt->misc & DRM_EDID_PT_INTERLACED)