drm/i915: handle bogus VBT panel timing

We've seen cases in the wild where the VBT sync data is wrong, so add
some code to fix it up in that case, taking care to make sure that the
total is greater than the sync end.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Dave Airlie <airlied@linux.ie>

diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index 65be30dccc7767d8781cad444a317c43930a6064..fc28e2bbd5427e6030869724dfb9bd20b5797451 100644 (file)
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -111,6 +111,12 @@ parse_panel_data(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
        panel_fixed_mode->clock = dvo_timing->clock * 10;
        panel_fixed_mode->type = DRM_MODE_TYPE_PREFERRED;
 
+       /* Some VBTs have bogus h/vtotal values */
+       if (panel_fixed_mode->hsync_end > panel_fixed_mode->htotal)
+               panel_fixed_mode->htotal = panel_fixed_mode->hsync_end + 1;
+       if (panel_fixed_mode->vsync_end > panel_fixed_mode->vtotal)
+               panel_fixed_mode->vtotal = panel_fixed_mode->vsync_end + 1;
+
        drm_mode_set_name(panel_fixed_mode);
 
        dev_priv->vbt_mode = panel_fixed_mode;