1 files changed, 25 insertions, 9 deletions

diff --git a/drivers/gpu/drm/omapdrm/omap_connector.c b/drivers/gpu/drm/omapdrm/omap_connector.c
index 302f2ed245d0..b8317b697083 100644
--- a/drivers/gpu/drm/omapdrm/omap_connector.c
+++ b/drivers/gpu/drm/omapdrm/omap_connector.c
@@ -218,20 +218,41 @@ static int omap_connector_get_modes(struct drm_connector *connector)
 
         /*
          * If display exposes EDID, then we parse that in the normal way to
-         * build table of supported modes. Otherwise (ie. fixed resolution
-         * LCD panels) we just return a single mode corresponding to the
-         * currently configured timings.
+         * build table of supported modes.
          */
         dssdev = omap_connector_find_device(connector,
                                             OMAP_DSS_DEVICE_OP_EDID);
         if (dssdev)
                 return omap_connector_get_modes_edid(connector, dssdev);
 
+        /*
+         * Otherwise we have either a fixed resolution panel or an output that
+         * doesn't support modes discovery (e.g. DVI or VGA with the DDC bus
+         * unconnected, or analog TV). Start by querying the size.
+         */
+        dssdev = omap_connector->display;
+        if (dssdev->driver && dssdev->driver->get_size)
+                dssdev->driver->get_size(dssdev,
+                                         &connector->display_info.width_mm,
+                                         &connector->display_info.height_mm);
+
+        /*
+         * Iterate over the pipeline to find the first device that can provide
+         * timing information. If we can't find any, we just let the KMS core
+         * add the default modes.
+         */
+        for (dssdev = omap_connector->display; dssdev; dssdev = dssdev->src) {
+                if (dssdev->ops->get_timings)
+                        break;
+        }
+        if (!dssdev)
+                return 0;
+
+        /* Add a single mode corresponding to the fixed panel timings. */
         mode = drm_mode_create(connector->dev);
         if (!mode)
                 return 0;
 
-        dssdev = omap_connector->display;
         dssdev->ops->get_timings(dssdev, &vm);
 
         drm_display_mode_from_videomode(&vm, mode);
@@ -240,11 +261,6 @@ static int omap_connector_get_modes(struct drm_connector *connector)
         drm_mode_set_name(mode);
         drm_mode_probed_add(connector, mode);
 
-        if (dssdev->driver && dssdev->driver->get_size)
-                dssdev->driver->get_size(dssdev,
-                                         &connector->display_info.width_mm,
-                                         &connector->display_info.height_mm);
-
         return 1;
 }