drm/i915: Set preferred mode for integrated TV according to TV format

In order to get best possible quality image we chose 640x480 for
NTSC, PAL and 480p, 1280x720 for 720p, 1920x1080 for 1080i/p
TV format respectively.

Signed-off-by: Ma Ling <ling.ma@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

diff --git a/drivers/gpu/drm/i915/intel_tv.c b/drivers/gpu/drm/i915/intel_tv.c
index a43c98e3f0777dc6de4416a8f00f5c9c8dedcd82..da4ab4dc16306b6fc4b7727da0954f7736a290cb 100644 (file)
--- a/drivers/gpu/drm/i915/intel_tv.c
+++ b/drivers/gpu/drm/i915/intel_tv.c
@@ -1490,6 +1490,27 @@ static struct input_res {
        {"1920x1080", 1920, 1080},
 };
 
+/*
+ * Chose preferred mode  according to line number of TV format
+ */
+static void
+intel_tv_chose_preferred_modes(struct drm_connector *connector,
+                              struct drm_display_mode *mode_ptr)
+{
+       struct intel_output *intel_output = to_intel_output(connector);
+       const struct tv_mode *tv_mode = intel_tv_mode_find(intel_output);
+
+       if (tv_mode->nbr_end < 480 && mode_ptr->vdisplay == 480)
+               mode_ptr->type |= DRM_MODE_TYPE_PREFERRED;
+       else if (tv_mode->nbr_end > 480) {
+               if (tv_mode->progressive == true && tv_mode->nbr_end < 720) {
+                       if (mode_ptr->vdisplay == 720)
+                               mode_ptr->type |= DRM_MODE_TYPE_PREFERRED;
+               } else if (mode_ptr->vdisplay == 1080)
+                               mode_ptr->type |= DRM_MODE_TYPE_PREFERRED;
+       }
+}
+
 /**
  * Stub get_modes function.
  *
@@ -1544,6 +1565,7 @@ intel_tv_get_modes(struct drm_connector *connector)
                mode_ptr->clock = (int) tmp;
 
                mode_ptr->type = DRM_MODE_TYPE_DRIVER;
+               intel_tv_chose_preferred_modes(connector, mode_ptr);
                drm_mode_probed_add(connector, mode_ptr);
                count++;
        }