drm/panel: simple: Set appropriate mode type

All modes exposed by simple panels should be tagged as driver defined
modes. Moreover, if a panel supports only one mode, this mode is
obviously the preferred one.

Doing this also fix a problem occurring when a 'video=' parameter is
passed on the kernel command line. In some cases the user provided mode
will be preferred over the simple panel ones, which might result in
unpredictable behavior.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Tested-by: Nicolas Ferre <nicolas.ferre@atmel.com>
[treding@nvidia.com: reshuffle some code for consistency]
Signed-off-by: Thierry Reding <treding@nvidia.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
index 847abee5ea36..a6d8a5dda424 100644
--- a/drivers/gpu/drm/panel/panel-simple.c
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -117,6 +117,12 @@ static int panel_simple_get_fixed_modes(struct panel_simple *panel)
                 }
 
                 drm_display_mode_from_videomode(&vm, mode);
+
+                mode->type |= DRM_MODE_TYPE_DRIVER;
+
+                if (panel->desc->num_modes == 1)
+                        mode->type |= DRM_MODE_TYPE_PREFERRED;
+
                 drm_mode_set_name(mode);
 
                 drm_mode_probed_add(connector, mode);
@@ -133,6 +139,11 @@ static int panel_simple_get_fixed_modes(struct panel_simple *panel)
                         continue;
                 }
 
+                mode->type |= DRM_MODE_TYPE_DRIVER;
+
+                if (panel->desc->num_modes == 1)
+                        mode->type |= DRM_MODE_TYPE_PREFERRED;
+
                 drm_mode_set_name(mode);
 
                 drm_mode_probed_add(connector, mode);