drm/tegra: Clarify how panel modes override others

When a panel advertises one or more modes, they are used exclusively.
Other methods for obtaining the mode, such as DDC as used for HDMI or
binary EDID blobs embedded in the DT, are ignored. The panel drivers
should be providing this functionality if they want to expose it as
well.

Signed-off-by: Thierry Reding <treding@nvidia.com>

diff --git a/drivers/gpu/drm/tegra/output.c b/drivers/gpu/drm/tegra/output.c
index f1b5030f55e33e8c78a3f0c2c1b24528a3fd12aa..921e4001a09021c8478ce9d634bd604a04271a82 100644 (file)
--- a/drivers/gpu/drm/tegra/output.c
+++ b/drivers/gpu/drm/tegra/output.c
@@ -18,6 +18,10 @@ static int tegra_connector_get_modes(struct drm_connector *connector)
        struct edid *edid = NULL;
        int err = 0;
 
+       /*
+        * If the panel provides one or more modes, use them exclusively and
+        * ignore any other means of obtaining a mode.
+        */
        if (output->panel) {
                err = output->panel->funcs->get_modes(output->panel);
                if (err > 0)