drm: disable encoders before re-routing them

In some cases we may receive a mode config that has a different
CRTC<->encoder map that the current configuration.  In that case, we
need to disable any re-routed encoders before setting the mode,
otherwise they may not pick up the new CRTC (if the output types are
incompatible for example).

Tested-by: Kristian Høgsberg <krh@bitplanet.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Dave Airlie <airlied@linux.ie>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/drm/drm_crtc_helper.h b/include/drm/drm_crtc_helper.h
index 0b0d236c2154..c7d4b2e606a5 100644
--- a/include/drm/drm_crtc_helper.h
+++ b/include/drm/drm_crtc_helper.h
@@ -76,6 +76,7 @@ struct drm_encoder_helper_funcs {
         void (*mode_set)(struct drm_encoder *encoder,
                          struct drm_display_mode *mode,
                          struct drm_display_mode *adjusted_mode);
+        struct drm_crtc *(*get_crtc)(struct drm_encoder *encoder);
         /* detect for DAC style encoders */
         enum drm_connector_status (*detect)(struct drm_encoder *encoder,
                                             struct drm_connector *connector);