drm/connector: Allow max possible encoders to attach to a connector

[sfrench/cifs-2.6.git] / drivers / gpu / drm / drm_crtc_helper.c

diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c
index 6dd49a60deacdd88a0205b4e23d563e7ec90754f..c3c8d4b70dbd313d6a8433758ad4d89168a2820d 100644 (file)
--- a/drivers/gpu/drm/drm_crtc_helper.c
+++ b/drivers/gpu/drm/drm_crtc_helper.c
@@ -36,6 +36,7 @@
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_atomic_uapi.h>
+#include <drm/drm_bridge.h>
 #include <drm/drm_crtc.h>
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_drv.h>
@@ -480,6 +481,22 @@ drm_crtc_helper_disable(struct drm_crtc *crtc)
        __drm_helper_disable_unused_functions(dev);
 }
 
+/*
+ * For connectors that support multiple encoders, either the
+ * .atomic_best_encoder() or .best_encoder() operation must be implemented.
+ */
+struct drm_encoder *
+drm_connector_get_single_encoder(struct drm_connector *connector)
+{
+       struct drm_encoder *encoder;
+
+       WARN_ON(hweight32(connector->possible_encoders) > 1);
+       drm_connector_for_each_possible_encoder(connector, encoder)
+               return encoder;
+
+       return NULL;
+}
+
 /**
  * drm_crtc_helper_set_config - set a new config from userspace
  * @set: mode set configuration
@@ -645,7 +662,11 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set,
                new_encoder = connector->encoder;
                for (ro = 0; ro < set->num_connectors; ro++) {
                        if (set->connectors[ro] == connector) {
-                               new_encoder = connector_funcs->best_encoder(connector);
+                               if (connector_funcs->best_encoder)
+                                       new_encoder = connector_funcs->best_encoder(connector);
+                               else
+                                       new_encoder = drm_connector_get_single_encoder(connector);
+
                                /* if we can't get an encoder for a connector
                                   we are setting now - then fail */
                                if (new_encoder == NULL)