2 files changed, 30 insertions, 7 deletions

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index d0c3611402da..379b6c833bb2 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -599,7 +599,7 @@ disable_outputs(struct drm_device *dev, struct drm_atomic_state *old_state)
                         encoder->bridge->funcs->disable(encoder->bridge);
 
                 /* Right function depends upon target state. */
-                if (connector->state->crtc)
+                if (connector->state->crtc && funcs->prepare)
                         funcs->prepare(encoder);
                 else if (funcs->disable)
                         funcs->disable(encoder);
@@ -628,7 +628,7 @@ disable_outputs(struct drm_device *dev, struct drm_atomic_state *old_state)
                 funcs = crtc->helper_private;
 
                 /* Right function depends upon target state. */
-                if (crtc->state->enable)
+                if (crtc->state->enable && funcs->prepare)
                         funcs->prepare(crtc);
                 else if (funcs->disable)
                         funcs->disable(crtc);
@@ -792,8 +792,12 @@ void drm_atomic_helper_commit_post_planes(struct drm_device *dev,
 
                 funcs = crtc->helper_private;
 
-                if (crtc->state->enable)
-                        funcs->commit(crtc);
+                if (crtc->state->enable) {
+                        if (funcs->enable)
+                                funcs->enable(crtc);
+                        else
+                                funcs->commit(crtc);
+                }
         }
 
         for (i = 0; i < old_state->num_connector; i++) {
@@ -819,7 +823,10 @@ void drm_atomic_helper_commit_post_planes(struct drm_device *dev,
                 if (encoder->bridge)
                         encoder->bridge->funcs->pre_enable(encoder->bridge);
 
-                funcs->commit(encoder);
+                if (funcs->enable)
+                        funcs->enable(encoder);
+                else
+                        funcs->commit(encoder);
 
                 if (encoder->bridge)
                         encoder->bridge->funcs->enable(encoder->bridge);
diff --git a/include/drm/drm_crtc_helper.h b/include/drm/drm_crtc_helper.h
index e76828d81a8b..4b19f7a20d62 100644
--- a/include/drm/drm_crtc_helper.h
+++ b/include/drm/drm_crtc_helper.h
@@ -58,11 +58,19 @@ enum mode_set_atomic {
  * @mode_set_base_atomic: non-blocking mode set (used for kgdb support)
  * @load_lut: load color palette
  * @disable: disable CRTC when no longer in use
+ * @enable: enable CRTC
  * @atomic_check: check for validity of an atomic state
  * @atomic_begin: begin atomic update
  * @atomic_flush: flush atomic update
  *
  * The helper operations are called by the mid-layer CRTC helper.
+ *
+ * Note that with atomic helpers @dpms, @prepare and @commit hooks are
+ * deprecated. Used @enable and @disable instead exclusively.
+ *
+ * With legacy crtc helpers there's a big semantic difference between @disable
+ * and the other hooks: @disable also needs to release any resources acquired in
+ * @mode_set (like shared PLLs).
  */
 struct drm_crtc_helper_funcs {
         /*
@@ -93,8 +101,8 @@ struct drm_crtc_helper_funcs {
         /* reload the current crtc LUT */
         void (*load_lut)(struct drm_crtc *crtc);
 
-        /* disable crtc when not in use - more explicit than dpms off */
         void (*disable)(struct drm_crtc *crtc);
+        void (*enable)(struct drm_crtc *crtc);
 
         /* atomic helpers */
         int (*atomic_check)(struct drm_crtc *crtc,
@@ -115,8 +123,16 @@ struct drm_crtc_helper_funcs {
  * @get_crtc: return CRTC that the encoder is currently attached to
  * @detect: connection status detection
  * @disable: disable encoder when not in use (overrides DPMS off)
+ * @enable: enable encoder
  *
  * The helper operations are called by the mid-layer CRTC helper.
+ *
+ * Note that with atomic helpers @dpms, @prepare and @commit hooks are
+ * deprecated. Used @enable and @disable instead exclusively.
+ *
+ * With legacy crtc helpers there's a big semantic difference between @disable
+ * and the other hooks: @disable also needs to release any resources acquired in
+ * @mode_set (like shared PLLs).
  */
 struct drm_encoder_helper_funcs {
         void (*dpms)(struct drm_encoder *encoder, int mode);
@@ -135,8 +151,8 @@ struct drm_encoder_helper_funcs {
         /* detect for DAC style encoders */
         enum drm_connector_status (*detect)(struct drm_encoder *encoder,
                                             struct drm_connector *connector);
-        /* disable encoder when not in use - more explicit than dpms off */
         void (*disable)(struct drm_encoder *encoder);
+        void (*enable)(struct drm_encoder *encoder);
 };
 
 /**