drm/bridge: Make (pre/post) enable/disable callbacks optional

Instead of forcing bridges to implement empty callbacks make them all
optional.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
index bd93453..b365440 100644 (file)
--- a/drivers/gpu/drm/drm_bridge.c
+++ b/drivers/gpu/drm/drm_bridge.c
@@ -186,7 +186,8 @@ void drm_bridge_disable(struct drm_bridge *bridge)
 
        drm_bridge_disable(bridge->next);
 
-       bridge->funcs->disable(bridge);
+       if (bridge->funcs->disable)
+               bridge->funcs->disable(bridge);
 }
 EXPORT_SYMBOL(drm_bridge_disable);
 
@@ -206,7 +207,8 @@ void drm_bridge_post_disable(struct drm_bridge *bridge)
        if (!bridge)
                return;
 
-       bridge->funcs->post_disable(bridge);
+       if (bridge->funcs->post_disable)
+               bridge->funcs->post_disable(bridge);
 
        drm_bridge_post_disable(bridge->next);
 }
@@ -256,7 +258,8 @@ void drm_bridge_pre_enable(struct drm_bridge *bridge)
 
        drm_bridge_pre_enable(bridge->next);
 
-       bridge->funcs->pre_enable(bridge);
+       if (bridge->funcs->pre_enable)
+               bridge->funcs->pre_enable(bridge);
 }
 EXPORT_SYMBOL(drm_bridge_pre_enable);
 
@@ -276,7 +279,8 @@ void drm_bridge_enable(struct drm_bridge *bridge)
        if (!bridge)
                return;
 
-       bridge->funcs->enable(bridge);
+       if (bridge->funcs->enable)
+               bridge->funcs->enable(bridge);
 
        drm_bridge_enable(bridge->next);
 }

diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index d70c869..4359a84 100644 (file)
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -917,6 +917,8 @@ struct drm_bridge_funcs {
         *
         * The bridge can assume that the display pipe (i.e. clocks and timing
         * signals) feeding it is still running when this callback is called.
+        *
+        * The disable callback is optional.
         */
        void (*disable)(struct drm_bridge *bridge);
 
@@ -933,6 +935,8 @@ struct drm_bridge_funcs {
         * The bridge must assume that the display pipe (i.e. clocks and timing
         * singals) feeding it is no longer running when this callback is
         * called.
+        *
+        * The post_disable callback is optional.
         */
        void (*post_disable)(struct drm_bridge *bridge);
 
@@ -961,6 +965,8 @@ struct drm_bridge_funcs {
         * will not yet be running when this callback is called. The bridge must
         * not enable the display link feeding the next bridge in the chain (if
         * there is one) when this callback is called.
+        *
+        * The pre_enable callback is optional.
         */
        void (*pre_enable)(struct drm_bridge *bridge);
 
@@ -978,6 +984,8 @@ struct drm_bridge_funcs {
         * signals) feeding it is running when this callback is called. This
         * callback must enable the display link feeding the next bridge in the
         * chain if there is one.
+        *
+        * The enable callback is optional.
         */
        void (*enable)(struct drm_bridge *bridge);
 };