drm/atomic: Change drm_atomic_helper_swap_state to return an error.

We want to change swap_state to wait indefinitely, but to do this
swap_state should wait interruptibly. This requires propagating
the error to each driver.

Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
Cc: intel-gfx@lists.freedesktop.org
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170711143314.2148-3-maarten.lankhorst@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[mlankhorst: Fix typos in swap_state documentation (seanpaul)]
Reviewed-by: Sean Paul <seanpaul@chromium.org>]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 2f67511..8d8221a 100644 (file)
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -1510,10 +1510,8 @@ int drm_atomic_helper_commit(struct drm_device *dev,
 
        if (!nonblock) {
                ret = drm_atomic_helper_wait_for_fences(dev, state, true);
-               if (ret) {
-                       drm_atomic_helper_cleanup_planes(dev, state);
-                       return ret;
-               }
+               if (ret)
+                       goto err;
        }
 
        /*
@@ -1522,7 +1520,9 @@ int drm_atomic_helper_commit(struct drm_device *dev,
         * the software side now.
         */
 
-       drm_atomic_helper_swap_state(state, true);
+       ret = drm_atomic_helper_swap_state(state, true);
+       if (ret)
+               goto err;
 
        /*
         * Everything below can be run asynchronously without the need to grab
@@ -1551,6 +1551,10 @@ int drm_atomic_helper_commit(struct drm_device *dev,
                commit_tail(state);
 
        return 0;
+
+err:
+       drm_atomic_helper_cleanup_planes(dev, state);
+       return ret;
 }
 EXPORT_SYMBOL(drm_atomic_helper_commit);
 
@@ -2228,14 +2232,14 @@ EXPORT_SYMBOL(drm_atomic_helper_cleanup_planes);
 /**
  * drm_atomic_helper_swap_state - store atomic state into current sw state
  * @state: atomic state
- * @stall: stall for proceeding commits
+ * @stall: stall for preceeding commits
  *
  * This function stores the atomic state into the current state pointers in all
  * driver objects. It should be called after all failing steps have been done
  * and succeeded, but before the actual hardware state is committed.
  *
  * For cleanup and error recovery the current state for all changed objects will
- * be swaped into @state.
+ * be swapped into @state.
  *
  * With that sequence it fits perfectly into the plane prepare/cleanup sequence:
  *
@@ -2254,8 +2258,12 @@ EXPORT_SYMBOL(drm_atomic_helper_cleanup_planes);
  * the &drm_plane.state, &drm_crtc.state or &drm_connector.state pointer. With
  * the current atomic helpers this is almost always the case, since the helpers
  * don't pass the right state structures to the callbacks.
+ *
+ * Returns:
+ *
+ * Always returns 0, cannot fail yet.
  */
-void drm_atomic_helper_swap_state(struct drm_atomic_state *state,
+int drm_atomic_helper_swap_state(struct drm_atomic_state *state,
                                  bool stall)
 {
        int i;
@@ -2339,6 +2347,8 @@ void drm_atomic_helper_swap_state(struct drm_atomic_state *state,
                state->private_objs[i].state = old_obj_state;
                obj->state = new_obj_state;
        }
+
+       return 0;
 }
 EXPORT_SYMBOL(drm_atomic_helper_swap_state);
 

diff --git a/include/drm/drm_atomic_helper.h b/include/drm/drm_atomic_helper.h
index 7db3438..5474806 100644 (file)
--- a/include/drm/drm_atomic_helper.h
+++ b/include/drm/drm_atomic_helper.h
@@ -86,8 +86,7 @@ void
 drm_atomic_helper_disable_planes_on_crtc(struct drm_crtc_state *old_crtc_state,
                                         bool atomic);
 
-void drm_atomic_helper_swap_state(struct drm_atomic_state *state,
-                                 bool stall);
+int drm_atomic_helper_swap_state(struct drm_atomic_state *state, bool stall);
 
 /* nonblocking commit helpers */
 int drm_atomic_helper_setup_commit(struct drm_atomic_state *state,