[PATCH 1/7] drm: Add drm_atomic_helper_wait_for_flip_done()

[Boris Brezillon]

Add an helper to wait for all page flips of an atomic state to be done.

Signed-off-by: Boris Brezillon <boris.brezillon at free-electrons.com>
---
 drivers/gpu/drm/drm_atomic_helper.c | 30 ++++++++++++++++++++++++++++++
 include/drm/drm_atomic_helper.h     |  3 +++
 2 files changed, 33 insertions(+)

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index fa2d8d7a602a..11f2d644771b 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -1166,6 +1166,36 @@ drm_atomic_helper_wait_for_vblanks(struct drm_device *dev,
 EXPORT_SYMBOL(drm_atomic_helper_wait_for_vblanks);
 
 /**
+ * drm_atomic_helper_wait_for_flip_done - wait for all page flips to be done
+ * @state: atomic state object
+ *
+ * Helper to, after atomic commit, wait for page flips on all effected
+ * crtcs (ie. before cleaning up old framebuffers using
+ * drm_atomic_helper_cleanup_planes()).
+ */
+void drm_atomic_helper_wait_for_flip_done(struct drm_device *dev,
+					  struct drm_atomic_state *state)
+{
+	struct drm_crtc_state *crtc_state;
+	struct drm_crtc *crtc;
+	int i;
+
+	for_each_crtc_in_state(state, crtc, crtc_state, i) {
+		struct drm_crtc_commit *commit = state->crtcs[i].commit;
+		int ret;
+
+		if (!commit)
+			continue;
+
+		ret = wait_for_completion_timeout(&commit->flip_done, 10 * HZ);
+		if (ret == 0)
+			DRM_ERROR("[CRTC:%d:%s] flip_done timed out\n",
+				  crtc->base.id, crtc->name);
+	}
+}
+EXPORT_SYMBOL(drm_atomic_helper_wait_for_flip_done);
+
+/**
  * drm_atomic_helper_commit_tail - commit atomic update to hardware
  * @old_state: atomic state object with old state structures
  *
diff --git a/include/drm/drm_atomic_helper.h b/include/drm/drm_atomic_helper.h
index f0a8678ae98e..7192e7ac117f 100644
--- a/include/drm/drm_atomic_helper.h
+++ b/include/drm/drm_atomic_helper.h
@@ -52,6 +52,9 @@ int drm_atomic_helper_wait_for_fences(struct drm_device *dev,
 void drm_atomic_helper_wait_for_vblanks(struct drm_device *dev,
 					struct drm_atomic_state *old_state);
 
+void drm_atomic_helper_wait_for_flip_done(struct drm_device *dev,
+					  struct drm_atomic_state *state);
+
 void
 drm_atomic_helper_update_legacy_modeset_state(struct drm_device *dev,
 					      struct drm_atomic_state *old_state);
-- 
2.7.4