[PATCH 1/5] drm/plane: Pass old state to ->atomic_update()

[Thierry Reding]

From: Thierry Reding <treding at nvidia.com>

In most situations it will be useful to have the old state passed to the
->atomic_update() callback. For example if a plane is being disabled the
new state's .crtc field will be NULL, but some drivers may rely on this
field to program the CRTCs registers.

Signed-off-by: Thierry Reding <treding at nvidia.com>
---
Note that I based this patch on a local tree which has Daniel's Exynos
prototype conversion, so the Exynos specific parts may not apply to
anything else. I can respin if that's a problem.

 drivers/gpu/drm/drm_atomic_helper.c       | 4 +++-
 drivers/gpu/drm/drm_plane_helper.c        | 2 +-
 drivers/gpu/drm/exynos/exynos_drm_plane.c | 3 ++-
 drivers/gpu/drm/msm/mdp/mdp4/mdp4_plane.c | 3 ++-
 include/drm/drm_plane_helper.h            | 3 ++-
 5 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 690360038dc1..d55f4d0ce990 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -1011,6 +1011,7 @@ void drm_atomic_helper_commit_planes(struct drm_device *dev,
 	for (i = 0; i < nplanes; i++) {
 		struct drm_plane_helper_funcs *funcs;
 		struct drm_plane *plane = old_state->planes[i];
+		struct drm_plane_state *state = old_state->plane_states[i];
 
 		if (!plane)
 			continue;
@@ -1020,7 +1021,8 @@ void drm_atomic_helper_commit_planes(struct drm_device *dev,
 		if (!funcs || !funcs->atomic_update)
 			continue;
 
-		funcs->atomic_update(plane);
+		/* NOTE: state is the old state here. */
+		funcs->atomic_update(plane, state);
 	}
 
 	for (i = 0; i < ncrtcs; i++) {
diff --git a/drivers/gpu/drm/drm_plane_helper.c b/drivers/gpu/drm/drm_plane_helper.c
index 2dd30518f9a2..aa399db5d36d 100644
--- a/drivers/gpu/drm/drm_plane_helper.c
+++ b/drivers/gpu/drm/drm_plane_helper.c
@@ -443,7 +443,7 @@ int drm_plane_helper_commit(struct drm_plane *plane,
 			crtc_funcs[i]->atomic_begin(crtc[i]);
 	}
 
-	plane_funcs->atomic_update(plane);
+	plane_funcs->atomic_update(plane, plane_state);
 
 	for (i = 0; i < 2; i++) {
 		if (crtc_funcs[i] && crtc_funcs[i]->atomic_flush)
diff --git a/drivers/gpu/drm/exynos/exynos_drm_plane.c b/drivers/gpu/drm/exynos/exynos_drm_plane.c
index c218f7f5a5e5..b903937204a3 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_plane.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_plane.c
@@ -311,7 +311,8 @@ static int exynos_plane_atomic_check(struct drm_plane *plane,
 	return 0;
 }
 
-static void exynos_plane_atomic_update(struct drm_plane *plane)
+static void exynos_plane_atomic_update(struct drm_plane *plane,
+				       struct drm_plane_state *old_state)
 {
 	struct exynos_plane *exynos_plane = to_exynos_plane(plane);
 	int ret;
diff --git a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_plane.c b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_plane.c
index 76d0a40c7138..1e5ebe83647d 100644
--- a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_plane.c
+++ b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_plane.c
@@ -107,7 +107,8 @@ static int mdp4_plane_atomic_check(struct drm_plane *plane,
 	return 0;
 }
 
-static void mdp4_plane_atomic_update(struct drm_plane *plane)
+static void mdp4_plane_atomic_update(struct drm_plane *plane,
+				     struct drm_plane_state *old_state)
 {
 	struct drm_plane_state *state = plane->state;
 	int ret;
diff --git a/include/drm/drm_plane_helper.h b/include/drm/drm_plane_helper.h
index 00ad3b3c5324..d3122cd0609b 100644
--- a/include/drm/drm_plane_helper.h
+++ b/include/drm/drm_plane_helper.h
@@ -59,7 +59,8 @@ struct drm_plane_helper_funcs {
 
 	int (*atomic_check)(struct drm_plane *plane,
 			    struct drm_plane_state *state);
-	void (*atomic_update)(struct drm_plane *plane);
+	void (*atomic_update)(struct drm_plane *plane,
+			      struct drm_plane_state *old_state);
 };
 
 static inline void drm_plane_helper_add(struct drm_plane *plane,
-- 
2.1.3