drm/gem: Move drm_gem_fb_prepare_fb() to GEM atomic helpers

The function drm_gem_fb_prepare_fb() is a helper for atomic modesetting,
but currently located next to framebuffer helpers. Move it to GEM atomic
helpers, rename it slightly and adopt the drivers. Same for the rsp
simple-pipe helper.

Compile-tested with x86-64, aarch64 and arm. The patch is fairly large,
but there are no functional changes.

v3:
	* remove out-comented line in drm_gem_framebuffer_helper.h
	  (Maxime)
v2:
	* rename to drm_gem_plane_helper_prepare_fb() (Daniel)
	* add tutorial-style documentation

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210222141756.7864-1-tzimmermann@suse.de

5 files changed, 12 insertions, 11 deletions

diff --git a/include/drm/drm_gem_atomic_helper.h b/include/drm/drm_gem_atomic_helper.h
index 7abf40bdab3d..cfc5adee3d13 100644
--- a/include/drm/drm_gem_atomic_helper.h
+++ b/include/drm/drm_gem_atomic_helper.h
@@ -10,6 +10,14 @@
 struct drm_simple_display_pipe;
 
 /*
+ * Plane Helpers
+ */
+
+int drm_gem_plane_helper_prepare_fb(struct drm_plane *plane, struct drm_plane_state *state);
+int drm_gem_simple_display_pipe_prepare_fb(struct drm_simple_display_pipe *pipe,
+					   struct drm_plane_state *plane_state);
+
+/*
  * Helpers for planes with shadow buffers
  */
 
diff --git a/include/drm/drm_gem_framebuffer_helper.h b/include/drm/drm_gem_framebuffer_helper.h
index 6b013154911d..6bdffc7aa124 100644
--- a/include/drm/drm_gem_framebuffer_helper.h
+++ b/include/drm/drm_gem_framebuffer_helper.h
@@ -9,9 +9,6 @@ struct drm_framebuffer;
 struct drm_framebuffer_funcs;
 struct drm_gem_object;
 struct drm_mode_fb_cmd2;
-struct drm_plane;
-struct drm_plane_state;
-struct drm_simple_display_pipe;
 
 #define AFBC_VENDOR_AND_TYPE_MASK	GENMASK_ULL(63, 52)
 
@@ -44,8 +41,4 @@ int drm_gem_fb_afbc_init(struct drm_device *dev,
 			 const struct drm_mode_fb_cmd2 *mode_cmd,
 			 struct drm_afbc_framebuffer *afbc_fb);
 
-int drm_gem_fb_prepare_fb(struct drm_plane *plane,
-			  struct drm_plane_state *state);
-int drm_gem_fb_simple_display_pipe_prepare_fb(struct drm_simple_display_pipe *pipe,
-					      struct drm_plane_state *plane_state);
 #endif
diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h
index eb706342861d..df77ed843dd6 100644
--- a/include/drm/drm_modeset_helper_vtables.h
+++ b/include/drm/drm_modeset_helper_vtables.h
@@ -1179,7 +1179,7 @@ struct drm_plane_helper_funcs {
 	 * members in the plane structure.
 	 *
 	 * Drivers which always have their buffers pinned should use
-	 * drm_gem_fb_prepare_fb() for this hook.
+	 * drm_gem_plane_helper_prepare_fb() for this hook.
 	 *
 	 * The helpers will call @cleanup_fb with matching arguments for every
 	 * successful call to this hook.
diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h
index 95ab14a4336a..1294610e84f4 100644
--- a/include/drm/drm_plane.h
+++ b/include/drm/drm_plane.h
@@ -79,8 +79,8 @@ struct drm_plane_state {
 	 * preserved.
 	 *
 	 * Drivers should store any implicit fence in this from their
-	 * &drm_plane_helper_funcs.prepare_fb callback. See drm_gem_fb_prepare_fb()
-	 * and drm_gem_fb_simple_display_pipe_prepare_fb() for suitable helpers.
+	 * &drm_plane_helper_funcs.prepare_fb callback. See drm_gem_plane_helper_prepare_fb()
+	 * and drm_gem_simple_display_pipe_prepare_fb() for suitable helpers.
 	 */
 	struct dma_fence *fence;
 
diff --git a/include/drm/drm_simple_kms_helper.h b/include/drm/drm_simple_kms_helper.h
index 40b34573249f..ef9944e9c5fc 100644
--- a/include/drm/drm_simple_kms_helper.h
+++ b/include/drm/drm_simple_kms_helper.h
@@ -117,7 +117,7 @@ struct drm_simple_display_pipe_funcs {
 	 * more details.
 	 *
 	 * Drivers which always have their buffers pinned should use
-	 * drm_gem_fb_simple_display_pipe_prepare_fb() for this hook.
+	 * drm_gem_simple_display_pipe_prepare_fb() for this hook.
 	 */
 	int (*prepare_fb)(struct drm_simple_display_pipe *pipe,
 			  struct drm_plane_state *plane_state);