drm/sti: plane: Remove redundant zpos initialisation

The sti KMS driver will call drm_plane_create_zpos_property() with an
init value depending on the plane type.

Since the initial value wasn't carried over in the state, the driver had
to set it again in sti_plane_reset().
However, the helpers have been adjusted to set it properly at reset, so
this is not needed anymore.
Reviewed-by: Alain Volmat <alain.volmat@foss.st.com>
Reviewed-by: Philippe Cornu <philippe.cornu@foss.st.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220221095918.18763-17-maxime@cerno.tech

drivers/gpu/drm/sti/sti_cursor.c

@@ -351,7 +351,7 @@ static const struct drm_plane_funcs sti_cursor_plane_helpers_funcs = {
 	.update_plane = drm_atomic_helper_update_plane,
 	.disable_plane = drm_atomic_helper_disable_plane,
 	.destroy = drm_plane_cleanup,
-	.reset = sti_plane_reset,
+	.reset = drm_atomic_helper_plane_reset,
 	.atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
 	.atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
 	.late_register = sti_cursor_late_register,

drivers/gpu/drm/sti/sti_gdp.c

@@ -905,7 +905,7 @@ static const struct drm_plane_funcs sti_gdp_plane_helpers_funcs = {
 	.update_plane = drm_atomic_helper_update_plane,
 	.disable_plane = drm_atomic_helper_disable_plane,
 	.destroy = drm_plane_cleanup,
-	.reset = sti_plane_reset,
+	.reset = drm_atomic_helper_plane_reset,
 	.atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
 	.atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
 	.late_register = sti_gdp_late_register,

drivers/gpu/drm/sti/sti_hqvdp.c

@@ -1283,7 +1283,7 @@ static const struct drm_plane_funcs sti_hqvdp_plane_helpers_funcs = {
 	.update_plane = drm_atomic_helper_update_plane,
 	.disable_plane = drm_atomic_helper_disable_plane,
 	.destroy = drm_plane_cleanup,
-	.reset = sti_plane_reset,
+	.reset = drm_atomic_helper_plane_reset,
 	.atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
 	.atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
 	.late_register = sti_hqvdp_late_register,

drivers/gpu/drm/sti/sti_plane.c

@@ -112,12 +112,6 @@ static int sti_plane_get_default_zpos(enum drm_plane_type type)
 	return 0;
 }
 
-void sti_plane_reset(struct drm_plane *plane)
-{
-	drm_atomic_helper_plane_reset(plane);
-	plane->state->zpos = sti_plane_get_default_zpos(plane->type);
-}
-
 static void sti_plane_attach_zorder_property(struct drm_plane *drm_plane,
 					     enum drm_plane_type type)
 {

drivers/gpu/drm/sti/sti_plane.h

@@ -81,5 +81,4 @@ void sti_plane_update_fps(struct sti_plane *plane,
 
 void sti_plane_init_property(struct sti_plane *plane,
 			     enum drm_plane_type type);
-void sti_plane_reset(struct drm_plane *plane);
 #endif