[PATCH v4 2/7] drm/atomic-helper: Add format-conversion state to shadow-plane state

[Thomas Zimmermann <tzimmermann@xxxxxxx>]

Store an instance of struct drm_format_conv_state in the shadow-plane
state struct drm_shadow_plane_state. Many drivers with shadow planes
use DRM's format helpers to copy or convert the framebuffer data to
backing storage in the scanout buffer. The shadow plane provides the
necessary state and manages the conversion's intermediate buffer memory.

Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
---
 drivers/gpu/drm/drm_gem_atomic_helper.c |  9 +++++++++
 include/drm/drm_gem_atomic_helper.h     | 10 ++++++++++
 2 files changed, 19 insertions(+)

diff --git a/drivers/gpu/drm/drm_gem_atomic_helper.c b/drivers/gpu/drm/drm_gem_atomic_helper.c
index 5d4b9cd077f7a..e440f458b6633 100644
--- a/drivers/gpu/drm/drm_gem_atomic_helper.c
+++ b/drivers/gpu/drm/drm_gem_atomic_helper.c
@@ -218,7 +218,14 @@ void
 __drm_gem_duplicate_shadow_plane_state(struct drm_plane *plane,
 				       struct drm_shadow_plane_state *new_shadow_plane_state)
 {
+	struct drm_plane_state *plane_state = plane->state;
+	struct drm_shadow_plane_state *shadow_plane_state =
+		to_drm_shadow_plane_state(plane_state);
+
 	__drm_atomic_helper_plane_duplicate_state(plane, &new_shadow_plane_state->base);
+
+	drm_format_conv_state_copy(&shadow_plane_state->fmtcnv_state,
+				   &new_shadow_plane_state->fmtcnv_state);
 }
 EXPORT_SYMBOL(__drm_gem_duplicate_shadow_plane_state);
 
@@ -266,6 +273,7 @@ EXPORT_SYMBOL(drm_gem_duplicate_shadow_plane_state);
  */
 void __drm_gem_destroy_shadow_plane_state(struct drm_shadow_plane_state *shadow_plane_state)
 {
+	drm_format_conv_state_release(&shadow_plane_state->fmtcnv_state);
 	__drm_atomic_helper_plane_destroy_state(&shadow_plane_state->base);
 }
 EXPORT_SYMBOL(__drm_gem_destroy_shadow_plane_state);
@@ -302,6 +310,7 @@ void __drm_gem_reset_shadow_plane(struct drm_plane *plane,
 				  struct drm_shadow_plane_state *shadow_plane_state)
 {
 	__drm_atomic_helper_plane_reset(plane, &shadow_plane_state->base);
+	drm_format_conv_state_init(&shadow_plane_state->fmtcnv_state);
 }
 EXPORT_SYMBOL(__drm_gem_reset_shadow_plane);
 
diff --git a/include/drm/drm_gem_atomic_helper.h b/include/drm/drm_gem_atomic_helper.h
index 40b8b039518e0..3e01c619a25e0 100644
--- a/include/drm/drm_gem_atomic_helper.h
+++ b/include/drm/drm_gem_atomic_helper.h
@@ -5,6 +5,7 @@
 
 #include <linux/iosys-map.h>
 
+#include <drm/drm_format_helper.h>
 #include <drm/drm_fourcc.h>
 #include <drm/drm_plane.h>
 
@@ -49,6 +50,15 @@ struct drm_shadow_plane_state {
 	/** @base: plane state */
 	struct drm_plane_state base;
 
+	/**
+	 * @fmtcnv_state: Format-conversion state
+	 *
+	 * Per-plane state for format conversion.
+	 * Flags for copying shadow buffers into backend storage. Also holds
+	 * temporary storage for format conversion.
+	 */
+	struct drm_format_conv_state fmtcnv_state;
+
 	/* Transitional state - do not export or duplicate */
 
 	/**
-- 
2.42.0