drm/rcar-du/crc: Implement get_crc_sources callback

This patch implements get_crc_sources callback, which returns list of
all the crc sources supported by driver in current platform.

Changes Since V1:
 - move sources list per-crtc
 - init sources-list only for gen3
Changes Since V2:
 - Adopt to driver style
 - Address other review comments from Laurent Pinchart
Changes Since V3/4/5: (Laurent Pinchart review)
 - s/rcar_du_crtc_crc_sources_list_init/rcar_du_crtc_crc_init
 - s/rcar_du_crtc_crc_sources_list_uninit/rcar_du_crtc_crc_cleanup
 - other cleanup

Signed-off-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Cc: dri-devel@lists.freedesktop.org
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180808152630.6563-1-mahesh1.kumar@intel.com

drivers/gpu/drm/rcar-du/rcar_du_crtc.c

@@ -691,6 +691,65 @@ static const struct drm_crtc_helper_funcs crtc_helper_funcs = {
 	.atomic_disable = rcar_du_crtc_atomic_disable,
 };
 
+static void rcar_du_crtc_crc_init(struct rcar_du_crtc *rcrtc)
+{
+	struct rcar_du_device *rcdu = rcrtc->group->dev;
+	const char **sources;
+	unsigned int count;
+	int i = -1;
+
+	/* CRC available only on Gen3 HW. */
+	if (rcdu->info->gen < 3)
+		return;
+
+	/* Reserve 1 for "auto" source. */
+	count = rcrtc->vsp->num_planes + 1;
+
+	sources = kmalloc_array(count, sizeof(*sources), GFP_KERNEL);
+	if (!sources)
+		return;
+
+	sources[0] = kstrdup("auto", GFP_KERNEL);
+	if (!sources[0])
+		goto error;
+
+	for (i = 0; i < rcrtc->vsp->num_planes; ++i) {
+		struct drm_plane *plane = &rcrtc->vsp->planes[i].plane;
+		char name[16];
+
+		sprintf(name, "plane%u", plane->base.id);
+		sources[i + 1] = kstrdup(name, GFP_KERNEL);
+		if (!sources[i + 1])
+			goto error;
+	}
+
+	rcrtc->sources = sources;
+	rcrtc->sources_count = count;
+	return;
+
+error:
+	while (i >= 0) {
+		kfree(sources[i]);
+		i--;
+	}
+	kfree(sources);
+}
+
+static void rcar_du_crtc_crc_cleanup(struct rcar_du_crtc *rcrtc)
+{
+	unsigned int i;
+
+	if (!rcrtc->sources)
+		return;
+
+	for (i = 0; i < rcrtc->sources_count; i++)
+		kfree(rcrtc->sources[i]);
+	kfree(rcrtc->sources);
+
+	rcrtc->sources = NULL;
+	rcrtc->sources_count = 0;
+}
+
 static struct drm_crtc_state *
 rcar_du_crtc_atomic_duplicate_state(struct drm_crtc *crtc)
 {
@@ -717,6 +776,15 @@ static void rcar_du_crtc_atomic_destroy_state(struct drm_crtc *crtc,
 	kfree(to_rcar_crtc_state(state));
 }
 
+static void rcar_du_crtc_cleanup(struct drm_crtc *crtc)
+{
+	struct rcar_du_crtc *rcrtc = to_rcar_crtc(crtc);
+
+	rcar_du_crtc_crc_cleanup(rcrtc);
+
+	return drm_crtc_cleanup(crtc);
+}
+
 static void rcar_du_crtc_reset(struct drm_crtc *crtc)
 {
 	struct rcar_du_crtc_state *state;
@@ -809,6 +877,15 @@ static int rcar_du_crtc_verify_crc_source(struct drm_crtc *crtc,
 	return 0;
 }
 
+const char *const *rcar_du_crtc_get_crc_sources(struct drm_crtc *crtc,
+						size_t *count)
+{
+	struct rcar_du_crtc *rcrtc = to_rcar_crtc(crtc);
+
+	*count = rcrtc->sources_count;
+	return rcrtc->sources;
+}
+
 static int rcar_du_crtc_set_crc_source(struct drm_crtc *crtc,
 				       const char *source_name,
 				       size_t *values_cnt)
@@ -881,7 +958,7 @@ static const struct drm_crtc_funcs crtc_funcs_gen2 = {
 
 static const struct drm_crtc_funcs crtc_funcs_gen3 = {
 	.reset = rcar_du_crtc_reset,
-	.destroy = drm_crtc_cleanup,
+	.destroy = rcar_du_crtc_cleanup,
 	.set_config = drm_atomic_helper_set_config,
 	.page_flip = drm_atomic_helper_page_flip,
 	.atomic_duplicate_state = rcar_du_crtc_atomic_duplicate_state,
@@ -890,6 +967,7 @@ static const struct drm_crtc_funcs crtc_funcs_gen3 = {
 	.disable_vblank = rcar_du_crtc_disable_vblank,
 	.set_crc_source = rcar_du_crtc_set_crc_source,
 	.verify_crc_source = rcar_du_crtc_verify_crc_source,
+	.get_crc_sources = rcar_du_crtc_get_crc_sources,
 };
 
 /* -----------------------------------------------------------------------------
@@ -1028,5 +1106,7 @@ int rcar_du_crtc_create(struct rcar_du_group *rgrp, unsigned int swindex,
 		return ret;
 	}
 
+	rcar_du_crtc_crc_init(rcrtc);
+
 	return 0;
 }

drivers/gpu/drm/rcar-du/rcar_du_crtc.h

@@ -67,6 +67,9 @@ struct rcar_du_crtc {
 	struct rcar_du_group *group;
 	struct rcar_du_vsp *vsp;
 	unsigned int vsp_pipe;
+
+	const char *const *sources;
+	unsigned int sources_count;
 };
 
 #define to_rcar_crtc(c)	container_of(c, struct rcar_du_crtc, crtc)