compositor-drm: Simplify drm_sprite_crtc_supported

No need to walk the CRTC list every time looking for CRTC indices, when we
already have the CRTC index stashed away. Taking the plane as an argument
also simplifies things a little for callers, and future-proofs for a
potential future KMS API which passes a list of supported CRTC IDs rather
than a bitmask of supported CRTC indices.

Signed-off-by: Daniel Stone <daniels@collabora.com>
Reviewed-by: Armin Krezović <krezovic.armin@gmail.com>

Differential Revision: https://phabricator.freedesktop.org/D1407

libweston/compositor-drm.c

@@ -93,8 +93,6 @@ struct drm_backend {
 		char *filename;
 	} drm;
 	struct gbm_device *gbm;
-	uint32_t *crtcs;
-	int num_crtcs;
 	uint32_t crtc_allocator;
 	uint32_t connector_allocator;
 	struct wl_listener session_listener;
@@ -236,21 +234,9 @@ static void
 drm_output_update_msc(struct drm_output *output, unsigned int seq);
 
 static int
-drm_sprite_crtc_supported(struct drm_output *output, uint32_t supported)
+drm_sprite_crtc_supported(struct drm_output *output, struct drm_sprite *sprite)
 {
-	struct weston_compositor *ec = output->base.compositor;
-	struct drm_backend *b = to_drm_backend(ec);
-	int crtc;
-
-	for (crtc = 0; crtc < b->num_crtcs; crtc++) {
-		if (b->crtcs[crtc] != output->crtc_id)
-			continue;
-
-		if (supported & (1 << crtc))
-			return -1;
-	}
-
-	return 0;
+	return !!(sprite->possible_crtcs & (1 << output->pipe));
 }
 
 static void
@@ -718,7 +704,7 @@ drm_output_repaint(struct weston_output *output_base,
 		};
 
 		if ((!s->current && !s->next) ||
-		    !drm_sprite_crtc_supported(output, s->possible_crtcs))
+		    !drm_sprite_crtc_supported(output, s))
 			continue;
 
 		if (s->next && !backend->sprites_hidden)
@@ -993,7 +979,7 @@ drm_output_prepare_overlay_view(struct drm_output *output,
 		return NULL;
 
 	wl_list_for_each(s, &b->sprite_list, link) {
-		if (!drm_sprite_crtc_supported(output, s->possible_crtcs))
+		if (!drm_sprite_crtc_supported(output, s))
 			continue;
 
 		if (!s->next) {
@@ -2654,20 +2640,11 @@ create_outputs(struct drm_backend *b, uint32_t option_connector,
 		return -1;
 	}
 
-	b->crtcs = calloc(resources->count_crtcs, sizeof(uint32_t));
-	if (!b->crtcs) {
-		drmModeFreeResources(resources);
-		return -1;
-	}
-
 	b->min_width  = resources->min_width;
 	b->max_width  = resources->max_width;
 	b->min_height = resources->min_height;
 	b->max_height = resources->max_height;
 
-	b->num_crtcs = resources->count_crtcs;
-	memcpy(b->crtcs, resources->crtcs, sizeof(uint32_t) * b->num_crtcs);
-
 	for (i = 0; i < resources->count_connectors; i++) {
 		connector = drmModeGetConnector(b->drm.fd,
 						resources->connectors[i]);