Merge "drm/displayid: Iterate over all DisplayID blocks"

1 files changed, 21 insertions, 13 deletions

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 909f560016ad..4679c7dd6e1b 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -4128,19 +4128,27 @@ static int drm_parse_display_id(struct drm_connector *connector,
 	if (ret)
 		return ret;
 
-	block = (struct displayid_block *)&displayid[idx + 4];
-	DRM_DEBUG_KMS("block id %d, rev %d, len %d\n",
-		      block->tag, block->rev, block->num_bytes);
-
-	switch (block->tag) {
-	case DATA_BLOCK_TILED_DISPLAY:
-		ret = drm_parse_tiled_block(connector, block);
-		if (ret)
-			return ret;
-		break;
-	default:
-		printk("unknown displayid tag %d\n", block->tag);
-		break;
+	idx += sizeof(struct displayid_hdr);
+	while (block = (struct displayid_block *)&displayid[idx],
+	       idx + sizeof(struct displayid_block) <= length &&
+	       idx + sizeof(struct displayid_block) +
+		   block->num_bytes <= length &&
+	       block->num_bytes > 0) {
+		idx += block->num_bytes + sizeof(struct displayid_block);
+		DRM_DEBUG_KMS("block id 0x%x, rev %d, len %d\n",
+			      block->tag, block->rev, block->num_bytes);
+
+		switch (block->tag) {
+		case DATA_BLOCK_TILED_DISPLAY:
+			ret = drm_parse_tiled_block(connector, block);
+			if (ret)
+				return ret;
+			break;
+		default:
+			DRM_DEBUG_KMS("found DisplayID tag 0x%x, unhandled\n",
+						  block->tag);
+			break;
+		}
 	}
 	return 0;
 }