+/**
+ * drm_atomic_replace_property_blob - replace a blob property
+ * @blob: a pointer to the member blob to be replaced
+ * @new_blob: the new blob to replace with
+ * @expected_size: the expected size of the new blob
+ * @replaced: whether the blob has been replaced
+ *
+ * RETURNS:
+ * Zero on success, error code on failure
+ */
+static void
+drm_atomic_replace_property_blob(struct drm_property_blob **blob,
+ struct drm_property_blob *new_blob,
+ bool *replaced)
+{
+ struct drm_property_blob *old_blob = *blob;
+
+ if (old_blob == new_blob)
+ return;
+
+ if (old_blob)
+ drm_property_unreference_blob(old_blob);
+ if (new_blob)
+ drm_property_reference_blob(new_blob);
+ *blob = new_blob;
+ *replaced = true;
+
+ return;
+}
+
+int
+drm_atomic_replace_property_blob_from_id(struct drm_crtc *crtc,
+ struct drm_property_blob **blob,
+ uint64_t blob_id,
+ ssize_t expected_size,
+ bool *replaced)
+{
+ struct drm_device *dev = crtc->dev;
+ struct drm_property_blob *new_blob = NULL;
+
+ if (blob_id != 0) {
+ new_blob = drm_property_lookup_blob(dev, blob_id);
+ if (new_blob == NULL)
+ return -EINVAL;
+ if (expected_size > 0 && expected_size != new_blob->length)
+ return -EINVAL;
+ }
+
+ drm_atomic_replace_property_blob(blob, new_blob, replaced);
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_atomic_replace_property_blob_from_id);
+