v4.19.13 snapshot.
diff --git a/include/linux/clkdev.h b/include/linux/clkdev.h
new file mode 100644
index 0000000..4890ff0
--- /dev/null
+++ b/include/linux/clkdev.h
@@ -0,0 +1,55 @@
+/*
+ * include/linux/clkdev.h
+ *
+ * Copyright (C) 2008 Russell King.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Helper for the clk API to assist looking up a struct clk.
+ */
+#ifndef __CLKDEV_H
+#define __CLKDEV_H
+
+#include <linux/slab.h>
+
+struct clk;
+struct clk_hw;
+struct device;
+
+struct clk_lookup {
+ struct list_head node;
+ const char *dev_id;
+ const char *con_id;
+ struct clk *clk;
+ struct clk_hw *clk_hw;
+};
+
+#define CLKDEV_INIT(d, n, c) \
+ { \
+ .dev_id = d, \
+ .con_id = n, \
+ .clk = c, \
+ }
+
+struct clk_lookup *clkdev_alloc(struct clk *clk, const char *con_id,
+ const char *dev_fmt, ...) __printf(3, 4);
+struct clk_lookup *clkdev_hw_alloc(struct clk_hw *hw, const char *con_id,
+ const char *dev_fmt, ...) __printf(3, 4);
+
+void clkdev_add(struct clk_lookup *cl);
+void clkdev_drop(struct clk_lookup *cl);
+
+struct clk_lookup *clkdev_create(struct clk *clk, const char *con_id,
+ const char *dev_fmt, ...) __printf(3, 4);
+struct clk_lookup *clkdev_hw_create(struct clk_hw *hw, const char *con_id,
+ const char *dev_fmt, ...) __printf(3, 4);
+
+void clkdev_add_table(struct clk_lookup *, size_t);
+int clk_add_alias(const char *, const char *, const char *, struct device *);
+
+int clk_register_clkdev(struct clk *, const char *, const char *);
+int clk_hw_register_clkdev(struct clk_hw *, const char *, const char *);
+
+#endif