clk: Provide not locked variant of of_clk_get_from_provider()

Add helper functions for the of_clk_providers list locking and
an unlocked variant of of_clk_get_from_provider().
These functions are intended to be used in the clkdev to avoid
race condition in the device tree based clock look up in clk_get().

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 16 insertions, 0 deletions

diff --git a/drivers/clk/clk.h b/drivers/clk/clk.h
new file mode 100644
index 000000000000..795cc9f0dac0
--- /dev/null
+++ b/drivers/clk/clk.h
@@ -0,0 +1,16 @@
+/*
+ * linux/drivers/clk/clk.h
+ *
+ * Copyright (C) 2013 Samsung Electronics Co., Ltd.
+ * Sylwester Nawrocki <s.nawrocki@samsung.com>
+ *
+ * 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.
+ */
+
+#if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK)
+struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec);
+void of_clk_lock(void);
+void of_clk_unlock(void);
+#endif