clk: add helper functions clk_prepare_enable and clk_disable_unprepare

It's for migrating to generic clk framework API.

The helper functions  help cases clk_enable/clk_disable is used
in non-atomic context.
For example, Call clk_enable in probe and clk_disable in remove.

Signed-off-by: Richard Zhao <richard.zhao@linaro.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
This commit is contained in:
Richard Zhao 2011-11-15 14:47:56 +08:00 committed by Shawn Guo
parent 384703b8e6
commit 42c5d52f2b

View File

@ -107,6 +107,28 @@ static inline void clk_unprepare(struct clk *clk)
}
#endif
/* clk_prepare_enable helps cases using clk_enable in non-atomic context. */
static inline int clk_prepare_enable(struct clk *clk)
{
int ret;
ret = clk_prepare(clk);
if (ret)
return ret;
ret = clk_enable(clk);
if (ret)
clk_unprepare(clk);
return ret;
}
/* clk_disable_unprepare helps cases using clk_disable in non-atomic context. */
static inline void clk_disable_unprepare(struct clk *clk)
{
clk_disable(clk);
clk_unprepare(clk);
}
/**
* clk_get_rate - obtain the current clock rate (in Hz) for a clock source.
* This is only valid once the clock source has been enabled.