Messages in this thread Patch in this message | | | From | Mark Brown <> | Subject | [PATCH 2/2] clkdev: Implement managed clk_get() | Date | Sun, 1 Apr 2012 12:32:40 +0100 |
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Allow clk API users to simplify their cleanup paths by providing a managed version of clk_get().
Due to the lack of a standard struct clk to look up the device from a managed clk_put() is not provided, it would be very unusual to use this function so it's not a big loss.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> --- Documentation/driver-model/devres.txt | 3 +++ drivers/clk/clkdev.c | 25 +++++++++++++++++++++++++ include/linux/clk.h | 20 ++++++++++++++++++++ 3 files changed, 48 insertions(+), 0 deletions(-)
diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt index 2a596a4..3a10848 100644 --- a/Documentation/driver-model/devres.txt +++ b/Documentation/driver-model/devres.txt @@ -276,3 +276,6 @@ REGULATOR devm_regulator_get() devm_regulator_put() devm_regulator_bulk_get() + +CLOCK + devm_clk_get() diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c index 6db161f..8af1d2c 100644 --- a/drivers/clk/clkdev.c +++ b/drivers/clk/clkdev.c @@ -89,6 +89,31 @@ void clk_put(struct clk *clk) } EXPORT_SYMBOL(clk_put); +static void devm_clk_release(struct device *dev, void *res) +{ + clk_put(*(struct clk **)res); +} + +struct clk *devm_clk_get(struct device *dev, const char *id) +{ + struct clk **ptr, *clk; + + ptr = devres_alloc(devm_clk_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + clk = clk_get(dev, id); + if (!IS_ERR(clk)) { + *ptr = clk; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return clk; +} +EXPORT_SYMBOL_GPL(devm_clk_get); + void clkdev_add(struct clk_lookup *cl) { mutex_lock(&clocks_mutex); diff --git a/include/linux/clk.h b/include/linux/clk.h index 4b27d15..fd96e4a 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -101,6 +101,26 @@ int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb); struct clk *clk_get(struct device *dev, const char *id); /** + * devm_clk_get - lookup and obtain a managed reference to a clock producer. + * @dev: device for clock "consumer" + * @id: clock comsumer ID + * + * Returns a struct clk corresponding to the clock producer, or + * valid IS_ERR() condition containing errno. The implementation + * uses @dev and @id to determine the clock consumer, and thereby + * the clock producer. (IOW, @id may be identical strings, but + * clk_get may return different clock producers depending on @dev.) + * + * Drivers must assume that the clock source is not enabled. + * + * devm_clk_get should not be called from within interrupt context. + * + * The clock will automatically be freed when the device is unbound + * from the bus. + */ +struct clk *devm_clk_get(struct device *dev, const char *id); + +/** * clk_prepare - prepare a clock source * @clk: clock source * -- 1.7.9.1
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