diff options
Diffstat (limited to 'include/linux/clk.h')
| -rw-r--r-- | include/linux/clk.h | 189 |
1 files changed, 149 insertions, 40 deletions
diff --git a/include/linux/clk.h b/include/linux/clk.h index 18b7b95a8253..562859ee24f4 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -172,6 +172,39 @@ int clk_get_scaled_duty_cycle(struct clk *clk, unsigned int scale); */ bool clk_is_match(const struct clk *p, const struct clk *q); +/** + * clk_rate_exclusive_get - get exclusivity over the rate control of a + * producer + * @clk: clock source + * + * This function allows drivers to get exclusive control over the rate of a + * provider. It prevents any other consumer to execute, even indirectly, + * opereation which could alter the rate of the provider or cause glitches + * + * If exlusivity is claimed more than once on clock, even by the same driver, + * the rate effectively gets locked as exclusivity can't be preempted. + * + * Must not be called from within atomic context. + * + * Returns success (0) or negative errno. + */ +int clk_rate_exclusive_get(struct clk *clk); + +/** + * clk_rate_exclusive_put - release exclusivity over the rate control of a + * producer + * @clk: clock source + * + * This function allows drivers to release the exclusivity it previously got + * from clk_rate_exclusive_get() + * + * The caller must balance the number of clk_rate_exclusive_get() and + * clk_rate_exclusive_put() calls. + * + * Must not be called from within atomic context. + */ +void clk_rate_exclusive_put(struct clk *clk); + #else static inline int clk_notifier_register(struct clk *clk, @@ -218,6 +251,13 @@ static inline bool clk_is_match(const struct clk *p, const struct clk *q) return p == q; } +static inline int clk_rate_exclusive_get(struct clk *clk) +{ + return 0; +} + +static inline void clk_rate_exclusive_put(struct clk *clk) {} + #endif /** @@ -419,6 +459,47 @@ int __must_check devm_clk_bulk_get_all(struct device *dev, struct clk *devm_clk_get(struct device *dev, const char *id); /** + * devm_clk_get_prepared - devm_clk_get() + clk_prepare() + * @dev: device for clock "consumer" + * @id: clock consumer ID + * + * Context: May sleep. + * + * Return: 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.) + * + * The returned clk (if valid) is prepared. Drivers must however assume + * that the clock is not enabled. + * + * The clock will automatically be unprepared and freed when the device + * is unbound from the bus. + */ +struct clk *devm_clk_get_prepared(struct device *dev, const char *id); + +/** + * devm_clk_get_enabled - devm_clk_get() + clk_prepare_enable() + * @dev: device for clock "consumer" + * @id: clock consumer ID + * + * Context: May sleep. + * + * Return: 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.) + * + * The returned clk (if valid) is prepared and enabled. + * + * The clock will automatically be disabled, unprepared and freed + * when the device is unbound from the bus. + */ +struct clk *devm_clk_get_enabled(struct device *dev, const char *id); + +/** * devm_clk_get_optional - lookup and obtain a managed reference to an optional * clock producer. * @dev: device for clock "consumer" @@ -430,53 +511,65 @@ struct clk *devm_clk_get(struct device *dev, const char *id); struct clk *devm_clk_get_optional(struct device *dev, const char *id); /** - * devm_get_clk_from_child - lookup and obtain a managed reference to a - * clock producer from child node. + * devm_clk_get_optional_prepared - devm_clk_get_optional() + clk_prepare() * @dev: device for clock "consumer" - * @np: pointer to clock consumer node - * @con_id: clock consumer ID + * @id: clock consumer ID * - * This function parses the clocks, and uses them to look up the - * struct clk from the registered list of clock providers by using - * @np and @con_id + * Context: May sleep. * - * The clock will automatically be freed when the device is unbound - * from the bus. + * Return: 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. If no such clk is found, it returns NULL + * which serves as a dummy clk. That's the only difference compared + * to devm_clk_get_prepared(). + * + * The returned clk (if valid) is prepared. Drivers must however + * assume that the clock is not enabled. + * + * The clock will automatically be unprepared and freed when the + * device is unbound from the bus. */ -struct clk *devm_get_clk_from_child(struct device *dev, - struct device_node *np, const char *con_id); +struct clk *devm_clk_get_optional_prepared(struct device *dev, const char *id); + /** - * clk_rate_exclusive_get - get exclusivity over the rate control of a - * producer - * @clk: clock source + * devm_clk_get_optional_enabled - devm_clk_get_optional() + + * clk_prepare_enable() + * @dev: device for clock "consumer" + * @id: clock consumer ID * - * This function allows drivers to get exclusive control over the rate of a - * provider. It prevents any other consumer to execute, even indirectly, - * opereation which could alter the rate of the provider or cause glitches + * Context: May sleep. * - * If exlusivity is claimed more than once on clock, even by the same driver, - * the rate effectively gets locked as exclusivity can't be preempted. + * Return: 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. If no such clk is found, it returns NULL + * which serves as a dummy clk. That's the only difference compared + * to devm_clk_get_enabled(). * - * Must not be called from within atomic context. + * The returned clk (if valid) is prepared and enabled. * - * Returns success (0) or negative errno. + * The clock will automatically be disabled, unprepared and freed + * when the device is unbound from the bus. */ -int clk_rate_exclusive_get(struct clk *clk); +struct clk *devm_clk_get_optional_enabled(struct device *dev, const char *id); /** - * clk_rate_exclusive_put - release exclusivity over the rate control of a - * producer - * @clk: clock source - * - * This function allows drivers to release the exclusivity it previously got - * from clk_rate_exclusive_get() + * devm_get_clk_from_child - lookup and obtain a managed reference to a + * clock producer from child node. + * @dev: device for clock "consumer" + * @np: pointer to clock consumer node + * @con_id: clock consumer ID * - * The caller must balance the number of clk_rate_exclusive_get() and - * clk_rate_exclusive_put() calls. + * This function parses the clocks, and uses them to look up the + * struct clk from the registered list of clock providers by using + * @np and @con_id * - * Must not be called from within atomic context. + * The clock will automatically be freed when the device is unbound + * from the bus. */ -void clk_rate_exclusive_put(struct clk *clk); +struct clk *devm_get_clk_from_child(struct device *dev, + struct device_node *np, const char *con_id); /** * clk_enable - inform the system when the clock source should be running. @@ -770,12 +863,36 @@ static inline struct clk *devm_clk_get(struct device *dev, const char *id) return NULL; } +static inline struct clk *devm_clk_get_prepared(struct device *dev, + const char *id) +{ + return NULL; +} + +static inline struct clk *devm_clk_get_enabled(struct device *dev, + const char *id) +{ + return NULL; +} + static inline struct clk *devm_clk_get_optional(struct device *dev, const char *id) { return NULL; } +static inline struct clk *devm_clk_get_optional_prepared(struct device *dev, + const char *id) +{ + return NULL; +} + +static inline struct clk *devm_clk_get_optional_enabled(struct device *dev, + const char *id) +{ + return NULL; +} + static inline int __must_check devm_clk_bulk_get(struct device *dev, int num_clks, struct clk_bulk_data *clks) { @@ -809,14 +926,6 @@ static inline void clk_bulk_put_all(int num_clks, struct clk_bulk_data *clks) {} static inline void devm_clk_put(struct device *dev, struct clk *clk) {} - -static inline int clk_rate_exclusive_get(struct clk *clk) -{ - return 0; -} - -static inline void clk_rate_exclusive_put(struct clk *clk) {} - static inline int clk_enable(struct clk *clk) { return 0; |