From a8a97db984bdc5e89d42e41891543d2daaf314cb Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Thu, 5 Apr 2012 11:42:09 +0100 Subject: ARM: 7376/1: clkdev: Implement managed clk_get() Allow clk API users to simplify their cleanup paths by providing a managed version of clk_get() and clk_put(). Signed-off-by: Mark Brown Signed-off-by: Russell King --- Documentation/driver-model/devres.txt | 4 ++++ drivers/clk/clkdev.c | 45 +++++++++++++++++++++++++++++++++++ include/linux/clk.h | 32 +++++++++++++++++++++++++ 3 files changed, 81 insertions(+) diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt index 2a596a4fc23e..9faac6ae3525 100644 --- a/Documentation/driver-model/devres.txt +++ b/Documentation/driver-model/devres.txt @@ -276,3 +276,7 @@ REGULATOR devm_regulator_get() devm_regulator_put() devm_regulator_bulk_get() + +CLOCK + devm_clk_get() + devm_clk_put() diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c index 6db161f64ae0..a9a113782821 100644 --- a/drivers/clk/clkdev.c +++ b/drivers/clk/clkdev.c @@ -89,6 +89,51 @@ 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(devm_clk_get); + +static int devm_clk_match(struct device *dev, void *res, void *data) +{ + struct clk **c = res; + if (!c || !*c) { + WARN_ON(!c || !*c); + return 0; + } + return *c == data; +} + +void devm_clk_put(struct device *dev, struct clk *clk) +{ + int ret; + + ret = devres_destroy(dev, devm_clk_release, devm_clk_match, clk); + + WARN_ON(ret); +} +EXPORT_SYMBOL(devm_clk_put); + void clkdev_add(struct clk_lookup *cl) { mutex_lock(&clocks_mutex); diff --git a/include/linux/clk.h b/include/linux/clk.h index b0252726df61..70cf722ac3af 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -100,6 +100,26 @@ 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 @@ -206,6 +226,18 @@ unsigned long clk_get_rate(struct clk *clk); */ void clk_put(struct clk *clk); +/** + * devm_clk_put - "free" a managed clock source + * @dev: device used to acuqire the clock + * @clk: clock source acquired with devm_clk_get() + * + * Note: drivers must ensure that all clk_enable calls made on this + * clock source are balanced by clk_disable calls prior to calling + * this function. + * + * clk_put should not be called from within interrupt context. + */ +void devm_clk_put(struct device *dev, struct clk *clk); /* * The remaining APIs are optional for machine class support. -- cgit v1.2.3-59-g8ed1b From 67b508715a61962f9b5b3ef3432e045a9cba4f1e Mon Sep 17 00:00:00 2001 From: viresh kumar Date: Thu, 19 Apr 2012 04:23:25 +0100 Subject: ARM: 7392/1: CLKDEV: Optimize clk_find() clk_find must return as soon as it gets the correct clock. Currently it check all clocks until it found a lookup with both dev_id and con_id matching. If only one of them is passed, then we don't actually need to wait for both of them to match. We can quit as soon as the requested id (dev_id or con_id) matches. Signed-off-by: Viresh Kumar Signed-off-by: Russell King --- drivers/clk/clkdev.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c index a9a113782821..d4a59931e75e 100644 --- a/drivers/clk/clkdev.c +++ b/drivers/clk/clkdev.c @@ -35,7 +35,12 @@ static DEFINE_MUTEX(clocks_mutex); static struct clk_lookup *clk_find(const char *dev_id, const char *con_id) { struct clk_lookup *p, *cl = NULL; - int match, best = 0; + int match, best_found = 0, best_possible = 0; + + if (dev_id) + best_possible += 2; + if (con_id) + best_possible += 1; list_for_each_entry(p, &clocks, node) { match = 0; @@ -50,10 +55,10 @@ static struct clk_lookup *clk_find(const char *dev_id, const char *con_id) match += 1; } - if (match > best) { + if (match > best_found) { cl = p; - if (match != 3) - best = match; + if (match != best_possible) + best_found = match; else break; } -- cgit v1.2.3-59-g8ed1b From e9d7f4065408e92338a41b809e437c6e043da090 Mon Sep 17 00:00:00 2001 From: Russell King Date: Wed, 2 May 2012 09:30:32 +0100 Subject: CLKDEV: provide helpers for common clock framework The common clock framework allocates clocks dynamically. Provide a set of helpers to streamline the clkdev registration of the clock lookups to avoid repetitive code sequences. Reviewed-by: Viresh Kumar Tested-by: Shawn Guo Signed-off-by: Russell King --- drivers/clk/clkdev.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++---- include/linux/clkdev.h | 3 ++ 2 files changed, 81 insertions(+), 6 deletions(-) diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c index d4a59931e75e..c535cf8c5770 100644 --- a/drivers/clk/clkdev.c +++ b/drivers/clk/clkdev.c @@ -166,8 +166,9 @@ struct clk_lookup_alloc { char con_id[MAX_CON_ID]; }; -struct clk_lookup * __init_refok -clkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, ...) +static struct clk_lookup * __init_refok +vclkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, + va_list ap) { struct clk_lookup_alloc *cla; @@ -182,16 +183,25 @@ clkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, ...) } if (dev_fmt) { - va_list ap; - - va_start(ap, dev_fmt); vscnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap); cla->cl.dev_id = cla->dev_id; - va_end(ap); } return &cla->cl; } + +struct clk_lookup * __init_refok +clkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, ...) +{ + struct clk_lookup *cl; + va_list ap; + + va_start(ap, dev_fmt); + cl = vclkdev_alloc(clk, con_id, dev_fmt, ap); + va_end(ap); + + return cl; +} EXPORT_SYMBOL(clkdev_alloc); int clk_add_alias(const char *alias, const char *alias_dev_name, char *id, @@ -223,3 +233,65 @@ void clkdev_drop(struct clk_lookup *cl) kfree(cl); } EXPORT_SYMBOL(clkdev_drop); + +/** + * clk_register_clkdev - register one clock lookup for a struct clk + * @clk: struct clk to associate with all clk_lookups + * @con_id: connection ID string on device + * @dev_id: format string describing device name + * + * con_id or dev_id may be NULL as a wildcard, just as in the rest of + * clkdev. + * + * To make things easier for mass registration, we detect error clks + * from a previous clk_register() call, and return the error code for + * those. This is to permit this function to be called immediately + * after clk_register(). + */ +int clk_register_clkdev(struct clk *clk, const char *con_id, + const char *dev_fmt, ...) +{ + struct clk_lookup *cl; + va_list ap; + + if (IS_ERR(clk)) + return PTR_ERR(clk); + + va_start(ap, dev_fmt); + cl = vclkdev_alloc(clk, con_id, dev_fmt, ap); + va_end(ap); + + if (!cl) + return -ENOMEM; + + clkdev_add(cl); + + return 0; +} + +/** + * clk_register_clkdevs - register a set of clk_lookup for a struct clk + * @clk: struct clk to associate with all clk_lookups + * @cl: array of clk_lookup structures with con_id and dev_id pre-initialized + * @num: number of clk_lookup structures to register + * + * To make things easier for mass registration, we detect error clks + * from a previous clk_register() call, and return the error code for + * those. This is to permit this function to be called immediately + * after clk_register(). + */ +int clk_register_clkdevs(struct clk *clk, struct clk_lookup *cl, size_t num) +{ + unsigned i; + + if (IS_ERR(clk)) + return PTR_ERR(clk); + + for (i = 0; i < num; i++, cl++) { + cl->clk = clk; + clkdev_add(cl); + } + + return 0; +} +EXPORT_SYMBOL(clk_register_clkdevs); diff --git a/include/linux/clkdev.h b/include/linux/clkdev.h index d9a4fd028c9d..a6a6f603103b 100644 --- a/include/linux/clkdev.h +++ b/include/linux/clkdev.h @@ -40,4 +40,7 @@ void clkdev_drop(struct clk_lookup *cl); void clkdev_add_table(struct clk_lookup *, size_t); int clk_add_alias(const char *, const char *, char *, struct device *); +int clk_register_clkdev(struct clk *, const char *, const char *, ...); +int clk_register_clkdevs(struct clk *, struct clk_lookup *, size_t); + #endif -- cgit v1.2.3-59-g8ed1b