From abae8e57e49aa75f6db76aa866c775721523908f Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Fri, 20 May 2022 09:57:35 +0200 Subject: clk: generalize devm_clk_get() a bit MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Allow to add an exit hook to devm managed clocks. Also use clk_get_optional() in devm_clk_get_optional instead of open coding it. The generalisation will be used in the next commit to add some more devm_clk helpers. Reviewed-by: Jonathan Cameron Reviewed-by: Alexandru Ardelean Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20220520075737.758761-3-u.kleine-koenig@pengutronix.de Signed-off-by: Stephen Boyd --- drivers/clk/clk-devres.c | 66 +++++++++++++++++++++++++++++++++++------------- 1 file changed, 49 insertions(+), 17 deletions(-) (limited to 'drivers/clk/clk-devres.c') diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c index f9d5b7334341..c822f4ef1584 100644 --- a/drivers/clk/clk-devres.c +++ b/drivers/clk/clk-devres.c @@ -4,39 +4,71 @@ #include #include +struct devm_clk_state { + struct clk *clk; + void (*exit)(struct clk *clk); +}; + static void devm_clk_release(struct device *dev, void *res) { - clk_put(*(struct clk **)res); + struct devm_clk_state *state = *(struct devm_clk_state **)res; + + if (state->exit) + state->exit(state->clk); + + clk_put(state->clk); } -struct clk *devm_clk_get(struct device *dev, const char *id) +static struct clk *__devm_clk_get(struct device *dev, const char *id, + struct clk *(*get)(struct device *dev, const char *id), + int (*init)(struct clk *clk), + void (*exit)(struct clk *clk)) { - struct clk **ptr, *clk; + struct devm_clk_state *state; + struct clk *clk; + int ret; - ptr = devres_alloc(devm_clk_release, sizeof(*ptr), GFP_KERNEL); - if (!ptr) + state = devres_alloc(devm_clk_release, sizeof(*state), GFP_KERNEL); + if (!state) return ERR_PTR(-ENOMEM); - clk = clk_get(dev, id); - if (!IS_ERR(clk)) { - *ptr = clk; - devres_add(dev, ptr); - } else { - devres_free(ptr); + clk = get(dev, id); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + goto err_clk_get; } + if (init) { + ret = init(clk); + if (ret) + goto err_clk_init; + } + + state->clk = clk; + state->exit = exit; + + devres_add(dev, state); + return clk; + +err_clk_init: + + clk_put(clk); +err_clk_get: + + devres_free(state); + return ERR_PTR(ret); +} + +struct clk *devm_clk_get(struct device *dev, const char *id) +{ + return __devm_clk_get(dev, id, clk_get, NULL, NULL); } EXPORT_SYMBOL(devm_clk_get); struct clk *devm_clk_get_optional(struct device *dev, const char *id) { - struct clk *clk = devm_clk_get(dev, id); - - if (clk == ERR_PTR(-ENOENT)) - return NULL; - - return clk; + return __devm_clk_get(dev, id, clk_get_optional, NULL, NULL); } EXPORT_SYMBOL(devm_clk_get_optional); -- cgit v1.2.3 From 7ef9651e9792b08eb310c6beb202cbc947f43cab Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Fri, 20 May 2022 09:57:36 +0200 Subject: clk: Provide new devm_clk helpers for prepared and enabled clocks MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When a driver keeps a clock prepared (or enabled) during the whole lifetime of the driver, these helpers allow to simplify the drivers. Reviewed-by: Jonathan Cameron Reviewed-by: Alexandru Ardelean Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20220520075737.758761-4-u.kleine-koenig@pengutronix.de Signed-off-by: Stephen Boyd --- drivers/clk/clk-devres.c | 27 ++++++++++++ include/linux/clk.h | 109 +++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 136 insertions(+) (limited to 'drivers/clk/clk-devres.c') diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c index c822f4ef1584..43ccd20e0298 100644 --- a/drivers/clk/clk-devres.c +++ b/drivers/clk/clk-devres.c @@ -66,12 +66,39 @@ struct clk *devm_clk_get(struct device *dev, const char *id) } EXPORT_SYMBOL(devm_clk_get); +struct clk *devm_clk_get_prepared(struct device *dev, const char *id) +{ + return __devm_clk_get(dev, id, clk_get, clk_prepare, clk_unprepare); +} +EXPORT_SYMBOL_GPL(devm_clk_get_prepared); + +struct clk *devm_clk_get_enabled(struct device *dev, const char *id) +{ + return __devm_clk_get(dev, id, clk_get, + clk_prepare_enable, clk_disable_unprepare); +} +EXPORT_SYMBOL_GPL(devm_clk_get_enabled); + struct clk *devm_clk_get_optional(struct device *dev, const char *id) { return __devm_clk_get(dev, id, clk_get_optional, NULL, NULL); } EXPORT_SYMBOL(devm_clk_get_optional); +struct clk *devm_clk_get_optional_prepared(struct device *dev, const char *id) +{ + return __devm_clk_get(dev, id, clk_get_optional, + clk_prepare, clk_unprepare); +} +EXPORT_SYMBOL_GPL(devm_clk_get_optional_prepared); + +struct clk *devm_clk_get_optional_enabled(struct device *dev, const char *id) +{ + return __devm_clk_get(dev, id, clk_get_optional, + clk_prepare_enable, clk_disable_unprepare); +} +EXPORT_SYMBOL_GPL(devm_clk_get_optional_enabled); + struct clk_bulk_devres { struct clk_bulk_data *clks; int num_clks; diff --git a/include/linux/clk.h b/include/linux/clk.h index c8fc398d2ad7..c13061cabdfc 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -459,6 +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. @@ -482,6 +523,50 @@ struct clk *devm_clk_get(struct device *dev, const char *id); */ struct clk *devm_clk_get_optional(struct device *dev, const char *id); +/** + * devm_clk_get_optional_prepared - devm_clk_get_optional() + 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. 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_clk_get_optional_prepared(struct device *dev, const char *id); + +/** + * devm_clk_get_optional_enabled - devm_clk_get_optional() + + * 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. 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(). + * + * 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_optional_enabled(struct device *dev, const char *id); + /** * devm_get_clk_from_child - lookup and obtain a managed reference to a * clock producer from child node. @@ -826,12 +911,36 @@ 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) { -- cgit v1.2.3 From 8b3d743fc9e2542822826890b482afabf0e7522a Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Mon, 20 Jun 2022 19:18:15 +0200 Subject: clk: Fix pointer casting to prevent oops in devm_clk_release() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The release function is called with a pointer to the memory returned by devres_alloc(). I was confused about that by the code before the generalization that used a struct clk **ptr. Reported-by: Marek Szyprowski Fixes: abae8e57e49a ("clk: generalize devm_clk_get() a bit") Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20220620171815.114212-1-u.kleine-koenig@pengutronix.de Tested-by: Marek Szyprowski Tested-by: Linux Kernel Functional Testing Signed-off-by: Stephen Boyd --- drivers/clk/clk-devres.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/clk/clk-devres.c') diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c index 43ccd20e0298..4fb4fd4b06bd 100644 --- a/drivers/clk/clk-devres.c +++ b/drivers/clk/clk-devres.c @@ -11,7 +11,7 @@ struct devm_clk_state { static void devm_clk_release(struct device *dev, void *res) { - struct devm_clk_state *state = *(struct devm_clk_state **)res; + struct devm_clk_state *state = res; if (state->exit) state->exit(state->clk); -- cgit v1.2.3