From 1df4046a93e086f77d244ea47c21591b4acad3e2 Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Tue, 11 Dec 2018 08:32:04 -0800 Subject: clk: Combine __clk_get() and __clk_create_clk() The __clk_get() function is practically a private clk implementation detail now. No architecture defines it, and given that new code should be using the common clk framework there isn't a need for it to keep existing just to serve clkdev purposes. Let's fold it into the __clk_create_clk() function and make that a little more generic by renaming it to clk_hw_create_clk(). This will allow the framework to create a struct clk handle to a particular clk_hw pointer and link it up as a consumer wherever that's needed. Doing this also lets us get rid of the __clk_free_clk() API that had to be kept in sync with __clk_put(). Splitting that API up into the "link and unlink from consumer list" phase and "free the clk pointer" phase allows us to reuse that logic in a couple places, simplifying the code. Cc: Miquel Raynal Cc: Jerome Brunet Cc: Russell King Cc: Michael Turquette Cc: Jeffrey Hugo Cc: Chen-Yu Tsai Signed-off-by: Stephen Boyd --- drivers/clk/clk.c | 140 ++++++++++++++++++++++++++++++++++----------------- drivers/clk/clk.h | 10 ++-- drivers/clk/clkdev.c | 9 +--- 3 files changed, 98 insertions(+), 61 deletions(-) (limited to 'drivers/clk') diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index d2477a5058ac..fef937ea44f4 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -3209,42 +3209,103 @@ unlock: return ret; } -struct clk *__clk_create_clk(struct clk_hw *hw, const char *dev_id, +/** + * clk_core_link_consumer - Add a clk consumer to the list of consumers in a clk_core + * @core: clk to add consumer to + * @clk: consumer to link to a clk + */ +static void clk_core_link_consumer(struct clk_core *core, struct clk *clk) +{ + clk_prepare_lock(); + hlist_add_head(&clk->clks_node, &core->clks); + clk_prepare_unlock(); +} + +/** + * clk_core_unlink_consumer - Remove a clk consumer from the list of consumers in a clk_core + * @clk: consumer to unlink + */ +static void clk_core_unlink_consumer(struct clk *clk) +{ + lockdep_assert_held(&prepare_lock); + hlist_del(&clk->clks_node); +} + +/** + * alloc_clk - Allocate a clk consumer, but leave it unlinked to the clk_core + * @core: clk to allocate a consumer for + * @dev_id: string describing device name + * @con_id: connection ID string on device + * + * Returns: clk consumer left unlinked from the consumer list + */ +static struct clk *alloc_clk(struct clk_core *core, const char *dev_id, const char *con_id) { struct clk *clk; - /* This is to allow this function to be chained to others */ - if (IS_ERR_OR_NULL(hw)) - return ERR_CAST(hw); - clk = kzalloc(sizeof(*clk), GFP_KERNEL); if (!clk) return ERR_PTR(-ENOMEM); - clk->core = hw->core; + clk->core = core; clk->dev_id = dev_id; clk->con_id = kstrdup_const(con_id, GFP_KERNEL); clk->max_rate = ULONG_MAX; - clk_prepare_lock(); - hlist_add_head(&clk->clks_node, &hw->core->clks); - clk_prepare_unlock(); - return clk; } -/* keep in sync with __clk_put */ -void __clk_free_clk(struct clk *clk) +/** + * free_clk - Free a clk consumer + * @clk: clk consumer to free + * + * Note, this assumes the clk has been unlinked from the clk_core consumer + * list. + */ +static void free_clk(struct clk *clk) { - clk_prepare_lock(); - hlist_del(&clk->clks_node); - clk_prepare_unlock(); - kfree_const(clk->con_id); kfree(clk); } +/** + * clk_hw_create_clk: Allocate and link a clk consumer to a clk_core given + * a clk_hw + * @hw: clk_hw associated with the clk being consumed + * @dev_id: string describing device name + * @con_id: connection ID string on device + * + * This is the main function used to create a clk pointer for use by clk + * consumers. It connects a consumer to the clk_core and clk_hw structures + * used by the framework and clk provider respectively. + */ +struct clk *clk_hw_create_clk(struct clk_hw *hw, + const char *dev_id, const char *con_id) +{ + struct clk *clk; + struct clk_core *core; + + /* This is to allow this function to be chained to others */ + if (IS_ERR_OR_NULL(hw)) + return ERR_CAST(hw); + + core = hw->core; + clk = alloc_clk(core, dev_id, con_id); + if (IS_ERR(clk)) + return clk; + + if (!try_module_get(core->owner)) { + free_clk(clk); + return ERR_PTR(-ENOENT); + } + + kref_get(&core->ref); + clk_core_link_consumer(core, clk); + + return clk; +} + /** * clk_register - allocate a new clock, register it and return an opaque cookie * @dev: device that is registering this clock @@ -3320,17 +3381,27 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw) INIT_HLIST_HEAD(&core->clks); - hw->clk = __clk_create_clk(hw, NULL, NULL); + /* + * Don't call clk_hw_create_clk() here because that would pin the + * provider module to itself and prevent it from ever being removed. + */ + hw->clk = alloc_clk(core, NULL, NULL); if (IS_ERR(hw->clk)) { ret = PTR_ERR(hw->clk); goto fail_parents; } + clk_core_link_consumer(hw->core, hw->clk); + ret = __clk_core_init(core); if (!ret) return hw->clk; - __clk_free_clk(hw->clk); + clk_prepare_lock(); + clk_core_unlink_consumer(hw->clk); + clk_prepare_unlock(); + + free_clk(hw->clk); hw->clk = NULL; fail_parents: @@ -3601,20 +3672,7 @@ EXPORT_SYMBOL_GPL(devm_clk_hw_unregister); /* * clkdev helpers */ -int __clk_get(struct clk *clk) -{ - struct clk_core *core = !clk ? NULL : clk->core; - - if (core) { - if (!try_module_get(core->owner)) - return 0; - - kref_get(&core->ref); - } - return 1; -} -/* keep in sync with __clk_free_clk */ void __clk_put(struct clk *clk) { struct module *owner; @@ -3648,8 +3706,7 @@ void __clk_put(struct clk *clk) module_put(owner); - kfree_const(clk->con_id); - kfree(clk); + free_clk(clk); } /*** clk rate change notifiers ***/ @@ -4025,8 +4082,7 @@ struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec, const char *dev_id, const char *con_id) { struct of_clk_provider *provider; - struct clk *clk = ERR_PTR(-EPROBE_DEFER); - struct clk_hw *hw; + struct clk_hw *hw = ERR_PTR(-EPROBE_DEFER); if (!clkspec) return ERR_PTR(-EINVAL); @@ -4036,21 +4092,13 @@ struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec, list_for_each_entry(provider, &of_clk_providers, link) { if (provider->node == clkspec->np) { hw = __of_clk_get_hw_from_provider(provider, clkspec); - clk = __clk_create_clk(hw, dev_id, con_id); - } - - if (!IS_ERR(clk)) { - if (!__clk_get(clk)) { - __clk_free_clk(clk); - clk = ERR_PTR(-ENOENT); - } - - break; + if (!IS_ERR(hw)) + break; } } mutex_unlock(&of_clk_mutex); - return clk; + return clk_hw_create_clk(hw, dev_id, con_id); } /** diff --git a/drivers/clk/clk.h b/drivers/clk/clk.h index b02f5e604e69..4cdf30b0008c 100644 --- a/drivers/clk/clk.h +++ b/drivers/clk/clk.h @@ -12,24 +12,20 @@ struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec, #endif #ifdef CONFIG_COMMON_CLK -struct clk *__clk_create_clk(struct clk_hw *hw, const char *dev_id, - const char *con_id); -void __clk_free_clk(struct clk *clk); -int __clk_get(struct clk *clk); +struct clk *clk_hw_create_clk(struct clk_hw *hw, + const char *dev_id, const char *con_id); void __clk_put(struct clk *clk); #else /* All these casts to avoid ifdefs in clkdev... */ static inline struct clk * -__clk_create_clk(struct clk_hw *hw, const char *dev_id, const char *con_id) +clk_hw_create_clk(struct clk_hw *hw, const char *dev_id, const char *con_id) { return (struct clk *)hw; } -static inline void __clk_free_clk(struct clk *clk) { } static struct clk_hw *__clk_get_hw(struct clk *clk) { return (struct clk_hw *)clk; } -static inline int __clk_get(struct clk *clk) { return 1; } static inline void __clk_put(struct clk *clk) { } #endif diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c index 9ab3db8b3988..bdeaffc950ae 100644 --- a/drivers/clk/clkdev.c +++ b/drivers/clk/clkdev.c @@ -174,16 +174,9 @@ struct clk *clk_get_sys(const char *dev_id, const char *con_id) if (!cl) goto out; - clk = __clk_create_clk(cl->clk_hw, dev_id, con_id); + clk = clk_hw_create_clk(cl->clk_hw, dev_id, con_id); if (IS_ERR(clk)) - goto out; - - if (!__clk_get(clk)) { - __clk_free_clk(clk); cl = NULL; - goto out; - } - out: mutex_unlock(&clocks_mutex); -- cgit v1.2.3-58-ga151