From ac2df527fb407b61f9c812a99035b62a75a77d6d Mon Sep 17 00:00:00 2001 From: Sylwester Nawrocki Date: Sat, 24 Aug 2013 20:10:41 +0200 Subject: clk: Add common __clk_get(), __clk_put() implementations This patch adds common __clk_get(), __clk_put() clkdev helpers that replace their platform specific counterparts when the common clock API is used. The owner module pointer field is added to struct clk so a reference to the clock supplier module can be taken by the clock consumers. The owner module is assigned while the clock is being registered, in functions _clk_register() and __clk_register(). Signed-off-by: Sylwester Nawrocki Signed-off-by: Kyungmin Park Acked-by: Russell King --- include/linux/clk-private.h | 3 +++ include/linux/clkdev.h | 5 +++++ 2 files changed, 8 insertions(+) (limited to 'include/linux') diff --git a/include/linux/clk-private.h b/include/linux/clk-private.h index 8138c94409f3..8cb1865e7d9d 100644 --- a/include/linux/clk-private.h +++ b/include/linux/clk-private.h @@ -25,10 +25,13 @@ #ifdef CONFIG_COMMON_CLK +struct module; + struct clk { const char *name; const struct clk_ops *ops; struct clk_hw *hw; + struct module *owner; struct clk *parent; const char **parent_names; struct clk **parents; diff --git a/include/linux/clkdev.h b/include/linux/clkdev.h index a6a6f603103b..94bad77eeb4a 100644 --- a/include/linux/clkdev.h +++ b/include/linux/clkdev.h @@ -43,4 +43,9 @@ 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); +#ifdef CONFIG_COMMON_CLK +int __clk_get(struct clk *clk); +void __clk_put(struct clk *clk); +#endif + #endif -- cgit v1.2.3 From fcb0ee6a3d331fb23dbb546500021f6e4cac5689 Mon Sep 17 00:00:00 2001 From: Sylwester Nawrocki Date: Sat, 24 Aug 2013 15:00:10 +0200 Subject: clk: Implement clk_unregister clk_unregister() is currently not implemented and it is required when a clock provider module needs to be unloaded. Normally the clock supplier module is prevented to be unloaded by taking reference on the module in clk_get(). For cases when the clock supplier module deinitializes despite the consumers of its clocks holding a reference on the module, e.g. when the driver is unbound through "unbind" sysfs attribute, there are empty clock ops added. These ops are assigned temporarily to struct clk and used until all consumers release the clock, to avoid invoking callbacks from the module which just got removed. Signed-off-by: Jiada Wang Signed-off-by: Sylwester Nawrocki Signed-off-by: Kyungmin Park --- include/linux/clk-private.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux') diff --git a/include/linux/clk-private.h b/include/linux/clk-private.h index 8cb1865e7d9d..72c65e05450b 100644 --- a/include/linux/clk-private.h +++ b/include/linux/clk-private.h @@ -12,6 +12,7 @@ #define __LINUX_CLK_PRIVATE_H #include +#include #include /* @@ -50,6 +51,7 @@ struct clk { #ifdef CONFIG_COMMON_CLK_DEBUG struct dentry *dentry; #endif + struct kref ref; }; /* -- cgit v1.2.3 From 5279fc402ae59361a224d641d5823b21b4206232 Mon Sep 17 00:00:00 2001 From: Boris BREZILLON Date: Sat, 21 Dec 2013 10:34:47 +0100 Subject: clk: add clk accuracy retrieval support The clock accuracy is expressed in ppb (parts per billion) and represents the possible clock drift. Say you have a clock (e.g. an oscillator) which provides a fixed clock of 20MHz with an accuracy of +- 20Hz. This accuracy expressed in ppb is 20Hz/20MHz = 1000 ppb (or 1 ppm). Clock users may need the clock accuracy information in order to choose the best clock (the one with the best accuracy) across several available clocks. This patch adds clk accuracy retrieval support for common clk framework by means of a new function called clk_get_accuracy. This function returns the given clock accuracy expressed in ppb. In order to get the clock accuracy, this implementation adds one callback called recalc_accuracy to the clk_ops structure. This callback is given the parent clock accuracy (if the clock is not a root clock) and should recalculate the given clock accuracy. This callback is optional and may be implemented if the clock is not a perfect clock (accuracy != 0 ppb). Signed-off-by: Boris BREZILLON Signed-off-by: Mike Turquette --- include/linux/clk-private.h | 1 + include/linux/clk-provider.h | 11 +++++++++++ include/linux/clk.h | 17 +++++++++++++++++ 3 files changed, 29 insertions(+) (limited to 'include/linux') diff --git a/include/linux/clk-private.h b/include/linux/clk-private.h index 8138c94409f3..accb517e77e9 100644 --- a/include/linux/clk-private.h +++ b/include/linux/clk-private.h @@ -41,6 +41,7 @@ struct clk { unsigned long flags; unsigned int enable_count; unsigned int prepare_count; + unsigned long accuracy; struct hlist_head children; struct hlist_node child_node; unsigned int notifier_count; diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index 7e59253b8603..16d182c28ce6 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -29,6 +29,7 @@ #define CLK_IS_BASIC BIT(5) /* Basic clk, can't do a to_clk_foo() */ #define CLK_GET_RATE_NOCACHE BIT(6) /* do not use the cached clk rate */ #define CLK_SET_RATE_NO_REPARENT BIT(7) /* don't re-parent on rate change */ +#define CLK_GET_ACCURACY_NOCACHE BIT(8) /* do not use the cached clk accuracy */ struct clk_hw; @@ -108,6 +109,13 @@ struct clk_hw; * which is likely helpful for most .set_rate implementation. * Returns 0 on success, -EERROR otherwise. * + * @recalc_accuracy: Recalculate the accuracy of this clock. The clock accuracy + * is expressed in ppb (parts per billion). The parent accuracy is + * an input parameter. + * Returns the calculated accuracy. Optional - if this op is not + * set then clock accuracy will be initialized to parent accuracy + * or 0 (perfect clock) if clock has no parent. + * * The clk_enable/clk_disable and clk_prepare/clk_unprepare pairs allow * implementations to split any work between atomic (enable) and sleepable * (prepare) contexts. If enabling a clock requires code that might sleep, @@ -139,6 +147,8 @@ struct clk_ops { u8 (*get_parent)(struct clk_hw *hw); int (*set_rate)(struct clk_hw *hw, unsigned long, unsigned long); + unsigned long (*recalc_accuracy)(struct clk_hw *hw, + unsigned long parent_accuracy); void (*init)(struct clk_hw *hw); }; @@ -433,6 +443,7 @@ struct clk *clk_get_parent_by_index(struct clk *clk, u8 index); unsigned int __clk_get_enable_count(struct clk *clk); unsigned int __clk_get_prepare_count(struct clk *clk); unsigned long __clk_get_rate(struct clk *clk); +unsigned long __clk_get_accuracy(struct clk *clk); unsigned long __clk_get_flags(struct clk *clk); bool __clk_is_prepared(struct clk *clk); bool __clk_is_enabled(struct clk *clk); diff --git a/include/linux/clk.h b/include/linux/clk.h index 9a6d04524b1a..0dd91148165e 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -82,6 +82,23 @@ int clk_notifier_register(struct clk *clk, struct notifier_block *nb); int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb); +/** + * clk_get_accuracy - obtain the clock accuracy in ppb (parts per billion) + * for a clock source. + * @clk: clock source + * + * This gets the clock source accuracy expressed in ppb. + * A perfect clock returns 0. + */ +long clk_get_accuracy(struct clk *clk); + +#else + +static inline long clk_get_accuracy(struct clk *clk) +{ + return -ENOTSUPP; +} + #endif /** -- cgit v1.2.3 From 0903ea60173fab226a867ceb080b2e0269a6c975 Mon Sep 17 00:00:00 2001 From: Boris BREZILLON Date: Sat, 21 Dec 2013 10:34:48 +0100 Subject: clk: add accuracy support for fixed clock This patch adds support for accuracy retrieval on fixed clocks. It also adds a new dt property called 'clock-accuracy' to define the clock accuracy. This can be usefull for oscillator (RC, crystal, ...) definitions which are always given an accuracy characteristic. Signed-off-by: Boris BREZILLON Signed-off-by: Mike Turquette --- include/linux/clk-provider.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/linux') diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index 16d182c28ce6..5429f5db5037 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -204,6 +204,7 @@ struct clk_hw { struct clk_fixed_rate { struct clk_hw hw; unsigned long fixed_rate; + unsigned long fixed_accuracy; u8 flags; }; @@ -211,6 +212,9 @@ extern const struct clk_ops clk_fixed_rate_ops; struct clk *clk_register_fixed_rate(struct device *dev, const char *name, const char *parent_name, unsigned long flags, unsigned long fixed_rate); +struct clk *clk_register_fixed_rate_with_accuracy(struct device *dev, + const char *name, const char *parent_name, unsigned long flags, + unsigned long fixed_rate, unsigned long fixed_accuracy); void of_fixed_clk_setup(struct device_node *np); -- cgit v1.2.3 From ea72dc2cf9552631e43327ce593bdbb0b9fdf058 Mon Sep 17 00:00:00 2001 From: Mike Turquette Date: Wed, 18 Dec 2013 21:38:52 -0800 Subject: clk: remove CONFIG_COMMON_CLK_DEBUG Populate ${DEBUGS_MOUNT_POINT}/clk if CONFIG_DEBUG_FS is set. This eliminates the extra (annoying) step of enabling the config option manually. Signed-off-by: Mike Turquette --- include/linux/clk-private.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/clk-private.h b/include/linux/clk-private.h index accb517e77e9..5fb086b06c83 100644 --- a/include/linux/clk-private.h +++ b/include/linux/clk-private.h @@ -45,7 +45,7 @@ struct clk { struct hlist_head children; struct hlist_node child_node; unsigned int notifier_count; -#ifdef CONFIG_COMMON_CLK_DEBUG +#ifdef CONFIG_DEBUG_FS struct dentry *dentry; #endif }; -- cgit v1.2.3 From d0d44dd4ac58bc547646a9d0e65b4648f97cb533 Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Wed, 15 Jan 2014 10:47:21 -0800 Subject: reset: Silence warning in reset-controller.h If a user of doesn't include before including reset-controller.h they'll get a warning as follows: include/linux/reset-controller.h:44:17: warning: 'struct of_phandle_args' declared inside parameter list This is because of_phandle_args is not forward declared. Add the declaration to silence this warning. Acked-by: Philipp Zabel Signed-off-by: Stephen Boyd Signed-off-by: Mike Turquette --- include/linux/reset-controller.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux') diff --git a/include/linux/reset-controller.h b/include/linux/reset-controller.h index 2f61311ae3e0..41a4695fde08 100644 --- a/include/linux/reset-controller.h +++ b/include/linux/reset-controller.h @@ -21,6 +21,7 @@ struct reset_control_ops { struct module; struct device_node; +struct of_phandle_args; /** * struct reset_controller_dev - reset controller entity that might -- cgit v1.2.3 From 3fa2252b7a78a8057017471a28f47b306e95ee26 Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Wed, 15 Jan 2014 10:47:22 -0800 Subject: clk: Add set_rate_and_parent() op Some of Qualcomm's clocks can change their parent and rate at the same time with a single register write. Add support for this hardware to the common clock framework by adding a new set_rate_and_parent() op. When the clock framework determines that both the parent and the rate are going to change during clk_set_rate() it will call the .set_rate_and_parent() op if available and fall back to calling .set_parent() followed by .set_rate() otherwise. Reviewed-by: James Hogan Signed-off-by: Stephen Boyd Signed-off-by: Mike Turquette --- include/linux/clk-provider.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'include/linux') diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index 5429f5db5037..999b28ba38f7 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -116,6 +116,18 @@ struct clk_hw; * set then clock accuracy will be initialized to parent accuracy * or 0 (perfect clock) if clock has no parent. * + * @set_rate_and_parent: Change the rate and the parent of this clock. The + * requested rate is specified by the second argument, which + * should typically be the return of .round_rate call. The + * third argument gives the parent rate which is likely helpful + * for most .set_rate_and_parent implementation. The fourth + * argument gives the parent index. This callback is optional (and + * unnecessary) for clocks with 0 or 1 parents as well as + * for clocks that can tolerate switching the rate and the parent + * separately via calls to .set_parent and .set_rate. + * Returns 0 on success, -EERROR otherwise. + * + * * The clk_enable/clk_disable and clk_prepare/clk_unprepare pairs allow * implementations to split any work between atomic (enable) and sleepable * (prepare) contexts. If enabling a clock requires code that might sleep, @@ -147,6 +159,9 @@ struct clk_ops { u8 (*get_parent)(struct clk_hw *hw); int (*set_rate)(struct clk_hw *hw, unsigned long, unsigned long); + int (*set_rate_and_parent)(struct clk_hw *hw, + unsigned long rate, + unsigned long parent_rate, u8 index); unsigned long (*recalc_accuracy)(struct clk_hw *hw, unsigned long parent_accuracy); void (*init)(struct clk_hw *hw); -- cgit v1.2.3