From 766e6a4ec602d0c107553b91b3434fe9c03474f4 Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Mon, 9 Apr 2012 14:50:06 -0500 Subject: clk: add DT clock binding support Based on work 1st by Ben Herrenschmidt and Jeremy Kerr, then by Grant Likely, this patch adds support to clk_get to allow drivers to retrieve clock data from the device tree. Platforms scan for clocks in DT with of_clk_init and a match table, and the register a provider through of_clk_add_provider. The provider's clk_src_get function will be called when a device references the provider's OF node for a clock reference. v6 (Rob Herring): - Return error values instead of NULL to match clock framework expectations v5 (Rob Herring): - Move from drivers/of into common clock subsystem - Squashed "dt/clock: add a simple provider get function" and "dt/clock: add function to get parent clock name" - Rebase to 3.4-rc1 - Drop CONFIG_OF_CLOCK and just use CONFIG_OF - Add missing EXPORT_SYMBOL to various functions - s/clock-output-name/clock-output-names/ - Define that fixed-clock binding is a single output v4 (Rob Herring): - Rework for common clk subsystem - Add of_clk_get_parent_name function v3: - Clarified documentation v2: - fixed errant ';' causing compile error - Editorial fixes from Shawn Guo - merged in adding lookup to clkdev - changed property names to match established convention. After working with the binding a bit it really made more sense to follow the lead of 'reg', 'gpios' and 'interrupts' by making the input simply 'clocks' & 'clock-names' instead of 'clock-input-*', and to only use clock-output* for the producer nodes. (Sorry Shawn, this will mean you need to change some code, but it should be trivial) - Add ability to inherit clocks from parent nodes by using an empty 'clock-ranges' property. Useful for busses. I could use some feedback on the new property name, 'clock-ranges' doesn't feel right to me. Signed-off-by: Grant Likely Signed-off-by: Rob Herring Reviewed-by: Shawn Guo Cc: Sascha Hauer Signed-off-by: Mike Turquette --- include/linux/clk-provider.h | 14 ++++++++++++++ include/linux/clk.h | 19 +++++++++++++++++++ 2 files changed, 33 insertions(+) (limited to 'include/linux') diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index 06ad617664a2..7c9c691102b5 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -347,5 +347,19 @@ void __clk_unprepare(struct clk *clk); void __clk_reparent(struct clk *clk, struct clk *new_parent); unsigned long __clk_round_rate(struct clk *clk, unsigned long rate); +struct of_device_id; + +typedef void (*of_clk_init_cb_t)(struct device_node *); + +int of_clk_add_provider(struct device_node *np, + struct clk *(*clk_src_get)(struct of_phandle_args *args, + void *data), + void *data); +void of_clk_del_provider(struct device_node *np); +struct clk *of_clk_src_simple_get(struct of_phandle_args *clkspec, + void *data); +const char *of_clk_get_parent_name(struct device_node *np, int index); +void of_clk_init(const struct of_device_id *matches); + #endif /* CONFIG_COMMON_CLK */ #endif /* CLK_PROVIDER_H */ diff --git a/include/linux/clk.h b/include/linux/clk.h index ad5c43e8ae8a..8b70342e7e0b 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -310,4 +310,23 @@ struct clk *clk_get_sys(const char *dev_id, const char *con_id); int clk_add_alias(const char *alias, const char *alias_dev_name, char *id, struct device *dev); +struct device_node; +struct of_phandle_args; + +#ifdef CONFIG_OF +struct clk *of_clk_get(struct device_node *np, int index); +struct clk *of_clk_get_by_name(struct device_node *np, const char *name); +struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec); +#else +static inline struct clk *of_clk_get(struct device_node *np, int index) +{ + return NULL; +} +static inline struct clk *of_clk_get_by_name(struct device_node *np, + const char *name) +{ + return NULL; +} +#endif + #endif -- cgit v1.2.3-59-g8ed1b