clk: Use a separate struct for holding init data.

Create a struct clk_init_data to hold all data that needs to be passed from
the platfrom specific driver to the common clock framework during clock
registration. Add a pointer to this struct inside clk_hw.

This has several advantages:
* Completely hides struct clk from many clock platform drivers and static
  clock initialization code that don't care for static initialization of
  the struct clks.
* For platforms that want to do complete static initialization, it removed
  the need to directly mess with the struct clk's fields while still
  allowing to statically allocate struct clk. This keeps the code more
  future proof even if they include clk-private.h.
* Simplifies the generic clk_register() function and allows adding optional
  fields in the future without modifying the function signature.
* Simplifies the static initialization of clocks on all platforms by
  removing the need for forward delcarations or convoluted macros.

Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
[mturquette@linaro.org: kept DEFINE_CLK_* macros and __clk_init]
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jeremy Kerr <jeremy.kerr@canonical.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergman <arnd.bergmann@linaro.org>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Shawn Guo <shawn.guo@freescale.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Jamie Iles <jamie@jamieiles.com>
Cc: Richard Zhao <richard.zhao@linaro.org>
Cc: Saravana Kannan <skannan@codeaurora.org>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Amit Kucheria <amit.kucheria@linaro.org>
Cc: Deepak Saxena <dsaxena@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 38 insertions, 21 deletions

diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index 8f21489..5db3412 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -15,19 +15,6 @@
 
 #ifdef CONFIG_COMMON_CLK
 
-/**
- * struct clk_hw - handle for traversing from a struct clk to its corresponding
- * hardware-specific structure.  struct clk_hw should be declared within struct
- * clk_foo and then referenced by the struct clk instance that uses struct
- * clk_foo's clk_ops
- *
- * clk: pointer to the struct clk instance that points back to this struct
- * clk_hw instance
- */
-struct clk_hw {
-	struct clk *clk;
-};
-
 /*
  * flags used across common struct clk.  these flags should only affect the
  * top-level framework.  custom flags for dealing with hardware specifics
@@ -39,6 +26,8 @@ struct clk_hw {
 #define CLK_IGNORE_UNUSED	BIT(3) /* do not gate even if unused */
 #define CLK_IS_ROOT		BIT(4) /* root clk, has no parent */
 
+struct clk_hw;
+
 /**
  * struct clk_ops -  Callback operations for hardware clocks; these are to
  * be provided by the clock implementation, and will be called by drivers
@@ -122,6 +111,41 @@ struct clk_ops {
 	void		(*init)(struct clk_hw *hw);
 };
 
+/**
+ * struct clk_init_data - holds init data that's common to all clocks and is
+ * shared between the clock provider and the common clock framework.
+ *
+ * @name: clock name
+ * @ops: operations this clock supports
+ * @parent_names: array of string names for all possible parents
+ * @num_parents: number of possible parents
+ * @flags: framework-level hints and quirks
+ */
+struct clk_init_data {
+	const char		*name;
+	const struct clk_ops	*ops;
+	const char		**parent_names;
+	u8			num_parents;
+	unsigned long		flags;
+};
+
+/**
+ * struct clk_hw - handle for traversing from a struct clk to its corresponding
+ * hardware-specific structure.  struct clk_hw should be declared within struct
+ * clk_foo and then referenced by the struct clk instance that uses struct
+ * clk_foo's clk_ops
+ *
+ * @clk: pointer to the struct clk instance that points back to this struct
+ * clk_hw instance
+ *
+ * @init: pointer to struct clk_init_data that contains the init data shared
+ * with the common clock framework.
+ */
+struct clk_hw {
+	struct clk *clk;
+	struct clk_init_data *init;
+};
+
 /*
  * DOC: Basic clock implementations common to many platforms
  *
@@ -255,12 +279,7 @@ struct clk *clk_register_mux(struct device *dev, const char *name,
 /**
  * clk_register - allocate a new clock, register it and return an opaque cookie
  * @dev: device that is registering this clock
- * @name: clock name
- * @ops: operations this clock supports
  * @hw: link to hardware-specific clock data
- * @parent_names: array of string names for all possible parents
- * @num_parents: number of possible parents
- * @flags: framework-level hints and quirks
  *
  * clk_register is the primary interface for populating the clock tree with new
  * clock nodes.  It returns a pointer to the newly allocated struct clk which
@@ -268,9 +287,7 @@ struct clk *clk_register_mux(struct device *dev, const char *name,
  * rest of the clock API.  In the event of an error clk_register will return an
  * error code; drivers must test for an error code after calling clk_register.
  */
-struct clk *clk_register(struct device *dev, const char *name,
-		const struct clk_ops *ops, struct clk_hw *hw,
-		const char **parent_names, u8 num_parents, unsigned long flags);
+struct clk *clk_register(struct device *dev, struct clk_hw *hw);
 
 /* helper functions */
 const char *__clk_get_name(struct clk *clk);