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-rw-r--r--include/linux/clk-provider.h120
1 files changed, 79 insertions, 41 deletions
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index 5508897ad376..4a0b483986c3 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
@@ -88,19 +77,11 @@ struct clk_hw {
* array index into the value programmed into the hardware.
* Returns 0 on success, -EERROR otherwise.
*
- * @set_rate: Change the rate of this clock. If this callback returns
- * CLK_SET_RATE_PARENT, the rate change will be propagated to the
- * parent clock (which may propagate again if the parent clock
- * also sets this flag). The requested rate of the parent is
- * passed back from the callback in the second 'unsigned long *'
- * argument. Note that it is up to the hardware clock's set_rate
- * implementation to insure that clocks do not run out of spec
- * when propgating the call to set_rate up to the parent. One way
- * to do this is to gate the clock (via clk_disable and/or
- * clk_unprepare) before calling clk_set_rate, then ungating it
- * afterward. If your clock also has the CLK_GATE_SET_RATE flag
- * set then this will insure safety. Returns 0 on success,
- * -EERROR otherwise.
+ * @set_rate: Change the rate 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 implementation.
+ * 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
@@ -125,10 +106,46 @@ struct clk_ops {
unsigned long *);
int (*set_parent)(struct clk_hw *hw, u8 index);
u8 (*get_parent)(struct clk_hw *hw);
- int (*set_rate)(struct clk_hw *hw, unsigned long);
+ int (*set_rate)(struct clk_hw *hw, unsigned long,
+ unsigned long);
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
*
@@ -149,6 +166,7 @@ struct clk_fixed_rate {
u8 flags;
};
+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);
@@ -165,7 +183,7 @@ struct clk *clk_register_fixed_rate(struct device *dev, const char *name,
* Clock which can gate its output. Implements .enable & .disable
*
* Flags:
- * CLK_GATE_SET_DISABLE - by default this clock sets the bit at bit_idx to
+ * CLK_GATE_SET_TO_DISABLE - by default this clock sets the bit at bit_idx to
* enable the clock. Setting this flag does the opposite: setting the bit
* disable the clock and clearing it enables the clock
*/
@@ -175,11 +193,11 @@ struct clk_gate {
u8 bit_idx;
u8 flags;
spinlock_t *lock;
- char *parent[1];
};
#define CLK_GATE_SET_TO_DISABLE BIT(0)
+extern const struct clk_ops clk_gate_ops;
struct clk *clk_register_gate(struct device *dev, const char *name,
const char *parent_name, unsigned long flags,
void __iomem *reg, u8 bit_idx,
@@ -212,12 +230,12 @@ struct clk_divider {
u8 width;
u8 flags;
spinlock_t *lock;
- char *parent[1];
};
#define CLK_DIVIDER_ONE_BASED BIT(0)
#define CLK_DIVIDER_POWER_OF_TWO BIT(1)
+extern const struct clk_ops clk_divider_ops;
struct clk *clk_register_divider(struct device *dev, const char *name,
const char *parent_name, unsigned long flags,
void __iomem *reg, u8 shift, u8 width,
@@ -238,7 +256,7 @@ struct clk *clk_register_divider(struct device *dev, const char *name,
*
* Flags:
* CLK_MUX_INDEX_ONE - register index starts at 1, not 0
- * CLK_MUX_INDEX_BITWISE - register index is a single bit (power of two)
+ * CLK_MUX_INDEX_BIT - register index is a single bit (power of two)
*/
struct clk_mux {
struct clk_hw hw;
@@ -252,29 +270,49 @@ struct clk_mux {
#define CLK_MUX_INDEX_ONE BIT(0)
#define CLK_MUX_INDEX_BIT BIT(1)
+extern const struct clk_ops clk_mux_ops;
struct clk *clk_register_mux(struct device *dev, const char *name,
- char **parent_names, u8 num_parents, unsigned long flags,
+ const char **parent_names, u8 num_parents, unsigned long flags,
void __iomem *reg, u8 shift, u8 width,
u8 clk_mux_flags, spinlock_t *lock);
/**
+ * struct clk_fixed_factor - fixed multiplier and divider clock
+ *
+ * @hw: handle between common and hardware-specific interfaces
+ * @mult: multiplier
+ * @div: divider
+ *
+ * Clock with a fixed multiplier and divider. The output frequency is the
+ * parent clock rate divided by div and multiplied by mult.
+ * Implements .recalc_rate, .set_rate and .round_rate
+ */
+
+struct clk_fixed_factor {
+ struct clk_hw hw;
+ unsigned int mult;
+ unsigned int div;
+};
+
+extern struct clk_ops clk_fixed_factor_ops;
+struct clk *clk_register_fixed_factor(struct device *dev, const char *name,
+ const char *parent_name, unsigned long flags,
+ unsigned int mult, unsigned int div);
+
+/**
* 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
* cannot be dereferenced by driver code but may be used in conjuction with the
- * rest of the clock API.
+ * 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,
- char **parent_names, u8 num_parents, unsigned long flags);
+struct clk *clk_register(struct device *dev, struct clk_hw *hw);
+
+void clk_unregister(struct clk *clk);
/* helper functions */
const char *__clk_get_name(struct clk *clk);