clk: Add client API to HTML docs

This converts the existing client (aka clk.h) documentation to kernel doc
format, and adds it to the HTML docs. I have tried to preserve existing
comments as much as possible, refraining from semantic changes.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Tested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Link: https://lore.kernel.org/r/20211222171114.3091780-4-seanga2@gmail.com
[rebased onto u-boot/master and resolved conflicts]
Signed-off-by: Sean Anderson <seanga2@gmail.com>

1 files changed, 85 insertions, 91 deletions

diff --git a/include/clk.h b/include/clk.h
index 6706afa55dd..303b04a726e 100644
--- a/include/clk.h
+++ b/include/clk.h
@@ -14,6 +14,8 @@
 #include <linux/types.h>
 
 /**
+ * DOC: Overview
+ *
  * A clock is a hardware signal that oscillates autonomously at a specific
  * frequency and duty cycle. Most hardware modules require one or more clock
  * signal to drive their operation. Clock signals are typically generated
@@ -34,22 +36,22 @@ struct udevice;
 
 /**
  * struct clk - A handle to (allowing control of) a single clock.
- *
- * Clients provide storage for clock handles. The content of the structure is
- * managed solely by the clock API and clock drivers. A clock struct is
- * initialized by "get"ing the clock struct. The clock struct is passed to all
- * other clock APIs to identify which clock signal to operate upon.
- *
  * @dev: The device which implements the clock signal.
  * @rate: The clock rate (in HZ).
- * @flags: Flags used across common clock structure (e.g. CLK_)
+ * @flags: Flags used across common clock structure (e.g. %CLK_)
  *         Clock IP blocks specific flags (i.e. mux, div, gate, etc) are defined
- *         in struct's for those devices (e.g. struct clk_mux).
+ *         in struct's for those devices (e.g. &struct clk_mux).
+ * @enable_count: The number of times this clock has been enabled.
  * @id: The clock signal ID within the provider.
  * @data: An optional data field for scenarios where a single integer ID is not
  *	  sufficient. If used, it can be populated through an .of_xlate op and
  *	  processed during the various clock ops.
  *
+ * Clients provide storage for clock handles. The content of the structure is
+ * managed solely by the clock API and clock drivers. A clock struct is
+ * initialized by "get"ing the clock struct. The clock struct is passed to all
+ * other clock APIs to identify which clock signal to operate upon.
+ *
  * Should additional information to identify and configure any clock signal
  * for any provider be required in the future, the struct could be expanded to
  * either (a) add more fields to allow clock providers to store additional
@@ -72,15 +74,14 @@ struct clk {
 
 /**
  * struct clk_bulk - A handle to (allowing control of) a bulk of clocks.
+ * @clks: An array of clock handles.
+ * @count: The number of clock handles in the clks array.
  *
  * Clients provide storage for the clock bulk. The content of the structure is
  * managed solely by the clock API. A clock bulk struct is
  * initialized by "get"ing the clock bulk struct.
  * The clock bulk struct is passed to all other bulk clock APIs to apply
  * the API to all the clock in the bulk struct.
- *
- * @clks: An array of clock handles.
- * @count: The number of clock handles in the clks array.
  */
 struct clk_bulk {
 	struct clk *clks;
@@ -91,16 +92,19 @@ struct clk_bulk {
 struct phandle_1_arg;
 /**
  * clk_get_by_phandle() - Get a clock by its phandle information (of-platadata)
+ * @dev: Device containing the phandle
+ * @cells: Phandle info
+ * @clk: A pointer to a clock struct to initialise
  *
  * This function is used when of-platdata is enabled.
  *
  * This looks up a clock using the phandle info. With dtoc, each phandle in the
- * 'clocks' property is transformed into an idx representing the device. For
- * example:
+ * 'clocks' property is transformed into an idx representing the device.
+ * For example::
  *
  *	clocks = <&dpll_mpu_ck 23>;
  *
- * might result in:
+ * might result in::
  *
  *	.clocks = {1, {23}},},
  *
@@ -109,9 +113,6 @@ struct phandle_1_arg;
  * this example it would return a clock containing the 'dpll_mpu_ck' device and
  * the clock ID 23.
  *
- * @dev: Device containing the phandle
- * @cells: Phandle info
- * @clock: A pointer to a clock struct to initialise
  * Return: 0 if OK, or a negative error code.
  */
 int clk_get_by_phandle(struct udevice *dev, const struct phandle_1_arg *cells,
@@ -119,6 +120,10 @@ int clk_get_by_phandle(struct udevice *dev, const struct phandle_1_arg *cells,
 
 /**
  * clk_get_by_index() - Get/request a clock by integer index.
+ * @dev:	The client device.
+ * @index:	The index of the clock to request, within the client's list of
+ *		clocks.
+ * @clk:	A pointer to a clock struct to initialize.
  *
  * This looks up and requests a clock. The index is relative to the client
  * device; each device is assumed to have n clocks associated with it somehow,
@@ -126,30 +131,26 @@ int clk_get_by_phandle(struct udevice *dev, const struct phandle_1_arg *cells,
  * device clock indices to provider clocks may be via device-tree properties,
  * board-provided mapping tables, or some other mechanism.
  *
- * @dev:	The client device.
- * @index:	The index of the clock to request, within the client's list of
- *		clocks.
- * @clock	A pointer to a clock struct to initialize.
  * Return: 0 if OK, or a negative error code.
  */
 int clk_get_by_index(struct udevice *dev, int index, struct clk *clk);
 
 /**
- * clk_get_by_index_nodev - Get/request a clock by integer index
- * without a device.
- *
- * This is a version of clk_get_by_index() that does not use a device.
- *
+ * clk_get_by_index_nodev() - Get/request a clock by integer index without a
+ *                            device.
  * @node:	The client ofnode.
  * @index:	The index of the clock to request, within the client's list of
  *		clocks.
- * @clock	A pointer to a clock struct to initialize.
+ * @clk:	A pointer to a clock struct to initialize.
+ *
  * Return: 0 if OK, or a negative error code.
  */
 int clk_get_by_index_nodev(ofnode node, int index, struct clk *clk);
 
 /**
- * clk_get_bulk - Get/request all clocks of a device.
+ * clk_get_bulk() - Get/request all clocks of a device.
+ * @dev:	The client device.
+ * @bulk:	A pointer to a clock bulk struct to initialize.
  *
  * This looks up and requests all clocks of the client device; each device is
  * assumed to have n clocks associated with it somehow, and this function finds
@@ -157,14 +158,16 @@ int clk_get_by_index_nodev(ofnode node, int index, struct clk *clk);
  * device clock indices to provider clocks may be via device-tree properties,
  * board-provided mapping tables, or some other mechanism.
  *
- * @dev:	The client device.
- * @bulk	A pointer to a clock bulk struct to initialize.
  * Return: 0 if OK, or a negative error code.
  */
 int clk_get_bulk(struct udevice *dev, struct clk_bulk *bulk);
 
 /**
- * clk_get_by_name - Get/request a clock by name.
+ * clk_get_by_name() - Get/request a clock by name.
+ * @dev:	The client device.
+ * @name:	The name of the clock to request, within the client's list of
+ *		clocks.
+ * @clk:	A pointer to a clock struct to initialize.
  *
  * This looks up and requests a clock. The name is relative to the client
  * device; each device is assumed to have n clocks associated with it somehow,
@@ -172,55 +175,49 @@ int clk_get_bulk(struct udevice *dev, struct clk_bulk *bulk);
  * device clock names to provider clocks may be via device-tree properties,
  * board-provided mapping tables, or some other mechanism.
  *
- * @dev:	The client device.
- * @name:	The name of the clock to request, within the client's list of
- *		clocks.
- * @clock:	A pointer to a clock struct to initialize.
  * Return: 0 if OK, or a negative error code.
  */
 int clk_get_by_name(struct udevice *dev, const char *name, struct clk *clk);
 
 /**
  * clk_get_by_name_nodev - Get/request a clock by name without a device.
- *
- * This is a version of clk_get_by_name() that does not use a device.
- *
  * @node:	The client ofnode.
  * @name:	The name of the clock to request, within the client's list of
  *		clocks.
- * @clock:	A pointer to a clock struct to initialize.
+ * @clk:	A pointer to a clock struct to initialize.
+ *
  * Return: 0 if OK, or a negative error code.
  */
 int clk_get_by_name_nodev(ofnode node, const char *name, struct clk *clk);
 
 /**
- * devm_clk_get - lookup and obtain a managed reference to a clock producer.
+ * devm_clk_get() - lookup and obtain a managed reference to a clock producer.
  * @dev: device for clock "consumer"
  * @id: clock consumer ID
  *
- * Returns a struct clk corresponding to the clock producer, or
- * valid IS_ERR() condition containing errno.  The implementation
- * uses @dev and @id to determine the clock consumer, and thereby
- * the clock producer.  (IOW, @id may be identical strings, but
- * clk_get may return different clock producers depending on @dev.)
+ * The implementation uses @dev and @id to determine the clock consumer, and
+ * thereby the clock producer. (IOW, @id may be identical strings, but clk_get
+ * may return different clock producers depending on @dev.)
  *
  * Drivers must assume that the clock source is not enabled.
  *
- * devm_clk_get should not be called from within interrupt context.
- *
  * The clock will automatically be freed when the device is unbound
  * from the bus.
+ *
+ * Return:
+ * a struct clk corresponding to the clock producer, or
+ * valid IS_ERR() condition containing errno
  */
 struct clk *devm_clk_get(struct udevice *dev, const char *id);
 
 /**
- * devm_clk_get_optional - lookup and obtain a managed reference to an optional
- *			   clock producer.
+ * devm_clk_get_optional() - lookup and obtain a managed reference to an
+ *                           optional clock producer.
  * @dev: device for clock "consumer"
  * @id: clock consumer ID
  *
  * Behaves the same as devm_clk_get() except where there is no clock producer.
- * In this case, instead of returning -ENOENT, the function returns NULL.
+ * In this case, instead of returning -%ENOENT, the function returns NULL.
  */
 static inline struct clk *devm_clk_get_optional(struct udevice *dev,
 						const char *id)
@@ -236,13 +233,13 @@ static inline struct clk *devm_clk_get_optional(struct udevice *dev,
 /**
  * clk_release_all() - Disable (turn off)/Free an array of previously
  * requested clocks.
+ * @clk:	A clock struct array that was previously successfully
+ *		requested by clk_request/get_by_*().
+ * @count:	Number of clock contained in the array
  *
  * For each clock contained in the clock array, this function will check if
  * clock has been previously requested and then will disable and free it.
  *
- * @clk:	A clock struct array that was previously successfully
- *		requested by clk_request/get_by_*().
- * @count	Number of clock contained in the array
  * Return: zero on success, or -ve error code.
  */
 int clk_release_all(struct clk *clk, int count);
@@ -294,13 +291,12 @@ static inline int clk_release_all(struct clk *clk, int count)
  * clk_get_by_name_nodev_optional - Get/request an optinonal clock by name
  *		without a device.
  * @node:	The client ofnode.
- * @name:	The name of the clock to request.
  * @name:	The name of the clock to request, within the client's list of
  *		clocks.
- * @clock:	A pointer to a clock struct to initialize.
+ * @clk:	A pointer to a clock struct to initialize.
  *
  * Behaves the same as clk_get_by_name_nodev() except where there is
- * no clock producer, in this case, skip the error number -ENODATA, and
+ * no clock producer, in this case, skip the error number -%ENODATA, and
  * the function returns 0.
  */
 static inline int clk_get_by_name_nodev_optional(ofnode node, const char *name,
@@ -340,12 +336,13 @@ enum clk_defaults_stage {
 
 #if CONFIG_IS_ENABLED(OF_REAL) && CONFIG_IS_ENABLED(CLK)
 /**
- * clk_set_defaults - Process 'assigned-{clocks/clock-parents/clock-rates}'
+ * clk_set_defaults - Process ``assigned-{clocks/clock-parents/clock-rates}``
  *                    properties to configure clocks
- *
  * @dev:        A device to process (the ofnode associated with this device
  *              will be processed).
  * @stage:	The stage of the probing process this function is called during.
+ *
+ * Return: zero on success, or -ve error code.
  */
 int clk_set_defaults(struct udevice *dev, enum clk_defaults_stage stage);
 #else
@@ -358,12 +355,12 @@ static inline int clk_set_defaults(struct udevice *dev, int stage)
 /**
  * clk_release_bulk() - Disable (turn off)/Free an array of previously
  * requested clocks in a clock bulk struct.
+ * @bulk:	A clock bulk struct that was previously successfully
+ *		requested by clk_get_bulk().
  *
  * For each clock contained in the clock bulk struct, this function will check
  * if clock has been previously requested and then will disable and free it.
  *
- * @clk:	A clock bulk struct that was previously successfully
- *		requested by clk_get_bulk().
  * Return: zero on success, or -ve error code.
  */
 static inline int clk_release_bulk(struct clk_bulk *bulk)
@@ -373,35 +370,35 @@ static inline int clk_release_bulk(struct clk_bulk *bulk)
 
 #if CONFIG_IS_ENABLED(CLK)
 /**
- * clk_request - Request a clock by provider-specific ID.
+ * clk_request() - Request a clock by provider-specific ID.
+ * @dev:	The clock provider device.
+ * @clk:	A pointer to a clock struct to initialize. The caller must
+ *		have already initialized any field in this struct which the
+ *		clock provider uses to identify the clock.
  *
  * This requests a clock using a provider-specific ID. Generally, this function
  * should not be used, since clk_get_by_index/name() provide an interface that
  * better separates clients from intimate knowledge of clock providers.
  * However, this function may be useful in core SoC-specific code.
  *
- * @dev:	The clock provider device.
- * @clock:	A pointer to a clock struct to initialize. The caller must
- *		have already initialized any field in this struct which the
- *		clock provider uses to identify the clock.
  * Return: 0 if OK, or a negative error code.
  */
 int clk_request(struct udevice *dev, struct clk *clk);
 
 /**
- * clk_free - Free a previously requested clock.
- *
- * @clock:	A clock struct that was previously successfully requested by
+ * clk_free() - Free a previously requested clock.
+ * @clk:	A clock struct that was previously successfully requested by
  *		clk_request/get_by_*().
+ *
  * Return: 0 if OK, or a negative error code.
  */
 int clk_free(struct clk *clk);
 
 /**
  * clk_get_rate() - Get current clock rate.
- *
  * @clk:	A clock struct that was previously successfully requested by
  *		clk_request/get_by_*().
+ *
  * Return: clock rate in Hz on success, 0 for invalid clock, or -ve error code
  *	   for other errors.
  */
@@ -409,98 +406,98 @@ ulong clk_get_rate(struct clk *clk);
 
 /**
  * clk_get_parent() - Get current clock's parent.
- *
  * @clk:	A clock struct that was previously successfully requested by
  *		clk_request/get_by_*().
+ *
  * Return: pointer to parent's struct clk, or error code passed as pointer
  */
 struct clk *clk_get_parent(struct clk *clk);
 
 /**
  * clk_get_parent_rate() - Get parent of current clock rate.
- *
  * @clk:	A clock struct that was previously successfully requested by
  *		clk_request/get_by_*().
+ *
  * Return: clock rate in Hz, or -ve error code.
  */
 long long clk_get_parent_rate(struct clk *clk);
 
 /**
  * clk_round_rate() - Adjust a rate to the exact rate a clock can provide
+ * @clk: A clock struct that was previously successfully requested by
+ *       clk_request/get_by_*().
+ * @rate: desired clock rate in Hz.
  *
  * This answers the question "if I were to pass @rate to clk_set_rate(),
  * what clock rate would I end up with?" without changing the hardware
- * in any way.  In other words:
+ * in any way. In other words::
  *
  *   rate = clk_round_rate(clk, r);
  *
- * and:
+ * and::
  *
  *   rate = clk_set_rate(clk, r);
  *
  * are equivalent except the former does not modify the clock hardware
  * in any way.
  *
- * @clk: A clock struct that was previously successfully requested by
- *       clk_request/get_by_*().
- * @rate: desired clock rate in Hz.
  * Return: rounded rate in Hz, or -ve error code.
  */
 ulong clk_round_rate(struct clk *clk, ulong rate);
 
 /**
  * clk_set_rate() - Set current clock rate.
- *
  * @clk:	A clock struct that was previously successfully requested by
  *		clk_request/get_by_*().
  * @rate:	New clock rate in Hz.
+ *
  * Return: new rate, or -ve error code.
  */
 ulong clk_set_rate(struct clk *clk, ulong rate);
 
 /**
  * clk_set_parent() - Set current clock parent.
- *
  * @clk:	A clock struct that was previously successfully requested by
  *		clk_request/get_by_*().
  * @parent:	A clock struct that was previously successfully requested by
  *		clk_request/get_by_*().
+ *
  * Return: new rate, or -ve error code.
  */
 int clk_set_parent(struct clk *clk, struct clk *parent);
 
 /**
  * clk_enable() - Enable (turn on) a clock.
- *
  * @clk:	A clock struct that was previously successfully requested by
  *		clk_request/get_by_*().
+ *
  * Return: zero on success, or -ve error code.
  */
 int clk_enable(struct clk *clk);
 
 /**
  * clk_enable_bulk() - Enable (turn on) all clocks in a clock bulk struct.
- *
  * @bulk:	A clock bulk struct that was previously successfully requested
  *		by clk_get_bulk().
+ *
  * Return: zero on success, or -ve error code.
  */
 int clk_enable_bulk(struct clk_bulk *bulk);
 
 /**
  * clk_disable() - Disable (turn off) a clock.
- *
  * @clk:	A clock struct that was previously successfully requested by
  *		clk_request/get_by_*().
+ *
  * Return: zero on success, or -ve error code.
  */
 int clk_disable(struct clk *clk);
 
 /**
  * clk_disable_bulk() - Disable (turn off) all clocks in a clock bulk struct.
- *
  * @bulk:	A clock bulk struct that was previously successfully requested
  *		by clk_get_bulk().
+ *
  * Return: zero on success, or -ve error code.
  */
 int clk_disable_bulk(struct clk_bulk *bulk);
@@ -510,28 +507,25 @@ int clk_disable_bulk(struct clk_bulk *bulk);
  * @p: clk compared against q
  * @q: clk compared against p
  *
- * Returns true if the two struct clk pointers both point to the same hardware
- * clock node.
- *
- * Returns false otherwise. Note that two NULL clks are treated as matching.
+ * Return:
+ * %true if the two struct clk pointers both point to the same hardware clock
+ * node, and %false otherwise. Note that two %NULL clks are treated as matching.
  */
 bool clk_is_match(const struct clk *p, const struct clk *q);
 
 /**
  * clk_get_by_id() - Get the clock by its ID
- *
  * @id:	The clock ID to search for
- *
  * @clkp:	A pointer to clock struct that has been found among added clocks
  *              to UCLASS_CLK
+ *
  * Return: zero on success, or -ENOENT on error
  */
 int clk_get_by_id(ulong id, struct clk **clkp);
 
 /**
  * clk_dev_binded() - Check whether the clk has a device binded
- *
- * @clk		A pointer to the clk
+ * @clk:	A pointer to the clk
  *
  * Return: true on binded, or false on no
  */
@@ -617,8 +611,8 @@ static inline bool clk_dev_binded(struct clk *clk)
 
 /**
  * clk_valid() - check if clk is valid
- *
  * @clk:	the clock to check
+ *
  * Return: true if valid, or false
  */
 static inline bool clk_valid(struct clk *clk)