/* SPDX-License-Identifier: GPL-2.0+ */

  /*
   * Copyright (c) 2015 Google, Inc
   * Written by Simon Glass <sjg@chromium.org>

   * Copyright (c) 2016, NVIDIA CORPORATION.

   */

  #ifndef _CLK_H_
  #define _CLK_H_

  #include <dm/ofnode.h>

  #include <linux/errno.h>

  #include <linux/types.h>

  /**
   * 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
   * externally to the HW module consuming them, by an entity this API calls a
   * clock provider. This API provides a standard means for drivers to enable and
   * disable clocks, and to set the rate at which they oscillate.
   *

   * A driver that implements UCLASS_CLK is a clock provider. A provider will

   * often implement multiple separate clocks, since the hardware it manages

   * often has this capability. clk-uclass.h describes the interface which

   * clock providers must implement.
   *
   * Clock consumers/clients are the HW modules driven by the clock signals. This
   * header file describes the API used by drivers for those HW modules.
   */

  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_)
   *         Clock IP blocks specific flags (i.e. mux, div, gate, etc) are defined
   *         in struct's for those devices (e.g. struct clk_mux).

   * @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.

   *

   * 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
   * information, or (b) replace the id field with an opaque pointer, which the
   * provider would dynamically allocated during its .of_xlate op, and process
   * during is .request op. This may require the addition of an extra op to clean
   * up the allocation.
   */
  struct clk {
  	struct udevice *dev;

  	long long rate;	/* in HZ */

  	u32 flags;

  	int enable_count;

  	/*

  	 * Written by of_xlate. In the future, we might add more fields here.

  	 */

  	unsigned long id;

  	unsigned long data;

  };

  /**
   * struct clk_bulk - A handle to (allowing control of) a bulk of clocks.
   *
   * 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;
  	unsigned int count;
  };

  #if CONFIG_IS_ENABLED(OF_CONTROL) && CONFIG_IS_ENABLED(CLK)

  struct phandle_1_arg;

  int clk_get_by_index_platdata(struct udevice *dev, int index,

  			      struct phandle_1_arg *cells, struct clk *clk);

  /**
   * clock_get_by_index - Get/request a clock by integer index.
   *
   * 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,
   * and this function finds and requests one of them. The mapping of client
   * 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);

  
  /**

   * clock_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.
   *
   * @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.
   * @return 0 if OK, or a negative error code.
   */
  int clk_get_by_index_nodev(ofnode node, int index, struct clk *clk);
  
  /**

   * clock_get_bulk - Get/request all clocks of a device.
   *
   * 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
   * and requests all of them in a separate structure. The mapping of client
   * 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);
  
  /**

   * clock_get_by_name - Get/request a clock by name.

   *

   * 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,
   * and this function finds and requests one of them. The mapping of client
   * 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.
   * @return 0 if OK, or a negative error code.
   */
  int clk_get_by_name_nodev(ofnode node, const char *name, struct clk *clk);
  
  /**
   * clock_get_optional_nodev - 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.
   *
   * 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
   * the function returns 0.
   */
  int clk_get_optional_nodev(ofnode node, const char *name, struct clk *clk);
  
  /**

   * 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.)
   *
   * 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.
   */
  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.
   * @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.
   */
  struct clk *devm_clk_get_optional(struct udevice *dev, const char *id);
  
  /**

   * clk_release_all() - Disable (turn off)/Free an array of previously
   * requested clocks.
   *
   * 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);

  /**
   * devm_clk_put	- "free" a managed clock source
   * @dev: device used to acquire the clock
   * @clk: clock source acquired with devm_clk_get()
   *
   * Note: drivers must ensure that all clk_enable calls made on this
   * clock source are balanced by clk_disable calls prior to calling
   * this function.
   *
   * clk_put should not be called from within interrupt context.
   */
  void devm_clk_put(struct udevice *dev, struct clk *clk);

  #else
  static inline int clk_get_by_index(struct udevice *dev, int index,
  				   struct clk *clk)
  {
  	return -ENOSYS;
  }

  static inline int clk_get_bulk(struct udevice *dev, struct clk_bulk *bulk)
  {
  	return -ENOSYS;
  }

  static inline int clk_get_by_name(struct udevice *dev, const char *name,
  			   struct clk *clk)
  {
  	return -ENOSYS;
  }

  static inline int
  clk_get_by_name_nodev(ofnode node, const char *name, struct clk *clk)
  {
  	return -ENOSYS;
  }
  
  static inline int
  clk_get_optional_nodev(ofnode node, const char *name, struct clk *clk)
  {
  	return -ENOSYS;
  }

  static inline int clk_release_all(struct clk *clk, int count)
  {
  	return -ENOSYS;
  }

  #endif

  #if (CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)) && \
  	CONFIG_IS_ENABLED(CLK)
  /**
   * 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:	A integer. 0 indicates that this is called before the device
   *		is probed. 1 indicates that this is called just after the
   *		device has been probed

   */

  int clk_set_defaults(struct udevice *dev, int stage);

  #else

  static inline int clk_set_defaults(struct udevice *dev, int stage)

  {
  	return 0;
  }
  #endif

  /**

   * clk_release_bulk() - Disable (turn off)/Free an array of previously
   * requested clocks in a clock bulk struct.
   *
   * 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)
  {
  	return clk_release_all(bulk->clks, bulk->count);
  }
  
  /**

   * clk_request - Request a clock by provider-specific ID.

   *

   * 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);

  
  /**

   * clock_free - Free a previously requested clock.

   *

   * @clock:	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, or -ve error code.

   */

  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_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);

  /**
   * clk_is_match - check if two clk's point to the same hardware clock
   * @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.
   */
  bool clk_is_match(const struct clk *p, const struct clk *q);

  int soc_clk_dump(void);

  /**
   * 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)
  {

  	return clk && !!clk->dev;

  }

  
  /**
   * 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
   *
   * @return true on binded, or false on no
   */
  bool clk_dev_binded(struct clk *clk);

  #endif

  
  #define clk_prepare_enable(clk) clk_enable(clk)
  #define clk_disable_unprepare(clk) clk_disable(clk)