blob: c9cd1a9a63b2d10f194f1acf9ea863d8a2f5cce9 [file] [log] [blame]
/* clock_control.h - public clock controller driver API */
/*
* Copyright (c) 2015 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
* @brief Public Clock Control APIs
*/
#ifndef ZEPHYR_INCLUDE_DRIVERS_CLOCK_CONTROL_H_
#define ZEPHYR_INCLUDE_DRIVERS_CLOCK_CONTROL_H_
/**
* @brief Clock Control Interface
* @defgroup clock_control_interface Clock Control Interface
* @ingroup io_interfaces
* @{
*/
#include <zephyr/types.h>
#include <stddef.h>
#include <device.h>
#include <sys/__assert.h>
#include <sys/slist.h>
#ifdef __cplusplus
extern "C" {
#endif
/* Clock control API */
/* Used to select all subsystem of a clock controller */
#define CLOCK_CONTROL_SUBSYS_ALL NULL
/**
* @brief Current clock status.
*/
enum clock_control_status {
CLOCK_CONTROL_STATUS_STARTING,
CLOCK_CONTROL_STATUS_OFF,
CLOCK_CONTROL_STATUS_ON,
CLOCK_CONTROL_STATUS_UNKNOWN
};
/**
* @cond INTERNAL_HIDDEN
*/
#define Z_CLOCK_CONTROL_ASYNC_DATA_INITIALIZER(_cb, _user_data) \
{ \
.cb = cb, \
.user_data = _user_data \
}
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* clock_control_subsys_t is a type to identify a clock controller sub-system.
* Such data pointed is opaque and relevant only to the clock controller
* driver instance being used.
*/
typedef void *clock_control_subsys_t;
/** @brief Callback called on clock started.
*
* @param dev Device structure whose driver controls the clock.
* @param subsys Opaque data representing the clock.
* @param user_data User data.
*/
typedef void (*clock_control_cb_t)(const struct device *dev,
clock_control_subsys_t subsys,
void *user_data);
/**
* Define and initialize clock_control async data.
*
* @param name Name of the data.
* @param cb Callback.
* @param user_data User data
*/
#define CLOCK_CONTROL_ASYNC_DATA_DEFINE(name, cb, user_data) \
struct clock_control_async_data name = \
Z_CLOCK_CONTROL_ASYNC_DATA_INITIALIZER(cb, user_data)
/**
* @brief Clock control data used for asynchronous clock enabling.
*
* @param node Used internally for linking asynchronous requests.
* @param cb Callback called when clock is started.
* @param user_data User data passed as an argument in the callback.
*/
struct clock_control_async_data {
sys_snode_t node;
clock_control_cb_t cb;
void *user_data;
};
typedef int (*clock_control)(const struct device *dev,
clock_control_subsys_t sys);
typedef int (*clock_control_get)(const struct device *dev,
clock_control_subsys_t sys,
uint32_t *rate);
typedef int (*clock_control_async_on_fn)(const struct device *dev,
clock_control_subsys_t sys,
struct clock_control_async_data *data);
typedef enum clock_control_status (*clock_control_get_status_fn)(const struct device *dev,
clock_control_subsys_t sys);
struct clock_control_driver_api {
clock_control on;
clock_control off;
clock_control_async_on_fn async_on;
clock_control_get get_rate;
clock_control_get_status_fn get_status;
};
/**
* @brief Enable a clock controlled by the device
*
* On success, the clock is enabled and ready when this function
* returns. This function may sleep, and thus can only be called from
* thread context.
*
* Use @ref clock_control_async_on() for non-blocking operation.
*
* @param dev Device structure whose driver controls the clock.
* @param sys Opaque data representing the clock.
* @return 0 on success, negative errno on failure.
*/
static inline int clock_control_on(const struct device *dev,
clock_control_subsys_t sys)
{
const struct clock_control_driver_api *api =
(const struct clock_control_driver_api *)dev->api;
return api->on(dev, sys);
}
/**
* @brief Disable a clock controlled by the device
*
* This function is non-blocking and can be called from any context.
* On success, the clock is disabled when this function returns.
*
* @param dev Device structure whose driver controls the clock
* @param sys Opaque data representing the clock
* @return 0 on success, negative errno on failure.
*/
static inline int clock_control_off(const struct device *dev,
clock_control_subsys_t sys)
{
const struct clock_control_driver_api *api =
(const struct clock_control_driver_api *)dev->api;
return api->off(dev, sys);
}
/**
* @brief Request clock to start with notification when clock has been started.
*
* Function is non-blocking and can be called from any context.
* When clock is already running user callback will be called from the context
* of the function call else it is called from other context (e.g. clock
* interrupt).
*
* @param dev Device.
* @param sys A pointer to an opaque data representing the sub-system.
* @param data Data structure containing a callback that is called when
* action is performed. Structure content must be valid until
* clock is started and user callback is called. Can be NULL.
*
* @retval 0 if clock is started or already running.
* @retval -EBUSY if same request already scheduled and not yet completed.
* @retval -ENOTSUP if not supported.
*/
static inline int clock_control_async_on(const struct device *dev,
clock_control_subsys_t sys,
struct clock_control_async_data *data)
{
const struct clock_control_driver_api *api =
(const struct clock_control_driver_api *)dev->api;
if (!api->async_on) {
return -ENOTSUP;
}
return api->async_on(dev, sys, data);
}
/**
* @brief Get clock status.
*
* @param dev Device.
* @param sys A pointer to an opaque data representing the sub-system.
*
* @return Status.
*/
static inline enum clock_control_status clock_control_get_status(const struct device *dev,
clock_control_subsys_t sys)
{
const struct clock_control_driver_api *api =
(const struct clock_control_driver_api *)dev->api;
if (!api->get_status) {
return CLOCK_CONTROL_STATUS_UNKNOWN;
}
return api->get_status(dev, sys);
}
/**
* @brief Obtain the clock rate of given sub-system
* @param dev Pointer to the device structure for the clock controller driver
* instance
* @param sys A pointer to an opaque data representing the sub-system
* @param[out] rate Subsystem clock rate
*/
static inline int clock_control_get_rate(const struct device *dev,
clock_control_subsys_t sys,
uint32_t *rate)
{
const struct clock_control_driver_api *api =
(const struct clock_control_driver_api *)dev->api;
__ASSERT(api->get_rate != NULL, "%s not implemented for device %s",
__func__, dev->name);
return api->get_rate(dev, sys, rate);
}
#ifdef __cplusplus
}
#endif
/**
* @}
*/
#endif /* ZEPHYR_INCLUDE_DRIVERS_CLOCK_CONTROL_H_ */