ticker_api.h

00001 
00002 /** \addtogroup hal */
00003 /** @{*/
00004 /* mbed Microcontroller Library
00005  * Copyright (c) 2015 ARM Limited
00006  *
00007  * Licensed under the Apache License, Version 2.0 (the "License");
00008  * you may not use this file except in compliance with the License.
00009  * You may obtain a copy of the License at
00010  *
00011  *     http://www.apache.org/licenses/LICENSE-2.0
00012  *
00013  * Unless required by applicable law or agreed to in writing, software
00014  * distributed under the License is distributed on an "AS IS" BASIS,
00015  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00016  * See the License for the specific language governing permissions and
00017  * limitations under the License.
00018  */
00019 #ifndef MBED_TICKER_API_H
00020 #define MBED_TICKER_API_H
00021 
00022 #include <stdint.h>
00023 #include "device.h"
00024 
00025 typedef uint32_t timestamp_t;
00026 
00027 /** Ticker's event structure
00028  */
00029 typedef struct ticker_event_s {
00030     timestamp_t            timestamp; /**< Event's timestamp */
00031     uint32_t               id;        /**< TimerEvent object */
00032     struct ticker_event_s *next;      /**< Next event in the queue */
00033 } ticker_event_t;
00034 
00035 typedef void (*ticker_event_handler)(uint32_t id);
00036 
00037 /** Ticker's interface structure - required API for a ticker
00038  */
00039 typedef struct {
00040     void (*init)(void);                           /**< Init function */
00041     uint32_t (*read)(void);                       /**< Read function */
00042     void (*disable_interrupt)(void);              /**< Disable interrupt function */
00043     void (*clear_interrupt)(void);                /**< Clear interrupt function */
00044     void (*set_interrupt)(timestamp_t timestamp); /**< Set interrupt function */
00045 } ticker_interface_t;
00046 
00047 /** Ticker's event queue structure
00048  */
00049 typedef struct {
00050     ticker_event_handler event_handler; /**< Event handler */
00051     ticker_event_t *head;               /**< A pointer to head */
00052 } ticker_event_queue_t;
00053 
00054 /** Ticker's data structure
00055  */
00056 typedef struct {
00057     const ticker_interface_t *interface; /**< Ticker's interface */
00058     ticker_event_queue_t *queue;         /**< Ticker's event queue */
00059 } ticker_data_t;
00060 
00061 #ifdef __cplusplus
00062 extern "C" {
00063 #endif
00064 
00065 /**
00066  * \defgroup hal_ticker Ticker HAL functions
00067  * @{
00068  */
00069 
00070 /** Initialize a ticker and set the event handler
00071  *
00072  * @param data    The ticker's data
00073  * @param handler A handler to be set
00074  */
00075 void ticker_set_handler(const ticker_data_t *const data, ticker_event_handler handler);
00076 
00077 /** IRQ handler that goes through the events to trigger overdue events.
00078  *
00079  * @param data    The ticker's data
00080  */
00081 void ticker_irq_handler(const ticker_data_t *const data);
00082 
00083 /** Remove an event from the queue
00084  *
00085  * @param data The ticker's data
00086  * @param obj  The event object to be removed from the queue
00087  */
00088 void ticker_remove_event(const ticker_data_t *const data, ticker_event_t *obj);
00089 
00090 /** Insert an event to the queue
00091  *
00092  * @param data      The ticker's data
00093  * @param obj       The event object to be inserted to the queue
00094  * @param timestamp The event's timestamp
00095  * @param id        The event object
00096  */
00097 void ticker_insert_event(const ticker_data_t *const data, ticker_event_t *obj, timestamp_t timestamp, uint32_t id);
00098 
00099 /** Read the current ticker's timestamp
00100  *
00101  * @param data The ticker's data
00102  * @return The current timestamp
00103  */
00104 timestamp_t ticker_read(const ticker_data_t *const data);
00105 
00106 /** Read the next event's timestamp
00107  *
00108  * @param data The ticker's data
00109  * @return 1 if timestamp is pending event, 0 if there's no event pending
00110  */
00111 int ticker_get_next_timestamp(const ticker_data_t *const data, timestamp_t *timestamp);
00112 
00113 /**@}*/
00114 
00115 #ifdef __cplusplus
00116 }
00117 #endif
00118 
00119 #endif
00120 
00121 /** @}*/