ticker_api.h

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