Al Williams / nRF51822Copy

Copy of nRF51822 library

Fork of nRF51822 by Nordic Semiconductor

nordic/app_common/app_scheduler.c@61:6fb5c2c43d35, 2014-09-21 (annotated)

Committer:
wd5gnr
Date:
Sun Sep 21 19:21:08 2014 +0000
Revision:
61:6fb5c2c43d35
Parent:
46:2bfbbe290083 
First commit

Who changed what in which revision?

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Rohit Grover 46:2bfbbe290083 1 /* Copyright (c) 2012 Nordic Semiconductor. All Rights Reserved.
Rohit Grover 46:2bfbbe290083 2 *
Rohit Grover 46:2bfbbe290083 3 * The information contained herein is property of Nordic Semiconductor ASA.
Rohit Grover 46:2bfbbe290083 4 * Terms and conditions of usage are described in detail in NORDIC
Rohit Grover 46:2bfbbe290083 5 * SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
Rohit Grover 46:2bfbbe290083 6 *
Rohit Grover 46:2bfbbe290083 7 * Licensees are granted free, non-transferable use of the information. NO
Rohit Grover 46:2bfbbe290083 8 * WARRANTY of ANY KIND is provided. This heading must NOT be removed from
Rohit Grover 46:2bfbbe290083 9 * the file.
Rohit Grover 46:2bfbbe290083 10 *
Rohit Grover 46:2bfbbe290083 11 */
Rohit Grover 46:2bfbbe290083 12
Rohit Grover 46:2bfbbe290083 13 #include "app_scheduler.h"
Rohit Grover 46:2bfbbe290083 14 #include <stdlib.h>
Rohit Grover 46:2bfbbe290083 15 #include <stdint.h>
Rohit Grover 46:2bfbbe290083 16 #include <string.h>
Rohit Grover 46:2bfbbe290083 17 #include "nrf_soc.h"
Rohit Grover 46:2bfbbe290083 18 #include "nrf_assert.h"
Rohit Grover 46:2bfbbe290083 19 #include "app_util.h"
Rohit Grover 46:2bfbbe290083 20 #include "app_util_platform.h"
Rohit Grover 46:2bfbbe290083 21
Rohit Grover 46:2bfbbe290083 22 /**@brief Structure for holding a scheduled event header. */
Rohit Grover 46:2bfbbe290083 23 typedef struct
Rohit Grover 46:2bfbbe290083 24 {
Rohit Grover 46:2bfbbe290083 25 app_sched_event_handler_t handler; /**< Pointer to event handler to receive the event. */
Rohit Grover 46:2bfbbe290083 26 uint16_t event_data_size; /**< Size of event data. */
Rohit Grover 46:2bfbbe290083 27 } event_header_t;
Rohit Grover 46:2bfbbe290083 28
Rohit Grover 46:2bfbbe290083 29 STATIC_ASSERT(sizeof(event_header_t) <= APP_SCHED_EVENT_HEADER_SIZE);
Rohit Grover 46:2bfbbe290083 30
Rohit Grover 46:2bfbbe290083 31 static event_header_t * m_queue_event_headers; /**< Array for holding the queue event headers. */
Rohit Grover 46:2bfbbe290083 32 static uint8_t * m_queue_event_data; /**< Array for holding the queue event data. */
Rohit Grover 46:2bfbbe290083 33 static volatile uint8_t m_queue_start_index; /**< Index of queue entry at the start of the queue. */
Rohit Grover 46:2bfbbe290083 34 static volatile uint8_t m_queue_end_index; /**< Index of queue entry at the end of the queue. */
Rohit Grover 46:2bfbbe290083 35 static uint16_t m_queue_event_size; /**< Maximum event size in queue. */
Rohit Grover 46:2bfbbe290083 36 static uint16_t m_queue_size; /**< Number of queue entries. */
Rohit Grover 46:2bfbbe290083 37
Rohit Grover 46:2bfbbe290083 38 /**@brief Macro for checking if a queue is full. */
Rohit Grover 46:2bfbbe290083 39 #define APP_SCHED_QUEUE_FULL() (next_index(m_queue_end_index) == m_queue_start_index)
Rohit Grover 46:2bfbbe290083 40
Rohit Grover 46:2bfbbe290083 41 /**@brief Macro for checking if a queue is empty. */
Rohit Grover 46:2bfbbe290083 42 #define APP_SCHED_QUEUE_EMPTY() (m_queue_end_index == m_queue_start_index)
Rohit Grover 46:2bfbbe290083 43
Rohit Grover 46:2bfbbe290083 44
Rohit Grover 46:2bfbbe290083 45 /**@brief Function for incrementing a queue index, and handle wrap-around.
Rohit Grover 46:2bfbbe290083 46 *
Rohit Grover 46:2bfbbe290083 47 * @param[in] index Old index.
Rohit Grover 46:2bfbbe290083 48 *
Rohit Grover 46:2bfbbe290083 49 * @return New (incremented) index.
Rohit Grover 46:2bfbbe290083 50 */
Rohit Grover 46:2bfbbe290083 51 static __INLINE uint8_t next_index(uint8_t index)
Rohit Grover 46:2bfbbe290083 52 {
Rohit Grover 46:2bfbbe290083 53 return (index < m_queue_size) ? (index + 1) : 0;
Rohit Grover 46:2bfbbe290083 54 }
Rohit Grover 46:2bfbbe290083 55
Rohit Grover 46:2bfbbe290083 56
Rohit Grover 46:2bfbbe290083 57 uint32_t app_sched_init(uint16_t event_size, uint16_t queue_size, void * p_event_buffer)
Rohit Grover 46:2bfbbe290083 58 {
Rohit Grover 46:2bfbbe290083 59 uint16_t data_start_index = (queue_size + 1) * sizeof(event_header_t);
Rohit Grover 46:2bfbbe290083 60
Rohit Grover 46:2bfbbe290083 61 // Check that buffer is correctly aligned
Rohit Grover 46:2bfbbe290083 62 if (!is_word_aligned(p_event_buffer))
Rohit Grover 46:2bfbbe290083 63 {
Rohit Grover 46:2bfbbe290083 64 return NRF_ERROR_INVALID_PARAM;
Rohit Grover 46:2bfbbe290083 65 }
Rohit Grover 46:2bfbbe290083 66
Rohit Grover 46:2bfbbe290083 67 // Initialize event scheduler
Rohit Grover 46:2bfbbe290083 68 m_queue_event_headers = p_event_buffer;
Rohit Grover 46:2bfbbe290083 69 m_queue_event_data = &((uint8_t *)p_event_buffer)[data_start_index];
Rohit Grover 46:2bfbbe290083 70 m_queue_end_index = 0;
Rohit Grover 46:2bfbbe290083 71 m_queue_start_index = 0;
Rohit Grover 46:2bfbbe290083 72 m_queue_event_size = event_size;
Rohit Grover 46:2bfbbe290083 73 m_queue_size = queue_size;
Rohit Grover 46:2bfbbe290083 74
Rohit Grover 46:2bfbbe290083 75 return NRF_SUCCESS;
Rohit Grover 46:2bfbbe290083 76 }
Rohit Grover 46:2bfbbe290083 77
Rohit Grover 46:2bfbbe290083 78
Rohit Grover 46:2bfbbe290083 79 uint32_t app_sched_event_put(void * p_event_data,
Rohit Grover 46:2bfbbe290083 80 uint16_t event_data_size,
Rohit Grover 46:2bfbbe290083 81 app_sched_event_handler_t handler)
Rohit Grover 46:2bfbbe290083 82 {
Rohit Grover 46:2bfbbe290083 83 uint32_t err_code;
Rohit Grover 46:2bfbbe290083 84
Rohit Grover 46:2bfbbe290083 85 if (event_data_size <= m_queue_event_size)
Rohit Grover 46:2bfbbe290083 86 {
Rohit Grover 46:2bfbbe290083 87 uint16_t event_index = 0xFFFF;
Rohit Grover 46:2bfbbe290083 88
Rohit Grover 46:2bfbbe290083 89 CRITICAL_REGION_ENTER();
Rohit Grover 46:2bfbbe290083 90
Rohit Grover 46:2bfbbe290083 91 if (!APP_SCHED_QUEUE_FULL())
Rohit Grover 46:2bfbbe290083 92 {
Rohit Grover 46:2bfbbe290083 93 event_index = m_queue_end_index;
Rohit Grover 46:2bfbbe290083 94 m_queue_end_index = next_index(m_queue_end_index);
Rohit Grover 46:2bfbbe290083 95 }
Rohit Grover 46:2bfbbe290083 96
Rohit Grover 46:2bfbbe290083 97 CRITICAL_REGION_EXIT();
Rohit Grover 46:2bfbbe290083 98
Rohit Grover 46:2bfbbe290083 99 if (event_index != 0xFFFF)
Rohit Grover 46:2bfbbe290083 100 {
Rohit Grover 46:2bfbbe290083 101 // NOTE: This can be done outside the critical region since the event consumer will
Rohit Grover 46:2bfbbe290083 102 // always be called from the main loop, and will thus never interrupt this code.
Rohit Grover 46:2bfbbe290083 103 m_queue_event_headers[event_index].handler = handler;
Rohit Grover 46:2bfbbe290083 104 if ((p_event_data != NULL) && (event_data_size > 0))
Rohit Grover 46:2bfbbe290083 105 {
Rohit Grover 46:2bfbbe290083 106 memcpy(&m_queue_event_data[event_index * m_queue_event_size],
Rohit Grover 46:2bfbbe290083 107 p_event_data,
Rohit Grover 46:2bfbbe290083 108 event_data_size);
Rohit Grover 46:2bfbbe290083 109 m_queue_event_headers[event_index].event_data_size = event_data_size;
Rohit Grover 46:2bfbbe290083 110 }
Rohit Grover 46:2bfbbe290083 111 else
Rohit Grover 46:2bfbbe290083 112 {
Rohit Grover 46:2bfbbe290083 113 m_queue_event_headers[event_index].event_data_size = 0;
Rohit Grover 46:2bfbbe290083 114 }
Rohit Grover 46:2bfbbe290083 115
Rohit Grover 46:2bfbbe290083 116 err_code = NRF_SUCCESS;
Rohit Grover 46:2bfbbe290083 117 }
Rohit Grover 46:2bfbbe290083 118 else
Rohit Grover 46:2bfbbe290083 119 {
Rohit Grover 46:2bfbbe290083 120 err_code = NRF_ERROR_NO_MEM;
Rohit Grover 46:2bfbbe290083 121 }
Rohit Grover 46:2bfbbe290083 122 }
Rohit Grover 46:2bfbbe290083 123 else
Rohit Grover 46:2bfbbe290083 124 {
Rohit Grover 46:2bfbbe290083 125 err_code = NRF_ERROR_INVALID_LENGTH;
Rohit Grover 46:2bfbbe290083 126 }
Rohit Grover 46:2bfbbe290083 127
Rohit Grover 46:2bfbbe290083 128 return err_code;
Rohit Grover 46:2bfbbe290083 129 }
Rohit Grover 46:2bfbbe290083 130
Rohit Grover 46:2bfbbe290083 131
Rohit Grover 46:2bfbbe290083 132 /**@brief Function for reading the next event from specified event queue.
Rohit Grover 46:2bfbbe290083 133 *
Rohit Grover 46:2bfbbe290083 134 * @param[out] pp_event_data Pointer to pointer to event data.
Rohit Grover 46:2bfbbe290083 135 * @param[out] p_event_data_size Pointer to size of event data.
Rohit Grover 46:2bfbbe290083 136 * @param[out] p_event_handler Pointer to event handler function pointer.
Rohit Grover 46:2bfbbe290083 137 *
Rohit Grover 46:2bfbbe290083 138 * @return NRF_SUCCESS if new event, NRF_ERROR_NOT_FOUND if event queue is empty.
Rohit Grover 46:2bfbbe290083 139 */
Rohit Grover 46:2bfbbe290083 140 static uint32_t app_sched_event_get(void ** pp_event_data,
Rohit Grover 46:2bfbbe290083 141 uint16_t * p_event_data_size,
Rohit Grover 46:2bfbbe290083 142 app_sched_event_handler_t * p_event_handler)
Rohit Grover 46:2bfbbe290083 143 {
Rohit Grover 46:2bfbbe290083 144 uint32_t err_code = NRF_ERROR_NOT_FOUND;
Rohit Grover 46:2bfbbe290083 145
Rohit Grover 46:2bfbbe290083 146 if (!APP_SCHED_QUEUE_EMPTY())
Rohit Grover 46:2bfbbe290083 147 {
Rohit Grover 46:2bfbbe290083 148 uint16_t event_index;
Rohit Grover 46:2bfbbe290083 149
Rohit Grover 46:2bfbbe290083 150 // NOTE: There is no need for a critical region here, as this function will only be called
Rohit Grover 46:2bfbbe290083 151 // from app_sched_execute() from inside the main loop, so it will never interrupt
Rohit Grover 46:2bfbbe290083 152 // app_sched_event_put(). Also, updating of (i.e. writing to) the start index will be
Rohit Grover 46:2bfbbe290083 153 // an atomic operation.
Rohit Grover 46:2bfbbe290083 154 event_index = m_queue_start_index;
Rohit Grover 46:2bfbbe290083 155 m_queue_start_index = next_index(m_queue_start_index);
Rohit Grover 46:2bfbbe290083 156
Rohit Grover 46:2bfbbe290083 157 *pp_event_data = &m_queue_event_data[event_index * m_queue_event_size];
Rohit Grover 46:2bfbbe290083 158 *p_event_data_size = m_queue_event_headers[event_index].event_data_size;
Rohit Grover 46:2bfbbe290083 159 *p_event_handler = m_queue_event_headers[event_index].handler;
Rohit Grover 46:2bfbbe290083 160
Rohit Grover 46:2bfbbe290083 161 err_code = NRF_SUCCESS;
Rohit Grover 46:2bfbbe290083 162 }
Rohit Grover 46:2bfbbe290083 163
Rohit Grover 46:2bfbbe290083 164 return err_code;
Rohit Grover 46:2bfbbe290083 165 }
Rohit Grover 46:2bfbbe290083 166
Rohit Grover 46:2bfbbe290083 167
Rohit Grover 46:2bfbbe290083 168 void app_sched_execute(void)
Rohit Grover 46:2bfbbe290083 169 {
Rohit Grover 46:2bfbbe290083 170 void * p_event_data;
Rohit Grover 46:2bfbbe290083 171 uint16_t event_data_size;
Rohit Grover 46:2bfbbe290083 172 app_sched_event_handler_t event_handler;
Rohit Grover 46:2bfbbe290083 173
Rohit Grover 46:2bfbbe290083 174 // Get next event (if any), and execute handler
Rohit Grover 46:2bfbbe290083 175 while ((app_sched_event_get(&p_event_data, &event_data_size, &event_handler) == NRF_SUCCESS))
Rohit Grover 46:2bfbbe290083 176 {
Rohit Grover 46:2bfbbe290083 177 event_handler(p_event_data, event_data_size);
Rohit Grover 46:2bfbbe290083 178 }
Rohit Grover 46:2bfbbe290083 179 }