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drivers/SPI.cpp@174:ed647f63e28d, 2017-12-19 (annotated)

Committer:
Dollyparton
Date:
Tue Dec 19 12:50:13 2017 +0000
Revision:
174:ed647f63e28d
Parent:
170:19eb464bc2be 
Added RAW socket.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 149:156823d33999 1 /* mbed Microcontroller Library
<> 149:156823d33999 2 * Copyright (c) 2006-2013 ARM Limited
<> 149:156823d33999 3 *
<> 149:156823d33999 4 * Licensed under the Apache License, Version 2.0 (the "License");
<> 149:156823d33999 5 * you may not use this file except in compliance with the License.
<> 149:156823d33999 6 * You may obtain a copy of the License at
<> 149:156823d33999 7 *
<> 149:156823d33999 8 * http://www.apache.org/licenses/LICENSE-2.0
<> 149:156823d33999 9 *
<> 149:156823d33999 10 * Unless required by applicable law or agreed to in writing, software
<> 149:156823d33999 11 * distributed under the License is distributed on an "AS IS" BASIS,
<> 149:156823d33999 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
<> 149:156823d33999 13 * See the License for the specific language governing permissions and
<> 149:156823d33999 14 * limitations under the License.
<> 149:156823d33999 15 */
<> 149:156823d33999 16 #include "drivers/SPI.h"
<> 160:d5399cc887bb 17 #include "platform/mbed_critical.h"
<> 149:156823d33999 18
<> 149:156823d33999 19 #if DEVICE_SPI
<> 149:156823d33999 20
<> 149:156823d33999 21 namespace mbed {
<> 149:156823d33999 22
<> 149:156823d33999 23 #if DEVICE_SPI_ASYNCH && TRANSACTION_QUEUE_SIZE_SPI
<> 149:156823d33999 24 CircularBuffer<Transaction<SPI>, TRANSACTION_QUEUE_SIZE_SPI> SPI::_transaction_buffer;
<> 149:156823d33999 25 #endif
<> 149:156823d33999 26
<> 149:156823d33999 27 SPI::SPI(PinName mosi, PinName miso, PinName sclk, PinName ssel) :
<> 149:156823d33999 28 _spi(),
<> 149:156823d33999 29 #if DEVICE_SPI_ASYNCH
<> 149:156823d33999 30 _irq(this),
<> 149:156823d33999 31 _usage(DMA_USAGE_NEVER),
<> 149:156823d33999 32 #endif
<> 149:156823d33999 33 _bits(8),
<> 149:156823d33999 34 _mode(0),
Kojto 170:19eb464bc2be 35 _hz(1000000),
Kojto 170:19eb464bc2be 36 _write_fill(SPI_FILL_CHAR) {
<> 149:156823d33999 37 // No lock needed in the constructor
<> 149:156823d33999 38
<> 149:156823d33999 39 spi_init(&_spi, mosi, miso, sclk, ssel);
Kojto 169:e3b6fe271b81 40 _acquire();
<> 149:156823d33999 41 }
<> 149:156823d33999 42
<> 149:156823d33999 43 void SPI::format(int bits, int mode) {
<> 149:156823d33999 44 lock();
<> 149:156823d33999 45 _bits = bits;
<> 149:156823d33999 46 _mode = mode;
Kojto 169:e3b6fe271b81 47 // If changing format while you are the owner than just
Kojto 169:e3b6fe271b81 48 // update format, but if owner is changed than even frequency should be
Kojto 169:e3b6fe271b81 49 // updated which is done by acquire.
Kojto 169:e3b6fe271b81 50 if (_owner == this) {
Kojto 169:e3b6fe271b81 51 spi_format(&_spi, _bits, _mode, 0);
Kojto 169:e3b6fe271b81 52 } else {
Kojto 169:e3b6fe271b81 53 _acquire();
Kojto 169:e3b6fe271b81 54 }
<> 149:156823d33999 55 unlock();
<> 149:156823d33999 56 }
<> 149:156823d33999 57
<> 149:156823d33999 58 void SPI::frequency(int hz) {
<> 149:156823d33999 59 lock();
<> 149:156823d33999 60 _hz = hz;
Kojto 169:e3b6fe271b81 61 // If changing format while you are the owner than just
Kojto 169:e3b6fe271b81 62 // update frequency, but if owner is changed than even frequency should be
Kojto 169:e3b6fe271b81 63 // updated which is done by acquire.
Kojto 169:e3b6fe271b81 64 if (_owner == this) {
Kojto 169:e3b6fe271b81 65 spi_frequency(&_spi, _hz);
Kojto 169:e3b6fe271b81 66 } else {
Kojto 169:e3b6fe271b81 67 _acquire();
Kojto 169:e3b6fe271b81 68 }
<> 149:156823d33999 69 unlock();
<> 149:156823d33999 70 }
<> 149:156823d33999 71
<> 149:156823d33999 72 SPI* SPI::_owner = NULL;
<> 149:156823d33999 73 SingletonPtr<PlatformMutex> SPI::_mutex;
<> 149:156823d33999 74
<> 149:156823d33999 75 // ignore the fact there are multiple physical spis, and always update if it wasnt us last
<> 149:156823d33999 76 void SPI::aquire() {
<> 149:156823d33999 77 lock();
<> 149:156823d33999 78 if (_owner != this) {
<> 149:156823d33999 79 spi_format(&_spi, _bits, _mode, 0);
<> 149:156823d33999 80 spi_frequency(&_spi, _hz);
<> 149:156823d33999 81 _owner = this;
<> 149:156823d33999 82 }
<> 149:156823d33999 83 unlock();
<> 149:156823d33999 84 }
<> 149:156823d33999 85
Kojto 169:e3b6fe271b81 86 // Note: Private function with no locking
Kojto 169:e3b6fe271b81 87 void SPI::_acquire() {
Kojto 169:e3b6fe271b81 88 if (_owner != this) {
Kojto 169:e3b6fe271b81 89 spi_format(&_spi, _bits, _mode, 0);
Kojto 169:e3b6fe271b81 90 spi_frequency(&_spi, _hz);
Kojto 169:e3b6fe271b81 91 _owner = this;
Kojto 169:e3b6fe271b81 92 }
Kojto 169:e3b6fe271b81 93 }
Kojto 169:e3b6fe271b81 94
<> 149:156823d33999 95 int SPI::write(int value) {
<> 149:156823d33999 96 lock();
Kojto 169:e3b6fe271b81 97 _acquire();
<> 149:156823d33999 98 int ret = spi_master_write(&_spi, value);
<> 149:156823d33999 99 unlock();
<> 149:156823d33999 100 return ret;
<> 149:156823d33999 101 }
<> 149:156823d33999 102
AnnaBridge 167:e84263d55307 103 int SPI::write(const char *tx_buffer, int tx_length, char *rx_buffer, int rx_length) {
AnnaBridge 167:e84263d55307 104 lock();
Kojto 169:e3b6fe271b81 105 _acquire();
Kojto 170:19eb464bc2be 106 int ret = spi_master_block_write(&_spi, tx_buffer, tx_length, rx_buffer, rx_length, _write_fill);
AnnaBridge 167:e84263d55307 107 unlock();
AnnaBridge 167:e84263d55307 108 return ret;
AnnaBridge 167:e84263d55307 109 }
AnnaBridge 167:e84263d55307 110
<> 149:156823d33999 111 void SPI::lock() {
<> 149:156823d33999 112 _mutex->lock();
<> 149:156823d33999 113 }
<> 149:156823d33999 114
<> 149:156823d33999 115 void SPI::unlock() {
<> 149:156823d33999 116 _mutex->unlock();
<> 149:156823d33999 117 }
<> 149:156823d33999 118
Kojto 170:19eb464bc2be 119 void SPI::set_default_write_value(char data) {
Kojto 170:19eb464bc2be 120 lock();
Kojto 170:19eb464bc2be 121 _write_fill = data;
Kojto 170:19eb464bc2be 122 unlock();
Kojto 170:19eb464bc2be 123 }
Kojto 170:19eb464bc2be 124
<> 149:156823d33999 125 #if DEVICE_SPI_ASYNCH
<> 149:156823d33999 126
<> 149:156823d33999 127 int SPI::transfer(const void *tx_buffer, int tx_length, void *rx_buffer, int rx_length, unsigned char bit_width, const event_callback_t& callback, int event)
<> 149:156823d33999 128 {
<> 149:156823d33999 129 if (spi_active(&_spi)) {
<> 149:156823d33999 130 return queue_transfer(tx_buffer, tx_length, rx_buffer, rx_length, bit_width, callback, event);
<> 149:156823d33999 131 }
<> 149:156823d33999 132 start_transfer(tx_buffer, tx_length, rx_buffer, rx_length, bit_width, callback, event);
<> 149:156823d33999 133 return 0;
<> 149:156823d33999 134 }
<> 149:156823d33999 135
<> 149:156823d33999 136 void SPI::abort_transfer()
<> 149:156823d33999 137 {
<> 149:156823d33999 138 spi_abort_asynch(&_spi);
<> 149:156823d33999 139 #if TRANSACTION_QUEUE_SIZE_SPI
<> 149:156823d33999 140 dequeue_transaction();
<> 149:156823d33999 141 #endif
<> 149:156823d33999 142 }
<> 149:156823d33999 143
<> 149:156823d33999 144
<> 149:156823d33999 145 void SPI::clear_transfer_buffer()
<> 149:156823d33999 146 {
<> 149:156823d33999 147 #if TRANSACTION_QUEUE_SIZE_SPI
<> 149:156823d33999 148 _transaction_buffer.reset();
<> 149:156823d33999 149 #endif
<> 149:156823d33999 150 }
<> 149:156823d33999 151
<> 149:156823d33999 152 void SPI::abort_all_transfers()
<> 149:156823d33999 153 {
<> 149:156823d33999 154 clear_transfer_buffer();
<> 149:156823d33999 155 abort_transfer();
<> 149:156823d33999 156 }
<> 149:156823d33999 157
<> 149:156823d33999 158 int SPI::set_dma_usage(DMAUsage usage)
<> 149:156823d33999 159 {
<> 149:156823d33999 160 if (spi_active(&_spi)) {
<> 149:156823d33999 161 return -1;
<> 149:156823d33999 162 }
<> 149:156823d33999 163 _usage = usage;
<> 149:156823d33999 164 return 0;
<> 149:156823d33999 165 }
<> 149:156823d33999 166
<> 149:156823d33999 167 int SPI::queue_transfer(const void *tx_buffer, int tx_length, void *rx_buffer, int rx_length, unsigned char bit_width, const event_callback_t& callback, int event)
<> 149:156823d33999 168 {
<> 149:156823d33999 169 #if TRANSACTION_QUEUE_SIZE_SPI
<> 149:156823d33999 170 transaction_t t;
<> 149:156823d33999 171
<> 149:156823d33999 172 t.tx_buffer = const_cast<void *>(tx_buffer);
<> 149:156823d33999 173 t.tx_length = tx_length;
<> 149:156823d33999 174 t.rx_buffer = rx_buffer;
<> 149:156823d33999 175 t.rx_length = rx_length;
<> 149:156823d33999 176 t.event = event;
<> 149:156823d33999 177 t.callback = callback;
<> 149:156823d33999 178 t.width = bit_width;
<> 149:156823d33999 179 Transaction<SPI> transaction(this, t);
<> 149:156823d33999 180 if (_transaction_buffer.full()) {
<> 149:156823d33999 181 return -1; // the buffer is full
<> 149:156823d33999 182 } else {
<> 149:156823d33999 183 core_util_critical_section_enter();
<> 149:156823d33999 184 _transaction_buffer.push(transaction);
<> 149:156823d33999 185 if (!spi_active(&_spi)) {
<> 149:156823d33999 186 dequeue_transaction();
<> 149:156823d33999 187 }
<> 149:156823d33999 188 core_util_critical_section_exit();
<> 149:156823d33999 189 return 0;
<> 149:156823d33999 190 }
<> 149:156823d33999 191 #else
<> 149:156823d33999 192 return -1;
<> 149:156823d33999 193 #endif
<> 149:156823d33999 194 }
<> 149:156823d33999 195
<> 149:156823d33999 196 void SPI::start_transfer(const void *tx_buffer, int tx_length, void *rx_buffer, int rx_length, unsigned char bit_width, const event_callback_t& callback, int event)
<> 149:156823d33999 197 {
Kojto 169:e3b6fe271b81 198 _acquire();
<> 149:156823d33999 199 _callback = callback;
<> 149:156823d33999 200 _irq.callback(&SPI::irq_handler_asynch);
<> 149:156823d33999 201 spi_master_transfer(&_spi, tx_buffer, tx_length, rx_buffer, rx_length, bit_width, _irq.entry(), event , _usage);
<> 149:156823d33999 202 }
<> 149:156823d33999 203
<> 149:156823d33999 204 #if TRANSACTION_QUEUE_SIZE_SPI
<> 149:156823d33999 205
<> 149:156823d33999 206 void SPI::start_transaction(transaction_t *data)
<> 149:156823d33999 207 {
<> 149:156823d33999 208 start_transfer(data->tx_buffer, data->tx_length, data->rx_buffer, data->rx_length, data->width, data->callback, data->event);
<> 149:156823d33999 209 }
<> 149:156823d33999 210
<> 149:156823d33999 211 void SPI::dequeue_transaction()
<> 149:156823d33999 212 {
<> 149:156823d33999 213 Transaction<SPI> t;
<> 149:156823d33999 214 if (_transaction_buffer.pop(t)) {
<> 149:156823d33999 215 SPI* obj = t.get_object();
<> 149:156823d33999 216 transaction_t* data = t.get_transaction();
<> 149:156823d33999 217 obj->start_transaction(data);
<> 149:156823d33999 218 }
<> 149:156823d33999 219 }
<> 149:156823d33999 220
<> 149:156823d33999 221 #endif
<> 149:156823d33999 222
<> 149:156823d33999 223 void SPI::irq_handler_asynch(void)
<> 149:156823d33999 224 {
<> 149:156823d33999 225 int event = spi_irq_handler_asynch(&_spi);
<> 149:156823d33999 226 if (_callback && (event & SPI_EVENT_ALL)) {
<> 149:156823d33999 227 _callback.call(event & SPI_EVENT_ALL);
<> 149:156823d33999 228 }
<> 149:156823d33999 229 #if TRANSACTION_QUEUE_SIZE_SPI
<> 149:156823d33999 230 if (event & (SPI_EVENT_ALL | SPI_EVENT_INTERNAL_TRANSFER_COMPLETE)) {
<> 149:156823d33999 231 // SPI peripheral is free (event happend), dequeue transaction
<> 149:156823d33999 232 dequeue_transaction();
<> 149:156823d33999 233 }
<> 149:156823d33999 234 #endif
<> 149:156823d33999 235 }
<> 149:156823d33999 236
<> 149:156823d33999 237 #endif
<> 149:156823d33999 238
<> 149:156823d33999 239 } // namespace mbed
<> 149:156823d33999 240
<> 149:156823d33999 241 #endif