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drivers/SPI.cpp@169:e3b6fe271b81, 2017-07-19 (annotated)

Committer:
Kojto
Date:
Wed Jul 19 17:31:21 2017 +0100
Revision:
169:e3b6fe271b81
Parent:
167:e84263d55307
Child:
170:19eb464bc2be
This updates the lib to the mbed lib v 147

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),
<> 149:156823d33999 35 _hz(1000000) {
<> 149:156823d33999 36 // No lock needed in the constructor
<> 149:156823d33999 37
<> 149:156823d33999 38 spi_init(&_spi, mosi, miso, sclk, ssel);
Kojto 169:e3b6fe271b81 39 _acquire();
<> 149:156823d33999 40 }
<> 149:156823d33999 41
<> 149:156823d33999 42 void SPI::format(int bits, int mode) {
<> 149:156823d33999 43 lock();
<> 149:156823d33999 44 _bits = bits;
<> 149:156823d33999 45 _mode = mode;
Kojto 169:e3b6fe271b81 46 // If changing format while you are the owner than just
Kojto 169:e3b6fe271b81 47 // update format, but if owner is changed than even frequency should be
Kojto 169:e3b6fe271b81 48 // updated which is done by acquire.
Kojto 169:e3b6fe271b81 49 if (_owner == this) {
Kojto 169:e3b6fe271b81 50 spi_format(&_spi, _bits, _mode, 0);
Kojto 169:e3b6fe271b81 51 } else {
Kojto 169:e3b6fe271b81 52 _acquire();
Kojto 169:e3b6fe271b81 53 }
<> 149:156823d33999 54 unlock();
<> 149:156823d33999 55 }
<> 149:156823d33999 56
<> 149:156823d33999 57 void SPI::frequency(int hz) {
<> 149:156823d33999 58 lock();
<> 149:156823d33999 59 _hz = hz;
Kojto 169:e3b6fe271b81 60 // If changing format while you are the owner than just
Kojto 169:e3b6fe271b81 61 // update frequency, but if owner is changed than even frequency should be
Kojto 169:e3b6fe271b81 62 // updated which is done by acquire.
Kojto 169:e3b6fe271b81 63 if (_owner == this) {
Kojto 169:e3b6fe271b81 64 spi_frequency(&_spi, _hz);
Kojto 169:e3b6fe271b81 65 } else {
Kojto 169:e3b6fe271b81 66 _acquire();
Kojto 169:e3b6fe271b81 67 }
<> 149:156823d33999 68 unlock();
<> 149:156823d33999 69 }
<> 149:156823d33999 70
<> 149:156823d33999 71 SPI* SPI::_owner = NULL;
<> 149:156823d33999 72 SingletonPtr<PlatformMutex> SPI::_mutex;
<> 149:156823d33999 73
<> 149:156823d33999 74 // ignore the fact there are multiple physical spis, and always update if it wasnt us last
<> 149:156823d33999 75 void SPI::aquire() {
<> 149:156823d33999 76 lock();
<> 149:156823d33999 77 if (_owner != this) {
<> 149:156823d33999 78 spi_format(&_spi, _bits, _mode, 0);
<> 149:156823d33999 79 spi_frequency(&_spi, _hz);
<> 149:156823d33999 80 _owner = this;
<> 149:156823d33999 81 }
<> 149:156823d33999 82 unlock();
<> 149:156823d33999 83 }
<> 149:156823d33999 84
Kojto 169:e3b6fe271b81 85 // Note: Private function with no locking
Kojto 169:e3b6fe271b81 86 void SPI::_acquire() {
Kojto 169:e3b6fe271b81 87 if (_owner != this) {
Kojto 169:e3b6fe271b81 88 spi_format(&_spi, _bits, _mode, 0);
Kojto 169:e3b6fe271b81 89 spi_frequency(&_spi, _hz);
Kojto 169:e3b6fe271b81 90 _owner = this;
Kojto 169:e3b6fe271b81 91 }
Kojto 169:e3b6fe271b81 92 }
Kojto 169:e3b6fe271b81 93
<> 149:156823d33999 94 int SPI::write(int value) {
<> 149:156823d33999 95 lock();
Kojto 169:e3b6fe271b81 96 _acquire();
<> 149:156823d33999 97 int ret = spi_master_write(&_spi, value);
<> 149:156823d33999 98 unlock();
<> 149:156823d33999 99 return ret;
<> 149:156823d33999 100 }
<> 149:156823d33999 101
AnnaBridge 167:e84263d55307 102 int SPI::write(const char *tx_buffer, int tx_length, char *rx_buffer, int rx_length) {
AnnaBridge 167:e84263d55307 103 lock();
Kojto 169:e3b6fe271b81 104 _acquire();
AnnaBridge 167:e84263d55307 105 int ret = spi_master_block_write(&_spi, tx_buffer, tx_length, rx_buffer, rx_length);
AnnaBridge 167:e84263d55307 106 unlock();
AnnaBridge 167:e84263d55307 107 return ret;
AnnaBridge 167:e84263d55307 108 }
AnnaBridge 167:e84263d55307 109
<> 149:156823d33999 110 void SPI::lock() {
<> 149:156823d33999 111 _mutex->lock();
<> 149:156823d33999 112 }
<> 149:156823d33999 113
<> 149:156823d33999 114 void SPI::unlock() {
<> 149:156823d33999 115 _mutex->unlock();
<> 149:156823d33999 116 }
<> 149:156823d33999 117
<> 149:156823d33999 118 #if DEVICE_SPI_ASYNCH
<> 149:156823d33999 119
<> 149:156823d33999 120 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 121 {
<> 149:156823d33999 122 if (spi_active(&_spi)) {
<> 149:156823d33999 123 return queue_transfer(tx_buffer, tx_length, rx_buffer, rx_length, bit_width, callback, event);
<> 149:156823d33999 124 }
<> 149:156823d33999 125 start_transfer(tx_buffer, tx_length, rx_buffer, rx_length, bit_width, callback, event);
<> 149:156823d33999 126 return 0;
<> 149:156823d33999 127 }
<> 149:156823d33999 128
<> 149:156823d33999 129 void SPI::abort_transfer()
<> 149:156823d33999 130 {
<> 149:156823d33999 131 spi_abort_asynch(&_spi);
<> 149:156823d33999 132 #if TRANSACTION_QUEUE_SIZE_SPI
<> 149:156823d33999 133 dequeue_transaction();
<> 149:156823d33999 134 #endif
<> 149:156823d33999 135 }
<> 149:156823d33999 136
<> 149:156823d33999 137
<> 149:156823d33999 138 void SPI::clear_transfer_buffer()
<> 149:156823d33999 139 {
<> 149:156823d33999 140 #if TRANSACTION_QUEUE_SIZE_SPI
<> 149:156823d33999 141 _transaction_buffer.reset();
<> 149:156823d33999 142 #endif
<> 149:156823d33999 143 }
<> 149:156823d33999 144
<> 149:156823d33999 145 void SPI::abort_all_transfers()
<> 149:156823d33999 146 {
<> 149:156823d33999 147 clear_transfer_buffer();
<> 149:156823d33999 148 abort_transfer();
<> 149:156823d33999 149 }
<> 149:156823d33999 150
<> 149:156823d33999 151 int SPI::set_dma_usage(DMAUsage usage)
<> 149:156823d33999 152 {
<> 149:156823d33999 153 if (spi_active(&_spi)) {
<> 149:156823d33999 154 return -1;
<> 149:156823d33999 155 }
<> 149:156823d33999 156 _usage = usage;
<> 149:156823d33999 157 return 0;
<> 149:156823d33999 158 }
<> 149:156823d33999 159
<> 149:156823d33999 160 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 161 {
<> 149:156823d33999 162 #if TRANSACTION_QUEUE_SIZE_SPI
<> 149:156823d33999 163 transaction_t t;
<> 149:156823d33999 164
<> 149:156823d33999 165 t.tx_buffer = const_cast<void *>(tx_buffer);
<> 149:156823d33999 166 t.tx_length = tx_length;
<> 149:156823d33999 167 t.rx_buffer = rx_buffer;
<> 149:156823d33999 168 t.rx_length = rx_length;
<> 149:156823d33999 169 t.event = event;
<> 149:156823d33999 170 t.callback = callback;
<> 149:156823d33999 171 t.width = bit_width;
<> 149:156823d33999 172 Transaction<SPI> transaction(this, t);
<> 149:156823d33999 173 if (_transaction_buffer.full()) {
<> 149:156823d33999 174 return -1; // the buffer is full
<> 149:156823d33999 175 } else {
<> 149:156823d33999 176 core_util_critical_section_enter();
<> 149:156823d33999 177 _transaction_buffer.push(transaction);
<> 149:156823d33999 178 if (!spi_active(&_spi)) {
<> 149:156823d33999 179 dequeue_transaction();
<> 149:156823d33999 180 }
<> 149:156823d33999 181 core_util_critical_section_exit();
<> 149:156823d33999 182 return 0;
<> 149:156823d33999 183 }
<> 149:156823d33999 184 #else
<> 149:156823d33999 185 return -1;
<> 149:156823d33999 186 #endif
<> 149:156823d33999 187 }
<> 149:156823d33999 188
<> 149:156823d33999 189 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 190 {
Kojto 169:e3b6fe271b81 191 _acquire();
<> 149:156823d33999 192 _callback = callback;
<> 149:156823d33999 193 _irq.callback(&SPI::irq_handler_asynch);
<> 149:156823d33999 194 spi_master_transfer(&_spi, tx_buffer, tx_length, rx_buffer, rx_length, bit_width, _irq.entry(), event , _usage);
<> 149:156823d33999 195 }
<> 149:156823d33999 196
<> 149:156823d33999 197 #if TRANSACTION_QUEUE_SIZE_SPI
<> 149:156823d33999 198
<> 149:156823d33999 199 void SPI::start_transaction(transaction_t *data)
<> 149:156823d33999 200 {
<> 149:156823d33999 201 start_transfer(data->tx_buffer, data->tx_length, data->rx_buffer, data->rx_length, data->width, data->callback, data->event);
<> 149:156823d33999 202 }
<> 149:156823d33999 203
<> 149:156823d33999 204 void SPI::dequeue_transaction()
<> 149:156823d33999 205 {
<> 149:156823d33999 206 Transaction<SPI> t;
<> 149:156823d33999 207 if (_transaction_buffer.pop(t)) {
<> 149:156823d33999 208 SPI* obj = t.get_object();
<> 149:156823d33999 209 transaction_t* data = t.get_transaction();
<> 149:156823d33999 210 obj->start_transaction(data);
<> 149:156823d33999 211 }
<> 149:156823d33999 212 }
<> 149:156823d33999 213
<> 149:156823d33999 214 #endif
<> 149:156823d33999 215
<> 149:156823d33999 216 void SPI::irq_handler_asynch(void)
<> 149:156823d33999 217 {
<> 149:156823d33999 218 int event = spi_irq_handler_asynch(&_spi);
<> 149:156823d33999 219 if (_callback && (event & SPI_EVENT_ALL)) {
<> 149:156823d33999 220 _callback.call(event & SPI_EVENT_ALL);
<> 149:156823d33999 221 }
<> 149:156823d33999 222 #if TRANSACTION_QUEUE_SIZE_SPI
<> 149:156823d33999 223 if (event & (SPI_EVENT_ALL | SPI_EVENT_INTERNAL_TRANSFER_COMPLETE)) {
<> 149:156823d33999 224 // SPI peripheral is free (event happend), dequeue transaction
<> 149:156823d33999 225 dequeue_transaction();
<> 149:156823d33999 226 }
<> 149:156823d33999 227 #endif
<> 149:156823d33999 228 }
<> 149:156823d33999 229
<> 149:156823d33999 230 #endif
<> 149:156823d33999 231
<> 149:156823d33999 232 } // namespace mbed
<> 149:156823d33999 233
<> 149:156823d33999 234 #endif