John Karatka / mbed

mbed

Fork of mbed-dev by mbed official

drivers/UARTSerial.cpp@181:96ed750bd169, 2018-01-17 (annotated)

Committer:
Anna Bridge
Date:
Wed Jan 17 15:23:54 2018 +0000
Revision:
181:96ed750bd169
Parent:
177:447f873cad2f 
mbed-dev libray. Release version 158

Who changed what in which revision?

UserRevisionLine numberNew contents of line
AnnaBridge 167:e84263d55307 1 /* mbed Microcontroller Library
AnnaBridge 167:e84263d55307 2 * Copyright (c) 2006-2017 ARM Limited
AnnaBridge 167:e84263d55307 3 *
AnnaBridge 167:e84263d55307 4 * Licensed under the Apache License, Version 2.0 (the "License");
AnnaBridge 167:e84263d55307 5 * you may not use this file except in compliance with the License.
AnnaBridge 167:e84263d55307 6 * You may obtain a copy of the License at
AnnaBridge 167:e84263d55307 7 *
AnnaBridge 167:e84263d55307 8 * http://www.apache.org/licenses/LICENSE-2.0
AnnaBridge 167:e84263d55307 9 *
AnnaBridge 167:e84263d55307 10 * Unless required by applicable law or agreed to in writing, software
AnnaBridge 167:e84263d55307 11 * distributed under the License is distributed on an "AS IS" BASIS,
AnnaBridge 167:e84263d55307 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
AnnaBridge 167:e84263d55307 13 * See the License for the specific language governing permissions and
AnnaBridge 167:e84263d55307 14 * limitations under the License.
AnnaBridge 167:e84263d55307 15 */
AnnaBridge 167:e84263d55307 16
AnnaBridge 168:9672193075cf 17 #if (DEVICE_SERIAL && DEVICE_INTERRUPTIN)
AnnaBridge 167:e84263d55307 18
AnnaBridge 167:e84263d55307 19 #include <errno.h>
AnnaBridge 167:e84263d55307 20 #include "UARTSerial.h"
AnnaBridge 167:e84263d55307 21 #include "platform/mbed_poll.h"
AnnaBridge 177:447f873cad2f 22
AnnaBridge 177:447f873cad2f 23 #if MBED_CONF_RTOS_PRESENT
AnnaBridge 177:447f873cad2f 24 #include "rtos/Thread.h"
AnnaBridge 177:447f873cad2f 25 #else
AnnaBridge 167:e84263d55307 26 #include "platform/mbed_wait_api.h"
AnnaBridge 177:447f873cad2f 27 #endif
AnnaBridge 167:e84263d55307 28
AnnaBridge 167:e84263d55307 29 namespace mbed {
AnnaBridge 167:e84263d55307 30
AnnaBridge 167:e84263d55307 31 UARTSerial::UARTSerial(PinName tx, PinName rx, int baud) :
AnnaBridge 167:e84263d55307 32 SerialBase(tx, rx, baud),
AnnaBridge 167:e84263d55307 33 _blocking(true),
AnnaBridge 167:e84263d55307 34 _tx_irq_enabled(false),
Anna Bridge 181:96ed750bd169 35 _rx_irq_enabled(true),
AnnaBridge 167:e84263d55307 36 _dcd_irq(NULL)
AnnaBridge 167:e84263d55307 37 {
AnnaBridge 167:e84263d55307 38 /* Attatch IRQ routines to the serial device. */
AnnaBridge 167:e84263d55307 39 SerialBase::attach(callback(this, &UARTSerial::rx_irq), RxIrq);
AnnaBridge 167:e84263d55307 40 }
AnnaBridge 167:e84263d55307 41
AnnaBridge 167:e84263d55307 42 UARTSerial::~UARTSerial()
AnnaBridge 167:e84263d55307 43 {
AnnaBridge 167:e84263d55307 44 delete _dcd_irq;
AnnaBridge 167:e84263d55307 45 }
AnnaBridge 167:e84263d55307 46
AnnaBridge 167:e84263d55307 47 void UARTSerial::dcd_irq()
AnnaBridge 167:e84263d55307 48 {
AnnaBridge 167:e84263d55307 49 wake();
AnnaBridge 167:e84263d55307 50 }
AnnaBridge 167:e84263d55307 51
Kojto 171:19eb464bc2be 52 void UARTSerial::set_baud(int baud)
Kojto 171:19eb464bc2be 53 {
Kojto 171:19eb464bc2be 54 SerialBase::baud(baud);
Kojto 171:19eb464bc2be 55 }
Kojto 171:19eb464bc2be 56
AnnaBridge 167:e84263d55307 57 void UARTSerial::set_data_carrier_detect(PinName dcd_pin, bool active_high)
AnnaBridge 167:e84263d55307 58 {
AnnaBridge 167:e84263d55307 59 delete _dcd_irq;
AnnaBridge 167:e84263d55307 60 _dcd_irq = NULL;
AnnaBridge 167:e84263d55307 61
AnnaBridge 167:e84263d55307 62 if (dcd_pin != NC) {
AnnaBridge 167:e84263d55307 63 _dcd_irq = new InterruptIn(dcd_pin);
AnnaBridge 167:e84263d55307 64 if (active_high) {
AnnaBridge 167:e84263d55307 65 _dcd_irq->fall(callback(this, &UARTSerial::dcd_irq));
AnnaBridge 167:e84263d55307 66 } else {
AnnaBridge 167:e84263d55307 67 _dcd_irq->rise(callback(this, &UARTSerial::dcd_irq));
AnnaBridge 167:e84263d55307 68 }
AnnaBridge 167:e84263d55307 69 }
AnnaBridge 167:e84263d55307 70 }
AnnaBridge 167:e84263d55307 71
Anna Bridge 181:96ed750bd169 72 void UARTSerial::set_format(int bits, Parity parity, int stop_bits)
Anna Bridge 181:96ed750bd169 73 {
Anna Bridge 181:96ed750bd169 74 api_lock();
Anna Bridge 181:96ed750bd169 75 SerialBase::format(bits, parity, stop_bits);
Anna Bridge 181:96ed750bd169 76 api_unlock();
Anna Bridge 181:96ed750bd169 77 }
Anna Bridge 181:96ed750bd169 78
Anna Bridge 181:96ed750bd169 79 #if DEVICE_SERIAL_FC
Anna Bridge 181:96ed750bd169 80 void UARTSerial::set_flow_control(Flow type, PinName flow1, PinName flow2)
Anna Bridge 181:96ed750bd169 81 {
Anna Bridge 181:96ed750bd169 82 api_lock();
Anna Bridge 181:96ed750bd169 83 SerialBase::set_flow_control(type, flow1, flow2);
Anna Bridge 181:96ed750bd169 84 api_unlock();
Anna Bridge 181:96ed750bd169 85 }
Anna Bridge 181:96ed750bd169 86 #endif
Anna Bridge 181:96ed750bd169 87
AnnaBridge 167:e84263d55307 88 int UARTSerial::close()
AnnaBridge 167:e84263d55307 89 {
AnnaBridge 167:e84263d55307 90 /* Does not let us pass a file descriptor. So how to close ?
AnnaBridge 167:e84263d55307 91 * Also, does it make sense to close a device type file descriptor*/
AnnaBridge 167:e84263d55307 92 return 0;
AnnaBridge 167:e84263d55307 93 }
AnnaBridge 167:e84263d55307 94
AnnaBridge 167:e84263d55307 95 int UARTSerial::isatty()
AnnaBridge 167:e84263d55307 96 {
AnnaBridge 167:e84263d55307 97 return 1;
AnnaBridge 167:e84263d55307 98
AnnaBridge 167:e84263d55307 99 }
AnnaBridge 167:e84263d55307 100
AnnaBridge 167:e84263d55307 101 off_t UARTSerial::seek(off_t offset, int whence)
AnnaBridge 167:e84263d55307 102 {
AnnaBridge 167:e84263d55307 103 /*XXX lseek can be done theoratically, but is it sane to mark positions on a dynamically growing/shrinking
AnnaBridge 167:e84263d55307 104 * buffer system (from an interrupt context) */
AnnaBridge 167:e84263d55307 105 return -ESPIPE;
AnnaBridge 167:e84263d55307 106 }
AnnaBridge 167:e84263d55307 107
AnnaBridge 167:e84263d55307 108 int UARTSerial::sync()
AnnaBridge 167:e84263d55307 109 {
AnnaBridge 168:9672193075cf 110 api_lock();
AnnaBridge 167:e84263d55307 111
AnnaBridge 167:e84263d55307 112 while (!_txbuf.empty()) {
AnnaBridge 168:9672193075cf 113 api_unlock();
AnnaBridge 167:e84263d55307 114 // Doing better than wait would require TxIRQ to also do wake() when becoming empty. Worth it?
AnnaBridge 167:e84263d55307 115 wait_ms(1);
AnnaBridge 168:9672193075cf 116 api_lock();
AnnaBridge 167:e84263d55307 117 }
AnnaBridge 167:e84263d55307 118
AnnaBridge 168:9672193075cf 119 api_unlock();
AnnaBridge 167:e84263d55307 120
AnnaBridge 167:e84263d55307 121 return 0;
AnnaBridge 167:e84263d55307 122 }
AnnaBridge 167:e84263d55307 123
AnnaBridge 167:e84263d55307 124 void UARTSerial::sigio(Callback<void()> func) {
AnnaBridge 167:e84263d55307 125 core_util_critical_section_enter();
AnnaBridge 167:e84263d55307 126 _sigio_cb = func;
AnnaBridge 167:e84263d55307 127 if (_sigio_cb) {
AnnaBridge 167:e84263d55307 128 short current_events = poll(0x7FFF);
AnnaBridge 167:e84263d55307 129 if (current_events) {
AnnaBridge 167:e84263d55307 130 _sigio_cb();
AnnaBridge 167:e84263d55307 131 }
AnnaBridge 167:e84263d55307 132 }
AnnaBridge 167:e84263d55307 133 core_util_critical_section_exit();
AnnaBridge 167:e84263d55307 134 }
AnnaBridge 167:e84263d55307 135
AnnaBridge 167:e84263d55307 136 ssize_t UARTSerial::write(const void* buffer, size_t length)
AnnaBridge 167:e84263d55307 137 {
AnnaBridge 167:e84263d55307 138 size_t data_written = 0;
AnnaBridge 167:e84263d55307 139 const char *buf_ptr = static_cast<const char *>(buffer);
AnnaBridge 167:e84263d55307 140
Anna Bridge 181:96ed750bd169 141 if (length == 0) {
Anna Bridge 181:96ed750bd169 142 return 0;
AnnaBridge 167:e84263d55307 143 }
AnnaBridge 167:e84263d55307 144
Anna Bridge 181:96ed750bd169 145 api_lock();
Anna Bridge 181:96ed750bd169 146
Anna Bridge 181:96ed750bd169 147 // Unlike read, we should write the whole thing if blocking. POSIX only
Anna Bridge 181:96ed750bd169 148 // allows partial as a side-effect of signal handling; it normally tries to
Anna Bridge 181:96ed750bd169 149 // write everything if blocking. Without signals we can always write all.
Anna Bridge 181:96ed750bd169 150 while (data_written < length) {
AnnaBridge 167:e84263d55307 151
Anna Bridge 181:96ed750bd169 152 if (_txbuf.full()) {
Anna Bridge 181:96ed750bd169 153 if (!_blocking) {
Anna Bridge 181:96ed750bd169 154 break;
Anna Bridge 181:96ed750bd169 155 }
Anna Bridge 181:96ed750bd169 156 do {
Anna Bridge 181:96ed750bd169 157 api_unlock();
Anna Bridge 181:96ed750bd169 158 wait_ms(1); // XXX todo - proper wait, WFE for non-rtos ?
Anna Bridge 181:96ed750bd169 159 api_lock();
Anna Bridge 181:96ed750bd169 160 } while (_txbuf.full());
AnnaBridge 167:e84263d55307 161 }
Anna Bridge 181:96ed750bd169 162
Anna Bridge 181:96ed750bd169 163 while (data_written < length && !_txbuf.full()) {
Anna Bridge 181:96ed750bd169 164 _txbuf.push(*buf_ptr++);
Anna Bridge 181:96ed750bd169 165 data_written++;
Anna Bridge 181:96ed750bd169 166 }
Anna Bridge 181:96ed750bd169 167
Anna Bridge 181:96ed750bd169 168 core_util_critical_section_enter();
Anna Bridge 181:96ed750bd169 169 if (!_tx_irq_enabled) {
Anna Bridge 181:96ed750bd169 170 UARTSerial::tx_irq(); // only write to hardware in one place
Anna Bridge 181:96ed750bd169 171 if (!_txbuf.empty()) {
Anna Bridge 181:96ed750bd169 172 SerialBase::attach(callback(this, &UARTSerial::tx_irq), TxIrq);
Anna Bridge 181:96ed750bd169 173 _tx_irq_enabled = true;
Anna Bridge 181:96ed750bd169 174 }
Anna Bridge 181:96ed750bd169 175 }
Anna Bridge 181:96ed750bd169 176 core_util_critical_section_exit();
AnnaBridge 167:e84263d55307 177 }
AnnaBridge 167:e84263d55307 178
AnnaBridge 168:9672193075cf 179 api_unlock();
AnnaBridge 167:e84263d55307 180
Anna Bridge 181:96ed750bd169 181 return data_written != 0 ? (ssize_t) data_written : (ssize_t) -EAGAIN;
AnnaBridge 167:e84263d55307 182 }
AnnaBridge 167:e84263d55307 183
AnnaBridge 167:e84263d55307 184 ssize_t UARTSerial::read(void* buffer, size_t length)
AnnaBridge 167:e84263d55307 185 {
AnnaBridge 167:e84263d55307 186 size_t data_read = 0;
AnnaBridge 167:e84263d55307 187
AnnaBridge 167:e84263d55307 188 char *ptr = static_cast<char *>(buffer);
AnnaBridge 167:e84263d55307 189
Anna Bridge 181:96ed750bd169 190 if (length == 0) {
Anna Bridge 181:96ed750bd169 191 return 0;
Anna Bridge 181:96ed750bd169 192 }
Anna Bridge 181:96ed750bd169 193
AnnaBridge 168:9672193075cf 194 api_lock();
AnnaBridge 167:e84263d55307 195
AnnaBridge 167:e84263d55307 196 while (_rxbuf.empty()) {
AnnaBridge 167:e84263d55307 197 if (!_blocking) {
AnnaBridge 168:9672193075cf 198 api_unlock();
AnnaBridge 167:e84263d55307 199 return -EAGAIN;
AnnaBridge 167:e84263d55307 200 }
AnnaBridge 168:9672193075cf 201 api_unlock();
AnnaBridge 167:e84263d55307 202 wait_ms(1); // XXX todo - proper wait, WFE for non-rtos ?
AnnaBridge 168:9672193075cf 203 api_lock();
AnnaBridge 167:e84263d55307 204 }
AnnaBridge 167:e84263d55307 205
AnnaBridge 167:e84263d55307 206 while (data_read < length && !_rxbuf.empty()) {
AnnaBridge 167:e84263d55307 207 _rxbuf.pop(*ptr++);
AnnaBridge 167:e84263d55307 208 data_read++;
AnnaBridge 167:e84263d55307 209 }
AnnaBridge 167:e84263d55307 210
Anna Bridge 181:96ed750bd169 211 core_util_critical_section_enter();
Anna Bridge 181:96ed750bd169 212 if (!_rx_irq_enabled) {
Anna Bridge 181:96ed750bd169 213 UARTSerial::rx_irq(); // only read from hardware in one place
Anna Bridge 181:96ed750bd169 214 if (!_rxbuf.full()) {
Anna Bridge 181:96ed750bd169 215 SerialBase::attach(callback(this, &UARTSerial::rx_irq), RxIrq);
Anna Bridge 181:96ed750bd169 216 _rx_irq_enabled = true;
Anna Bridge 181:96ed750bd169 217 }
Anna Bridge 181:96ed750bd169 218 }
Anna Bridge 181:96ed750bd169 219 core_util_critical_section_exit();
Anna Bridge 181:96ed750bd169 220
AnnaBridge 168:9672193075cf 221 api_unlock();
AnnaBridge 167:e84263d55307 222
AnnaBridge 167:e84263d55307 223 return data_read;
AnnaBridge 167:e84263d55307 224 }
AnnaBridge 167:e84263d55307 225
AnnaBridge 167:e84263d55307 226 bool UARTSerial::hup() const
AnnaBridge 167:e84263d55307 227 {
AnnaBridge 167:e84263d55307 228 return _dcd_irq && _dcd_irq->read() != 0;
AnnaBridge 167:e84263d55307 229 }
AnnaBridge 167:e84263d55307 230
AnnaBridge 167:e84263d55307 231 void UARTSerial::wake()
AnnaBridge 167:e84263d55307 232 {
AnnaBridge 167:e84263d55307 233 if (_sigio_cb) {
AnnaBridge 167:e84263d55307 234 _sigio_cb();
AnnaBridge 167:e84263d55307 235 }
AnnaBridge 167:e84263d55307 236 }
AnnaBridge 167:e84263d55307 237
AnnaBridge 167:e84263d55307 238 short UARTSerial::poll(short events) const {
AnnaBridge 167:e84263d55307 239
AnnaBridge 167:e84263d55307 240 short revents = 0;
AnnaBridge 167:e84263d55307 241 /* Check the Circular Buffer if space available for writing out */
AnnaBridge 167:e84263d55307 242
AnnaBridge 167:e84263d55307 243
AnnaBridge 167:e84263d55307 244 if (!_rxbuf.empty()) {
AnnaBridge 167:e84263d55307 245 revents |= POLLIN;
AnnaBridge 167:e84263d55307 246 }
AnnaBridge 167:e84263d55307 247
AnnaBridge 167:e84263d55307 248 /* POLLHUP and POLLOUT are mutually exclusive */
AnnaBridge 167:e84263d55307 249 if (hup()) {
AnnaBridge 167:e84263d55307 250 revents |= POLLHUP;
AnnaBridge 167:e84263d55307 251 } else if (!_txbuf.full()) {
AnnaBridge 167:e84263d55307 252 revents |= POLLOUT;
AnnaBridge 167:e84263d55307 253 }
AnnaBridge 167:e84263d55307 254
AnnaBridge 167:e84263d55307 255 /*TODO Handle other event types */
AnnaBridge 167:e84263d55307 256
AnnaBridge 167:e84263d55307 257 return revents;
AnnaBridge 167:e84263d55307 258 }
AnnaBridge 167:e84263d55307 259
AnnaBridge 168:9672193075cf 260 void UARTSerial::lock()
AnnaBridge 168:9672193075cf 261 {
AnnaBridge 168:9672193075cf 262 // This is the override for SerialBase.
AnnaBridge 168:9672193075cf 263 // No lock required as we only use SerialBase from interrupt or from
AnnaBridge 168:9672193075cf 264 // inside our own critical section.
AnnaBridge 168:9672193075cf 265 }
AnnaBridge 168:9672193075cf 266
AnnaBridge 168:9672193075cf 267 void UARTSerial::unlock()
AnnaBridge 168:9672193075cf 268 {
AnnaBridge 168:9672193075cf 269 // This is the override for SerialBase.
AnnaBridge 168:9672193075cf 270 }
AnnaBridge 168:9672193075cf 271
AnnaBridge 168:9672193075cf 272 void UARTSerial::api_lock(void)
AnnaBridge 167:e84263d55307 273 {
AnnaBridge 167:e84263d55307 274 _mutex.lock();
AnnaBridge 167:e84263d55307 275 }
AnnaBridge 167:e84263d55307 276
AnnaBridge 168:9672193075cf 277 void UARTSerial::api_unlock(void)
AnnaBridge 167:e84263d55307 278 {
AnnaBridge 167:e84263d55307 279 _mutex.unlock();
AnnaBridge 167:e84263d55307 280 }
AnnaBridge 167:e84263d55307 281
AnnaBridge 167:e84263d55307 282 void UARTSerial::rx_irq(void)
AnnaBridge 167:e84263d55307 283 {
AnnaBridge 167:e84263d55307 284 bool was_empty = _rxbuf.empty();
AnnaBridge 167:e84263d55307 285
AnnaBridge 167:e84263d55307 286 /* Fill in the receive buffer if the peripheral is readable
AnnaBridge 167:e84263d55307 287 * and receive buffer is not full. */
Anna Bridge 181:96ed750bd169 288 while (!_rxbuf.full() && SerialBase::readable()) {
AnnaBridge 167:e84263d55307 289 char data = SerialBase::_base_getc();
Anna Bridge 181:96ed750bd169 290 _rxbuf.push(data);
Anna Bridge 181:96ed750bd169 291 }
Anna Bridge 181:96ed750bd169 292
Anna Bridge 181:96ed750bd169 293 if (_rx_irq_enabled && _rxbuf.full()) {
Anna Bridge 181:96ed750bd169 294 SerialBase::attach(NULL, RxIrq);
Anna Bridge 181:96ed750bd169 295 _rx_irq_enabled = false;
AnnaBridge 167:e84263d55307 296 }
AnnaBridge 167:e84263d55307 297
AnnaBridge 167:e84263d55307 298 /* Report the File handler that data is ready to be read from the buffer. */
AnnaBridge 167:e84263d55307 299 if (was_empty && !_rxbuf.empty()) {
AnnaBridge 167:e84263d55307 300 wake();
AnnaBridge 167:e84263d55307 301 }
AnnaBridge 167:e84263d55307 302 }
AnnaBridge 167:e84263d55307 303
AnnaBridge 167:e84263d55307 304 // Also called from write to start transfer
AnnaBridge 167:e84263d55307 305 void UARTSerial::tx_irq(void)
AnnaBridge 167:e84263d55307 306 {
AnnaBridge 167:e84263d55307 307 bool was_full = _txbuf.full();
AnnaBridge 167:e84263d55307 308
AnnaBridge 167:e84263d55307 309 /* Write to the peripheral if there is something to write
AnnaBridge 167:e84263d55307 310 * and if the peripheral is available to write. */
AnnaBridge 167:e84263d55307 311 while (!_txbuf.empty() && SerialBase::writeable()) {
AnnaBridge 167:e84263d55307 312 char data;
AnnaBridge 167:e84263d55307 313 _txbuf.pop(data);
AnnaBridge 167:e84263d55307 314 SerialBase::_base_putc(data);
AnnaBridge 167:e84263d55307 315 }
AnnaBridge 167:e84263d55307 316
AnnaBridge 167:e84263d55307 317 if (_tx_irq_enabled && _txbuf.empty()) {
AnnaBridge 167:e84263d55307 318 SerialBase::attach(NULL, TxIrq);
AnnaBridge 167:e84263d55307 319 _tx_irq_enabled = false;
AnnaBridge 167:e84263d55307 320 }
AnnaBridge 167:e84263d55307 321
AnnaBridge 167:e84263d55307 322 /* Report the File handler that data can be written to peripheral. */
AnnaBridge 167:e84263d55307 323 if (was_full && !_txbuf.full() && !hup()) {
AnnaBridge 167:e84263d55307 324 wake();
AnnaBridge 167:e84263d55307 325 }
AnnaBridge 167:e84263d55307 326 }
AnnaBridge 167:e84263d55307 327
AnnaBridge 177:447f873cad2f 328 void UARTSerial::wait_ms(uint32_t millisec)
AnnaBridge 177:447f873cad2f 329 {
AnnaBridge 177:447f873cad2f 330 /* wait_ms implementation for RTOS spins until exact microseconds - we
AnnaBridge 177:447f873cad2f 331 * want to just sleep until next tick.
AnnaBridge 177:447f873cad2f 332 */
AnnaBridge 177:447f873cad2f 333 #if MBED_CONF_RTOS_PRESENT
AnnaBridge 177:447f873cad2f 334 rtos::Thread::wait(millisec);
AnnaBridge 177:447f873cad2f 335 #else
AnnaBridge 177:447f873cad2f 336 ::wait_ms(millisec);
AnnaBridge 177:447f873cad2f 337 #endif
AnnaBridge 177:447f873cad2f 338 }
AnnaBridge 167:e84263d55307 339 } //namespace mbed
AnnaBridge 167:e84263d55307 340
AnnaBridge 168:9672193075cf 341 #endif //(DEVICE_SERIAL && DEVICE_INTERRUPTIN)