SerialBase.cpp

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
00003  * SPDX-License-Identifier: Apache-2.0
00004  *
00005  * Licensed under the Apache License, Version 2.0 (the "License");
00006  * you may not use this file except in compliance with the License.
00007  * You may obtain a copy of the License at
00008  *
00009  *     http://www.apache.org/licenses/LICENSE-2.0
00010  *
00011  * Unless required by applicable law or agreed to in writing, software
00012  * distributed under the License is distributed on an "AS IS" BASIS,
00013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00014  * See the License for the specific language governing permissions and
00015  * limitations under the License.
00016  */
00017 #include "drivers/SerialBase.h"
00018 #include "platform/mbed_wait_api.h"
00019 #include "platform/mbed_critical.h"
00020 #include "platform/mbed_power_mgmt.h"
00021 
00022 #if DEVICE_SERIAL
00023 
00024 namespace mbed {
00025 
00026 SerialBase::SerialBase(PinName tx, PinName rx, int baud) :
00027 #if DEVICE_SERIAL_ASYNCH
00028     _thunk_irq(this),
00029 #endif
00030     _baud(baud),
00031     _tx_pin(tx),
00032     _rx_pin(rx),
00033     _init_func(&SerialBase::_init)
00034 {
00035     // No lock needed in the constructor
00036 
00037     for (size_t i = 0; i < sizeof _irq / sizeof _irq[0]; i++) {
00038         _irq[i] = NULL;
00039     }
00040 
00041     (this->*_init_func)();
00042 }
00043 
00044 SerialBase::SerialBase(const serial_pinmap_t &static_pinmap, int baud) :
00045 #if DEVICE_SERIAL_ASYNCH
00046     _thunk_irq(this), _tx_usage(DMA_USAGE_NEVER),
00047     _rx_usage(DMA_USAGE_NEVER), _tx_callback(NULL),
00048     _rx_callback(NULL), _tx_asynch_set(false),
00049     _rx_asynch_set(false),
00050 #endif
00051     _serial(),
00052     _baud(baud),
00053     _tx_pin(static_pinmap.tx_pin),
00054     _rx_pin(static_pinmap.rx_pin),
00055     _static_pinmap(&static_pinmap),
00056     _init_func(&SerialBase::_init_direct)
00057 {
00058     // No lock needed in the constructor
00059 
00060     for (size_t i = 0; i < sizeof _irq / sizeof _irq[0]; i++) {
00061         _irq[i] = NULL;
00062     }
00063 
00064     (this->*_init_func)();
00065 }
00066 
00067 void SerialBase::baud(int baudrate)
00068 {
00069     lock();
00070     serial_baud(&_serial, baudrate);
00071     _baud = baudrate;
00072     unlock();
00073 }
00074 
00075 void SerialBase::format(int bits, Parity parity, int stop_bits)
00076 {
00077     lock();
00078     serial_format(&_serial, bits, (SerialParity)parity, stop_bits);
00079     unlock();
00080 }
00081 
00082 int SerialBase::readable()
00083 {
00084     lock();
00085     int ret = serial_readable(&_serial);
00086     unlock();
00087     return ret;
00088 }
00089 
00090 
00091 int SerialBase::writeable()
00092 {
00093     lock();
00094     int ret = serial_writable(&_serial);
00095     unlock();
00096     return ret;
00097 }
00098 
00099 void SerialBase::attach(Callback<void()> func, IrqType type)
00100 {
00101     lock();
00102     const bool enabled { (_rx_enabled &&(type == RxIrq)) || (_tx_enabled &&(type == TxIrq)) };
00103     // If corresponding direction is not enabled only update the handler
00104     if (!enabled) {
00105         _irq[type] = func;
00106     } else {
00107         // Disable interrupts when attaching interrupt handler
00108         core_util_critical_section_enter();
00109         if (func) {
00110             // lock deep sleep only the first time
00111             if (!_irq[type]) {
00112                 sleep_manager_lock_deep_sleep();
00113             }
00114             _irq[type] = func;
00115             serial_irq_set(&_serial, (SerialIrq)type, 1);
00116         } else {
00117             // unlock deep sleep only the first time
00118             if (_irq[type]) {
00119                 sleep_manager_unlock_deep_sleep();
00120             }
00121             _irq[type] = NULL;
00122             serial_irq_set(&_serial, (SerialIrq)type, 0);
00123         }
00124         core_util_critical_section_exit();
00125     }
00126     unlock();
00127 }
00128 
00129 void SerialBase::_irq_handler(uint32_t id, SerialIrq irq_type)
00130 {
00131     SerialBase *handler = (SerialBase *)id;
00132     if (handler->_irq[irq_type]) {
00133         handler->_irq[irq_type]();
00134     }
00135 }
00136 
00137 int SerialBase::_base_getc()
00138 {
00139     // Mutex is already held
00140     return serial_getc(&_serial);
00141 }
00142 
00143 int SerialBase::_base_putc(int c)
00144 {
00145     // Mutex is already held
00146     serial_putc(&_serial, c);
00147     return c;
00148 }
00149 
00150 void SerialBase::_init()
00151 {
00152     serial_init(&_serial, _tx_pin, _rx_pin);
00153 #if DEVICE_SERIAL_FC
00154     if (_set_flow_control_dp_func) {
00155         (this->*_set_flow_control_dp_func)(_flow_type, _flow1, _flow2);
00156     }
00157 #endif
00158     serial_baud(&_serial, _baud);
00159     serial_irq_handler(&_serial, SerialBase::_irq_handler, (uint32_t)this);
00160 }
00161 
00162 void SerialBase::_init_direct()
00163 {
00164     serial_init_direct(&_serial, _static_pinmap);
00165 #if DEVICE_SERIAL_FC
00166     if (_static_pinmap_fc && _set_flow_control_dp_func) {
00167         (this->*_set_flow_control_sp_func)(_flow_type, *_static_pinmap_fc);
00168     }
00169 #endif
00170     serial_baud(&_serial, _baud);
00171     serial_irq_handler(&_serial, SerialBase::_irq_handler, (uint32_t)this);
00172 }
00173 
00174 void SerialBase::_deinit()
00175 {
00176     serial_free(&_serial);
00177 }
00178 
00179 void SerialBase::enable_input(bool enable)
00180 {
00181     lock();
00182     if (_rx_enabled != enable) {
00183         if (enable && !_tx_enabled) {
00184             (this->*_init_func)();
00185         }
00186 
00187         core_util_critical_section_enter();
00188         if (enable) {
00189             // Enable rx IRQ and lock deep sleep if a rx handler is attached
00190             // (indicated by rx IRQ callback not NULL)
00191             if (_irq[RxIrq]) {
00192                 _irq[RxIrq].call();
00193                 sleep_manager_lock_deep_sleep();
00194                 serial_irq_set(&_serial, (SerialIrq)RxIrq, 1);
00195             }
00196         } else {
00197             // Disable rx IRQ
00198             serial_irq_set(&_serial, (SerialIrq)RxIrq, 0);
00199             // Unlock deep sleep if a rx handler is attached
00200             // (indicated by rx IRQ callback not NULL)
00201             if (_irq[RxIrq]) {
00202                 sleep_manager_unlock_deep_sleep();
00203             }
00204         }
00205         core_util_critical_section_exit();
00206 
00207         _rx_enabled = enable;
00208 
00209         if (!enable && !_tx_enabled) {
00210             _deinit();
00211         }
00212     }
00213     unlock();
00214 }
00215 
00216 void SerialBase::enable_output(bool enable)
00217 {
00218     lock();
00219     if (_tx_enabled != enable) {
00220         if (enable && !_rx_enabled) {
00221             (this->*_init_func)();
00222         }
00223 
00224         core_util_critical_section_enter();
00225         if (enable) {
00226             // Enable tx IRQ and lock deep sleep if a tx handler is attached
00227             // (indicated by tx IRQ callback not NULL)
00228             if (_irq[TxIrq]) {
00229                 _irq[TxIrq].call();
00230                 sleep_manager_lock_deep_sleep();
00231                 serial_irq_set(&_serial, (SerialIrq)TxIrq, 1);
00232             }
00233         } else {
00234             // Disable tx IRQ
00235             serial_irq_set(&_serial, (SerialIrq)TxIrq, 0);
00236             // Unlock deep sleep if a tx handler is attached
00237             // (indicated by tx IRQ callback not NULL)
00238             if (_irq[TxIrq]) {
00239                 sleep_manager_unlock_deep_sleep();
00240             }
00241         }
00242         core_util_critical_section_exit();
00243 
00244         _tx_enabled = enable;
00245 
00246         if (!enable && !_rx_enabled) {
00247             _deinit();
00248         }
00249     }
00250     unlock();
00251 }
00252 
00253 void SerialBase::set_break()
00254 {
00255     lock();
00256     serial_break_set(&_serial);
00257     unlock();
00258 }
00259 
00260 void SerialBase::clear_break()
00261 {
00262     lock();
00263     serial_break_clear(&_serial);
00264     unlock();
00265 }
00266 
00267 void SerialBase::send_break()
00268 {
00269     lock();
00270     // Wait for 1.5 frames before clearing the break condition
00271     // This will have different effects on our platforms, but should
00272     // ensure that we keep the break active for at least one frame.
00273     // We consider a full frame (1 start bit + 8 data bits bits +
00274     // 1 parity bit + 2 stop bits = 12 bits) for computation.
00275     // One bit time (in us) = 1000000/_baud
00276     // Twelve bits: 12000000/baud delay
00277     // 1.5 frames: 18000000/baud delay
00278     serial_break_set(&_serial);
00279     wait_us(18000000 / _baud);
00280     serial_break_clear(&_serial);
00281     unlock();
00282 }
00283 
00284 void SerialBase::lock()
00285 {
00286     // Stub
00287 }
00288 
00289 void SerialBase:: unlock()
00290 {
00291     // Stub
00292 }
00293 
00294 SerialBase::~SerialBase()
00295 {
00296     // No lock needed in destructor
00297 
00298     // Detaching interrupts releases the sleep lock if it was locked
00299     for (int irq = 0; irq < IrqCnt; irq++) {
00300         attach(NULL, (IrqType)irq);
00301     }
00302 }
00303 
00304 #if DEVICE_SERIAL_FC
00305 void SerialBase::set_flow_control(Flow type, PinName flow1, PinName flow2)
00306 {
00307     MBED_ASSERT(_static_pinmap == NULL); // this function must be used when serial object has been created using dynamic pin-map constructor
00308     _set_flow_control_dp_func = &SerialBase::set_flow_control;
00309     lock();
00310 
00311     _flow_type = type;
00312     _flow1 = flow1;
00313     _flow2 = flow2;
00314 
00315     FlowControl flow_type = (FlowControl)type;
00316     switch (type) {
00317         case RTS:
00318             serial_set_flow_control(&_serial, flow_type, flow1, NC);
00319             break;
00320 
00321         case CTS:
00322             serial_set_flow_control(&_serial, flow_type, NC, flow1);
00323             break;
00324 
00325         case RTSCTS:
00326         case Disabled:
00327             serial_set_flow_control(&_serial, flow_type, flow1, flow2);
00328             break;
00329 
00330         default:
00331             break;
00332     }
00333     unlock();
00334 }
00335 
00336 void SerialBase::set_flow_control(Flow type, const serial_fc_pinmap_t &static_pinmap)
00337 {
00338     MBED_ASSERT(_static_pinmap != NULL); // this function must be used when serial object has been created using static pin-map constructor
00339     _set_flow_control_sp_func = &SerialBase::set_flow_control;
00340     lock();
00341     _static_pinmap_fc = &static_pinmap;
00342     _flow_type = type;
00343     FlowControl flow_type = (FlowControl)type;
00344     serial_set_flow_control_direct(&_serial, flow_type, _static_pinmap_fc);
00345     unlock();
00346 }
00347 #endif
00348 
00349 #if DEVICE_SERIAL_ASYNCH
00350 
00351 int SerialBase::write(const uint8_t *buffer, int length, const event_callback_t &callback, int event)
00352 {
00353     int result = 0;
00354     lock();
00355     if (!serial_tx_active(&_serial) && !_tx_asynch_set) {
00356         start_write((void *)buffer, length, 8, callback, event);
00357     } else {
00358         result = -1; // transaction ongoing
00359     }
00360     unlock();
00361     return result;
00362 }
00363 
00364 int SerialBase::write(const uint16_t *buffer, int length, const event_callback_t &callback, int event)
00365 {
00366     int result = 0;
00367     lock();
00368     if (!serial_tx_active(&_serial) && !_tx_asynch_set) {
00369         start_write((void *)buffer, length, 16, callback, event);
00370     } else {
00371         result = -1; // transaction ongoing
00372     }
00373     unlock();
00374     return result;
00375 }
00376 
00377 void SerialBase::start_write(const void *buffer, int buffer_size, char buffer_width, const event_callback_t &callback, int event)
00378 {
00379     _tx_asynch_set = true;
00380     _tx_callback = callback;
00381 
00382     _thunk_irq.callback(&SerialBase::interrupt_handler_asynch);
00383     sleep_manager_lock_deep_sleep();
00384     serial_tx_asynch(&_serial, buffer, buffer_size, buffer_width, _thunk_irq.entry(), event, _tx_usage);
00385 }
00386 
00387 void SerialBase::abort_write(void)
00388 {
00389     lock();
00390     core_util_critical_section_enter();
00391     if (_tx_asynch_set) {
00392         _tx_callback = NULL;
00393         _tx_asynch_set = false;
00394         serial_tx_abort_asynch(&_serial);
00395         sleep_manager_unlock_deep_sleep();
00396     }
00397     core_util_critical_section_exit();
00398     unlock();
00399 }
00400 
00401 void SerialBase::abort_read(void)
00402 {
00403     lock();
00404     core_util_critical_section_enter();
00405     if (_rx_asynch_set) {
00406         _rx_callback = NULL;
00407         _rx_asynch_set = false;
00408         serial_rx_abort_asynch(&_serial);
00409         sleep_manager_unlock_deep_sleep();
00410     }
00411     core_util_critical_section_exit();
00412     unlock();
00413 }
00414 
00415 int SerialBase::set_dma_usage_tx(DMAUsage usage)
00416 {
00417     if (serial_tx_active(&_serial)) {
00418         return -1;
00419     }
00420     _tx_usage = usage;
00421     return 0;
00422 }
00423 
00424 int SerialBase::set_dma_usage_rx(DMAUsage usage)
00425 {
00426     if (serial_tx_active(&_serial)) {
00427         return -1;
00428     }
00429     _rx_usage = usage;
00430     return 0;
00431 }
00432 
00433 int SerialBase::read(uint8_t *buffer, int length, const event_callback_t &callback, int event, unsigned char char_match)
00434 {
00435     int result = 0;
00436     lock();
00437     if (!serial_rx_active(&_serial) && !_rx_asynch_set) {
00438         start_read((void *)buffer, length, 8, callback, event, char_match);
00439     } else {
00440         result = -1; // transaction ongoing
00441     }
00442     unlock();
00443     return result;
00444 }
00445 
00446 
00447 int SerialBase::read(uint16_t *buffer, int length, const event_callback_t &callback, int event, unsigned char char_match)
00448 {
00449     int result = 0;
00450     lock();
00451     if (!serial_rx_active(&_serial) && !_rx_asynch_set) {
00452         start_read((void *)buffer, length, 16, callback, event, char_match);
00453     } else {
00454         result = -1; // transaction ongoing
00455     }
00456     unlock();
00457     return result;
00458 }
00459 
00460 
00461 void SerialBase::start_read(void *buffer, int buffer_size, char buffer_width, const event_callback_t &callback, int event, unsigned char char_match)
00462 {
00463     _rx_asynch_set = true;
00464     _rx_callback = callback;
00465     _thunk_irq.callback(&SerialBase::interrupt_handler_asynch);
00466     sleep_manager_lock_deep_sleep();
00467     serial_rx_asynch(&_serial, buffer, buffer_size, buffer_width, _thunk_irq.entry(), event, char_match, _rx_usage);
00468 }
00469 
00470 void SerialBase::interrupt_handler_asynch(void)
00471 {
00472     int event = serial_irq_handler_asynch(&_serial);
00473     int rx_event = event & SERIAL_EVENT_RX_MASK;
00474 
00475     if (_rx_asynch_set && rx_event) {
00476         event_callback_t cb = _rx_callback;
00477         _rx_asynch_set = false;
00478         _rx_callback = NULL;
00479         if (cb) {
00480             cb.call(rx_event);
00481         }
00482         sleep_manager_unlock_deep_sleep();
00483     }
00484 
00485     int tx_event = event & SERIAL_EVENT_TX_MASK;
00486     if (_tx_asynch_set && tx_event) {
00487         event_callback_t cb = _tx_callback;
00488         _tx_asynch_set = false;
00489         _tx_callback = NULL;
00490         if (cb) {
00491             cb.call(tx_event);
00492         }
00493         sleep_manager_unlock_deep_sleep();
00494     }
00495 }
00496 
00497 #endif
00498 
00499 } // namespace mbed
00500 
00501 #endif