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Diff: drivers/SerialBase.cpp
- Revision:
- 149:156823d33999
- Child:
- 160:d5399cc887bb
diff -r 21d94c44109e -r 156823d33999 drivers/SerialBase.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/drivers/SerialBase.cpp Fri Oct 28 11:17:30 2016 +0100 @@ -0,0 +1,252 @@ +/* mbed Microcontroller Library + * Copyright (c) 2006-2013 ARM Limited + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +#include "drivers/SerialBase.h" +#include "platform/wait_api.h" +#include "platform/critical.h" + +#if DEVICE_SERIAL + +namespace mbed { + +static void donothing() {}; + +SerialBase::SerialBase(PinName tx, PinName rx, int baud) : +#if DEVICE_SERIAL_ASYNCH + _thunk_irq(this), _tx_usage(DMA_USAGE_NEVER), + _rx_usage(DMA_USAGE_NEVER), +#endif + _serial(), _baud(baud) { + // No lock needed in the constructor + + for (size_t i = 0; i < sizeof _irq / sizeof _irq[0]; i++) { + _irq[i].attach(donothing); + } + + serial_init(&_serial, tx, rx); + serial_baud(&_serial, _baud); + serial_irq_handler(&_serial, SerialBase::_irq_handler, (uint32_t)this); +} + +void SerialBase::baud(int baudrate) { + lock(); + serial_baud(&_serial, baudrate); + _baud = baudrate; + unlock(); +} + +void SerialBase::format(int bits, Parity parity, int stop_bits) { + lock(); + serial_format(&_serial, bits, (SerialParity)parity, stop_bits); + unlock(); +} + +int SerialBase::readable() { + lock(); + int ret = serial_readable(&_serial); + unlock(); + return ret; +} + + +int SerialBase::writeable() { + lock(); + int ret = serial_writable(&_serial); + unlock(); + return ret; +} + +void SerialBase::attach(Callback<void()> func, IrqType type) { + lock(); + // Disable interrupts when attaching interrupt handler + core_util_critical_section_enter(); + if (func) { + _irq[type].attach(func); + serial_irq_set(&_serial, (SerialIrq)type, 1); + } else { + _irq[type].attach(donothing); + serial_irq_set(&_serial, (SerialIrq)type, 0); + } + core_util_critical_section_exit(); + unlock(); +} + +void SerialBase::_irq_handler(uint32_t id, SerialIrq irq_type) { + SerialBase *handler = (SerialBase*)id; + handler->_irq[irq_type].call(); +} + +int SerialBase::_base_getc() { + // Mutex is already held + return serial_getc(&_serial); +} + +int SerialBase::_base_putc(int c) { + // Mutex is already held + serial_putc(&_serial, c); + return c; +} + +void SerialBase::send_break() { + lock(); + // Wait for 1.5 frames before clearing the break condition + // This will have different effects on our platforms, but should + // ensure that we keep the break active for at least one frame. + // We consider a full frame (1 start bit + 8 data bits bits + + // 1 parity bit + 2 stop bits = 12 bits) for computation. + // One bit time (in us) = 1000000/_baud + // Twelve bits: 12000000/baud delay + // 1.5 frames: 18000000/baud delay + serial_break_set(&_serial); + wait_us(18000000/_baud); + serial_break_clear(&_serial); + unlock(); +} + +void SerialBase::lock() { + // Stub +} + +void SerialBase:: unlock() { + // Stub +} + +#if DEVICE_SERIAL_FC +void SerialBase::set_flow_control(Flow type, PinName flow1, PinName flow2) { + lock(); + FlowControl flow_type = (FlowControl)type; + switch(type) { + case RTS: + serial_set_flow_control(&_serial, flow_type, flow1, NC); + break; + + case CTS: + serial_set_flow_control(&_serial, flow_type, NC, flow1); + break; + + case RTSCTS: + case Disabled: + serial_set_flow_control(&_serial, flow_type, flow1, flow2); + break; + + default: + break; + } + unlock(); +} +#endif + +#if DEVICE_SERIAL_ASYNCH + +int SerialBase::write(const uint8_t *buffer, int length, const event_callback_t& callback, int event) +{ + if (serial_tx_active(&_serial)) { + return -1; // transaction ongoing + } + start_write((void *)buffer, length, 8, callback, event); + return 0; +} + +int SerialBase::write(const uint16_t *buffer, int length, const event_callback_t& callback, int event) +{ + if (serial_tx_active(&_serial)) { + return -1; // transaction ongoing + } + start_write((void *)buffer, length, 16, callback, event); + return 0; +} + +void SerialBase::start_write(const void *buffer, int buffer_size, char buffer_width, const event_callback_t& callback, int event) +{ + _tx_callback = callback; + + _thunk_irq.callback(&SerialBase::interrupt_handler_asynch); + serial_tx_asynch(&_serial, buffer, buffer_size, buffer_width, _thunk_irq.entry(), event, _tx_usage); +} + +void SerialBase::abort_write(void) +{ + serial_tx_abort_asynch(&_serial); +} + +void SerialBase::abort_read(void) +{ + serial_rx_abort_asynch(&_serial); +} + +int SerialBase::set_dma_usage_tx(DMAUsage usage) +{ + if (serial_tx_active(&_serial)) { + return -1; + } + _tx_usage = usage; + return 0; +} + +int SerialBase::set_dma_usage_rx(DMAUsage usage) +{ + if (serial_tx_active(&_serial)) { + return -1; + } + _rx_usage = usage; + return 0; +} + +int SerialBase::read(uint8_t *buffer, int length, const event_callback_t& callback, int event, unsigned char char_match) +{ + if (serial_rx_active(&_serial)) { + return -1; // transaction ongoing + } + start_read((void*)buffer, length, 8, callback, event, char_match); + return 0; +} + + +int SerialBase::read(uint16_t *buffer, int length, const event_callback_t& callback, int event, unsigned char char_match) +{ + if (serial_rx_active(&_serial)) { + return -1; // transaction ongoing + } + start_read((void*)buffer, length, 16, callback, event, char_match); + return 0; +} + + +void SerialBase::start_read(void *buffer, int buffer_size, char buffer_width, const event_callback_t& callback, int event, unsigned char char_match) +{ + _rx_callback = callback; + _thunk_irq.callback(&SerialBase::interrupt_handler_asynch); + serial_rx_asynch(&_serial, buffer, buffer_size, buffer_width, _thunk_irq.entry(), event, char_match, _rx_usage); +} + +void SerialBase::interrupt_handler_asynch(void) +{ + int event = serial_irq_handler_asynch(&_serial); + int rx_event = event & SERIAL_EVENT_RX_MASK; + if (_rx_callback && rx_event) { + _rx_callback.call(rx_event); + } + + int tx_event = event & SERIAL_EVENT_TX_MASK; + if (_tx_callback && tx_event) { + _tx_callback.call(tx_event); + } +} + +#endif + +} // namespace mbed + +#endif