Diff: drivers/SerialBase.cpp

Revision:

0:b74591d5ab33

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/drivers/SerialBase.cpp	Mon Dec 11 17:54:04 2017 +0000
@@ -0,0 +1,292 @@
+/* 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/mbed_wait_api.h"
+#include "platform/mbed_critical.h"
+#include "platform/mbed_sleep.h"
+
+#if DEVICE_SERIAL
+
+namespace mbed {
+
+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), _tx_callback(NULL),
+                                                 _rx_callback(NULL),
+#endif
+                                                _serial(), _baud(baud) {
+    // No lock needed in the constructor
+
+    for (size_t i = 0; i < sizeof _irq / sizeof _irq[0]; i++) {
+        _irq[i] = NULL;
+    }
+
+    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) {
+        // lock deep sleep only the first time
+        if (!_irq[type]) {
+            sleep_manager_lock_deep_sleep();
+        } 
+        _irq[type] = func;
+        serial_irq_set(&_serial, (SerialIrq)type, 1);
+    } else {
+        // unlock deep sleep only the first time
+        if (_irq[type]) {
+            sleep_manager_unlock_deep_sleep();
+        } 
+        _irq[type] = NULL;
+        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;
+    if (handler->_irq[irq_type]) {
+        handler->_irq[irq_type]();
+    }
+}
+
+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
+}
+
+SerialBase::~SerialBase()
+{
+    // No lock needed in destructor
+
+    // Detaching interrupts releases the sleep lock if it was locked
+    for (int irq = 0; irq < IrqCnt; irq++) {
+        attach(NULL, (IrqType)irq);
+    }
+}
+
+#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);
+    sleep_manager_lock_deep_sleep();
+    serial_tx_asynch(&_serial, buffer, buffer_size, buffer_width, _thunk_irq.entry(), event, _tx_usage);
+}
+
+void SerialBase::abort_write(void)
+{
+    // rx might still be active
+    if (_rx_callback) {
+        sleep_manager_unlock_deep_sleep();
+    }
+    _tx_callback = NULL;
+    serial_tx_abort_asynch(&_serial);
+}
+
+void SerialBase::abort_read(void)
+{
+    // tx might still be active
+    if (_tx_callback) {
+        sleep_manager_unlock_deep_sleep();
+    }
+    _rx_callback = NULL;
+    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);
+    sleep_manager_lock_deep_sleep();
+    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;
+    bool unlock_deepsleep = false;
+
+    if (_rx_callback && rx_event) {
+        unlock_deepsleep = true;
+        _rx_callback.call(rx_event);
+    }
+
+    int tx_event = event & SERIAL_EVENT_TX_MASK;
+    if (_tx_callback && tx_event) {
+        unlock_deepsleep = true;
+        _tx_callback.call(tx_event);
+    }
+    // unlock if tx or rx events are generated
+    if (unlock_deepsleep) {
+        sleep_manager_unlock_deep_sleep();
+    }
+}
+
+#endif
+
+} // namespace mbed
+
+#endif