RTC auf true
drivers/I2C.cpp
- Committer:
- kevman
- Date:
- 2018-11-28
- Revision:
- 0:38ceb79fef03
File content as of revision 0:38ceb79fef03:
/* mbed Microcontroller Library * Copyright (c) 2006-2015 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/I2C.h" #if DEVICE_I2C #if DEVICE_I2C_ASYNCH #include "platform/mbed_power_mgmt.h" #endif namespace mbed { I2C *I2C::_owner = NULL; SingletonPtr<PlatformMutex> I2C::_mutex; I2C::I2C(PinName sda, PinName scl) : #if DEVICE_I2C_ASYNCH _irq(this), _usage(DMA_USAGE_NEVER), _deep_sleep_locked(false), #endif _i2c(), _hz(100000) { // No lock needed in the constructor // The init function also set the frequency to 100000 i2c_init(&_i2c, sda, scl); // Used to avoid unnecessary frequency updates _owner = this; } void I2C::frequency(int hz) { lock(); _hz = hz; // We want to update the frequency even if we are already the bus owners i2c_frequency(&_i2c, _hz); // Updating the frequency of the bus we become the owners of it _owner = this; unlock(); } void I2C::aquire() { lock(); if (_owner != this) { i2c_frequency(&_i2c, _hz); _owner = this; } unlock(); } // write - Master Transmitter Mode int I2C::write(int address, const char *data, int length, bool repeated) { lock(); aquire(); int stop = (repeated) ? 0 : 1; int written = i2c_write(&_i2c, address, data, length, stop); unlock(); return length != written; } int I2C::write(int data) { lock(); int ret = i2c_byte_write(&_i2c, data); unlock(); return ret; } // read - Master Receiver Mode int I2C::read(int address, char *data, int length, bool repeated) { lock(); aquire(); int stop = (repeated) ? 0 : 1; int read = i2c_read(&_i2c, address, data, length, stop); unlock(); return length != read; } int I2C::read(int ack) { lock(); int ret; if (ack) { ret = i2c_byte_read(&_i2c, 0); } else { ret = i2c_byte_read(&_i2c, 1); } unlock(); return ret; } void I2C::start(void) { lock(); i2c_start(&_i2c); unlock(); } void I2C::stop(void) { lock(); i2c_stop(&_i2c); unlock(); } void I2C::lock() { _mutex->lock(); } void I2C::unlock() { _mutex->unlock(); } #if DEVICE_I2C_ASYNCH int I2C::transfer(int address, const char *tx_buffer, int tx_length, char *rx_buffer, int rx_length, const event_callback_t &callback, int event, bool repeated) { lock(); if (i2c_active(&_i2c)) { unlock(); return -1; // transaction ongoing } lock_deep_sleep(); aquire(); _callback = callback; int stop = (repeated) ? 0 : 1; _irq.callback(&I2C::irq_handler_asynch); i2c_transfer_asynch(&_i2c, (void *)tx_buffer, tx_length, (void *)rx_buffer, rx_length, address, stop, _irq.entry(), event, _usage); unlock(); return 0; } void I2C::abort_transfer(void) { lock(); i2c_abort_asynch(&_i2c); unlock_deep_sleep(); unlock(); } void I2C::irq_handler_asynch(void) { int event = i2c_irq_handler_asynch(&_i2c); if (_callback && event) { _callback.call(event); } if (event) { unlock_deep_sleep(); } } void I2C::lock_deep_sleep() { if (_deep_sleep_locked == false) { sleep_manager_lock_deep_sleep(); _deep_sleep_locked = true; } } void I2C::unlock_deep_sleep() { if (_deep_sleep_locked == true) { sleep_manager_unlock_deep_sleep(); _deep_sleep_locked = false; } } #endif } // namespace mbed #endif