Daniel Vizcaya / Mbed OS 04_RTOS_Embebidos

Entrega 3er corte - sistemas embebidos

mbed-os/drivers/I2C.cpp@1:fcdb45ee95b9, 2018-05-30 (annotated)

Committer:
Bethory
Date:
Wed May 30 04:46:28 2018 +0000
Revision:
1:fcdb45ee95b9
Parent:
0:6ad07c9019fd 
Entrega Final

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Bethory 0:6ad07c9019fd 1 /* mbed Microcontroller Library
Bethory 0:6ad07c9019fd 2 * Copyright (c) 2006-2015 ARM Limited
Bethory 0:6ad07c9019fd 3 *
Bethory 0:6ad07c9019fd 4 * Licensed under the Apache License, Version 2.0 (the "License");
Bethory 0:6ad07c9019fd 5 * you may not use this file except in compliance with the License.
Bethory 0:6ad07c9019fd 6 * You may obtain a copy of the License at
Bethory 0:6ad07c9019fd 7 *
Bethory 0:6ad07c9019fd 8 * http://www.apache.org/licenses/LICENSE-2.0
Bethory 0:6ad07c9019fd 9 *
Bethory 0:6ad07c9019fd 10 * Unless required by applicable law or agreed to in writing, software
Bethory 0:6ad07c9019fd 11 * distributed under the License is distributed on an "AS IS" BASIS,
Bethory 0:6ad07c9019fd 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
Bethory 0:6ad07c9019fd 13 * See the License for the specific language governing permissions and
Bethory 0:6ad07c9019fd 14 * limitations under the License.
Bethory 0:6ad07c9019fd 15 */
Bethory 0:6ad07c9019fd 16 #include "drivers/I2C.h"
Bethory 0:6ad07c9019fd 17
Bethory 0:6ad07c9019fd 18 #if DEVICE_I2C
Bethory 0:6ad07c9019fd 19
Bethory 0:6ad07c9019fd 20 #if DEVICE_I2C_ASYNCH
Bethory 0:6ad07c9019fd 21 #include "platform/mbed_power_mgmt.h"
Bethory 0:6ad07c9019fd 22 #endif
Bethory 0:6ad07c9019fd 23
Bethory 0:6ad07c9019fd 24 namespace mbed {
Bethory 0:6ad07c9019fd 25
Bethory 0:6ad07c9019fd 26 I2C *I2C::_owner = NULL;
Bethory 0:6ad07c9019fd 27 SingletonPtr<PlatformMutex> I2C::_mutex;
Bethory 0:6ad07c9019fd 28
Bethory 0:6ad07c9019fd 29 I2C::I2C(PinName sda, PinName scl) :
Bethory 0:6ad07c9019fd 30 #if DEVICE_I2C_ASYNCH
Bethory 0:6ad07c9019fd 31 _irq(this), _usage(DMA_USAGE_NEVER), _deep_sleep_locked(false),
Bethory 0:6ad07c9019fd 32 #endif
Bethory 0:6ad07c9019fd 33 _i2c(), _hz(100000)
Bethory 0:6ad07c9019fd 34 {
Bethory 0:6ad07c9019fd 35 // No lock needed in the constructor
Bethory 0:6ad07c9019fd 36
Bethory 0:6ad07c9019fd 37 // The init function also set the frequency to 100000
Bethory 0:6ad07c9019fd 38 i2c_init(&_i2c, sda, scl);
Bethory 0:6ad07c9019fd 39
Bethory 0:6ad07c9019fd 40 // Used to avoid unnecessary frequency updates
Bethory 0:6ad07c9019fd 41 _owner = this;
Bethory 0:6ad07c9019fd 42 }
Bethory 0:6ad07c9019fd 43
Bethory 0:6ad07c9019fd 44 void I2C::frequency(int hz) {
Bethory 0:6ad07c9019fd 45 lock();
Bethory 0:6ad07c9019fd 46 _hz = hz;
Bethory 0:6ad07c9019fd 47
Bethory 0:6ad07c9019fd 48 // We want to update the frequency even if we are already the bus owners
Bethory 0:6ad07c9019fd 49 i2c_frequency(&_i2c, _hz);
Bethory 0:6ad07c9019fd 50
Bethory 0:6ad07c9019fd 51 // Updating the frequency of the bus we become the owners of it
Bethory 0:6ad07c9019fd 52 _owner = this;
Bethory 0:6ad07c9019fd 53 unlock();
Bethory 0:6ad07c9019fd 54 }
Bethory 0:6ad07c9019fd 55
Bethory 0:6ad07c9019fd 56 void I2C::aquire() {
Bethory 0:6ad07c9019fd 57 lock();
Bethory 0:6ad07c9019fd 58 if (_owner != this) {
Bethory 0:6ad07c9019fd 59 i2c_frequency(&_i2c, _hz);
Bethory 0:6ad07c9019fd 60 _owner = this;
Bethory 0:6ad07c9019fd 61 }
Bethory 0:6ad07c9019fd 62 unlock();
Bethory 0:6ad07c9019fd 63 }
Bethory 0:6ad07c9019fd 64
Bethory 0:6ad07c9019fd 65 // write - Master Transmitter Mode
Bethory 0:6ad07c9019fd 66 int I2C::write(int address, const char* data, int length, bool repeated) {
Bethory 0:6ad07c9019fd 67 lock();
Bethory 0:6ad07c9019fd 68 aquire();
Bethory 0:6ad07c9019fd 69
Bethory 0:6ad07c9019fd 70 int stop = (repeated) ? 0 : 1;
Bethory 0:6ad07c9019fd 71 int written = i2c_write(&_i2c, address, data, length, stop);
Bethory 0:6ad07c9019fd 72
Bethory 0:6ad07c9019fd 73 unlock();
Bethory 0:6ad07c9019fd 74 return length != written;
Bethory 0:6ad07c9019fd 75 }
Bethory 0:6ad07c9019fd 76
Bethory 0:6ad07c9019fd 77 int I2C::write(int data) {
Bethory 0:6ad07c9019fd 78 lock();
Bethory 0:6ad07c9019fd 79 int ret = i2c_byte_write(&_i2c, data);
Bethory 0:6ad07c9019fd 80 unlock();
Bethory 0:6ad07c9019fd 81 return ret;
Bethory 0:6ad07c9019fd 82 }
Bethory 0:6ad07c9019fd 83
Bethory 0:6ad07c9019fd 84 // read - Master Receiver Mode
Bethory 0:6ad07c9019fd 85 int I2C::read(int address, char* data, int length, bool repeated) {
Bethory 0:6ad07c9019fd 86 lock();
Bethory 0:6ad07c9019fd 87 aquire();
Bethory 0:6ad07c9019fd 88
Bethory 0:6ad07c9019fd 89 int stop = (repeated) ? 0 : 1;
Bethory 0:6ad07c9019fd 90 int read = i2c_read(&_i2c, address, data, length, stop);
Bethory 0:6ad07c9019fd 91
Bethory 0:6ad07c9019fd 92 unlock();
Bethory 0:6ad07c9019fd 93 return length != read;
Bethory 0:6ad07c9019fd 94 }
Bethory 0:6ad07c9019fd 95
Bethory 0:6ad07c9019fd 96 int I2C::read(int ack) {
Bethory 0:6ad07c9019fd 97 lock();
Bethory 0:6ad07c9019fd 98 int ret;
Bethory 0:6ad07c9019fd 99 if (ack) {
Bethory 0:6ad07c9019fd 100 ret = i2c_byte_read(&_i2c, 0);
Bethory 0:6ad07c9019fd 101 } else {
Bethory 0:6ad07c9019fd 102 ret = i2c_byte_read(&_i2c, 1);
Bethory 0:6ad07c9019fd 103 }
Bethory 0:6ad07c9019fd 104 unlock();
Bethory 0:6ad07c9019fd 105 return ret;
Bethory 0:6ad07c9019fd 106 }
Bethory 0:6ad07c9019fd 107
Bethory 0:6ad07c9019fd 108 void I2C::start(void) {
Bethory 0:6ad07c9019fd 109 lock();
Bethory 0:6ad07c9019fd 110 i2c_start(&_i2c);
Bethory 0:6ad07c9019fd 111 unlock();
Bethory 0:6ad07c9019fd 112 }
Bethory 0:6ad07c9019fd 113
Bethory 0:6ad07c9019fd 114 void I2C::stop(void) {
Bethory 0:6ad07c9019fd 115 lock();
Bethory 0:6ad07c9019fd 116 i2c_stop(&_i2c);
Bethory 0:6ad07c9019fd 117 unlock();
Bethory 0:6ad07c9019fd 118 }
Bethory 0:6ad07c9019fd 119
Bethory 0:6ad07c9019fd 120 void I2C::lock() {
Bethory 0:6ad07c9019fd 121 _mutex->lock();
Bethory 0:6ad07c9019fd 122 }
Bethory 0:6ad07c9019fd 123
Bethory 0:6ad07c9019fd 124 void I2C::unlock() {
Bethory 0:6ad07c9019fd 125 _mutex->unlock();
Bethory 0:6ad07c9019fd 126 }
Bethory 0:6ad07c9019fd 127
Bethory 0:6ad07c9019fd 128 #if DEVICE_I2C_ASYNCH
Bethory 0:6ad07c9019fd 129
Bethory 0:6ad07c9019fd 130 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)
Bethory 0:6ad07c9019fd 131 {
Bethory 0:6ad07c9019fd 132 lock();
Bethory 0:6ad07c9019fd 133 if (i2c_active(&_i2c)) {
Bethory 0:6ad07c9019fd 134 unlock();
Bethory 0:6ad07c9019fd 135 return -1; // transaction ongoing
Bethory 0:6ad07c9019fd 136 }
Bethory 0:6ad07c9019fd 137 lock_deep_sleep();
Bethory 0:6ad07c9019fd 138 aquire();
Bethory 0:6ad07c9019fd 139
Bethory 0:6ad07c9019fd 140 _callback = callback;
Bethory 0:6ad07c9019fd 141 int stop = (repeated) ? 0 : 1;
Bethory 0:6ad07c9019fd 142 _irq.callback(&I2C::irq_handler_asynch);
Bethory 0:6ad07c9019fd 143 i2c_transfer_asynch(&_i2c, (void *)tx_buffer, tx_length, (void *)rx_buffer, rx_length, address, stop, _irq.entry(), event, _usage);
Bethory 0:6ad07c9019fd 144 unlock();
Bethory 0:6ad07c9019fd 145 return 0;
Bethory 0:6ad07c9019fd 146 }
Bethory 0:6ad07c9019fd 147
Bethory 0:6ad07c9019fd 148 void I2C::abort_transfer(void)
Bethory 0:6ad07c9019fd 149 {
Bethory 0:6ad07c9019fd 150 lock();
Bethory 0:6ad07c9019fd 151 i2c_abort_asynch(&_i2c);
Bethory 0:6ad07c9019fd 152 unlock_deep_sleep();
Bethory 0:6ad07c9019fd 153 unlock();
Bethory 0:6ad07c9019fd 154 }
Bethory 0:6ad07c9019fd 155
Bethory 0:6ad07c9019fd 156 void I2C::irq_handler_asynch(void)
Bethory 0:6ad07c9019fd 157 {
Bethory 0:6ad07c9019fd 158 int event = i2c_irq_handler_asynch(&_i2c);
Bethory 0:6ad07c9019fd 159 if (_callback && event) {
Bethory 0:6ad07c9019fd 160 _callback.call(event);
Bethory 0:6ad07c9019fd 161 }
Bethory 0:6ad07c9019fd 162 if (event) {
Bethory 0:6ad07c9019fd 163 unlock_deep_sleep();
Bethory 0:6ad07c9019fd 164 }
Bethory 0:6ad07c9019fd 165
Bethory 0:6ad07c9019fd 166 }
Bethory 0:6ad07c9019fd 167
Bethory 0:6ad07c9019fd 168 void I2C::lock_deep_sleep()
Bethory 0:6ad07c9019fd 169 {
Bethory 0:6ad07c9019fd 170 if (_deep_sleep_locked == false) {
Bethory 0:6ad07c9019fd 171 sleep_manager_lock_deep_sleep();
Bethory 0:6ad07c9019fd 172 _deep_sleep_locked = true;
Bethory 0:6ad07c9019fd 173 }
Bethory 0:6ad07c9019fd 174 }
Bethory 0:6ad07c9019fd 175
Bethory 0:6ad07c9019fd 176 void I2C::unlock_deep_sleep()
Bethory 0:6ad07c9019fd 177 {
Bethory 0:6ad07c9019fd 178 if (_deep_sleep_locked == true) {
Bethory 0:6ad07c9019fd 179 sleep_manager_unlock_deep_sleep();
Bethory 0:6ad07c9019fd 180 _deep_sleep_locked = false;
Bethory 0:6ad07c9019fd 181 }
Bethory 0:6ad07c9019fd 182 }
Bethory 0:6ad07c9019fd 183
Bethory 0:6ad07c9019fd 184 #endif
Bethory 0:6ad07c9019fd 185
Bethory 0:6ad07c9019fd 186 } // namespace mbed
Bethory 0:6ad07c9019fd 187
Bethory 0:6ad07c9019fd 188 #endif