Andrew SaLoutos / mbed-dev-STM-lean

From Ben Katz mbed-dev library. Removed unnecessary target files to reduce the overall size by a factor of 10 to make it easier to import into the online IDE.

Dependents:   motor_driver motor_driver_screaming_fix

drivers/I2C.cpp@0:083111ae2a11, 2020-11-26 (annotated)

Committer:
saloutos
Date:
Thu Nov 26 04:08:56 2020 +0000
Revision:
0:083111ae2a11
first commit of leaned mbed dev lib

Who changed what in which revision?

UserRevisionLine numberNew contents of line
saloutos 0:083111ae2a11 1 /* mbed Microcontroller Library
saloutos 0:083111ae2a11 2 * Copyright (c) 2006-2015 ARM Limited
saloutos 0:083111ae2a11 3 *
saloutos 0:083111ae2a11 4 * Licensed under the Apache License, Version 2.0 (the "License");
saloutos 0:083111ae2a11 5 * you may not use this file except in compliance with the License.
saloutos 0:083111ae2a11 6 * You may obtain a copy of the License at
saloutos 0:083111ae2a11 7 *
saloutos 0:083111ae2a11 8 * http://www.apache.org/licenses/LICENSE-2.0
saloutos 0:083111ae2a11 9 *
saloutos 0:083111ae2a11 10 * Unless required by applicable law or agreed to in writing, software
saloutos 0:083111ae2a11 11 * distributed under the License is distributed on an "AS IS" BASIS,
saloutos 0:083111ae2a11 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
saloutos 0:083111ae2a11 13 * See the License for the specific language governing permissions and
saloutos 0:083111ae2a11 14 * limitations under the License.
saloutos 0:083111ae2a11 15 */
saloutos 0:083111ae2a11 16 #include "drivers/I2C.h"
saloutos 0:083111ae2a11 17
saloutos 0:083111ae2a11 18 #if DEVICE_I2C
saloutos 0:083111ae2a11 19
saloutos 0:083111ae2a11 20 #if DEVICE_I2C_ASYNCH
saloutos 0:083111ae2a11 21 #include "platform/mbed_sleep.h"
saloutos 0:083111ae2a11 22 #endif
saloutos 0:083111ae2a11 23
saloutos 0:083111ae2a11 24 namespace mbed {
saloutos 0:083111ae2a11 25
saloutos 0:083111ae2a11 26 I2C *I2C::_owner = NULL;
saloutos 0:083111ae2a11 27 SingletonPtr<PlatformMutex> I2C::_mutex;
saloutos 0:083111ae2a11 28
saloutos 0:083111ae2a11 29 I2C::I2C(PinName sda, PinName scl) :
saloutos 0:083111ae2a11 30 #if DEVICE_I2C_ASYNCH
saloutos 0:083111ae2a11 31 _irq(this), _usage(DMA_USAGE_NEVER),
saloutos 0:083111ae2a11 32 #endif
saloutos 0:083111ae2a11 33 _i2c(), _hz(100000) {
saloutos 0:083111ae2a11 34 // No lock needed in the constructor
saloutos 0:083111ae2a11 35
saloutos 0:083111ae2a11 36 // The init function also set the frequency to 100000
saloutos 0:083111ae2a11 37 i2c_init(&_i2c, sda, scl);
saloutos 0:083111ae2a11 38
saloutos 0:083111ae2a11 39 // Used to avoid unnecessary frequency updates
saloutos 0:083111ae2a11 40 _owner = this;
saloutos 0:083111ae2a11 41 }
saloutos 0:083111ae2a11 42
saloutos 0:083111ae2a11 43 void I2C::frequency(int hz) {
saloutos 0:083111ae2a11 44 lock();
saloutos 0:083111ae2a11 45 _hz = hz;
saloutos 0:083111ae2a11 46
saloutos 0:083111ae2a11 47 // We want to update the frequency even if we are already the bus owners
saloutos 0:083111ae2a11 48 i2c_frequency(&_i2c, _hz);
saloutos 0:083111ae2a11 49
saloutos 0:083111ae2a11 50 // Updating the frequency of the bus we become the owners of it
saloutos 0:083111ae2a11 51 _owner = this;
saloutos 0:083111ae2a11 52 unlock();
saloutos 0:083111ae2a11 53 }
saloutos 0:083111ae2a11 54
saloutos 0:083111ae2a11 55 void I2C::aquire() {
saloutos 0:083111ae2a11 56 lock();
saloutos 0:083111ae2a11 57 if (_owner != this) {
saloutos 0:083111ae2a11 58 i2c_frequency(&_i2c, _hz);
saloutos 0:083111ae2a11 59 _owner = this;
saloutos 0:083111ae2a11 60 }
saloutos 0:083111ae2a11 61 unlock();
saloutos 0:083111ae2a11 62 }
saloutos 0:083111ae2a11 63
saloutos 0:083111ae2a11 64 // write - Master Transmitter Mode
saloutos 0:083111ae2a11 65 int I2C::write(int address, const char* data, int length, bool repeated) {
saloutos 0:083111ae2a11 66 lock();
saloutos 0:083111ae2a11 67 aquire();
saloutos 0:083111ae2a11 68
saloutos 0:083111ae2a11 69 int stop = (repeated) ? 0 : 1;
saloutos 0:083111ae2a11 70 int written = i2c_write(&_i2c, address, data, length, stop);
saloutos 0:083111ae2a11 71
saloutos 0:083111ae2a11 72 unlock();
saloutos 0:083111ae2a11 73 return length != written;
saloutos 0:083111ae2a11 74 }
saloutos 0:083111ae2a11 75
saloutos 0:083111ae2a11 76 int I2C::write(int data) {
saloutos 0:083111ae2a11 77 lock();
saloutos 0:083111ae2a11 78 int ret = i2c_byte_write(&_i2c, data);
saloutos 0:083111ae2a11 79 unlock();
saloutos 0:083111ae2a11 80 return ret;
saloutos 0:083111ae2a11 81 }
saloutos 0:083111ae2a11 82
saloutos 0:083111ae2a11 83 // read - Master Reciever Mode
saloutos 0:083111ae2a11 84 int I2C::read(int address, char* data, int length, bool repeated) {
saloutos 0:083111ae2a11 85 lock();
saloutos 0:083111ae2a11 86 aquire();
saloutos 0:083111ae2a11 87
saloutos 0:083111ae2a11 88 int stop = (repeated) ? 0 : 1;
saloutos 0:083111ae2a11 89 int read = i2c_read(&_i2c, address, data, length, stop);
saloutos 0:083111ae2a11 90
saloutos 0:083111ae2a11 91 unlock();
saloutos 0:083111ae2a11 92 return length != read;
saloutos 0:083111ae2a11 93 }
saloutos 0:083111ae2a11 94
saloutos 0:083111ae2a11 95 int I2C::read(int ack) {
saloutos 0:083111ae2a11 96 lock();
saloutos 0:083111ae2a11 97 int ret;
saloutos 0:083111ae2a11 98 if (ack) {
saloutos 0:083111ae2a11 99 ret = i2c_byte_read(&_i2c, 0);
saloutos 0:083111ae2a11 100 } else {
saloutos 0:083111ae2a11 101 ret = i2c_byte_read(&_i2c, 1);
saloutos 0:083111ae2a11 102 }
saloutos 0:083111ae2a11 103 unlock();
saloutos 0:083111ae2a11 104 return ret;
saloutos 0:083111ae2a11 105 }
saloutos 0:083111ae2a11 106
saloutos 0:083111ae2a11 107 void I2C::start(void) {
saloutos 0:083111ae2a11 108 lock();
saloutos 0:083111ae2a11 109 i2c_start(&_i2c);
saloutos 0:083111ae2a11 110 unlock();
saloutos 0:083111ae2a11 111 }
saloutos 0:083111ae2a11 112
saloutos 0:083111ae2a11 113 void I2C::stop(void) {
saloutos 0:083111ae2a11 114 lock();
saloutos 0:083111ae2a11 115 i2c_stop(&_i2c);
saloutos 0:083111ae2a11 116 unlock();
saloutos 0:083111ae2a11 117 }
saloutos 0:083111ae2a11 118
saloutos 0:083111ae2a11 119 void I2C::lock() {
saloutos 0:083111ae2a11 120 _mutex->lock();
saloutos 0:083111ae2a11 121 }
saloutos 0:083111ae2a11 122
saloutos 0:083111ae2a11 123 void I2C::unlock() {
saloutos 0:083111ae2a11 124 _mutex->unlock();
saloutos 0:083111ae2a11 125 }
saloutos 0:083111ae2a11 126
saloutos 0:083111ae2a11 127 #if DEVICE_I2C_ASYNCH
saloutos 0:083111ae2a11 128
saloutos 0:083111ae2a11 129 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)
saloutos 0:083111ae2a11 130 {
saloutos 0:083111ae2a11 131 lock();
saloutos 0:083111ae2a11 132 if (i2c_active(&_i2c)) {
saloutos 0:083111ae2a11 133 unlock();
saloutos 0:083111ae2a11 134 return -1; // transaction ongoing
saloutos 0:083111ae2a11 135 }
saloutos 0:083111ae2a11 136 sleep_manager_lock_deep_sleep();
saloutos 0:083111ae2a11 137 aquire();
saloutos 0:083111ae2a11 138
saloutos 0:083111ae2a11 139 _callback = callback;
saloutos 0:083111ae2a11 140 int stop = (repeated) ? 0 : 1;
saloutos 0:083111ae2a11 141 _irq.callback(&I2C::irq_handler_asynch);
saloutos 0:083111ae2a11 142 i2c_transfer_asynch(&_i2c, (void *)tx_buffer, tx_length, (void *)rx_buffer, rx_length, address, stop, _irq.entry(), event, _usage);
saloutos 0:083111ae2a11 143 unlock();
saloutos 0:083111ae2a11 144 return 0;
saloutos 0:083111ae2a11 145 }
saloutos 0:083111ae2a11 146
saloutos 0:083111ae2a11 147 void I2C::abort_transfer(void)
saloutos 0:083111ae2a11 148 {
saloutos 0:083111ae2a11 149 lock();
saloutos 0:083111ae2a11 150 i2c_abort_asynch(&_i2c);
saloutos 0:083111ae2a11 151 sleep_manager_unlock_deep_sleep();
saloutos 0:083111ae2a11 152 unlock();
saloutos 0:083111ae2a11 153 }
saloutos 0:083111ae2a11 154
saloutos 0:083111ae2a11 155 void I2C::irq_handler_asynch(void)
saloutos 0:083111ae2a11 156 {
saloutos 0:083111ae2a11 157 int event = i2c_irq_handler_asynch(&_i2c);
saloutos 0:083111ae2a11 158 if (_callback && event) {
saloutos 0:083111ae2a11 159 _callback.call(event);
saloutos 0:083111ae2a11 160 }
saloutos 0:083111ae2a11 161 if (event) {
saloutos 0:083111ae2a11 162 sleep_manager_unlock_deep_sleep();
saloutos 0:083111ae2a11 163 }
saloutos 0:083111ae2a11 164
saloutos 0:083111ae2a11 165 }
saloutos 0:083111ae2a11 166
saloutos 0:083111ae2a11 167
saloutos 0:083111ae2a11 168 #endif
saloutos 0:083111ae2a11 169
saloutos 0:083111ae2a11 170 } // namespace mbed
saloutos 0:083111ae2a11 171
saloutos 0:083111ae2a11 172 #endif