Jonathan Piat / mbed-src

mbed library sources

Fork of mbed-src by mbed official

common/I2C.cpp@525:c320967f86b9, 2015-04-28 (annotated)

Committer:
mbed_official
Date:
Tue Apr 28 11:45:12 2015 +0100
Revision:
525:c320967f86b9
Parent:
212:34d62c0b2af6 
Synchronized with git revision 299385b8331142b9dc524da7a986536f60b14553



Full URL: https://github.com/mbedmicro/mbed/commit/299385b8331142b9dc524da7a986536f60b14553/



Add in Silicon Labs targets with asynchronous API support

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bogdanm 13:0645d8841f51 1 /* mbed Microcontroller Library
mbed_official 525:c320967f86b9 2 * Copyright (c) 2006-2015 ARM Limited
bogdanm 13:0645d8841f51 3 *
bogdanm 13:0645d8841f51 4 * Licensed under the Apache License, Version 2.0 (the "License");
bogdanm 13:0645d8841f51 5 * you may not use this file except in compliance with the License.
bogdanm 13:0645d8841f51 6 * You may obtain a copy of the License at
bogdanm 13:0645d8841f51 7 *
bogdanm 13:0645d8841f51 8 * http://www.apache.org/licenses/LICENSE-2.0
bogdanm 13:0645d8841f51 9 *
bogdanm 13:0645d8841f51 10 * Unless required by applicable law or agreed to in writing, software
bogdanm 13:0645d8841f51 11 * distributed under the License is distributed on an "AS IS" BASIS,
bogdanm 13:0645d8841f51 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
bogdanm 13:0645d8841f51 13 * See the License for the specific language governing permissions and
bogdanm 13:0645d8841f51 14 * limitations under the License.
bogdanm 13:0645d8841f51 15 */
bogdanm 13:0645d8841f51 16 #include "I2C.h"
bogdanm 13:0645d8841f51 17
bogdanm 13:0645d8841f51 18 #if DEVICE_I2C
bogdanm 13:0645d8841f51 19
bogdanm 13:0645d8841f51 20 namespace mbed {
bogdanm 13:0645d8841f51 21
bogdanm 13:0645d8841f51 22 I2C *I2C::_owner = NULL;
bogdanm 13:0645d8841f51 23
mbed_official 525:c320967f86b9 24 I2C::I2C(PinName sda, PinName scl) :
mbed_official 525:c320967f86b9 25 #if DEVICE_I2C_ASYNCH
mbed_official 525:c320967f86b9 26 _irq(this), _usage(DMA_USAGE_NEVER),
mbed_official 525:c320967f86b9 27 #endif
mbed_official 525:c320967f86b9 28 _i2c(), _hz(100000) {
bogdanm 13:0645d8841f51 29 // The init function also set the frequency to 100000
bogdanm 13:0645d8841f51 30 i2c_init(&_i2c, sda, scl);
bogdanm 13:0645d8841f51 31
bogdanm 13:0645d8841f51 32 // Used to avoid unnecessary frequency updates
bogdanm 13:0645d8841f51 33 _owner = this;
bogdanm 13:0645d8841f51 34 }
bogdanm 13:0645d8841f51 35
bogdanm 13:0645d8841f51 36 void I2C::frequency(int hz) {
bogdanm 13:0645d8841f51 37 _hz = hz;
bogdanm 13:0645d8841f51 38
bogdanm 13:0645d8841f51 39 // We want to update the frequency even if we are already the bus owners
bogdanm 13:0645d8841f51 40 i2c_frequency(&_i2c, _hz);
bogdanm 13:0645d8841f51 41
bogdanm 13:0645d8841f51 42 // Updating the frequency of the bus we become the owners of it
bogdanm 13:0645d8841f51 43 _owner = this;
bogdanm 13:0645d8841f51 44 }
bogdanm 13:0645d8841f51 45
bogdanm 13:0645d8841f51 46 void I2C::aquire() {
bogdanm 13:0645d8841f51 47 if (_owner != this) {
bogdanm 13:0645d8841f51 48 i2c_frequency(&_i2c, _hz);
bogdanm 13:0645d8841f51 49 _owner = this;
bogdanm 13:0645d8841f51 50 }
bogdanm 13:0645d8841f51 51 }
bogdanm 13:0645d8841f51 52
bogdanm 13:0645d8841f51 53 // write - Master Transmitter Mode
bogdanm 13:0645d8841f51 54 int I2C::write(int address, const char* data, int length, bool repeated) {
bogdanm 13:0645d8841f51 55 aquire();
bogdanm 13:0645d8841f51 56
bogdanm 13:0645d8841f51 57 int stop = (repeated) ? 0 : 1;
bogdanm 13:0645d8841f51 58 int written = i2c_write(&_i2c, address, data, length, stop);
bogdanm 13:0645d8841f51 59
bogdanm 13:0645d8841f51 60 return length != written;
bogdanm 13:0645d8841f51 61 }
bogdanm 13:0645d8841f51 62
bogdanm 13:0645d8841f51 63 int I2C::write(int data) {
bogdanm 13:0645d8841f51 64 return i2c_byte_write(&_i2c, data);
bogdanm 13:0645d8841f51 65 }
bogdanm 13:0645d8841f51 66
bogdanm 13:0645d8841f51 67 // read - Master Reciever Mode
bogdanm 13:0645d8841f51 68 int I2C::read(int address, char* data, int length, bool repeated) {
bogdanm 13:0645d8841f51 69 aquire();
bogdanm 13:0645d8841f51 70
bogdanm 13:0645d8841f51 71 int stop = (repeated) ? 0 : 1;
bogdanm 13:0645d8841f51 72 int read = i2c_read(&_i2c, address, data, length, stop);
bogdanm 13:0645d8841f51 73
bogdanm 13:0645d8841f51 74 return length != read;
bogdanm 13:0645d8841f51 75 }
bogdanm 13:0645d8841f51 76
bogdanm 13:0645d8841f51 77 int I2C::read(int ack) {
bogdanm 13:0645d8841f51 78 if (ack) {
bogdanm 13:0645d8841f51 79 return i2c_byte_read(&_i2c, 0);
bogdanm 13:0645d8841f51 80 } else {
bogdanm 13:0645d8841f51 81 return i2c_byte_read(&_i2c, 1);
bogdanm 13:0645d8841f51 82 }
bogdanm 13:0645d8841f51 83 }
bogdanm 13:0645d8841f51 84
bogdanm 13:0645d8841f51 85 void I2C::start(void) {
bogdanm 13:0645d8841f51 86 i2c_start(&_i2c);
bogdanm 13:0645d8841f51 87 }
bogdanm 13:0645d8841f51 88
bogdanm 13:0645d8841f51 89 void I2C::stop(void) {
bogdanm 13:0645d8841f51 90 i2c_stop(&_i2c);
bogdanm 13:0645d8841f51 91 }
bogdanm 13:0645d8841f51 92
mbed_official 525:c320967f86b9 93 #if DEVICE_I2C_ASYNCH
mbed_official 525:c320967f86b9 94
mbed_official 525:c320967f86b9 95 int I2C::transfer(int address, char *tx_buffer, int tx_length, char *rx_buffer, int rx_length, const event_callback_t& callback, int event, bool repeated)
mbed_official 525:c320967f86b9 96 {
mbed_official 525:c320967f86b9 97 if (i2c_active(&_i2c)) {
mbed_official 525:c320967f86b9 98 return -1; // transaction ongoing
mbed_official 525:c320967f86b9 99 }
mbed_official 525:c320967f86b9 100 aquire();
mbed_official 525:c320967f86b9 101
mbed_official 525:c320967f86b9 102 _callback = callback;
mbed_official 525:c320967f86b9 103 int stop = (repeated) ? 0 : 1;
mbed_official 525:c320967f86b9 104 _irq.callback(&I2C::irq_handler_asynch);
mbed_official 525:c320967f86b9 105 i2c_transfer_asynch(&_i2c, (void *)tx_buffer, tx_length, (void *)rx_buffer, rx_length, address, stop, _irq.entry(), event, _usage);
mbed_official 525:c320967f86b9 106 return 0;
mbed_official 525:c320967f86b9 107 }
mbed_official 525:c320967f86b9 108
mbed_official 525:c320967f86b9 109 void I2C::abort_transfer(void)
mbed_official 525:c320967f86b9 110 {
mbed_official 525:c320967f86b9 111 i2c_abort_asynch(&_i2c);
mbed_official 525:c320967f86b9 112 }
mbed_official 525:c320967f86b9 113
mbed_official 525:c320967f86b9 114 void I2C::irq_handler_asynch(void)
mbed_official 525:c320967f86b9 115 {
mbed_official 525:c320967f86b9 116 int event = i2c_irq_handler_asynch(&_i2c);
mbed_official 525:c320967f86b9 117 if (_callback && event) {
mbed_official 525:c320967f86b9 118 _callback.call(event);
mbed_official 525:c320967f86b9 119 }
mbed_official 525:c320967f86b9 120
mbed_official 525:c320967f86b9 121 }
mbed_official 525:c320967f86b9 122
mbed_official 525:c320967f86b9 123
mbed_official 525:c320967f86b9 124 #endif
mbed_official 525:c320967f86b9 125
bogdanm 13:0645d8841f51 126 } // namespace mbed
bogdanm 13:0645d8841f51 127
bogdanm 13:0645d8841f51 128 #endif