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170bdd104f73fa5e64dde9a9c0783781d06b6501
mraa/src/i2c/i2c.c
Thomas Ingleby 170bdd104f spdx: add spdx tags to most files 
Large change that removes the duplicated MIT notice withe a spdx tag

Signed-off-by: Thomas Ingleby <thomas.ingleby@intel.com>
2019-05-23 10:09:12 -07:00

432 lines
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C
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/*
* Author: Brendan Le Foll <brendan.le.foll@intel.com>
* Copyright (c) 2014 Intel Corporation.
*
* Code is modified from the RoadNarrows-robotics i2c library (distributed under
* the MIT license, license is included verbatim under src/i2c/LICENSE)
*
* SPDX-License-Identifier: MIT
*/
#include "i2c.h"
#include "mraa_internal.h"
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <inttypes.h>
#include <sys/types.h>
#include <sys/errno.h>
#if defined(MSYS)
#define __USE_LINUX_IOCTL_DEFS
#endif
#include <sys/ioctl.h>
#include "linux/i2c-dev.h"
#include <errno.h>
#include <string.h>
typedef union i2c_smbus_data_union {
uint8_t byte; ///< data byte
unsigned short word; ///< data short word
uint8_t block[I2C_SMBUS_BLOCK_MAX + 2];
///< block[0] is used for length and one more for PEC
} i2c_smbus_data_t;
typedef struct i2c_smbus_ioctl_data_struct {
uint8_t read_write; ///< operation direction
uint8_t command; ///< ioctl command
int size; ///< data size
i2c_smbus_data_t* data; ///< data
} i2c_smbus_ioctl_data_t;
// static mraa_adv_func_t* func_table;
int
mraa_i2c_smbus_access(int fh, uint8_t read_write, uint8_t command, int size, i2c_smbus_data_t* data)
{
i2c_smbus_ioctl_data_t args;
args.read_write = read_write;
args.command = command;
args.size = size;
args.data = data;
return ioctl(fh, I2C_SMBUS, &args);
}
static mraa_i2c_context
mraa_i2c_init_internal(mraa_adv_func_t* advance_func, unsigned int bus)
{
mraa_result_t status = MRAA_SUCCESS;
if (advance_func == NULL)
return NULL;
mraa_i2c_context dev = (mraa_i2c_context) calloc(1, sizeof(struct _i2c));
if (dev == NULL) {
syslog(LOG_CRIT, "i2c%i_init: Failed to allocate memory for context", bus);
return NULL;
}
dev->advance_func = advance_func;
dev->busnum = bus;
if (IS_FUNC_DEFINED(dev, i2c_init_pre)) {
status = advance_func->i2c_init_pre(bus);
if (status != MRAA_SUCCESS)
goto init_internal_cleanup;
}
if (IS_FUNC_DEFINED(dev, i2c_init_bus_replace)) {
status = dev->advance_func->i2c_init_bus_replace(dev);
if (status != MRAA_SUCCESS)
goto init_internal_cleanup;
} else {
char filepath[32];
snprintf(filepath, 32, "/dev/i2c-%u", bus);
if ((dev->fh = open(filepath, O_RDWR)) < 1) {
syslog(LOG_ERR, "i2c%i_init: Failed to open requested i2c port %s: %s", bus, filepath, strerror(errno));
status = MRAA_ERROR_INVALID_RESOURCE;
goto init_internal_cleanup;
}
if (ioctl(dev->fh, I2C_FUNCS, &dev->funcs) < 0) {
syslog(LOG_CRIT, "i2c%i_init: Failed to get I2C_FUNC map from device: %s", bus, strerror(errno));
dev->funcs = 0;
}
}
if (IS_FUNC_DEFINED(dev, i2c_init_post)) {
status = dev->advance_func->i2c_init_post(dev);
if (status != MRAA_SUCCESS)
goto init_internal_cleanup;
}
init_internal_cleanup:
if (status == MRAA_SUCCESS) {
return dev;
} else {
if (dev != NULL)
free(dev);
return NULL;
}
}
mraa_i2c_context
mraa_i2c_init(int bus)
{
mraa_board_t* board = plat;
if (board == NULL) {
syslog(LOG_ERR, "i2c%i_init: Platform Not Initialised", bus);
return NULL;
}
if (mraa_is_sub_platform_id(bus)) {
syslog(LOG_NOTICE, "i2c%i_init: Using sub platform", bus);
board = board->sub_platform;
if (board == NULL) {
syslog(LOG_ERR, "i2c%i_init: Sub platform Not Initialised", bus);
return NULL;
}
bus = mraa_get_sub_platform_index(bus);
}
syslog(LOG_NOTICE, "i2c_init: Selected bus %d", bus);
if (board->i2c_bus_count == 0) {
syslog(LOG_ERR, "i2c_init: No i2c buses defined in platform");
return NULL;
}
if (bus >= board->i2c_bus_count) {
syslog(LOG_ERR, "i2c_init: i2c%i over i2c bus count", bus);
return NULL;
}
if (board->i2c_bus[bus].bus_id == -1) {
syslog(LOG_ERR, "Invalid i2c bus %i, moving to default i2c bus %i", bus, board->def_i2c_bus);
bus = board->def_i2c_bus;
}
if (!board->no_bus_mux) {
int pos = board->i2c_bus[bus].sda;
if (pos >=0 && board->pins[pos].i2c.mux_total > 0) {
if (mraa_setup_mux_mapped(board->pins[pos].i2c) != MRAA_SUCCESS) {
syslog(LOG_ERR, "i2c%i_init: Failed to set-up i2c sda multiplexer", bus);
return NULL;
}
}
pos = board->i2c_bus[bus].scl;
if (pos >=0 && board->pins[pos].i2c.mux_total > 0) {
if (mraa_setup_mux_mapped(board->pins[pos].i2c) != MRAA_SUCCESS) {
syslog(LOG_ERR, "i2c%i_init: Failed to set-up i2c scl multiplexer", bus);
return NULL;
}
}
}
return mraa_i2c_init_internal(board->adv_func, (unsigned int) board->i2c_bus[bus].bus_id);
}
mraa_i2c_context
mraa_i2c_init_raw(unsigned int bus)
{
return mraa_i2c_init_internal(plat == NULL ? NULL : plat->adv_func, bus);
}
mraa_result_t
mraa_i2c_frequency(mraa_i2c_context dev, mraa_i2c_mode_t mode)
{
if (dev == NULL) {
syslog(LOG_ERR, "i2c: frequency: context is invalid");
return MRAA_ERROR_INVALID_HANDLE;
}
if (IS_FUNC_DEFINED(dev, i2c_set_frequency_replace)) {
return dev->advance_func->i2c_set_frequency_replace(dev, mode);
}
return MRAA_ERROR_FEATURE_NOT_SUPPORTED;
}
int
mraa_i2c_read(mraa_i2c_context dev, uint8_t* data, int length)
{
if (dev == NULL) {
syslog(LOG_ERR, "i2c: read: context is invalid");
return -1;
}
int bytes_read = 0;
if (IS_FUNC_DEFINED(dev, i2c_read_replace)) {
bytes_read = dev->advance_func->i2c_read_replace(dev, data, length);
}
else {
bytes_read = read(dev->fh, data, length);
}
if (bytes_read == length) {
return length;
}
return -1;
}
int
mraa_i2c_read_byte(mraa_i2c_context dev)
{
if (dev == NULL) {
syslog(LOG_ERR, "i2c: read_byte: context is invalid");
return -1;
}
if (IS_FUNC_DEFINED(dev, i2c_read_byte_replace))
return dev->advance_func->i2c_read_byte_replace(dev);
i2c_smbus_data_t d;
if (mraa_i2c_smbus_access(dev->fh, I2C_SMBUS_READ, I2C_NOCMD, I2C_SMBUS_BYTE, &d) < 0) {
syslog(LOG_ERR, "i2c%i: read_byte: Access error: %s", dev->busnum, strerror(errno));
return -1;
}
return 0x0FF & d.byte;
}
int
mraa_i2c_read_byte_data(mraa_i2c_context dev, uint8_t command)
{
if (dev == NULL) {
syslog(LOG_ERR, "i2c: read_byte_data: context is invalid");
return -1;
}
if (IS_FUNC_DEFINED(dev, i2c_read_byte_data_replace))
return dev->advance_func->i2c_read_byte_data_replace(dev, command);
i2c_smbus_data_t d;
if (mraa_i2c_smbus_access(dev->fh, I2C_SMBUS_READ, command, I2C_SMBUS_BYTE_DATA, &d) < 0) {
syslog(LOG_ERR, "i2c%i: read_byte_data: Access error: %s", dev->busnum, strerror(errno));
return -1;
}
return 0x0FF & d.byte;
}
int
mraa_i2c_read_word_data(mraa_i2c_context dev, uint8_t command)
{
if (dev == NULL) {
syslog(LOG_ERR, "i2c: read_word_data: context is invalid");
return -1;
}
if (IS_FUNC_DEFINED(dev, i2c_read_word_data_replace))
return dev->advance_func->i2c_read_word_data_replace(dev, command);
i2c_smbus_data_t d;
if (mraa_i2c_smbus_access(dev->fh, I2C_SMBUS_READ, command, I2C_SMBUS_WORD_DATA, &d) < 0) {
syslog(LOG_ERR, "i2c%i: read_word_data: Access error: %s", dev->busnum, strerror(errno));
return -1;
}
return 0xFFFF & d.word;
}
int
mraa_i2c_read_bytes_data(mraa_i2c_context dev, uint8_t command, uint8_t* data, int length)
{
if (dev == NULL) {
syslog(LOG_ERR, "i2c: read_bytes_data: context is invalid");
return -1;
}
if (IS_FUNC_DEFINED(dev, i2c_read_bytes_data_replace))
return dev->advance_func->i2c_read_bytes_data_replace(dev, command, data, length);
struct i2c_rdwr_ioctl_data d;
struct i2c_msg m[2];
m[0].addr = dev->addr;
m[0].flags = 0x00;
m[0].len = 1;
m[0].buf = (char*) &command;
m[1].addr = dev->addr;
m[1].flags = I2C_M_RD;
m[1].len = length;
m[1].buf = (char*) data;
d.msgs = m;
d.nmsgs = 2;
int ret = ioctl(dev->fh, I2C_RDWR, &d);
if (ret < 0)
{
syslog(LOG_ERR, "i2c%i: read_bytes_data: Access error: %s", dev->busnum, strerror(errno));
return -1;
}
return length;
}
mraa_result_t
mraa_i2c_write(mraa_i2c_context dev, const uint8_t* data, int length)
{
if (dev == NULL) {
syslog(LOG_ERR, "i2c: write: context is invalid");
return MRAA_ERROR_INVALID_HANDLE;
}
if (IS_FUNC_DEFINED(dev, i2c_write_replace))
return dev->advance_func->i2c_write_replace(dev, data, length);
i2c_smbus_data_t d;
int i;
uint8_t command = data[0];
data = &data[1];
length = length - 1;
if (length > I2C_SMBUS_I2C_BLOCK_MAX) {
length = I2C_SMBUS_I2C_BLOCK_MAX;
}
for (i = 1; i <= length; i++) {
d.block[i] = data[i - 1];
}
d.block[0] = length;
if (mraa_i2c_smbus_access(dev->fh, I2C_SMBUS_WRITE, command, I2C_SMBUS_I2C_BLOCK_DATA, &d) < 0) {
syslog(LOG_ERR, "i2c%i: write: Access error: %s", dev->busnum, strerror(errno));
return MRAA_ERROR_UNSPECIFIED;
}
return MRAA_SUCCESS;
}
mraa_result_t
mraa_i2c_write_byte(mraa_i2c_context dev, const uint8_t data)
{
if (dev == NULL) {
syslog(LOG_ERR, "i2c: write_byte: context is invalid");
return MRAA_ERROR_INVALID_HANDLE;
}
if (IS_FUNC_DEFINED(dev, i2c_write_byte_replace)) {
return dev->advance_func->i2c_write_byte_replace(dev, data);
} else {
if (mraa_i2c_smbus_access(dev->fh, I2C_SMBUS_WRITE, data, I2C_SMBUS_BYTE, NULL) < 0) {
syslog(LOG_ERR, "i2c%i: write_byte: Access error: %s", dev->busnum, strerror(errno));
return MRAA_ERROR_UNSPECIFIED;
}
return MRAA_SUCCESS;
}
}
mraa_result_t
mraa_i2c_write_byte_data(mraa_i2c_context dev, const uint8_t data, const uint8_t command)
{
if (dev == NULL) {
syslog(LOG_ERR, "i2c: write_byte_data: context is invalid");
return MRAA_ERROR_INVALID_HANDLE;
}
if (IS_FUNC_DEFINED(dev, i2c_write_byte_data_replace))
return dev->advance_func->i2c_write_byte_data_replace(dev, data, command);
i2c_smbus_data_t d;
d.byte = data;
if (mraa_i2c_smbus_access(dev->fh, I2C_SMBUS_WRITE, command, I2C_SMBUS_BYTE_DATA, &d) < 0) {
syslog(LOG_ERR, "i2c%i: write_byte_data: Access error: %s", dev->busnum, strerror(errno));
return MRAA_ERROR_UNSPECIFIED;
}
return MRAA_SUCCESS;
}
mraa_result_t
mraa_i2c_write_word_data(mraa_i2c_context dev, const uint16_t data, const uint8_t command)
{
if (dev == NULL) {
syslog(LOG_ERR, "i2c: write_word_data: context is invalid");
return MRAA_ERROR_INVALID_HANDLE;
}
if (IS_FUNC_DEFINED(dev, i2c_write_word_data_replace))
return dev->advance_func->i2c_write_word_data_replace(dev, data, command);
i2c_smbus_data_t d;
d.word = data;
if (mraa_i2c_smbus_access(dev->fh, I2C_SMBUS_WRITE, command, I2C_SMBUS_WORD_DATA, &d) < 0) {
syslog(LOG_ERR, "i2c%i: write_word_data: Access error: %s", dev->busnum, strerror(errno));
return MRAA_ERROR_UNSPECIFIED;
}
return MRAA_SUCCESS;
}
mraa_result_t
mraa_i2c_address(mraa_i2c_context dev, uint8_t addr)
{
if (dev == NULL) {
syslog(LOG_ERR, "i2c: address: context is invalid");
return MRAA_ERROR_INVALID_HANDLE;
}
dev->addr = (int) addr;
if (IS_FUNC_DEFINED(dev, i2c_address_replace)) {
return dev->advance_func->i2c_address_replace(dev, addr);
} else {
if (ioctl(dev->fh, I2C_SLAVE_FORCE, addr) < 0) {
syslog(LOG_ERR, "i2c%i: address: Failed to set slave address %d: %s", dev->busnum, addr, strerror(errno));
return MRAA_ERROR_UNSPECIFIED;
}
return MRAA_SUCCESS;
}
}
mraa_result_t
mraa_i2c_stop(mraa_i2c_context dev)
{
if (dev == NULL) {
syslog(LOG_ERR, "i2c: stop: context is invalid");
return MRAA_ERROR_INVALID_HANDLE;
}
if (IS_FUNC_DEFINED(dev, i2c_stop_replace)) {
return dev->advance_func->i2c_stop_replace(dev);
}
close(dev->fh);
free(dev);
return MRAA_SUCCESS;
}
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