/* Bosch BMG160 gyro driver
*
* Copyright (c) 2016 Intel Corporation
*
* 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.
*
* Datasheet:
* http://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMG160-DS000-09.pdf
*/
#include <init.h>
#include <sensor.h>
#include <misc/byteorder.h>
#include <nanokernel.h>
#include "sensor_bmg160.h"
struct bmg160_device_data bmg160_data;
static inline int bmg160_bus_config(struct device *dev)
{
struct bmg160_device_config *dev_cfg = dev->config->config_info;
struct bmg160_device_data *bmg160 = dev->driver_data;
union dev_config i2c_cfg;
i2c_cfg.raw = 0;
i2c_cfg.bits.is_master_device = 1;
i2c_cfg.bits.speed = dev_cfg->i2c_speed;
return i2c_configure(bmg160->i2c, i2c_cfg.raw);
}
int bmg160_read(struct device *dev, uint8_t reg_addr, uint8_t *data,
uint8_t len)
{
struct bmg160_device_config *dev_cfg = dev->config->config_info;
struct bmg160_device_data *bmg160 = dev->driver_data;
int ret = 0;
bmg160_bus_config(dev);
nano_sem_take(&bmg160->sem, TICKS_UNLIMITED);
if (i2c_burst_read(bmg160->i2c, dev_cfg->i2c_addr,
reg_addr, data, len) < 0) {
ret = -EIO;
}
nano_sem_give(&bmg160->sem);
return ret;
}
int bmg160_read_byte(struct device *dev, uint8_t reg_addr, uint8_t *byte)
{
return bmg160_read(dev, reg_addr, byte, 1);
}
static int bmg160_write(struct device *dev, uint8_t reg_addr, uint8_t *data,
uint8_t len)
{
struct bmg160_device_config *dev_cfg = dev->config->config_info;
struct bmg160_device_data *bmg160 = dev->driver_data;
int ret = 0;
bmg160_bus_config(dev);
nano_sem_take(&bmg160->sem, TICKS_UNLIMITED);
if (i2c_burst_write(bmg160->i2c, dev_cfg->i2c_addr,
reg_addr, data, len) < 0) {
ret = -EIO;
}
nano_sem_give(&bmg160->sem);
return ret;
}
int bmg160_write_byte(struct device *dev, uint8_t reg_addr, uint8_t byte)
{
return bmg160_write(dev, reg_addr, &byte, 1);
}
int bmg160_update_byte(struct device *dev, uint8_t reg_addr, uint8_t mask,
uint8_t value)
{
struct bmg160_device_config *dev_cfg = dev->config->config_info;
struct bmg160_device_data *bmg160 = dev->driver_data;
int ret = 0;
bmg160_bus_config(dev);
nano_sem_take(&bmg160->sem, TICKS_UNLIMITED);
if (i2c_reg_update_byte(bmg160->i2c, dev_cfg->i2c_addr,
reg_addr, mask, value) < 0) {
ret = -EIO;
}
nano_sem_give(&bmg160->sem);
return ret;
}
/* Allowed range values, in degrees/sec. */
static const int16_t bmg160_gyro_range_map[] = {2000, 1000, 500, 250, 125};
#define BMG160_GYRO_RANGE_MAP_SIZE ARRAY_SIZE(bmg160_gyro_range_map)
/* Allowed sampling frequencies, in Hz */
static const int16_t bmg160_sampling_freq_map[] = {2000, 1000, 400, 200, 100};
#define BMG160_SAMPLING_FREQ_MAP_SIZE ARRAY_SIZE(bmg160_sampling_freq_map)
static int bmg160_is_val_valid(int16_t val, const int16_t *val_map,
uint16_t map_size)
{
int i;
for (i = 0; i < map_size; i++) {
if (val == val_map[i]) {
return i;
}
}
return -1;
}
static int bmg160_attr_set(struct device *dev, enum sensor_channel chan,
enum sensor_attribute attr,
const struct sensor_value *val)
{
struct bmg160_device_data *bmg160 = dev->driver_data;
int idx;
uint16_t range_dps;
if (chan != SENSOR_CHAN_GYRO_ANY) {
return -ENOTSUP;
}
switch (attr) {
case SENSOR_ATTR_FULL_SCALE:
if (val->type != SENSOR_VALUE_TYPE_INT_PLUS_MICRO) {
return -ENOTSUP;
}
range_dps = sensor_rad_to_degrees(val);
idx = bmg160_is_val_valid(range_dps,
bmg160_gyro_range_map,
BMG160_GYRO_RANGE_MAP_SIZE);
if (idx < 0) {
return -ENOTSUP;
}
if (bmg160_write_byte(dev, BMG160_REG_RANGE, idx) < 0) {
return -EIO;
}
bmg160->scale = BMG160_RANGE_TO_SCALE(range_dps);
return 0;
case SENSOR_ATTR_SAMPLING_FREQUENCY:
if (val->type != SENSOR_VALUE_TYPE_INT) {
return -ENOTSUP;
}
idx = bmg160_is_val_valid(val->val1,
bmg160_sampling_freq_map,
BMG160_SAMPLING_FREQ_MAP_SIZE);
if (idx < 0) {
return -ENOTSUP;
}
/*
* The sampling frequencies values start at 1, i.e. a
* sampling frequency of 2000Hz translates to BW value
* of 1. Hence the 1 added to the index received.
*/
if (bmg160_write_byte(dev, BMG160_REG_BW, idx + 1) < 0) {
return -EIO;
}
return 0;
#ifdef CONFIG_BMG160_TRIGGER
case SENSOR_ATTR_SLOPE_TH:
case SENSOR_ATTR_SLOPE_DUR:
return bmg160_slope_config(dev, attr, val);
#endif
default:
return -ENOTSUP;
}
}
static int bmg160_sample_fetch(struct device *dev, enum sensor_channel chan)
{
struct bmg160_device_data *bmg160 = dev->driver_data;
union {
uint8_t raw[7];
struct {
uint16_t x_axis;
uint16_t y_axis;
uint16_t z_axis;
uint8_t temp;
};
} buf __aligned(2);
/* do a burst read, to fetch all axis data */
if (bmg160_read(dev, BMG160_REG_RATE_X, buf.raw, sizeof(buf)) < 0) {
return -EIO;
}
bmg160->raw_gyro_xyz[0] = sys_le16_to_cpu(buf.x_axis);
bmg160->raw_gyro_xyz[1] = sys_le16_to_cpu(buf.y_axis);
bmg160->raw_gyro_xyz[2] = sys_le16_to_cpu(buf.z_axis);
bmg160->raw_temp = buf.temp;
return 0;
}
static void bmg160_to_fixed_point(struct bmg160_device_data *bmg160,
enum sensor_channel chan, int16_t raw,
struct sensor_value *val)
{
val->type = SENSOR_VALUE_TYPE_INT_PLUS_MICRO;
if (chan == SENSOR_CHAN_TEMP) {
val->val1 = 23 + (raw / 2);
val->val2 = (raw % 2) * 500000;
} else {
int32_t converted_val = raw * bmg160->scale;
val->val1 = converted_val / 1000000;
val->val2 = converted_val % 1000000;
}
}
static int bmg160_channel_get(struct device *dev, enum sensor_channel chan,
struct sensor_value *val)
{
struct bmg160_device_data *bmg160 = dev->driver_data;
int16_t raw_val;
int i;
switch (chan) {
case SENSOR_CHAN_GYRO_X:
case SENSOR_CHAN_GYRO_Y:
case SENSOR_CHAN_GYRO_Z:
raw_val = bmg160->raw_gyro_xyz[chan - SENSOR_CHAN_GYRO_X];
bmg160_to_fixed_point(bmg160, chan, raw_val, val);
return 0;
case SENSOR_CHAN_GYRO_ANY:
/* return all channel values, in one read */
for (i = 0; i < 3; i++, val++) {
raw_val = bmg160->raw_gyro_xyz[i];
bmg160_to_fixed_point(bmg160, chan, raw_val, val);
}
return 0;
case SENSOR_CHAN_TEMP:
bmg160_to_fixed_point(bmg160, chan, bmg160->raw_temp, val);
return 0;
default:
return -ENOTSUP;
}
}
struct sensor_driver_api bmg160_api = {
.attr_set = bmg160_attr_set,
#ifdef CONFIG_BMG160_TRIGGER
.trigger_set = bmg160_trigger_set,
#endif
.sample_fetch = bmg160_sample_fetch,
.channel_get = bmg160_channel_get,
};
int bmg160_init(struct device *dev)
{
struct bmg160_device_config *cfg = dev->config->config_info;
struct bmg160_device_data *bmg160 = dev->driver_data;
uint8_t chip_id = 0;
uint16_t range_dps;
bmg160->i2c = device_get_binding((char *)cfg->i2c_port);
if (!bmg160->i2c) {
SYS_LOG_DBG("I2C master controller not found!");
return -EINVAL;
}
nano_sem_init(&bmg160->sem);
nano_sem_give(&bmg160->sem);
if (bmg160_read_byte(dev, BMG160_REG_CHIPID, &chip_id) < 0) {
SYS_LOG_DBG("Failed to read chip id.");
return -EIO;
}
if (chip_id != BMG160_CHIP_ID) {
SYS_LOG_DBG("Unsupported chip detected (0x%x)!", chip_id);
return -ENODEV;
}
/* reset the chip */
bmg160_write_byte(dev, BMG160_REG_BGW_SOFTRESET, BMG160_RESET);
sys_thread_busy_wait(1000); /* wait for the chip to come up */
if (bmg160_write_byte(dev, BMG160_REG_RANGE,
BMG160_DEFAULT_RANGE) < 0) {
SYS_LOG_DBG("Failed to set range.");
return -EIO;
}
range_dps = bmg160_gyro_range_map[BMG160_DEFAULT_RANGE];
bmg160->scale = BMG160_RANGE_TO_SCALE(range_dps);
if (bmg160_write_byte(dev, BMG160_REG_BW, BMG160_DEFAULT_ODR) < 0) {
SYS_LOG_DBG("Failed to set sampling frequency.");
return -EIO;
}
/* disable interrupts */
if (bmg160_write_byte(dev, BMG160_REG_INT_EN0, 0) < 0) {
SYS_LOG_DBG("Failed to disable all interrupts.");
return -EIO;
}
#ifdef CONFIG_BMG160_TRIGGER
bmg160_trigger_init(dev);
#endif
dev->driver_api = &bmg160_api;
return 0;
}
struct bmg160_device_config bmg160_config = {
.i2c_port = CONFIG_BMG160_I2C_PORT_NAME,
.i2c_addr = CONFIG_BMG160_I2C_ADDR,
.i2c_speed = BMG160_BUS_SPEED,
#ifdef CONFIG_BMG160_TRIGGER
.gpio_port = CONFIG_BMG160_GPIO_PORT_NAME,
.int_pin = CONFIG_BMG160_INT_PIN,
#endif
};
DEVICE_INIT(bmg160, CONFIG_BMG160_DRV_NAME, bmg160_init, &bmg160_data,
&bmg160_config, SECONDARY, CONFIG_BMG160_INIT_PRIORITY);