zephyr/drivers/sensor/max30101/max30101.c

244 lines
6.5 KiB
C

/*
* Copyright (c) 2017, NXP
*
* SPDX-License-Identifier: Apache-2.0
*/
#include "max30101.h"
static int max30101_sample_fetch(struct device *dev, enum sensor_channel chan)
{
struct max30101_data *data = dev->driver_data;
u8_t buffer[MAX30101_MAX_BYTES_PER_SAMPLE];
u32_t fifo_data;
int fifo_chan;
int num_bytes;
int i;
/* Read all the active channels for one sample */
num_bytes = data->num_channels * MAX30101_BYTES_PER_CHANNEL;
if (i2c_burst_read(data->i2c, MAX30101_I2C_ADDRESS,
MAX30101_REG_FIFO_DATA, buffer, num_bytes)) {
SYS_LOG_ERR("Could not fetch sample");
return -EIO;
}
fifo_chan = 0;
for (i = 0; i < num_bytes; i += 3) {
/* Each channel is 18-bits */
fifo_data = (buffer[i] << 16) | (buffer[i + 1] << 8) |
(buffer[i + 2]);
fifo_data &= MAX30101_FIFO_DATA_MASK;
/* Save the raw data */
data->raw[fifo_chan++] = fifo_data;
}
return 0;
}
static int max30101_channel_get(struct device *dev, enum sensor_channel chan,
struct sensor_value *val)
{
struct max30101_data *data = dev->driver_data;
enum max30101_led_channel led_chan;
int fifo_chan;
switch (chan) {
case SENSOR_CHAN_RED:
led_chan = MAX30101_LED_CHANNEL_RED;
break;
case SENSOR_CHAN_IR:
led_chan = MAX30101_LED_CHANNEL_IR;
break;
case SENSOR_CHAN_GREEN:
led_chan = MAX30101_LED_CHANNEL_GREEN;
break;
default:
SYS_LOG_ERR("Unsupported sensor channel");
return -ENOTSUP;
}
/* Check if the led channel is active by looking up the associated fifo
* channel. If the fifo channel isn't valid, then the led channel
* isn't active.
*/
fifo_chan = data->map[led_chan];
if (fifo_chan >= MAX30101_MAX_NUM_CHANNELS) {
SYS_LOG_ERR("Inactive sensor channel");
return -ENOTSUP;
}
/* TODO: Scale the raw data to standard units */
val->val1 = data->raw[fifo_chan];
val->val2 = 0;
return 0;
}
static const struct sensor_driver_api max30101_driver_api = {
.sample_fetch = max30101_sample_fetch,
.channel_get = max30101_channel_get,
};
static int max30101_init(struct device *dev)
{
const struct max30101_config *config = dev->config->config_info;
struct max30101_data *data = dev->driver_data;
u8_t part_id;
u8_t mode_cfg;
u32_t led_chan;
int fifo_chan;
/* Get the I2C device */
data->i2c = device_get_binding(CONFIG_MAX30101_I2C_NAME);
if (!data->i2c) {
SYS_LOG_ERR("Could not find I2C device");
return -EINVAL;
}
/* Check the part id to make sure this is MAX30101 */
if (i2c_reg_read_byte(data->i2c, MAX30101_I2C_ADDRESS,
MAX30101_REG_PART_ID, &part_id)) {
SYS_LOG_ERR("Could not get Part ID");
return -EIO;
}
if (part_id != MAX30101_PART_ID) {
SYS_LOG_ERR("Got Part ID 0x%02x, expected 0x%02x",
part_id, MAX30101_PART_ID);
return -EIO;
}
/* Reset the sensor */
if (i2c_reg_write_byte(data->i2c, MAX30101_I2C_ADDRESS,
MAX30101_REG_MODE_CFG,
MAX30101_MODE_CFG_RESET_MASK)) {
return -EIO;
}
/* Wait for reset to be cleared */
do {
if (i2c_reg_read_byte(data->i2c, MAX30101_I2C_ADDRESS,
MAX30101_REG_MODE_CFG, &mode_cfg)) {
SYS_LOG_ERR("Could read mode cfg after reset");
return -EIO;
}
} while (mode_cfg & MAX30101_MODE_CFG_RESET_MASK);
/* Write the FIFO configuration register */
if (i2c_reg_write_byte(data->i2c, MAX30101_I2C_ADDRESS,
MAX30101_REG_FIFO_CFG, config->fifo)) {
return -EIO;
}
/* Write the mode configuration register */
if (i2c_reg_write_byte(data->i2c, MAX30101_I2C_ADDRESS,
MAX30101_REG_MODE_CFG, config->mode)) {
return -EIO;
}
/* Write the SpO2 configuration register */
if (i2c_reg_write_byte(data->i2c, MAX30101_I2C_ADDRESS,
MAX30101_REG_SPO2_CFG, config->spo2)) {
return -EIO;
}
/* Write the LED pulse amplitude registers */
if (i2c_reg_write_byte(data->i2c, MAX30101_I2C_ADDRESS,
MAX30101_REG_LED1_PA, config->led_pa[0])) {
return -EIO;
}
if (i2c_reg_write_byte(data->i2c, MAX30101_I2C_ADDRESS,
MAX30101_REG_LED2_PA, config->led_pa[1])) {
return -EIO;
}
if (i2c_reg_write_byte(data->i2c, MAX30101_I2C_ADDRESS,
MAX30101_REG_LED3_PA, config->led_pa[2])) {
return -EIO;
}
#ifdef CONFIG_MAX30101_MULTI_LED_MODE
u8_t multi_led[2];
/* Write the multi-LED mode control registers */
multi_led[0] = (config->slot[1] << 4) | (config->slot[0]);
multi_led[1] = (config->slot[3] << 4) | (config->slot[2]);
if (i2c_reg_write_byte(data->i2c, MAX30101_I2C_ADDRESS,
MAX30101_REG_MULTI_LED, multi_led[0])) {
return -EIO;
}
if (i2c_reg_write_byte(data->i2c, MAX30101_I2C_ADDRESS,
MAX30101_REG_MULTI_LED + 1, multi_led[1])) {
return -EIO;
}
#endif
/* Initialize the channel map and active channel count */
data->num_channels = 0;
for (led_chan = 0; led_chan < MAX30101_MAX_NUM_CHANNELS; led_chan++) {
data->map[led_chan] = MAX30101_MAX_NUM_CHANNELS;
}
/* Count the number of active channels and build a map that translates
* the LED channel number (red/ir/green) to the fifo channel number.
*/
for (fifo_chan = 0; fifo_chan < MAX30101_MAX_NUM_CHANNELS;
fifo_chan++) {
led_chan = (config->slot[fifo_chan] & MAX30101_SLOT_LED_MASK)-1;
if (led_chan < MAX30101_MAX_NUM_CHANNELS) {
data->map[led_chan] = fifo_chan;
data->num_channels++;
}
}
return 0;
}
static struct max30101_config max30101_config = {
.fifo = (CONFIG_MAX30101_SMP_AVE << MAX30101_FIFO_CFG_SMP_AVE_SHIFT) |
#ifdef CONFIG_MAX30101_FIFO_ROLLOVER_EN
MAX30101_FIFO_CFG_ROLLOVER_EN_MASK |
#endif
(CONFIG_MAX30101_FIFO_A_FULL <<
MAX30101_FIFO_CFG_FIFO_FULL_SHIFT),
#if defined(CONFIG_MAX30101_HEART_RATE_MODE)
.mode = MAX30101_MODE_HEART_RATE,
.slot[0] = MAX30101_SLOT_RED_LED1_PA,
.slot[1] = MAX30101_SLOT_DISABLED,
.slot[2] = MAX30101_SLOT_DISABLED,
.slot[3] = MAX30101_SLOT_DISABLED,
#elif defined(CONFIG_MAX30101_SPO2_MODE)
.mode = MAX30101_MODE_SPO2,
.slot[0] = MAX30101_SLOT_RED_LED1_PA,
.slot[1] = MAX30101_SLOT_IR_LED2_PA,
.slot[2] = MAX30101_SLOT_DISABLED,
.slot[3] = MAX30101_SLOT_DISABLED,
#else
.mode = MAX30101_MODE_MULTI_LED,
.slot[0] = CONFIG_MAX30101_SLOT1,
.slot[1] = CONFIG_MAX30101_SLOT2,
.slot[2] = CONFIG_MAX30101_SLOT3,
.slot[3] = CONFIG_MAX30101_SLOT4,
#endif
.spo2 = (CONFIG_MAX30101_ADC_RGE << MAX30101_SPO2_ADC_RGE_SHIFT) |
(CONFIG_MAX30101_SR << MAX30101_SPO2_SR_SHIFT) |
(MAX30101_PW_18BITS << MAX30101_SPO2_PW_SHIFT),
.led_pa[0] = CONFIG_MAX30101_LED1_PA,
.led_pa[1] = CONFIG_MAX30101_LED2_PA,
.led_pa[2] = CONFIG_MAX30101_LED3_PA,
};
static struct max30101_data max30101_data;
DEVICE_AND_API_INIT(max30101, CONFIG_MAX30101_NAME, max30101_init,
&max30101_data, &max30101_config,
POST_KERNEL, CONFIG_SENSOR_INIT_PRIORITY,
&max30101_driver_api);