zephyr/drivers/sensor/tdk/icm42688/icm42688_emul.c

420 lines
11 KiB
C

/*
* Copyright (c) 2023 Google LLC
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT invensense_icm42688
#include <zephyr/device.h>
#include <zephyr/drivers/emul.h>
#include <zephyr/drivers/emul_sensor.h>
#include <zephyr/drivers/spi.h>
#include <zephyr/drivers/spi_emul.h>
#include <zephyr/logging/log.h>
#include <icm42688_reg.h>
LOG_MODULE_DECLARE(ICM42688, CONFIG_SENSOR_LOG_LEVEL);
#define NUM_REGS (UINT8_MAX >> 1)
struct icm42688_emul_data {
uint8_t reg[NUM_REGS];
};
struct icm42688_emul_cfg {
};
void icm42688_emul_set_reg(const struct emul *target, uint8_t reg_addr, const uint8_t *val,
size_t count)
{
struct icm42688_emul_data *data = target->data;
__ASSERT_NO_MSG(reg_addr + count < NUM_REGS);
memcpy(data->reg + reg_addr, val, count);
}
void icm42688_emul_get_reg(const struct emul *target, uint8_t reg_addr, uint8_t *val, size_t count)
{
struct icm42688_emul_data *data = target->data;
__ASSERT_NO_MSG(reg_addr + count < NUM_REGS);
memcpy(val, data->reg + reg_addr, count);
}
static void icm42688_emul_handle_write(const struct emul *target, uint8_t regn, uint8_t value)
{
struct icm42688_emul_data *data = target->data;
switch (regn) {
case REG_DEVICE_CONFIG:
if (FIELD_GET(BIT_SOFT_RESET, value) == 1) {
/* Perform a soft reset */
memset(data->reg, 0, NUM_REGS);
/* Initialized the who-am-i register */
data->reg[REG_WHO_AM_I] = WHO_AM_I_ICM42688;
/* Set the bit for the reset being done */
data->reg[REG_INT_STATUS] |= BIT_INT_STATUS_RESET_DONE;
}
break;
}
}
static int icm42688_emul_io_spi(const struct emul *target, const struct spi_config *config,
const struct spi_buf_set *tx_bufs,
const struct spi_buf_set *rx_bufs)
{
struct icm42688_emul_data *data = target->data;
const struct spi_buf *tx, *rx;
uint8_t regn;
bool is_read;
ARG_UNUSED(config);
__ASSERT_NO_MSG(tx_bufs != NULL);
tx = tx_bufs->buffers;
__ASSERT_NO_MSG(tx != NULL);
__ASSERT_NO_MSG(tx->len > 0);
regn = *(uint8_t *)tx->buf;
is_read = FIELD_GET(REG_SPI_READ_BIT, regn);
regn &= GENMASK(6, 0);
if (is_read) {
__ASSERT_NO_MSG(rx_bufs != NULL);
__ASSERT_NO_MSG(rx_bufs->count > 1);
rx = &rx_bufs->buffers[1];
__ASSERT_NO_MSG(rx->buf != NULL);
__ASSERT_NO_MSG(rx->len > 0);
for (uint16_t i = 0; i < rx->len; ++i) {
((uint8_t *)rx->buf)[i] = data->reg[regn + i];
}
} else {
/* Writing to regn */
uint8_t value;
__ASSERT_NO_MSG(tx_bufs->count > 1);
tx = &tx_bufs->buffers[1];
__ASSERT_NO_MSG(tx->len > 0);
value = ((uint8_t *)tx->buf)[0];
icm42688_emul_handle_write(target, regn, value);
}
return 0;
}
static int icm42688_emul_init(const struct emul *target, const struct device *parent)
{
struct icm42688_emul_data *data = target->data;
/* Initialized the who-am-i register */
data->reg[REG_WHO_AM_I] = WHO_AM_I_ICM42688;
return 0;
}
static const struct spi_emul_api icm42688_emul_spi_api = {
.io = icm42688_emul_io_spi,
};
#define Q31_SCALE ((int64_t)INT32_MAX + 1)
/**
* @brief Get current full-scale range in g's based on register config, along with corresponding
* sensitivity and shift. See datasheet section 3.2, table 2.
*/
static void icm42688_emul_get_accel_settings(const struct emul *target, int *fs_g, int *sensitivity,
int8_t *shift)
{
uint8_t reg;
int sensitivity_out, fs_g_out;
int8_t shift_out;
icm42688_emul_get_reg(target, REG_ACCEL_CONFIG0, &reg, 1);
switch ((reg & MASK_ACCEL_UI_FS_SEL) >> 5) {
case BIT_ACCEL_UI_FS_16:
fs_g_out = 16;
sensitivity_out = 2048;
/* shift is based on `fs_g * 9.8` since the final numbers will be in SI units of
* m/s^2, not g's
*/
shift_out = 8;
break;
case BIT_ACCEL_UI_FS_8:
fs_g_out = 8;
sensitivity_out = 4096;
shift_out = 7;
break;
case BIT_ACCEL_UI_FS_4:
fs_g_out = 4;
sensitivity_out = 8192;
shift_out = 6;
break;
case BIT_ACCEL_UI_FS_2:
fs_g_out = 2;
sensitivity_out = 16384;
shift_out = 5;
break;
default:
__ASSERT_UNREACHABLE;
}
if (fs_g) {
*fs_g = fs_g_out;
}
if (sensitivity) {
*sensitivity = sensitivity_out;
}
if (shift) {
*shift = shift_out;
}
}
/**
* @brief Helper function for calculating accelerometer ranges. Considers the current full-scale
* register config (i.e. +/-2g, +/-4g, etc...)
*/
static void icm42688_emul_get_accel_ranges(const struct emul *target, q31_t *lower, q31_t *upper,
q31_t *epsilon, int8_t *shift)
{
int fs_g;
int sensitivity;
icm42688_emul_get_accel_settings(target, &fs_g, &sensitivity, shift);
/* Epsilon is equal to 1.5 bit-counts worth of error. */
*epsilon = (3 * SENSOR_G * Q31_SCALE / sensitivity / 1000000LL / 2) >> *shift;
*upper = (fs_g * SENSOR_G * Q31_SCALE / 1000000LL) >> *shift;
*lower = -*upper;
}
/**
* @brief Get current full-scale gyro range in milli-degrees per second based on register config,
* along with corresponding sensitivity and shift. See datasheet section 3.1, table 1.
*/
static void icm42688_emul_get_gyro_settings(const struct emul *target, int *fs_mdps,
int *sensitivity, int8_t *shift)
{
uint8_t reg;
int sensitivity_out, fs_mdps_out;
int8_t shift_out;
icm42688_emul_get_reg(target, REG_GYRO_CONFIG0, &reg, 1);
switch ((reg & MASK_GYRO_UI_FS_SEL) >> 5) {
case BIT_GYRO_UI_FS_2000:
/* Milli-degrees per second */
fs_mdps_out = 2000000;
/* 10x LSBs/deg/s */
sensitivity_out = 164;
/* Shifts are based on rad/s: `(fs_mdps * pi / 180 / 1000)` */
shift_out = 6; /* +/- 34.90659 */
break;
case BIT_GYRO_UI_FS_1000:
fs_mdps_out = 1000000;
sensitivity_out = 328;
shift_out = 5; /* +/- 17.44444 */
break;
case BIT_GYRO_UI_FS_500:
fs_mdps_out = 500000;
sensitivity_out = 655;
shift_out = 4; /* +/- 8.72222 */
break;
case BIT_GYRO_UI_FS_250:
fs_mdps_out = 250000;
sensitivity_out = 1310;
shift_out = 3; /* +/- 4.36111 */
break;
case BIT_GYRO_UI_FS_125:
fs_mdps_out = 125000;
sensitivity_out = 2620;
shift_out = 2; /* +/- 2.18055 */
break;
case BIT_GYRO_UI_FS_62_5:
fs_mdps_out = 62500;
sensitivity_out = 5243;
shift_out = 1; /* +/- 1.09027 */
break;
case BIT_GYRO_UI_FS_31_25:
fs_mdps_out = 31250;
sensitivity_out = 10486;
shift_out = 0; /* +/- 0.54513 */
break;
case BIT_GYRO_UI_FS_15_625:
fs_mdps_out = 15625;
sensitivity_out = 20972;
shift_out = -1; /* +/- 0.27256 */
break;
default:
__ASSERT_UNREACHABLE;
}
if (fs_mdps) {
*fs_mdps = fs_mdps_out;
}
if (sensitivity) {
*sensitivity = sensitivity_out;
}
if (shift) {
*shift = shift_out;
}
}
/**
* @brief Helper function for calculating gyroscope ranges. Considers the current full-scale
* register config
*/
static void icm42688_emul_get_gyro_ranges(const struct emul *target, q31_t *lower, q31_t *upper,
q31_t *epsilon, int8_t *shift)
{
/* millidegrees/second */
int fs_mdps;
/* 10x LSBs per degrees/second*/
int sensitivity;
icm42688_emul_get_gyro_settings(target, &fs_mdps, &sensitivity, shift);
/* Reduce the actual range of gyroscope values. Some full-scale ranges actually exceed the
* size of an int16 by a small margin. For example, FS_SEL=0 has a +/-2000 deg/s range with
* 16.4 bits/deg/s sensitivity (Section 3.1, Table 1). This works out to register values of
* +/-2000 * 16.4 = +/-32800. This will cause the expected value to get clipped when
* setting the register and throw off the actual reading. Therefore, scale down the range
* to 99% to avoid the top and bottom edges.
*/
fs_mdps *= 0.99;
/* Epsilon is equal to 1.5 bit-counts worth of error. */
*epsilon = (3 * SENSOR_PI * Q31_SCALE * 10LL / 1000000LL / 180LL / sensitivity / 2LL) >>
*shift;
*upper = (((fs_mdps * SENSOR_PI / 1000000LL) * Q31_SCALE) / 1000LL / 180LL) >> *shift;
*lower = -*upper;
}
static int icm42688_emul_backend_get_sample_range(const struct emul *target,
struct sensor_chan_spec ch, q31_t *lower,
q31_t *upper, q31_t *epsilon, int8_t *shift)
{
if (!lower || !upper || !epsilon || !shift) {
return -EINVAL;
}
switch (ch.chan_type) {
case SENSOR_CHAN_DIE_TEMP:
/* degrees C = ([16-bit signed temp_data register] / 132.48) + 25 */
*shift = 9;
*lower = (int64_t)(-222.342995169 * Q31_SCALE) >> *shift;
*upper = (int64_t)(272.33544686 * Q31_SCALE) >> *shift;
*epsilon = (int64_t)(0.0076 * Q31_SCALE) >> *shift;
break;
case SENSOR_CHAN_ACCEL_X:
case SENSOR_CHAN_ACCEL_Y:
case SENSOR_CHAN_ACCEL_Z:
icm42688_emul_get_accel_ranges(target, lower, upper, epsilon, shift);
break;
case SENSOR_CHAN_GYRO_X:
case SENSOR_CHAN_GYRO_Y:
case SENSOR_CHAN_GYRO_Z:
icm42688_emul_get_gyro_ranges(target, lower, upper, epsilon, shift);
break;
default:
return -ENOTSUP;
}
return 0;
}
static int icm42688_emul_backend_set_channel(const struct emul *target, struct sensor_chan_spec ch,
const q31_t *value, int8_t shift)
{
if (!target || !target->data) {
return -EINVAL;
}
struct icm42688_emul_data *data = target->data;
int sensitivity;
uint8_t reg_addr;
int32_t reg_val;
int64_t value_unshifted =
shift < 0 ? ((int64_t)*value >> -shift) : ((int64_t)*value << shift);
switch (ch.chan_type) {
case SENSOR_CHAN_DIE_TEMP:
reg_addr = REG_TEMP_DATA1;
reg_val = ((value_unshifted - (25 * Q31_SCALE)) * 13248) / (100 * Q31_SCALE);
break;
case SENSOR_CHAN_ACCEL_X:
case SENSOR_CHAN_ACCEL_Y:
case SENSOR_CHAN_ACCEL_Z:
switch (ch.chan_type) {
case SENSOR_CHAN_ACCEL_X:
reg_addr = REG_ACCEL_DATA_X1;
break;
case SENSOR_CHAN_ACCEL_Y:
reg_addr = REG_ACCEL_DATA_Y1;
break;
case SENSOR_CHAN_ACCEL_Z:
reg_addr = REG_ACCEL_DATA_Z1;
break;
default:
__ASSERT_UNREACHABLE;
}
icm42688_emul_get_accel_settings(target, NULL, &sensitivity, NULL);
reg_val = ((value_unshifted * sensitivity / Q31_SCALE) * 1000000LL) / SENSOR_G;
break;
case SENSOR_CHAN_GYRO_X:
case SENSOR_CHAN_GYRO_Y:
case SENSOR_CHAN_GYRO_Z:
switch (ch.chan_type) {
case SENSOR_CHAN_GYRO_X:
reg_addr = REG_GYRO_DATA_X1;
break;
case SENSOR_CHAN_GYRO_Y:
reg_addr = REG_GYRO_DATA_Y1;
break;
case SENSOR_CHAN_GYRO_Z:
reg_addr = REG_GYRO_DATA_Z1;
break;
default:
__ASSERT_UNREACHABLE;
}
icm42688_emul_get_gyro_settings(target, NULL, &sensitivity, NULL);
reg_val =
CLAMP((((value_unshifted * sensitivity * 180LL) / Q31_SCALE) * 1000000LL) /
SENSOR_PI / 10LL,
INT16_MIN, INT16_MAX);
break;
default:
return -ENOTSUP;
}
data->reg[reg_addr] = (reg_val >> 8) & 0xFF;
data->reg[reg_addr + 1] = reg_val & 0xFF;
/* Set data ready flag */
data->reg[REG_INT_STATUS] |= BIT_INT_STATUS_DATA_RDY;
return 0;
}
static const struct emul_sensor_driver_api icm42688_emul_sensor_driver_api = {
.set_channel = icm42688_emul_backend_set_channel,
.get_sample_range = icm42688_emul_backend_get_sample_range,
};
#define ICM42688_EMUL_DEFINE(n, api) \
EMUL_DT_INST_DEFINE(n, icm42688_emul_init, &icm42688_emul_data_##n, \
&icm42688_emul_cfg_##n, &api, &icm42688_emul_sensor_driver_api)
#define ICM42688_EMUL_SPI(n) \
static struct icm42688_emul_data icm42688_emul_data_##n; \
static const struct icm42688_emul_cfg icm42688_emul_cfg_##n; \
ICM42688_EMUL_DEFINE(n, icm42688_emul_spi_api)
DT_INST_FOREACH_STATUS_OKAY(ICM42688_EMUL_SPI)