// SPDX-License-Identifier: GPL-2.0-only
/*
* ADXL313 3-Axis Digital Accelerometer
*
* Copyright (c) 2021 Lucas Stankus <lucas.p.stankus@gmail.com>
*
* Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ADXL313.pdf
*/
#include <linux/bitfield.h>
#include <linux/iio/iio.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include "adxl313.h"
static const struct regmap_range adxl313_readable_reg_range[] = {
regmap_reg_range(ADXL313_REG_DEVID0, ADXL313_REG_XID),
regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_FIFO_STATUS),
};
const struct regmap_access_table adxl313_readable_regs_table = {
.yes_ranges = adxl313_readable_reg_range,
.n_yes_ranges = ARRAY_SIZE(adxl313_readable_reg_range),
};
EXPORT_SYMBOL_NS_GPL(adxl313_readable_regs_table, IIO_ADXL313);
static const struct regmap_range adxl313_writable_reg_range[] = {
regmap_reg_range(ADXL313_REG_SOFT_RESET, ADXL313_REG_SOFT_RESET),
regmap_reg_range(ADXL313_REG_OFS_AXIS(0), ADXL313_REG_OFS_AXIS(2)),
regmap_reg_range(ADXL313_REG_THRESH_ACT, ADXL313_REG_ACT_INACT_CTL),
regmap_reg_range(ADXL313_REG_BW_RATE, ADXL313_REG_INT_MAP),
regmap_reg_range(ADXL313_REG_DATA_FORMAT, ADXL313_REG_DATA_FORMAT),
regmap_reg_range(ADXL313_REG_FIFO_CTL, ADXL313_REG_FIFO_CTL),
};
const struct regmap_access_table adxl313_writable_regs_table = {
.yes_ranges = adxl313_writable_reg_range,
.n_yes_ranges = ARRAY_SIZE(adxl313_writable_reg_range),
};
EXPORT_SYMBOL_NS_GPL(adxl313_writable_regs_table, IIO_ADXL313);
struct adxl313_data {
struct regmap *regmap;
struct mutex lock; /* lock to protect transf_buf */
__le16 transf_buf __aligned(IIO_DMA_MINALIGN);
};
static const int adxl313_odr_freqs[][2] = {
[0] = { 6, 250000 },
[1] = { 12, 500000 },
[2] = { 25, 0 },
[3] = { 50, 0 },
[4] = { 100, 0 },
[5] = { 200, 0 },
[6] = { 400, 0 },
[7] = { 800, 0 },
[8] = { 1600, 0 },
[9] = { 3200, 0 },
};
#define ADXL313_ACCEL_CHANNEL(index, axis) { \
.type = IIO_ACCEL, \
.address = index, \
.modified = 1, \
.channel2 = IIO_MOD_##axis, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_CALIBBIAS), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_SAMP_FREQ), \
.info_mask_shared_by_type_available = \
BIT(IIO_CHAN_INFO_SAMP_FREQ), \
.scan_type = { \
.realbits = 13, \
}, \
}
static const struct iio_chan_spec adxl313_channels[] = {
ADXL313_ACCEL_CHANNEL(0, X),
ADXL313_ACCEL_CHANNEL(1, Y),
ADXL313_ACCEL_CHANNEL(2, Z),
};
static int adxl313_set_odr(struct adxl313_data *data,
unsigned int freq1, unsigned int freq2)
{
unsigned int i;
for (i = 0; i < ARRAY_SIZE(adxl313_odr_freqs); i++) {
if (adxl313_odr_freqs[i][0] == freq1 &&
adxl313_odr_freqs[i][1] == freq2)
break;
}
if (i == ARRAY_SIZE(adxl313_odr_freqs))
return -EINVAL;
return regmap_update_bits(data->regmap, ADXL313_REG_BW_RATE,
ADXL313_RATE_MSK,
FIELD_PREP(ADXL313_RATE_MSK, ADXL313_RATE_BASE + i));
}
static int adxl313_read_axis(struct adxl313_data *data,
struct iio_chan_spec const *chan)
{
int ret;
mutex_lock(&data->lock);
ret = regmap_bulk_read(data->regmap,
ADXL313_REG_DATA_AXIS(chan->address),
&data->transf_buf, sizeof(data->transf_buf));
if (ret)
goto unlock_ret;
ret = le16_to_cpu(data->transf_buf);
unlock_ret:
mutex_unlock(&data->lock);
return ret;
}
static int adxl313_read_freq_avail(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
const int **vals, int *type, int *length,
long mask)
{
switch (mask) {
case IIO_CHAN_INFO_SAMP_FREQ:
*vals = (const int *)adxl313_odr_freqs;
*length = ARRAY_SIZE(adxl313_odr_freqs) * 2;
*type = IIO_VAL_INT_PLUS_MICRO;
return IIO_AVAIL_LIST;
default:
return -EINVAL;
}
}
static int adxl313_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct adxl313_data *data = iio_priv(indio_dev);
unsigned int regval;
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = adxl313_read_axis(data, chan);
if (ret < 0)
return ret;
*val = sign_extend32(ret, chan->scan_type.realbits - 1);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
/*
* Scale for any g range is given in datasheet as
* 1024 LSB/g = 0.0009765625 * 9.80665 = 0.009576806640625 m/s^2
*/
*val = 0;
*val2 = 9576806;
return IIO_VAL_INT_PLUS_NANO;
case IIO_CHAN_INFO_CALIBBIAS:
ret = regmap_read(data->regmap,
ADXL313_REG_OFS_AXIS(chan->address), ®val);
if (ret)
return ret;
/*
* 8-bit resolution at +/- 0.5g, that is 4x accel data scale
* factor at full resolution
*/
*val = sign_extend32(regval, 7) * 4;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SAMP_FREQ:
ret = regmap_read(data->regmap, ADXL313_REG_BW_RATE, ®val);
if (ret)
return ret;
ret = FIELD_GET(ADXL313_RATE_MSK, regval) - ADXL313_RATE_BASE;
*val = adxl313_odr_freqs[ret][0];
*val2 = adxl313_odr_freqs[ret][1];
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
}
static int adxl313_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct adxl313_data *data = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_CALIBBIAS:
/*
* 8-bit resolution at +/- 0.5g, that is 4x accel data scale
* factor at full resolution
*/
if (clamp_val(val, -128 * 4, 127 * 4) != val)
return -EINVAL;
return regmap_write(data->regmap,
ADXL313_REG_OFS_AXIS(chan->address),
val / 4);
case IIO_CHAN_INFO_SAMP_FREQ:
return adxl313_set_odr(data, val, val2);
default:
return -EINVAL;
}
}
static const struct iio_info adxl313_info = {
.read_raw = adxl313_read_raw,
.write_raw = adxl313_write_raw,
.read_avail = adxl313_read_freq_avail,
};
static int adxl313_setup(struct device *dev, struct adxl313_data *data,
int (*setup)(struct device *, struct regmap *))
{
unsigned int regval;
int ret;
/* Ensures the device is in a consistent state after start up */
ret = regmap_write(data->regmap, ADXL313_REG_SOFT_RESET,
ADXL313_SOFT_RESET);
if (ret)
return ret;
if (setup) {
ret = setup(dev, data->regmap);
if (ret)
return ret;
}
ret = regmap_read(data->regmap, ADXL313_REG_DEVID0, ®val);
if (ret)
return ret;
if (regval != ADXL313_DEVID0) {
dev_err(dev, "Invalid manufacturer ID: 0x%02x\n", regval);
return -ENODEV;
}
ret = regmap_read(data->regmap, ADXL313_REG_DEVID1, ®val);
if (ret)
return ret;
if (regval != ADXL313_DEVID1) {
dev_err(dev, "Invalid mems ID: 0x%02x\n", regval);
return -ENODEV;
}
ret = regmap_read(data->regmap, ADXL313_REG_PARTID, ®val);
if (ret)
return ret;
if (regval != ADXL313_PARTID) {
dev_err(dev, "Invalid device ID: 0x%02x\n", regval);
return -ENODEV;
}
/* Sets the range to +/- 4g */
ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
ADXL313_RANGE_MSK,
FIELD_PREP(ADXL313_RANGE_MSK, ADXL313_RANGE_4G));
if (ret)
return ret;
/* Enables full resolution */
ret = regmap_update_bits(data->regmap, ADXL313_REG_DATA_FORMAT,
ADXL313_FULL_RES, ADXL313_FULL_RES);
if (ret)
return ret;
/* Enables measurement mode */
return regmap_update_bits(data->regmap, ADXL313_REG_POWER_CTL,
ADXL313_POWER_CTL_MSK,
ADXL313_MEASUREMENT_MODE);
}
/**
* adxl313_core_probe() - probe and setup for adxl313 accelerometer
* @dev: Driver model representation of the device
* @regmap: Register map of the device
* @name: Device name buffer reference
* @setup: Setup routine to be executed right before the standard device
* setup, can also be set to NULL if not required
*
* Return: 0 on success, negative errno on error cases
*/
int adxl313_core_probe(struct device *dev,
struct regmap *regmap,
const char *name,
int (*setup)(struct device *, struct regmap *))
{
struct adxl313_data *data;
struct iio_dev *indio_dev;
int ret;
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
data = iio_priv(indio_dev);
data->regmap = regmap;
mutex_init(&data->lock);
indio_dev->name = name;
indio_dev->info = &adxl313_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = adxl313_channels;
indio_dev->num_channels = ARRAY_SIZE(adxl313_channels);
ret = adxl313_setup(dev, data, setup);
if (ret) {
dev_err(dev, "ADXL313 setup failed\n");
return ret;
}
return devm_iio_device_register(dev, indio_dev);
}
EXPORT_SYMBOL_NS_GPL(adxl313_core_probe, IIO_ADXL313);
MODULE_AUTHOR("Lucas Stankus <lucas.p.stankus@gmail.com>");
MODULE_DESCRIPTION("ADXL313 3-Axis Digital Accelerometer core driver");
MODULE_LICENSE("GPL v2");
