iio: accel: Add driver for the BMA400

Add a IIO driver for the Bosch BMA400 3-axes ultra-low power accelerometer.
The driver supports reading from the acceleration and temperature
registers. The driver also supports reading and configuring the output data
rate, oversampling ratio, and scale.

Signed-off-by: Dan Robertson <dan@dlrobertson.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Dan Robertson 2019-12-20 16:00:50 +00:00 committed by Jonathan Cameron
parent 5264c5f4c4
commit 465c811f1f
6 changed files with 1004 additions and 0 deletions

View file

@ -3064,6 +3064,13 @@ S: Supported
F: drivers/net/bonding/
F: include/uapi/linux/if_bonding.h
BOSCH SENSORTEC BMA400 ACCELEROMETER IIO DRIVER
M: Dan Robertson <dan@dlrobertson.com>
L: linux-iio@vger.kernel.org
S: Maintained
F: drivers/iio/accel/bma400*
F: Documentation/devicetree/bindings/iio/accel/bosch,bma400.yaml
BPF (Safe dynamic programs and tools)
M: Alexei Starovoitov <ast@kernel.org>
M: Daniel Borkmann <daniel@iogearbox.net>

View file

@ -112,6 +112,22 @@ config BMA220
To compile this driver as a module, choose M here: the
module will be called bma220_spi.
config BMA400
tristate "Bosch BMA400 3-Axis Accelerometer Driver"
select REGMAP
select BMA400_I2C if I2C
help
Say Y here if you want to build a driver for the Bosch BMA400
triaxial acceleration sensor.
To compile this driver as a module, choose M here: the
module will be called bma400_core and you will also get
bma400_i2c if I2C is enabled.
config BMA400_I2C
tristate
depends on BMA400
config BMC150_ACCEL
tristate "Bosch BMC150 Accelerometer Driver"
select IIO_BUFFER

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@ -14,6 +14,8 @@ obj-$(CONFIG_ADXL372_I2C) += adxl372_i2c.o
obj-$(CONFIG_ADXL372_SPI) += adxl372_spi.o
obj-$(CONFIG_BMA180) += bma180.o
obj-$(CONFIG_BMA220) += bma220_spi.o
obj-$(CONFIG_BMA400) += bma400_core.o
obj-$(CONFIG_BMA400_I2C) += bma400_i2c.o
obj-$(CONFIG_BMC150_ACCEL) += bmc150-accel-core.o
obj-$(CONFIG_BMC150_ACCEL_I2C) += bmc150-accel-i2c.o
obj-$(CONFIG_BMC150_ACCEL_SPI) += bmc150-accel-spi.o

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@ -0,0 +1,95 @@
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Register constants and other forward declarations needed by the bma400
* sources.
*
* Copyright 2019 Dan Robertson <dan@dlrobertson.com>
*/
#ifndef _BMA400_H_
#define _BMA400_H_
#include <linux/bits.h>
#include <linux/regmap.h>
/*
* Read-Only Registers
*/
/* Status and ID registers */
#define BMA400_CHIP_ID_REG 0x00
#define BMA400_ERR_REG 0x02
#define BMA400_STATUS_REG 0x03
/* Acceleration registers */
#define BMA400_X_AXIS_LSB_REG 0x04
#define BMA400_X_AXIS_MSB_REG 0x05
#define BMA400_Y_AXIS_LSB_REG 0x06
#define BMA400_Y_AXIS_MSB_REG 0x07
#define BMA400_Z_AXIS_LSB_REG 0x08
#define BMA400_Z_AXIS_MSB_REG 0x09
/* Sensor time registers */
#define BMA400_SENSOR_TIME0 0x0a
#define BMA400_SENSOR_TIME1 0x0b
#define BMA400_SENSOR_TIME2 0x0c
/* Event and interrupt registers */
#define BMA400_EVENT_REG 0x0d
#define BMA400_INT_STAT0_REG 0x0e
#define BMA400_INT_STAT1_REG 0x0f
#define BMA400_INT_STAT2_REG 0x10
/* Temperature register */
#define BMA400_TEMP_DATA_REG 0x11
/* FIFO length and data registers */
#define BMA400_FIFO_LENGTH0_REG 0x12
#define BMA400_FIFO_LENGTH1_REG 0x13
#define BMA400_FIFO_DATA_REG 0x14
/* Step count registers */
#define BMA400_STEP_CNT0_REG 0x15
#define BMA400_STEP_CNT1_REG 0x16
#define BMA400_STEP_CNT3_REG 0x17
#define BMA400_STEP_STAT_REG 0x18
/*
* Read-write configuration registers
*/
#define BMA400_ACC_CONFIG0_REG 0x19
#define BMA400_ACC_CONFIG1_REG 0x1a
#define BMA400_ACC_CONFIG2_REG 0x1b
#define BMA400_CMD_REG 0x7e
/* Chip ID of BMA 400 devices found in the chip ID register. */
#define BMA400_ID_REG_VAL 0x90
#define BMA400_LP_OSR_SHIFT 5
#define BMA400_NP_OSR_SHIFT 4
#define BMA400_SCALE_SHIFT 6
#define BMA400_TWO_BITS_MASK GENMASK(1, 0)
#define BMA400_LP_OSR_MASK GENMASK(6, 5)
#define BMA400_NP_OSR_MASK GENMASK(5, 4)
#define BMA400_ACC_ODR_MASK GENMASK(3, 0)
#define BMA400_ACC_SCALE_MASK GENMASK(7, 6)
#define BMA400_ACC_ODR_MIN_RAW 0x05
#define BMA400_ACC_ODR_LP_RAW 0x06
#define BMA400_ACC_ODR_MAX_RAW 0x0b
#define BMA400_ACC_ODR_MAX_HZ 800
#define BMA400_ACC_ODR_MIN_WHOLE_HZ 25
#define BMA400_ACC_ODR_MIN_HZ 12
#define BMA400_SCALE_MIN 38357
#define BMA400_SCALE_MAX 306864
extern const struct regmap_config bma400_regmap_config;
int bma400_probe(struct device *dev, struct regmap *regmap, const char *name);
int bma400_remove(struct device *dev);
#endif

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@ -0,0 +1,823 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
* Core IIO driver for Bosch BMA400 triaxial acceleration sensor.
*
* Copyright 2019 Dan Robertson <dan@dlrobertson.com>
*
* TODO:
* - Support for power management
* - Support events and interrupts
* - Create channel for step count
* - Create channel for sensor time
*/
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/regmap.h>
#include "bma400.h"
/*
* The G-range selection may be one of 2g, 4g, 8, or 16g. The scale may
* be selected with the acc_range bits of the ACC_CONFIG1 register.
* NB: This buffer is populated in the device init.
*/
static int bma400_scales[8];
/*
* See the ACC_CONFIG1 section of the datasheet.
* NB: This buffer is populated in the device init.
*/
static int bma400_sample_freqs[14];
static const int bma400_osr_range[] = { 0, 1, 3 };
/* See the ACC_CONFIG0 section of the datasheet */
enum bma400_power_mode {
POWER_MODE_SLEEP = 0x00,
POWER_MODE_LOW = 0x01,
POWER_MODE_NORMAL = 0x02,
POWER_MODE_INVALID = 0x03,
};
struct bma400_sample_freq {
int hz;
int uhz;
};
struct bma400_data {
struct device *dev;
struct regmap *regmap;
struct mutex mutex; /* data register lock */
struct iio_mount_matrix orientation;
enum bma400_power_mode power_mode;
struct bma400_sample_freq sample_freq;
int oversampling_ratio;
int scale;
};
static bool bma400_is_writable_reg(struct device *dev, unsigned int reg)
{
switch (reg) {
case BMA400_CHIP_ID_REG:
case BMA400_ERR_REG:
case BMA400_STATUS_REG:
case BMA400_X_AXIS_LSB_REG:
case BMA400_X_AXIS_MSB_REG:
case BMA400_Y_AXIS_LSB_REG:
case BMA400_Y_AXIS_MSB_REG:
case BMA400_Z_AXIS_LSB_REG:
case BMA400_Z_AXIS_MSB_REG:
case BMA400_SENSOR_TIME0:
case BMA400_SENSOR_TIME1:
case BMA400_SENSOR_TIME2:
case BMA400_EVENT_REG:
case BMA400_INT_STAT0_REG:
case BMA400_INT_STAT1_REG:
case BMA400_INT_STAT2_REG:
case BMA400_TEMP_DATA_REG:
case BMA400_FIFO_LENGTH0_REG:
case BMA400_FIFO_LENGTH1_REG:
case BMA400_FIFO_DATA_REG:
case BMA400_STEP_CNT0_REG:
case BMA400_STEP_CNT1_REG:
case BMA400_STEP_CNT3_REG:
case BMA400_STEP_STAT_REG:
return false;
default:
return true;
}
}
static bool bma400_is_volatile_reg(struct device *dev, unsigned int reg)
{
switch (reg) {
case BMA400_ERR_REG:
case BMA400_STATUS_REG:
case BMA400_X_AXIS_LSB_REG:
case BMA400_X_AXIS_MSB_REG:
case BMA400_Y_AXIS_LSB_REG:
case BMA400_Y_AXIS_MSB_REG:
case BMA400_Z_AXIS_LSB_REG:
case BMA400_Z_AXIS_MSB_REG:
case BMA400_SENSOR_TIME0:
case BMA400_SENSOR_TIME1:
case BMA400_SENSOR_TIME2:
case BMA400_EVENT_REG:
case BMA400_INT_STAT0_REG:
case BMA400_INT_STAT1_REG:
case BMA400_INT_STAT2_REG:
case BMA400_TEMP_DATA_REG:
case BMA400_FIFO_LENGTH0_REG:
case BMA400_FIFO_LENGTH1_REG:
case BMA400_FIFO_DATA_REG:
case BMA400_STEP_CNT0_REG:
case BMA400_STEP_CNT1_REG:
case BMA400_STEP_CNT3_REG:
case BMA400_STEP_STAT_REG:
return true;
default:
return false;
}
}
const struct regmap_config bma400_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = BMA400_CMD_REG,
.cache_type = REGCACHE_RBTREE,
.writeable_reg = bma400_is_writable_reg,
.volatile_reg = bma400_is_volatile_reg,
};
EXPORT_SYMBOL(bma400_regmap_config);
static const struct iio_mount_matrix *
bma400_accel_get_mount_matrix(const struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
struct bma400_data *data = iio_priv(indio_dev);
return &data->orientation;
}
static const struct iio_chan_spec_ext_info bma400_ext_info[] = {
IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, bma400_accel_get_mount_matrix),
{ }
};
#define BMA400_ACC_CHANNEL(_axis) { \
.type = IIO_ACCEL, \
.modified = 1, \
.channel2 = IIO_MOD_##_axis, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
.info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
.ext_info = bma400_ext_info, \
}
static const struct iio_chan_spec bma400_channels[] = {
BMA400_ACC_CHANNEL(X),
BMA400_ACC_CHANNEL(Y),
BMA400_ACC_CHANNEL(Z),
{
.type = IIO_TEMP,
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ),
},
};
static int bma400_get_temp_reg(struct bma400_data *data, int *val, int *val2)
{
unsigned int raw_temp;
int host_temp;
int ret;
if (data->power_mode == POWER_MODE_SLEEP)
return -EBUSY;
ret = regmap_read(data->regmap, BMA400_TEMP_DATA_REG, &raw_temp);
if (ret)
return ret;
host_temp = sign_extend32(raw_temp, 7);
/*
* The formula for the TEMP_DATA register in the datasheet
* is: x * 0.5 + 23
*/
*val = (host_temp >> 1) + 23;
*val2 = (host_temp & 0x1) * 500000;
return IIO_VAL_INT_PLUS_MICRO;
}
static int bma400_get_accel_reg(struct bma400_data *data,
const struct iio_chan_spec *chan,
int *val)
{
__le16 raw_accel;
int lsb_reg;
int ret;
if (data->power_mode == POWER_MODE_SLEEP)
return -EBUSY;
switch (chan->channel2) {
case IIO_MOD_X:
lsb_reg = BMA400_X_AXIS_LSB_REG;
break;
case IIO_MOD_Y:
lsb_reg = BMA400_Y_AXIS_LSB_REG;
break;
case IIO_MOD_Z:
lsb_reg = BMA400_Z_AXIS_LSB_REG;
break;
default:
dev_err(data->dev, "invalid axis channel modifier\n");
return -EINVAL;
}
/* bulk read two registers, with the base being the LSB register */
ret = regmap_bulk_read(data->regmap, lsb_reg, &raw_accel,
sizeof(raw_accel));
if (ret)
return ret;
*val = sign_extend32(le16_to_cpu(raw_accel), 11);
return IIO_VAL_INT;
}
static void bma400_output_data_rate_from_raw(int raw, unsigned int *val,
unsigned int *val2)
{
*val = BMA400_ACC_ODR_MAX_HZ >> (BMA400_ACC_ODR_MAX_RAW - raw);
if (raw > BMA400_ACC_ODR_MIN_RAW)
*val2 = 0;
else
*val2 = 500000;
}
static int bma400_get_accel_output_data_rate(struct bma400_data *data)
{
unsigned int val;
unsigned int odr;
int ret;
switch (data->power_mode) {
case POWER_MODE_LOW:
/*
* Runs at a fixed rate in low-power mode. See section 4.3
* in the datasheet.
*/
bma400_output_data_rate_from_raw(BMA400_ACC_ODR_LP_RAW,
&data->sample_freq.hz,
&data->sample_freq.uhz);
return 0;
case POWER_MODE_NORMAL:
/*
* In normal mode the ODR can be found in the ACC_CONFIG1
* register.
*/
ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &val);
if (ret)
goto error;
odr = val & BMA400_ACC_ODR_MASK;
if (odr < BMA400_ACC_ODR_MIN_RAW ||
odr > BMA400_ACC_ODR_MAX_RAW) {
ret = -EINVAL;
goto error;
}
bma400_output_data_rate_from_raw(odr, &data->sample_freq.hz,
&data->sample_freq.uhz);
return 0;
case POWER_MODE_SLEEP:
data->sample_freq.hz = 0;
data->sample_freq.uhz = 0;
return 0;
default:
ret = 0;
goto error;
}
error:
data->sample_freq.hz = -1;
data->sample_freq.uhz = -1;
return ret;
}
static int bma400_set_accel_output_data_rate(struct bma400_data *data,
int hz, int uhz)
{
unsigned int idx;
unsigned int odr;
unsigned int val;
int ret;
if (hz >= BMA400_ACC_ODR_MIN_WHOLE_HZ) {
if (uhz || hz > BMA400_ACC_ODR_MAX_HZ)
return -EINVAL;
/* Note this works because MIN_WHOLE_HZ is odd */
idx = __ffs(hz);
if (hz >> idx != BMA400_ACC_ODR_MIN_WHOLE_HZ)
return -EINVAL;
idx += BMA400_ACC_ODR_MIN_RAW + 1;
} else if (hz == BMA400_ACC_ODR_MIN_HZ && uhz == 500000) {
idx = BMA400_ACC_ODR_MIN_RAW;
} else {
return -EINVAL;
}
ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &val);
if (ret)
return ret;
/* preserve the range and normal mode osr */
odr = (~BMA400_ACC_ODR_MASK & val) | idx;
ret = regmap_write(data->regmap, BMA400_ACC_CONFIG1_REG, odr);
if (ret)
return ret;
bma400_output_data_rate_from_raw(idx, &data->sample_freq.hz,
&data->sample_freq.uhz);
return 0;
}
static int bma400_get_accel_oversampling_ratio(struct bma400_data *data)
{
unsigned int val;
unsigned int osr;
int ret;
/*
* The oversampling ratio is stored in a different register
* based on the power-mode. In normal mode the OSR is stored
* in ACC_CONFIG1. In low-power mode it is stored in
* ACC_CONFIG0.
*/
switch (data->power_mode) {
case POWER_MODE_LOW:
ret = regmap_read(data->regmap, BMA400_ACC_CONFIG0_REG, &val);
if (ret) {
data->oversampling_ratio = -1;
return ret;
}
osr = (val & BMA400_LP_OSR_MASK) >> BMA400_LP_OSR_SHIFT;
data->oversampling_ratio = osr;
return 0;
case POWER_MODE_NORMAL:
ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &val);
if (ret) {
data->oversampling_ratio = -1;
return ret;
}
osr = (val & BMA400_NP_OSR_MASK) >> BMA400_NP_OSR_SHIFT;
data->oversampling_ratio = osr;
return 0;
case POWER_MODE_SLEEP:
data->oversampling_ratio = 0;
return 0;
default:
data->oversampling_ratio = -1;
return -EINVAL;
}
}
static int bma400_set_accel_oversampling_ratio(struct bma400_data *data,
int val)
{
unsigned int acc_config;
int ret;
if (val & ~BMA400_TWO_BITS_MASK)
return -EINVAL;
/*
* The oversampling ratio is stored in a different register
* based on the power-mode.
*/
switch (data->power_mode) {
case POWER_MODE_LOW:
ret = regmap_read(data->regmap, BMA400_ACC_CONFIG0_REG,
&acc_config);
if (ret)
return ret;
ret = regmap_write(data->regmap, BMA400_ACC_CONFIG0_REG,
(acc_config & ~BMA400_LP_OSR_MASK) |
(val << BMA400_LP_OSR_SHIFT));
if (ret) {
dev_err(data->dev, "Failed to write out OSR\n");
return ret;
}
data->oversampling_ratio = val;
return 0;
case POWER_MODE_NORMAL:
ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG,
&acc_config);
if (ret)
return ret;
ret = regmap_write(data->regmap, BMA400_ACC_CONFIG1_REG,
(acc_config & ~BMA400_NP_OSR_MASK) |
(val << BMA400_NP_OSR_SHIFT));
if (ret) {
dev_err(data->dev, "Failed to write out OSR\n");
return ret;
}
data->oversampling_ratio = val;
return 0;
default:
return -EINVAL;
}
return ret;
}
static int bma400_accel_scale_to_raw(struct bma400_data *data,
unsigned int val)
{
int raw;
if (val == 0)
return -EINVAL;
/* Note this works because BMA400_SCALE_MIN is odd */
raw = __ffs(val);
if (val >> raw != BMA400_SCALE_MIN)
return -EINVAL;
return raw;
}
static int bma400_get_accel_scale(struct bma400_data *data)
{
unsigned int raw_scale;
unsigned int val;
int ret;
ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &val);
if (ret)
return ret;
raw_scale = (val & BMA400_ACC_SCALE_MASK) >> BMA400_SCALE_SHIFT;
if (raw_scale > BMA400_TWO_BITS_MASK)
return -EINVAL;
data->scale = BMA400_SCALE_MIN << raw_scale;
return 0;
}
static int bma400_set_accel_scale(struct bma400_data *data, unsigned int val)
{
unsigned int acc_config;
int raw;
int ret;
ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &acc_config);
if (ret)
return ret;
raw = bma400_accel_scale_to_raw(data, val);
if (raw < 0)
return raw;
ret = regmap_write(data->regmap, BMA400_ACC_CONFIG1_REG,
(acc_config & ~BMA400_ACC_SCALE_MASK) |
(raw << BMA400_SCALE_SHIFT));
if (ret)
return ret;
data->scale = val;
return 0;
}
static int bma400_get_power_mode(struct bma400_data *data)
{
unsigned int val;
int ret;
ret = regmap_read(data->regmap, BMA400_STATUS_REG, &val);
if (ret) {
dev_err(data->dev, "Failed to read status register\n");
return ret;
}
data->power_mode = (val >> 1) & BMA400_TWO_BITS_MASK;
return 0;
}
static int bma400_set_power_mode(struct bma400_data *data,
enum bma400_power_mode mode)
{
unsigned int val;
int ret;
ret = regmap_read(data->regmap, BMA400_ACC_CONFIG0_REG, &val);
if (ret)
return ret;
if (data->power_mode == mode)
return 0;
if (mode == POWER_MODE_INVALID)
return -EINVAL;
/* Preserve the low-power oversample ratio etc */
ret = regmap_write(data->regmap, BMA400_ACC_CONFIG0_REG,
mode | (val & ~BMA400_TWO_BITS_MASK));
if (ret) {
dev_err(data->dev, "Failed to write to power-mode\n");
return ret;
}
data->power_mode = mode;
/*
* Update our cached osr and odr based on the new
* power-mode.
*/
bma400_get_accel_output_data_rate(data);
bma400_get_accel_oversampling_ratio(data);
return 0;
}
static void bma400_init_tables(void)
{
int raw;
int i;
for (i = 0; i + 1 < ARRAY_SIZE(bma400_sample_freqs); i += 2) {
raw = (i / 2) + 5;
bma400_output_data_rate_from_raw(raw, &bma400_sample_freqs[i],
&bma400_sample_freqs[i + 1]);
}
for (i = 0; i + 1 < ARRAY_SIZE(bma400_scales); i += 2) {
raw = i / 2;
bma400_scales[i] = 0;
bma400_scales[i + 1] = BMA400_SCALE_MIN << raw;
}
}
static int bma400_init(struct bma400_data *data)
{
unsigned int val;
int ret;
/* Try to read chip_id register. It must return 0x90. */
ret = regmap_read(data->regmap, BMA400_CHIP_ID_REG, &val);
if (ret) {
dev_err(data->dev, "Failed to read chip id register\n");
goto out;
}
if (val != BMA400_ID_REG_VAL) {
dev_err(data->dev, "Chip ID mismatch\n");
ret = -ENODEV;
goto out;
}
ret = bma400_get_power_mode(data);
if (ret) {
dev_err(data->dev, "Failed to get the initial power-mode\n");
goto out;
}
if (data->power_mode != POWER_MODE_NORMAL) {
ret = bma400_set_power_mode(data, POWER_MODE_NORMAL);
if (ret) {
dev_err(data->dev, "Failed to wake up the device\n");
goto out;
}
/*
* TODO: The datasheet waits 1500us here in the example, but
* lists 2/ODR as the wakeup time.
*/
usleep_range(1500, 2000);
}
bma400_init_tables();
ret = bma400_get_accel_output_data_rate(data);
if (ret)
goto out;
ret = bma400_get_accel_oversampling_ratio(data);
if (ret)
goto out;
ret = bma400_get_accel_scale(data);
if (ret)
goto out;
/*
* Once the interrupt engine is supported we might use the
* data_src_reg, but for now ensure this is set to the
* variable ODR filter selectable by the sample frequency
* channel.
*/
return regmap_write(data->regmap, BMA400_ACC_CONFIG2_REG, 0x00);
out:
return ret;
}
static int bma400_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int *val,
int *val2, long mask)
{
struct bma400_data *data = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_PROCESSED:
mutex_lock(&data->mutex);
ret = bma400_get_temp_reg(data, val, val2);
mutex_unlock(&data->mutex);
return ret;
case IIO_CHAN_INFO_RAW:
mutex_lock(&data->mutex);
ret = bma400_get_accel_reg(data, chan, val);
mutex_unlock(&data->mutex);
return ret;
case IIO_CHAN_INFO_SAMP_FREQ:
switch (chan->type) {
case IIO_ACCEL:
if (data->sample_freq.hz < 0)
return -EINVAL;
*val = data->sample_freq.hz;
*val2 = data->sample_freq.uhz;
return IIO_VAL_INT_PLUS_MICRO;
case IIO_TEMP:
/*
* Runs at a fixed sampling frequency. See Section 4.4
* of the datasheet.
*/
*val = 6;
*val2 = 250000;
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
case IIO_CHAN_INFO_SCALE:
*val = 0;
*val2 = data->scale;
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
/*
* TODO: We could avoid this logic and returning -EINVAL here if
* we set both the low-power and normal mode OSR registers when
* we configure the device.
*/
if (data->oversampling_ratio < 0)
return -EINVAL;
*val = data->oversampling_ratio;
return IIO_VAL_INT;
default:
return -EINVAL;
}
}
static int bma400_read_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_SCALE:
*type = IIO_VAL_INT_PLUS_MICRO;
*vals = bma400_scales;
*length = ARRAY_SIZE(bma400_scales);
return IIO_AVAIL_LIST;
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
*type = IIO_VAL_INT;
*vals = bma400_osr_range;
*length = ARRAY_SIZE(bma400_osr_range);
return IIO_AVAIL_RANGE;
case IIO_CHAN_INFO_SAMP_FREQ:
*type = IIO_VAL_INT_PLUS_MICRO;
*vals = bma400_sample_freqs;
*length = ARRAY_SIZE(bma400_sample_freqs);
return IIO_AVAIL_LIST;
default:
return -EINVAL;
}
}
static int bma400_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int val, int val2,
long mask)
{
struct bma400_data *data = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_SAMP_FREQ:
/*
* The sample frequency is readonly for the temperature
* register and a fixed value in low-power mode.
*/
if (chan->type != IIO_ACCEL)
return -EINVAL;
mutex_lock(&data->mutex);
ret = bma400_set_accel_output_data_rate(data, val, val2);
mutex_unlock(&data->mutex);
return ret;
case IIO_CHAN_INFO_SCALE:
if (val != 0 || val2 > BMA400_SCALE_MAX)
return -EINVAL;
mutex_lock(&data->mutex);
ret = bma400_set_accel_scale(data, val2);
mutex_unlock(&data->mutex);
return ret;
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
mutex_lock(&data->mutex);
ret = bma400_set_accel_oversampling_ratio(data, val);
mutex_unlock(&data->mutex);
return ret;
default:
return -EINVAL;
}
}
static int bma400_write_raw_get_fmt(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
long mask)
{
switch (mask) {
case IIO_CHAN_INFO_SAMP_FREQ:
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_SCALE:
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
return IIO_VAL_INT;
default:
return -EINVAL;
}
}
static const struct iio_info bma400_info = {
.read_raw = bma400_read_raw,
.read_avail = bma400_read_avail,
.write_raw = bma400_write_raw,
.write_raw_get_fmt = bma400_write_raw_get_fmt,
};
int bma400_probe(struct device *dev, struct regmap *regmap, const char *name)
{
struct iio_dev *indio_dev;
struct bma400_data *data;
int ret;
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
data = iio_priv(indio_dev);
data->regmap = regmap;
data->dev = dev;
ret = bma400_init(data);
if (ret)
return ret;
ret = iio_read_mount_matrix(dev, "mount-matrix", &data->orientation);
if (ret)
return ret;
mutex_init(&data->mutex);
indio_dev->dev.parent = dev;
indio_dev->name = name;
indio_dev->info = &bma400_info;
indio_dev->channels = bma400_channels;
indio_dev->num_channels = ARRAY_SIZE(bma400_channels);
indio_dev->modes = INDIO_DIRECT_MODE;
dev_set_drvdata(dev, indio_dev);
return iio_device_register(indio_dev);
}
EXPORT_SYMBOL(bma400_probe);
int bma400_remove(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct bma400_data *data = iio_priv(indio_dev);
int ret;
mutex_lock(&data->mutex);
ret = bma400_set_power_mode(data, POWER_MODE_SLEEP);
mutex_unlock(&data->mutex);
iio_device_unregister(indio_dev);
return ret;
}
EXPORT_SYMBOL(bma400_remove);
MODULE_AUTHOR("Dan Robertson <dan@dlrobertson.com>");
MODULE_DESCRIPTION("Bosch BMA400 triaxial acceleration sensor core");
MODULE_LICENSE("GPL");

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@ -0,0 +1,61 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
* I2C IIO driver for Bosch BMA400 triaxial acceleration sensor.
*
* Copyright 2019 Dan Robertson <dan@dlrobertson.com>
*
* I2C address is either 0x14 or 0x15 depending on SDO
*/
#include <linux/i2c.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include "bma400.h"
static int bma400_i2c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct regmap *regmap;
regmap = devm_regmap_init_i2c(client, &bma400_regmap_config);
if (IS_ERR(regmap)) {
dev_err(&client->dev, "failed to create regmap\n");
return PTR_ERR(regmap);
}
return bma400_probe(&client->dev, regmap, id->name);
}
static int bma400_i2c_remove(struct i2c_client *client)
{
return bma400_remove(&client->dev);
}
static const struct i2c_device_id bma400_i2c_ids[] = {
{ "bma400", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, bma400_i2c_ids);
static const struct of_device_id bma400_of_i2c_match[] = {
{ .compatible = "bosch,bma400" },
{ }
};
MODULE_DEVICE_TABLE(of, bma400_of_i2c_match);
static struct i2c_driver bma400_i2c_driver = {
.driver = {
.name = "bma400",
.of_match_table = bma400_of_i2c_match,
},
.probe = bma400_i2c_probe,
.remove = bma400_i2c_remove,
.id_table = bma400_i2c_ids,
};
module_i2c_driver(bma400_i2c_driver);
MODULE_AUTHOR("Dan Robertson <dan@dlrobertson.com>");
MODULE_DESCRIPTION("Bosch BMA400 triaxial acceleration sensor (I2C)");
MODULE_LICENSE("GPL");