iio: imu: inv_mpu6050: add MPU925x magnetometer support

Add support of driving MPU9250 magnetometer connected on i2c
auxiliary bus using the MPU i2c master.

Signed-off-by: Jean-Baptiste Maneyrol <jmaneyrol@invensense.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Jean-Baptiste Maneyrol 2019-09-16 09:42:07 +00:00 committed by Jonathan Cameron
parent 16ef433769
commit b1392de061
5 changed files with 538 additions and 4 deletions

View File

@ -5,7 +5,7 @@
obj-$(CONFIG_INV_MPU6050_IIO) += inv-mpu6050.o
inv-mpu6050-y := inv_mpu_core.o inv_mpu_ring.o inv_mpu_trigger.o \
inv_mpu_aux.o
inv_mpu_aux.o inv_mpu_magn.o
obj-$(CONFIG_INV_MPU6050_I2C) += inv-mpu6050-i2c.o
inv-mpu6050-i2c-y := inv_mpu_i2c.o inv_mpu_acpi.o

View File

@ -17,6 +17,7 @@
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include "inv_mpu_iio.h"
#include "inv_mpu_magn.h"
/*
* this is the gyro scale translated from dynamic range plus/minus
@ -332,6 +333,11 @@ static int inv_mpu6050_init_config(struct iio_dev *indio_dev)
*/
st->chip_period = NSEC_PER_MSEC;
/* magn chip init, noop if not present in the chip */
result = inv_mpu_magn_probe(st);
if (result)
goto error_power_off;
return inv_mpu6050_set_power_itg(st, false);
error_power_off:
@ -411,6 +417,9 @@ static int inv_mpu6050_read_channel_data(struct iio_dev *indio_dev,
ret = inv_mpu6050_sensor_show(st, st->reg->temperature,
IIO_MOD_X, val);
break;
case IIO_MAGN:
ret = inv_mpu_magn_read(st, chan->channel2, val);
break;
default:
ret = -EINVAL;
break;
@ -469,6 +478,8 @@ inv_mpu6050_read_raw(struct iio_dev *indio_dev,
*val2 = INV_MPU6050_TEMP_SCALE;
return IIO_VAL_INT_PLUS_MICRO;
case IIO_MAGN:
return inv_mpu_magn_get_scale(st, chan, val, val2);
default:
return -EINVAL;
}
@ -710,6 +721,11 @@ inv_mpu6050_fifo_rate_store(struct device *dev, struct device_attribute *attr,
if (result)
goto fifo_rate_fail_power_off;
/* update rate for magn, noop if not present in chip */
result = inv_mpu_magn_set_rate(st, fifo_rate);
if (result)
goto fifo_rate_fail_power_off;
fifo_rate_fail_power_off:
result |= inv_mpu6050_set_power_itg(st, false);
fifo_rate_fail_unlock:
@ -795,8 +811,14 @@ inv_get_mount_matrix(const struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
struct inv_mpu6050_state *data = iio_priv(indio_dev);
const struct iio_mount_matrix *matrix;
return &data->orientation;
if (chan->type == IIO_MAGN)
matrix = &data->magn_orient;
else
matrix = &data->orientation;
return matrix;
}
static const struct iio_chan_spec_ext_info inv_ext_info[] = {
@ -864,6 +886,98 @@ static const unsigned long inv_mpu_scan_masks[] = {
0,
};
#define INV_MPU9X50_MAGN_CHAN(_chan2, _bits, _index) \
{ \
.type = IIO_MAGN, \
.modified = 1, \
.channel2 = _chan2, \
.info_mask_separate = BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_RAW), \
.scan_index = _index, \
.scan_type = { \
.sign = 's', \
.realbits = _bits, \
.storagebits = 16, \
.shift = 0, \
.endianness = IIO_BE, \
}, \
.ext_info = inv_ext_info, \
}
static const struct iio_chan_spec inv_mpu9250_channels[] = {
IIO_CHAN_SOFT_TIMESTAMP(INV_MPU9X50_SCAN_TIMESTAMP),
/*
* Note that temperature should only be via polled reading only,
* not the final scan elements output.
*/
{
.type = IIO_TEMP,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW)
| BIT(IIO_CHAN_INFO_OFFSET)
| BIT(IIO_CHAN_INFO_SCALE),
.scan_index = -1,
},
INV_MPU6050_CHAN(IIO_ANGL_VEL, IIO_MOD_X, INV_MPU6050_SCAN_GYRO_X),
INV_MPU6050_CHAN(IIO_ANGL_VEL, IIO_MOD_Y, INV_MPU6050_SCAN_GYRO_Y),
INV_MPU6050_CHAN(IIO_ANGL_VEL, IIO_MOD_Z, INV_MPU6050_SCAN_GYRO_Z),
INV_MPU6050_CHAN(IIO_ACCEL, IIO_MOD_X, INV_MPU6050_SCAN_ACCL_X),
INV_MPU6050_CHAN(IIO_ACCEL, IIO_MOD_Y, INV_MPU6050_SCAN_ACCL_Y),
INV_MPU6050_CHAN(IIO_ACCEL, IIO_MOD_Z, INV_MPU6050_SCAN_ACCL_Z),
/* Magnetometer resolution is 16 bits */
INV_MPU9X50_MAGN_CHAN(IIO_MOD_X, 16, INV_MPU9X50_SCAN_MAGN_X),
INV_MPU9X50_MAGN_CHAN(IIO_MOD_Y, 16, INV_MPU9X50_SCAN_MAGN_Y),
INV_MPU9X50_MAGN_CHAN(IIO_MOD_Z, 16, INV_MPU9X50_SCAN_MAGN_Z),
};
static const unsigned long inv_mpu9x50_scan_masks[] = {
/* 3-axis accel */
BIT(INV_MPU6050_SCAN_ACCL_X)
| BIT(INV_MPU6050_SCAN_ACCL_Y)
| BIT(INV_MPU6050_SCAN_ACCL_Z),
/* 3-axis gyro */
BIT(INV_MPU6050_SCAN_GYRO_X)
| BIT(INV_MPU6050_SCAN_GYRO_Y)
| BIT(INV_MPU6050_SCAN_GYRO_Z),
/* 3-axis magn */
BIT(INV_MPU9X50_SCAN_MAGN_X)
| BIT(INV_MPU9X50_SCAN_MAGN_Y)
| BIT(INV_MPU9X50_SCAN_MAGN_Z),
/* 6-axis accel + gyro */
BIT(INV_MPU6050_SCAN_ACCL_X)
| BIT(INV_MPU6050_SCAN_ACCL_Y)
| BIT(INV_MPU6050_SCAN_ACCL_Z)
| BIT(INV_MPU6050_SCAN_GYRO_X)
| BIT(INV_MPU6050_SCAN_GYRO_Y)
| BIT(INV_MPU6050_SCAN_GYRO_Z),
/* 6-axis accel + magn */
BIT(INV_MPU6050_SCAN_ACCL_X)
| BIT(INV_MPU6050_SCAN_ACCL_Y)
| BIT(INV_MPU6050_SCAN_ACCL_Z)
| BIT(INV_MPU9X50_SCAN_MAGN_X)
| BIT(INV_MPU9X50_SCAN_MAGN_Y)
| BIT(INV_MPU9X50_SCAN_MAGN_Z),
/* 6-axis gyro + magn */
BIT(INV_MPU6050_SCAN_GYRO_X)
| BIT(INV_MPU6050_SCAN_GYRO_Y)
| BIT(INV_MPU6050_SCAN_GYRO_Z)
| BIT(INV_MPU9X50_SCAN_MAGN_X)
| BIT(INV_MPU9X50_SCAN_MAGN_Y)
| BIT(INV_MPU9X50_SCAN_MAGN_Z),
/* 9-axis accel + gyro + magn */
BIT(INV_MPU6050_SCAN_ACCL_X)
| BIT(INV_MPU6050_SCAN_ACCL_Y)
| BIT(INV_MPU6050_SCAN_ACCL_Z)
| BIT(INV_MPU6050_SCAN_GYRO_X)
| BIT(INV_MPU6050_SCAN_GYRO_Y)
| BIT(INV_MPU6050_SCAN_GYRO_Z)
| BIT(INV_MPU9X50_SCAN_MAGN_X)
| BIT(INV_MPU9X50_SCAN_MAGN_Y)
| BIT(INV_MPU9X50_SCAN_MAGN_Z),
0,
};
static const struct iio_chan_spec inv_icm20602_channels[] = {
IIO_CHAN_SOFT_TIMESTAMP(INV_ICM20602_SCAN_TIMESTAMP),
{
@ -1145,6 +1259,11 @@ int inv_mpu_core_probe(struct regmap *regmap, int irq, const char *name,
return result;
}
/* fill magnetometer orientation */
result = inv_mpu_magn_set_orient(st);
if (result)
return result;
/* power is turned on inside check chip type*/
result = inv_check_and_setup_chip(st);
if (result)
@ -1168,14 +1287,33 @@ int inv_mpu_core_probe(struct regmap *regmap, int irq, const char *name,
if (inv_mpu_bus_setup)
inv_mpu_bus_setup(indio_dev);
if (chip_type == INV_ICM20602) {
switch (chip_type) {
case INV_MPU9250:
case INV_MPU9255:
/*
* Use magnetometer inside the chip only if there is no i2c
* auxiliary device in use.
*/
if (!st->magn_disabled) {
indio_dev->channels = inv_mpu9250_channels;
indio_dev->num_channels = ARRAY_SIZE(inv_mpu9250_channels);
indio_dev->available_scan_masks = inv_mpu9x50_scan_masks;
} else {
indio_dev->channels = inv_mpu_channels;
indio_dev->num_channels = ARRAY_SIZE(inv_mpu_channels);
indio_dev->available_scan_masks = inv_mpu_scan_masks;
}
break;
case INV_ICM20602:
indio_dev->channels = inv_icm20602_channels;
indio_dev->num_channels = ARRAY_SIZE(inv_icm20602_channels);
indio_dev->available_scan_masks = inv_icm20602_scan_masks;
} else {
break;
default:
indio_dev->channels = inv_mpu_channels;
indio_dev->num_channels = ARRAY_SIZE(inv_mpu_channels);
indio_dev->available_scan_masks = inv_mpu_scan_masks;
break;
}
indio_dev->info = &mpu_info;

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@ -130,6 +130,8 @@ struct inv_mpu6050_hw {
* @data_timestamp: timestamp for next data sample.
* @vddio_supply voltage regulator for the chip.
* @magn_disabled: magnetometer disabled for backward compatibility reason.
* @magn_raw_to_gauss: coefficient to convert mag raw value to Gauss.
* @magn_orient: magnetometer sensor chip orientation if available.
*/
struct inv_mpu6050_state {
struct mutex lock;
@ -152,6 +154,8 @@ struct inv_mpu6050_state {
s64 data_timestamp;
struct regulator *vddio_supply;
bool magn_disabled;
s32 magn_raw_to_gauss[3];
struct iio_mount_matrix magn_orient;
};
/*register and associated bit definition*/

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@ -0,0 +1,356 @@
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2019 TDK-InvenSense, Inc.
*/
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/string.h>
#include "inv_mpu_aux.h"
#include "inv_mpu_iio.h"
#include "inv_mpu_magn.h"
/*
* MPU9250 magnetometer is an AKM AK8963 chip on I2C aux bus
*/
#define INV_MPU_MAGN_I2C_ADDR 0x0C
#define INV_MPU_MAGN_REG_WIA 0x00
#define INV_MPU_MAGN_BITS_WIA 0x48
#define INV_MPU_MAGN_REG_ST1 0x02
#define INV_MPU_MAGN_BIT_DRDY 0x01
#define INV_MPU_MAGN_BIT_DOR 0x02
#define INV_MPU_MAGN_REG_DATA 0x03
#define INV_MPU_MAGN_REG_ST2 0x09
#define INV_MPU_MAGN_BIT_HOFL 0x08
#define INV_MPU_MAGN_BIT_BITM 0x10
#define INV_MPU_MAGN_REG_CNTL1 0x0A
#define INV_MPU_MAGN_BITS_MODE_PWDN 0x00
#define INV_MPU_MAGN_BITS_MODE_SINGLE 0x01
#define INV_MPU_MAGN_BITS_MODE_FUSE 0x0F
#define INV_MPU_MAGN_BIT_OUTPUT_BIT 0x10
#define INV_MPU_MAGN_REG_CNTL2 0x0B
#define INV_MPU_MAGN_BIT_SRST 0x01
#define INV_MPU_MAGN_REG_ASAX 0x10
#define INV_MPU_MAGN_REG_ASAY 0x11
#define INV_MPU_MAGN_REG_ASAZ 0x12
/* Magnetometer maximum frequency */
#define INV_MPU_MAGN_FREQ_HZ_MAX 50
static bool inv_magn_supported(const struct inv_mpu6050_state *st)
{
switch (st->chip_type) {
case INV_MPU9250:
case INV_MPU9255:
return true;
default:
return false;
}
}
/* init magnetometer chip */
static int inv_magn_init(struct inv_mpu6050_state *st)
{
uint8_t val;
uint8_t asa[3];
int ret;
/* check whoami */
ret = inv_mpu_aux_read(st, INV_MPU_MAGN_I2C_ADDR, INV_MPU_MAGN_REG_WIA,
&val, sizeof(val));
if (ret)
return ret;
if (val != INV_MPU_MAGN_BITS_WIA)
return -ENODEV;
/* reset chip */
ret = inv_mpu_aux_write(st, INV_MPU_MAGN_I2C_ADDR,
INV_MPU_MAGN_REG_CNTL2,
INV_MPU_MAGN_BIT_SRST);
if (ret)
return ret;
/* read fuse ROM data */
ret = inv_mpu_aux_write(st, INV_MPU_MAGN_I2C_ADDR,
INV_MPU_MAGN_REG_CNTL1,
INV_MPU_MAGN_BITS_MODE_FUSE);
if (ret)
return ret;
ret = inv_mpu_aux_read(st, INV_MPU_MAGN_I2C_ADDR, INV_MPU_MAGN_REG_ASAX,
asa, sizeof(asa));
if (ret)
return ret;
/* switch back to power-down */
ret = inv_mpu_aux_write(st, INV_MPU_MAGN_I2C_ADDR,
INV_MPU_MAGN_REG_CNTL1,
INV_MPU_MAGN_BITS_MODE_PWDN);
if (ret)
return ret;
/*
* Sensitivity adjustement and scale to Gauss
*
* Hadj = H * (((ASA - 128) * 0.5 / 128) + 1)
* Factor simplification:
* Hadj = H * ((ASA + 128) / 256)
*
* Sensor sentivity
* 0.15 uT in 16 bits mode
* 1 uT = 0.01 G and value is in micron (1e6)
* sensitvity = 0.15 uT * 0.01 * 1e6
*
* raw_to_gauss = Hadj * 1500
*/
st->magn_raw_to_gauss[0] = (((int32_t)asa[0] + 128) * 1500) / 256;
st->magn_raw_to_gauss[1] = (((int32_t)asa[1] + 128) * 1500) / 256;
st->magn_raw_to_gauss[2] = (((int32_t)asa[2] + 128) * 1500) / 256;
return 0;
}
/**
* inv_mpu_magn_probe() - probe and setup magnetometer chip
* @st: driver internal state
*
* Returns 0 on success, a negative error code otherwise
*
* It is probing the chip and setting up all needed i2c transfers.
* Noop if there is no magnetometer in the chip.
*/
int inv_mpu_magn_probe(struct inv_mpu6050_state *st)
{
int ret;
/* quit if chip is not supported */
if (!inv_magn_supported(st))
return 0;
/* configure i2c master aux port */
ret = inv_mpu_aux_init(st);
if (ret)
return ret;
/* check and init mag chip */
ret = inv_magn_init(st);
if (ret)
return ret;
/*
* configure mpu i2c master accesses
* i2c SLV0: read sensor data, 7 bytes data(6)-ST2
* Byte swap data to store them in big-endian in impair address groups
*/
ret = regmap_write(st->map, INV_MPU6050_REG_I2C_SLV_ADDR(0),
INV_MPU6050_BIT_I2C_SLV_RNW | INV_MPU_MAGN_I2C_ADDR);
if (ret)
return ret;
ret = regmap_write(st->map, INV_MPU6050_REG_I2C_SLV_REG(0),
INV_MPU_MAGN_REG_DATA);
if (ret)
return ret;
ret = regmap_write(st->map, INV_MPU6050_REG_I2C_SLV_CTRL(0),
INV_MPU6050_BIT_SLV_EN |
INV_MPU6050_BIT_SLV_BYTE_SW |
INV_MPU6050_BIT_SLV_GRP |
INV_MPU9X50_BYTES_MAGN);
if (ret)
return ret;
/* i2c SLV1: launch single measurement */
ret = regmap_write(st->map, INV_MPU6050_REG_I2C_SLV_ADDR(1),
INV_MPU_MAGN_I2C_ADDR);
if (ret)
return ret;
ret = regmap_write(st->map, INV_MPU6050_REG_I2C_SLV_REG(1),
INV_MPU_MAGN_REG_CNTL1);
if (ret)
return ret;
/* add 16 bits mode */
ret = regmap_write(st->map, INV_MPU6050_REG_I2C_SLV_DO(1),
INV_MPU_MAGN_BITS_MODE_SINGLE |
INV_MPU_MAGN_BIT_OUTPUT_BIT);
if (ret)
return ret;
return regmap_write(st->map, INV_MPU6050_REG_I2C_SLV_CTRL(1),
INV_MPU6050_BIT_SLV_EN | 1);
}
/**
* inv_mpu_magn_set_rate() - set magnetometer sampling rate
* @st: driver internal state
* @fifo_rate: mpu set fifo rate
*
* Returns 0 on success, a negative error code otherwise
*
* Limit sampling frequency to the maximum value supported by the
* magnetometer chip. Resulting in duplicated data for higher frequencies.
* Noop if there is no magnetometer in the chip.
*/
int inv_mpu_magn_set_rate(const struct inv_mpu6050_state *st, int fifo_rate)
{
uint8_t d;
/* quit if chip is not supported */
if (!inv_magn_supported(st))
return 0;
/*
* update i2c master delay to limit mag sampling to max frequency
* compute fifo_rate divider d: rate = fifo_rate / (d + 1)
*/
if (fifo_rate > INV_MPU_MAGN_FREQ_HZ_MAX)
d = fifo_rate / INV_MPU_MAGN_FREQ_HZ_MAX - 1;
else
d = 0;
return regmap_write(st->map, INV_MPU6050_REG_I2C_SLV4_CTRL, d);
}
/**
* inv_mpu_magn_set_orient() - fill magnetometer mounting matrix
* @st: driver internal state
*
* Returns 0 on success, a negative error code otherwise
*
* Fill magnetometer mounting matrix using the provided chip matrix.
*/
int inv_mpu_magn_set_orient(struct inv_mpu6050_state *st)
{
const char *orient;
char *str;
int i;
/* fill magnetometer orientation */
switch (st->chip_type) {
case INV_MPU9250:
case INV_MPU9255:
/* x <- y */
st->magn_orient.rotation[0] = st->orientation.rotation[3];
st->magn_orient.rotation[1] = st->orientation.rotation[4];
st->magn_orient.rotation[2] = st->orientation.rotation[5];
/* y <- x */
st->magn_orient.rotation[3] = st->orientation.rotation[0];
st->magn_orient.rotation[4] = st->orientation.rotation[1];
st->magn_orient.rotation[5] = st->orientation.rotation[2];
/* z <- -z */
for (i = 0; i < 3; ++i) {
orient = st->orientation.rotation[6 + i];
/* use length + 2 for adding minus sign if needed */
str = devm_kzalloc(regmap_get_device(st->map),
strlen(orient) + 2, GFP_KERNEL);
if (str == NULL)
return -ENOMEM;
if (strcmp(orient, "0") == 0) {
strcpy(str, orient);
} else if (orient[0] == '-') {
strcpy(str, &orient[1]);
} else {
str[0] = '-';
strcpy(&str[1], orient);
}
st->magn_orient.rotation[6 + i] = str;
}
break;
default:
st->magn_orient = st->orientation;
break;
}
return 0;
}
/**
* inv_mpu_magn_read() - read magnetometer data
* @st: driver internal state
* @axis: IIO modifier axis value
* @val: store corresponding axis value
*
* Returns 0 on success, a negative error code otherwise
*/
int inv_mpu_magn_read(const struct inv_mpu6050_state *st, int axis, int *val)
{
unsigned int user_ctrl, status;
__be16 data[3];
uint8_t addr;
uint8_t d;
unsigned int period_ms;
int ret;
/* quit if chip is not supported */
if (!inv_magn_supported(st))
return -ENODEV;
/* Mag data: X - Y - Z */
switch (axis) {
case IIO_MOD_X:
addr = 0;
break;
case IIO_MOD_Y:
addr = 1;
break;
case IIO_MOD_Z:
addr = 2;
break;
default:
return -EINVAL;
}
/* set sample rate to max mag freq */
d = INV_MPU6050_FIFO_RATE_TO_DIVIDER(INV_MPU_MAGN_FREQ_HZ_MAX);
ret = regmap_write(st->map, st->reg->sample_rate_div, d);
if (ret)
return ret;
/* start i2c master, wait for xfer, stop */
user_ctrl = st->chip_config.user_ctrl | INV_MPU6050_BIT_I2C_MST_EN;
ret = regmap_write(st->map, st->reg->user_ctrl, user_ctrl);
if (ret)
return ret;
/* need to wait 2 periods + half-period margin */
period_ms = 1000 / INV_MPU_MAGN_FREQ_HZ_MAX;
msleep(period_ms * 2 + period_ms / 2);
user_ctrl = st->chip_config.user_ctrl;
ret = regmap_write(st->map, st->reg->user_ctrl, user_ctrl);
if (ret)
return ret;
/* restore sample rate */
d = st->chip_config.divider;
ret = regmap_write(st->map, st->reg->sample_rate_div, d);
if (ret)
return ret;
/* check i2c status and read raw data */
ret = regmap_read(st->map, INV_MPU6050_REG_I2C_MST_STATUS, &status);
if (ret)
return ret;
if (status & INV_MPU6050_BIT_I2C_SLV0_NACK ||
status & INV_MPU6050_BIT_I2C_SLV1_NACK)
return -EIO;
ret = regmap_bulk_read(st->map, INV_MPU6050_REG_EXT_SENS_DATA,
data, sizeof(data));
if (ret)
return ret;
*val = (int16_t)be16_to_cpu(data[addr]);
return IIO_VAL_INT;
}

View File

@ -0,0 +1,36 @@
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2019 TDK-InvenSense, Inc.
*/
#ifndef INV_MPU_MAGN_H_
#define INV_MPU_MAGN_H_
#include <linux/kernel.h>
#include "inv_mpu_iio.h"
int inv_mpu_magn_probe(struct inv_mpu6050_state *st);
/**
* inv_mpu_magn_get_scale() - get magnetometer scale value
* @st: driver internal state
*
* Returns IIO data format.
*/
static inline int inv_mpu_magn_get_scale(const struct inv_mpu6050_state *st,
const struct iio_chan_spec *chan,
int *val, int *val2)
{
*val = 0;
*val2 = st->magn_raw_to_gauss[chan->address];
return IIO_VAL_INT_PLUS_MICRO;
}
int inv_mpu_magn_set_rate(const struct inv_mpu6050_state *st, int fifo_rate);
int inv_mpu_magn_set_orient(struct inv_mpu6050_state *st);
int inv_mpu_magn_read(const struct inv_mpu6050_state *st, int axis, int *val);
#endif /* INV_MPU_MAGN_H_ */