Re: [PATCH] iio: orientation: Add BNO055 9-axis Absolute Orientation Sensor driver

From: Peter Meerwald-Stadler
Date: Tue Jul 26 2016 - 14:47:09 EST


Hallo Navin,

> Thanks for reviewing the patch. I will send the updated patch.

I am sorry to have overlooked a previous patch by Vlad Dogaru, see
http://comments.gmane.org/gmane.linux.kernel.iio/24643, for the BNO055

there have been a number of issues, it has not been accepted yet

I think our policy is first come, first served; I have compared the two
patches, maybe you can collaborate on a common proposal?

regards, p.

> regards,
> --navin-patidar
>
> On Tue, Jul 26, 2016 at 1:07 AM, Peter Meerwald-Stadler <pmeerw@xxxxxxxxxx>
> wrote:
>
> >
> > > BNO055 provides the following motion sensors data:
> > >
> > > * Gyroscope
> > > * Accelerometer
> > > * Magnetometer
> > > * Absolute Orientation (Quaternion)
> >
> > comments below
> >
> > > Signed-off-by: navin patidar <navin.patidar@xxxxxxxxx>
> > > ---
> > > drivers/iio/orientation/Kconfig | 10 +
> > > drivers/iio/orientation/Makefile | 1 +
> > > drivers/iio/orientation/bno055.c | 422
> > +++++++++++++++++++++++++++++++++++++++
> > > 3 files changed, 433 insertions(+)
> > > create mode 100644 drivers/iio/orientation/bno055.c
> > >
> > > diff --git a/drivers/iio/orientation/Kconfig
> > b/drivers/iio/orientation/Kconfig
> > > index e3aa1e5..9ac21ee 100644
> > > --- a/drivers/iio/orientation/Kconfig
> > > +++ b/drivers/iio/orientation/Kconfig
> > > @@ -28,4 +28,14 @@ config HID_SENSOR_DEVICE_ROTATION
> > > device rotation. The output of a device rotation sensor
> > > is presented using quaternion format.
> > >
> > > +config BNO055
> > > + tristate "BOSCH BNO055 Absolute Orientation"
> > > + depends on I2C
> > > + select REGMAP_I2C
> > > + help
> > > + Say yes here to build support for BOSCH BNO55 9-axis absolute
> > orientation sensor
> > > + driver connected via I2C.
> > > + This driver can also be built as a module. If so, the module
> > > + will be called bno055.
> > > +
> > > endmenu
> > > diff --git a/drivers/iio/orientation/Makefile
> > b/drivers/iio/orientation/Makefile
> > > index 4734dab..7d00037 100644
> > > --- a/drivers/iio/orientation/Makefile
> > > +++ b/drivers/iio/orientation/Makefile
> > > @@ -5,3 +5,4 @@
> > > # When adding new entries keep the list in alphabetical order
> > > obj-$(CONFIG_HID_SENSOR_INCLINOMETER_3D) += hid-sensor-incl-3d.o
> > > obj-$(CONFIG_HID_SENSOR_DEVICE_ROTATION) += hid-sensor-rotation.o
> > > +obj-$(CONFIG_BNO055) += bno055.o
> > > diff --git a/drivers/iio/orientation/bno055.c
> > b/drivers/iio/orientation/bno055.c
> > > new file mode 100644
> > > index 0000000..48b9e93
> > > --- /dev/null
> > > +++ b/drivers/iio/orientation/bno055.c
> > > @@ -0,0 +1,422 @@
> > > +/*
> > > + * Copyright (c) 2016 Intel Corporation
> > > + *
> > > + * Driver for Bosch Sensortec BNO055 digital motion sensor.
> > > + *
> > > + * This program is free software; you can redistribute it and/or modify
> > > + * it under the terms of the GNU General Public License version 2 as
> > > + * published by the Free Software Foundation.
> > > + *
> >
> > I find it useful to state the 7-bit i2c chip address here
> >
> > > + */
> > > +
> > > +#define pr_fmt(fmt) "bno055: " fmt
> > > +
> > > +#include <linux/module.h>
> > > +#include <linux/i2c.h>
> > > +#include <linux/acpi.h>
> > > +#include <linux/regmap.h>
> > > +#include <linux/iio/iio.h>
> > > +#include <linux/iio/sysfs.h>
> > > +
> >
> > drop one newline
> >
> > > +
> > > +#define BNO055_CHIP_ID 0xA0
> > > +#define REG_MAG_RADIUS_MSB 0x6A
> >
> > please consistently prefix with BNO055_
> >
> > > +
> > > +/* BNO055 configuration registers */
> > > +#define REG_PWR_MODE 0x3E
> > > +#define REG_OPR_MODE 0x3D
> > > +#define REG_UNIT_SEL 0x3B
> > > +#define REG_AXIS_MAP_SIGN 0x42
> > > +#define REG_AXIS_MAP_CONFIG 0x41
> > > +#define REG_UNIT_SEL 0x3B
> > > +#define REG_SYS_TRIGGER 0x3F
> > > +#define BNO055_REG_PAGE_ID 0x07
> > > +#define BNO055_REG_ID 0x00
> > > +
> > > +/* BNO055 status registers */
> > > +#define SYS_STATUS 0x39
> > > +#define INT_STATUS 0x37
> > > +#define CALIB_STATUS 0x35
> > > +
> > > +/* BNO055 data registers */
> >
> > drop newline
> >
> > > +
> > > +#define GRV_DATA_Z_MSB 0x33
> > > +#define GRV_DATA_Z_LSB 0x32
> > > +#define GRV_DATA_Y_MSB 0x31
> > > +#define GRV_DATA_Y_LSB 0x30
> > > +#define GRV_DATA_X_MSB 0x2F
> > > +#define GRV_DATA_X_LSB 0x2E
> >
> > do we really need all those register #defines?
> > they are not used and noone wants to read just the LSB...
> >
> > > +
> > > +#define LIA_DATA_Z_MSB 0x2D
> > > +#define LIA_DATA_Z_LSB 0x2C
> > > +#define LIA_DATA_Y_MSB 0x2B
> > > +#define LIA_DATA_Y_LSB 0x2A
> > > +#define LIA_DATA_X_MSB 0x29
> > > +#define LIA_DATA_X_LSB 0x28
> > > +
> > > +#define QUA_DATA_Z_MSB 0x27
> > > +#define QUA_DATA_Z_LSB 0x26
> > > +#define QUA_DATA_Y_MSB 0x25
> > > +#define QUA_DATA_Y_LSB 0x24
> > > +#define QUA_DATA_X_MSB 0x23
> > > +#define QUA_DATA_X_LSB 0x22
> > > +#define QUA_DATA_W_MSB 0x21
> > > +#define QUA_DATA_W_LSB 0x20
> > > +
> > > +#define EUL_PITCH_MSB 0x1F
> > > +#define EUL_PITCH_LSB 0x1E
> > > +#define EUL_ROLL_MSB 0x1D
> > > +#define EUL_ROLL_LSB 0x1C
> > > +#define EUL_HEADING_MSB 0x1B
> > > +#define EUL_HEADING_LSB 0x1A
> > > +
> > > +#define GYR_DATA_Z_MSB 0x19
> > > +#define GYR_DATA_Z_LSB 0x18
> > > +#define GYR_DATA_Y_MSB 0x17
> > > +#define GYR_DATA_Y_LSB 0x16
> > > +#define GYR_DATA_X_MSB 0x15
> > > +#define GYR_DATA_X_LSB 0x14
> > > +
> > > +#define MAG_DATA_Z_MSB 0x13
> > > +#define MAG_DATA_Z_LSB 0x12
> > > +#define MAG_DATA_Y_MSB 0x11
> > > +#define MAG_DATA_Y_LSB 0x10
> > > +#define MAG_DATA_X_MSB 0x0F
> > > +#define MAG_DATA_X_LSB 0x0E
> > > +
> > > +#define ACC_DATA_Z_MSB 0x0D
> > > +#define ACC_DATA_Z_LSB 0x0C
> > > +#define ACC_DATA_Y_MSB 0x0B
> > > +#define ACC_DATA_Y_LSB 0x0A
> > > +#define ACC_DATA_X_MSB 0x09
> > > +#define ACC_DATA_X_LSB 0x08
> > > +
> > > +/* operation modes */
> > > +#define FUSION_NDOF_MODE 0x0C
> > > +
> > > +/* power modes */
> > > +#define NORMAL_MODE 0x00
> > > +#define LOW_POWER_MODE BIT(0)
> > > +#define SUSPEND_MODE BIT(1)
> > > +
> > > +#define PROPER_CALIBRATION 0xFF
> > > +
> > > +#define BASE_REG 0x08
> > > +#define SENSOR_AXIS_TO_REG(sensor,axis) (BASE_REG + (sensor * 6) +
> > (axis * 2))
> > > +
> > > +#define BNO055_CHANNEL(_type, _axis) {
> > \
> > > + .type = IIO_##_type, \
> > > + .modified = 1, \
> > > + .channel2 = IIO_MOD_##_axis, \
> > > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> >
> > in what unit is the data returned; please check with IIO ABI documentation
> > I think you will likely need _SCALE for some channels
> >
> > > + .scan_index = AXIS_##_axis, \
> >
> > .scan_index is a continuous counter over ALL channels, not just for one
> > channel type
> >
> > the driver does not support buffered reads, so not scan_type/scan_index is
> > needed anyway
> >
> > > + .scan_type = { \
> > > + .sign = 's', \
> > > + .realbits = 16, \
> > > + .storagebits = 16, \
> > > + .endianness = IIO_LE, \
> > > + }, \
> > > +}
> > > +
> > > +struct bno055_data {
> > > + struct i2c_client *client;
> > > + struct mutex lock;
> > > + struct regmap *regmap;
> > > +};
> > > +
> > > +enum bno055_axis {
> > > + AXIS_X,
> > > + AXIS_Y,
> > > + AXIS_Z,
> > > +};
> > > +
> > > +enum {ACC=0, MAG=1, GYR=2, EUL=3, QUA=4};
> >
> > prefix!
> >
> > > +
> > > +static const struct iio_chan_spec bno055_channels[] = {
> > > + BNO055_CHANNEL(ANGL_VEL, X),
> > > + BNO055_CHANNEL(ANGL_VEL, Y),
> > > + BNO055_CHANNEL(ANGL_VEL, Z),
> > > + BNO055_CHANNEL(MAGN, X),
> > > + BNO055_CHANNEL(MAGN, Y),
> > > + BNO055_CHANNEL(MAGN, Z),
> > > + BNO055_CHANNEL(ACCEL, X),
> > > + BNO055_CHANNEL(ACCEL, Y),
> > > + BNO055_CHANNEL(ACCEL, Z),
> > > + {
> > > + .type = IIO_ROT,
> > > + .modified = 1,
> > > + .channel2 = IIO_MOD_QUATERNION,
> > > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> > > + }
> > > +};
> > > +
> > > +static bool bno055_is_writeable_reg(struct device *dev, unsigned int
> > reg)
> > > +{
> > > + switch (reg) {
> > > + case REG_PWR_MODE:
> > > + case REG_OPR_MODE:
> > > + case REG_UNIT_SEL:
> > > + case REG_AXIS_MAP_SIGN:
> > > + case REG_AXIS_MAP_CONFIG:
> > > + case REG_SYS_TRIGGER:
> > > + return true;
> > > + default:
> > > + return false;
> > > + };
> > > +}
> > > +
> > > +static bool bno055_is_volatile_reg(struct device *dev, unsigned int reg)
> > > +{
> > > + if ((reg >= ACC_DATA_X_LSB) && (reg <= QUA_DATA_Z_MSB))
> > > + return true;
> > > + else
> > > + return false;
> > > +}
> > > +
> > > +static const struct regmap_config bno055_regmap_config = {
> > > + .reg_bits = 8,
> > > + .val_bits = 8,
> > > +
> > > + .max_register = REG_MAG_RADIUS_MSB,
> > > + .cache_type = REGCACHE_RBTREE,
> > > +
> > > + .writeable_reg = bno055_is_writeable_reg,
> > > + .volatile_reg = bno055_is_volatile_reg,
> > > +};
> > > +
> >
> > drop newline
> >
> > > +
> > > +static int read_bno055(struct bno055_data *data, int sensor, int axis,
> > int *val)
> >
> > bno055 prefix please
> >
> > > +{
> > > + int ret;
> > > + __le16 raw_val;
> > > + int reg;
> > > +
> > > + reg = SENSOR_AXIS_TO_REG(sensor, axis);
> >
> > you can use .address in channel spec for that
> >
> > > +
> > > + ret = regmap_bulk_read(data->regmap, reg, &raw_val,
> > > + sizeof(raw_val));
> > > + if (ret < 0) {
> > > + dev_err(&data->client->dev, "Error reading axis %d\n",
> > axis);
> > > + return ret;
> > > + }
> > > +
> > > + *val = sign_extend32(le16_to_cpu(raw_val), 15);
> > > + return IIO_VAL_INT;
> > > +}
> > > +
> > > +/* Read raw quaternion values W,X,Y and Z.
> > > + * Raw values needs to be divied by the 16384 to get the exact
> > quaternion values.
> > > + */
> > > +
> > > +static int read_rot(struct bno055_data *data, int *vals, int *val_len)
> > > +{
> > > + int ret, i;
> > > + __le16 raw_val[4];
> > > +
> > > + ret = regmap_bulk_read(data->regmap, QUA_DATA_W_LSB, &raw_val,
> > > + sizeof(raw_val));
> > > + if (ret < 0) {
> > > + dev_err(&data->client->dev, "Error reading Orientation
> > \n");
> >
> > lowercase orientation
> > delete space before \n
> >
> > > + return ret;
> > > + }
> > > +
> > > + for (i = 0; i < 4; ++i)
> > > + vals[i] = sign_extend32(le16_to_cpu(raw_val[i]), 15);
> > > +
> > > + *val_len = 4;
> > > + return IIO_VAL_INT_MULTIPLE;
> > > +}
> > > +
> > > +static int bno055_read_raw_multi(struct iio_dev *indio_dev,
> > > + struct iio_chan_spec const *chan, int size,
> > > + int *val, int *val2, long mask)
> > > +{
> > > + int ret = -EINVAL;
> > > + struct bno055_data *data = iio_priv(indio_dev);
> > > +
> > > + mutex_lock(&data->lock);
> > > +
> > > + switch (mask) {
> > > + case IIO_CHAN_INFO_RAW:
> > > + switch (chan->type) {
> > > + case IIO_ROT:
> > > + ret = read_rot(data, val, val2);
> > > + break;
> > > + case IIO_ANGL_VEL:
> > > + /* Gyroscope unit degrees per second */
> > > + /* Raw value needs to be divied by the 16 to get
> > the exact value.*/
> >
> > comment style, not a proper multi-line comment
> > use _SCALE, it is not about 'exact' but correct scaling/unit
> > typo: divided
> > wording: divided by 16
> >
> > > + ret = read_bno055(data, GYR, chan->scan_index,
> > val);
> > > + break;
> > > + case IIO_ACCEL:
> > > + /* Accelerometer Unit m/s2 */
> > > + /* Raw value needs to be divied by the 100 to get
> > the exact value.*/
> > > + ret = read_bno055(data, ACC, chan->scan_index,
> > val);
> > > + break;
> > > + case IIO_MAGN:
> > > + /* Magnetometer Unit microTesla */
> > > + /* Raw value needs to be divied by the 16 to get
> > the exact value. */
> > > + ret = read_bno055(data, MAG, chan->scan_index,
> > val);
> > > + break;
> > > + default:
> > > + ret = -EINVAL;
> > > + break;
> > > + }
> > > + break;
> > > +
> > > + default:
> > > + ret = -EINVAL;
> > > + break;
> > > + }
> > > +
> > > + mutex_unlock(&data->lock);
> > > +
> > > + return ret;
> > > +}
> > > +
> > > +static const struct iio_info bno055_info = {
> > > + .driver_module = THIS_MODULE,
> > > + .read_raw_multi = &bno055_read_raw_multi,
> > > +};
> > > +
> >
> > drop newline
> >
> > > +
> > > +static int bno055_chip_init(struct bno055_data *data)
> > > +{
> > > + int ret;
> > > +
> > > + ret = regmap_write(data->regmap, REG_PWR_MODE,
> > > + NORMAL_MODE);
> > > + if (ret < 0) {
> > > + dev_err(&data->client->dev,
> > > + "failed to write power mode register\n");
> > > + return ret;
> > > + }
> > > +
> > > + ret = regmap_write(data->regmap, REG_OPR_MODE,
> > > + FUSION_NDOF_MODE);
> > > + if (ret < 0)
> > > + dev_err(&data->client->dev,
> > > + "failed to write operation mode register\n");
> > > +
> > > + return ret;
> > > +}
> > > +
> > > +static ssize_t show_calibration_status(struct device *dev, struct
> > device_attribute *attr,
> > > + char *buf){
> >
> > this is private API which needs to be documented
> >
> > > + struct bno055_data *data;
> > > + int ret;
> > > + unsigned int calib_stat;
> > > +
> > > + data = dev->driver_data;
> > > +
> > > + ret = regmap_read(data->regmap, CALIB_STATUS, &calib_stat);
> > > +
> > > + if (ret){
> >
> > space before {
> >
> > > + dev_err(dev, "Failed to read calibration status.\n");
> > > + return ret;
> > > + }
> > > +
> > > + if (calib_stat != PROPER_CALIBRATION)
> > > + dev_info(dev, "bad calibration. expected %x got %x\n",
> >
> > two spaces before 'expected'
> >
> > > + PROPER_CALIBRATION, calib_stat);
> > > +
> > > + return scnprintf(buf, PAGE_SIZE, "0x%x\n", calib_stat);
> > > +}
> > > +
> > > +static DEVICE_ATTR(calib_status, 0444, show_calibration_status, NULL);
> > > +
> > > +static int bno055_probe(struct i2c_client *client,
> > > + const struct i2c_device_id *id)
> > > +{
> > > + int ret;
> > > + struct iio_dev *indio_dev;
> > > + struct bno055_data *data;
> > > + unsigned int chip_id;
> > > +
> > > + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> > > + if (!indio_dev)
> > > + return -ENOMEM;
> > > +
> > > + data = iio_priv(indio_dev);
> > > + mutex_init(&data->lock);
> > > + data->client = client;
> > > +
> > > + indio_dev->dev.parent = &client->dev;
> > > + indio_dev->name = id->name;
> > > + indio_dev->channels = bno055_channels;
> > > + indio_dev->num_channels = ARRAY_SIZE(bno055_channels);
> > > + indio_dev->info = &bno055_info;
> > > + indio_dev->modes = INDIO_DIRECT_MODE;
> > > +
> > > + data->regmap = devm_regmap_init_i2c(client, &bno055_regmap_config);
> > > + if (IS_ERR(data->regmap)) {
> > > + dev_err(&client->dev, "Failed to allocate register
> > map.\n");
> > > + return PTR_ERR(data->regmap);
> > > + }
> > > +
> > > + indio_dev->dev.driver_data = data;
> > > + i2c_set_clientdata(client, indio_dev);
> > > +
> > > + ret = regmap_read(data->regmap, BNO055_REG_ID, &chip_id);
> > > + if (ret < 0)
> > > + return ret;
> > > + if (chip_id != BNO055_CHIP_ID) {
> > > + dev_err(&client->dev, "bad chip id. expected %x got %x\n",
> > > + BNO055_CHIP_ID, chip_id);
> > > + return -EINVAL;
> > > + }
> > > +
> > > + ret = bno055_chip_init(data);
> > > + if (ret < 0)
> > > + return ret;
> > > +
> > > + ret = devm_iio_device_register(&client->dev, indio_dev);
> > > + if (ret){
> >
> > space before {
> >
> > > + dev_err(&client->dev, "failed to register IIO device.\n");
> > > + return ret;
> > > + }
> > > +
> > > + ret = device_create_file(&indio_dev->dev, &dev_attr_calib_status);
> >
> > needs to be done BEFORE devm_iio_device_register()
> > IIO has specific mechanisms to create custom sysfs entries...
> >
> > > + if (ret){
> >
> > space before {
> >
> > > + dev_err(&client->dev, "failed to create sysfs entry.\n");
> > > + devm_iio_device_unregister(&client->dev, indio_dev);
> >
> > no need to call devm_iio_device_unregister
> >
> > > + return ret;
> > > + }
> > > +
> > > + return ret;
> > > +}
> > > +
> > > +static int bno055_remove(struct i2c_client *client)
> > > +{
> > > + struct iio_dev *indio_dev = i2c_get_clientdata(client);
> > > +
> > > + device_remove_file(&indio_dev->dev, &dev_attr_calib_status);
> > > + devm_iio_device_unregister(&client->dev, indio_dev);
> > > + return 0;
> > > +}
> > > +
> > > +static const struct acpi_device_id bno055_acpi_match[] = {
> > > + {"bno055", 0},
> > > + { },
> > > +};
> > > +MODULE_DEVICE_TABLE(acpi, bno055_acpi_match);
> > > +
> > > +static const struct i2c_device_id bno055_id[] = {
> > > + {"bno055", 0},
> > > + { },
> > > +};
> > > +MODULE_DEVICE_TABLE(i2c, bno055_id);
> > > +
> > > +static struct i2c_driver bno055_driver = {
> > > + .driver = {
> > > + .name = "bno055",
> > > + .acpi_match_table = ACPI_PTR(bno055_acpi_match),
> > > + },
> > > + .probe = bno055_probe,
> > > + .remove = bno055_remove,
> > > + .id_table = bno055_id,
> > > +};
> > > +module_i2c_driver(bno055_driver);
> > > +
> > > +MODULE_AUTHOR("navin patidar <navin.patidar@xxxxxxxxx>");
> > > +MODULE_DESCRIPTION("Driver for Bosch Sensortec BNO055 orientation
> > sensor");
> > > +MODULE_LICENSE("GPL v2");
> > >
> >
> > --
> >
> > Peter Meerwald-Stadler
> > +43-664-2444418 (mobile)
> >
>

--

Peter Meerwald-Stadler
+43-664-2444418 (mobile)