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Message-ID: <CAPV97ydLjdGoNYVO+Rmh-whvBE1k7U=dVOuWWni4jnZfXUgBPw@mail.gmail.com>
Date: Tue, 26 Jul 2016 17:22:36 -0700
From: navin patidar <navin.patidar@...il.com>
To: Peter Meerwald-Stadler <pmeerw@...erw.net>
Cc: linux-iio@...r.kernel.org, jic23@...nel.org, knaack.h@....de,
lars@...afoo.de, linux-kernel@...r.kernel.org,
Vlad Dogaru <vlad.dogaru@...el.com>
Subject: Re: [PATCH] iio: orientation: Add BNO055 9-axis Absolute Orientation
Sensor driver
Oh, I didn't know that Vlad already have submitted a patch for BNO055.
My patch doesn't do any thing new so please drop my patch.
regards,
--navin-patidar
On Tue, Jul 26, 2016 at 11:46 AM, Peter Meerwald-Stadler
<pmeerw@...erw.net> wrote:
> 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@...erw.net>
>> wrote:
>>
>> >
>> > > BNO055 provides the following motion sensors data:
>> > >
>> > > * Gyroscope
>> > > * Accelerometer
>> > > * Magnetometer
>> > > * Absolute Orientation (Quaternion)
>> >
>> > comments below
>> >
>> > > Signed-off-by: navin patidar <navin.patidar@...il.com>
>> > > ---
>> > > 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@...il.com>");
>> > > +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)
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