On Fri, 2018-08-31 at 17:35 +0200, Tomasz Duszynski wrote:
> On Thu, Aug 30, 2018 at 10:18:22PM +0100, Afonso Bordado wrote:
> > FXAS21002C is a 3 axis gyroscope with integrated temperature sensor
> >
> > Signed-off-by: Afonso Bordado <[email protected]>
> > ---
> > Changes in v2
> > - Use ANSI C Comments
> > - Minor cleanups
> > - More dscriptive devicetree bindings
> >
> > drivers/iio/gyro/Kconfig | 11 +
> > drivers/iio/gyro/Makefile | 1 +
> > drivers/iio/gyro/fxas21002c.c | 367
> > ++++++++++++++++++++++++++++++++++
> > 3 files changed, 379 insertions(+)
> > create mode 100644 drivers/iio/gyro/fxas21002c.c
> >
> > diff --git a/drivers/iio/gyro/Kconfig b/drivers/iio/gyro/Kconfig
> > index 3126cf05e6b9..d71e33ea9fa4 100644
> > --- a/drivers/iio/gyro/Kconfig
> > +++ b/drivers/iio/gyro/Kconfig
> > @@ -73,6 +73,17 @@ config BMG160_SPI
> > tristate
> > select REGMAP_SPI
> >
> > +config FXAS21002C
> > + tristate "Freescale FXAS21002C Gyroscope"
> > + depends on I2C
> > + select REGMAP_I2C
> > + help
> > + Say yes here to build support for the Freescale FXAS21002C
> > Gyroscope
> > + driver connected via I2C.
> > +
> > + This driver can also be built as a module. If so, the module
> > + will be called fxas21002c.
> > +
> > config HID_SENSOR_GYRO_3D
> > depends on HID_SENSOR_HUB
> > select IIO_BUFFER
> > diff --git a/drivers/iio/gyro/Makefile b/drivers/iio/gyro/Makefile
> > index 295ec780c4eb..ec3e2aeae92a 100644
> > --- a/drivers/iio/gyro/Makefile
> > +++ b/drivers/iio/gyro/Makefile
> > @@ -12,6 +12,7 @@ obj-$(CONFIG_ADXRS450) += adxrs450.o
> > obj-$(CONFIG_BMG160) += bmg160_core.o
> > obj-$(CONFIG_BMG160_I2C) += bmg160_i2c.o
> > obj-$(CONFIG_BMG160_SPI) += bmg160_spi.o
> > +obj-$(CONFIG_FXAS21002C) += fxas21002c.o
> >
> > obj-$(CONFIG_HID_SENSOR_GYRO_3D) += hid-sensor-gyro-3d.o
> >
> > diff --git a/drivers/iio/gyro/fxas21002c.c
> > b/drivers/iio/gyro/fxas21002c.c
> > new file mode 100644
> > index 000000000000..261b73629544
> > --- /dev/null
> > +++ b/drivers/iio/gyro/fxas21002c.c
> > @@ -0,0 +1,367 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * FXAS21002C - Digital Angular Rate Gyroscope driver
> > + *
> > + * Copyright (c) 2018, Afonso Bordado <[email protected]>
> > + *
> > + * IIO driver for FXAS21002C (7-bit I2C slave address 0x20 or
> > 0x21).
> > + * Datasheet: https://www.nxp.com/docs/en/data-sheet/FXAS21002.pdf
> > + * TODO:
> > + * ODR / Scale Support
> > + * Devicetree
> > + * Power management
> > + * LowPass/HighPass Filters
> > + * Buffers
> > + * Interrupts
> > + * Alarms
> > + */
> > +
> > +#include <linux/module.h>
> > +#include <linux/i2c.h>
> > +#include <linux/iio/iio.h>
> > +#include <linux/iio/sysfs.h>
> > +#include <linux/regmap.h>
> > +
> > +#define FXAS21002C_DRV_NAME "fxas21002c"
> > +
> > +#define FXAS21002C_MAX_TRANSITION_TIME_MS 61
> > +
> > +#define FXAS21002C_CHIP_ID 0xD7
> > +
> > +#define FXAS21002C_REG_STATUS 0x00
> > +#define FXAS21002C_REG_OUT_X_MSB 0x01
> > +#define FXAS21002C_REG_OUT_X_LSB 0x02
> > +#define FXAS21002C_REG_OUT_Y_MSB 0x03
> > +#define FXAS21002C_REG_OUT_Y_LSB 0x04
> > +#define FXAS21002C_REG_OUT_Z_MSB 0x05
> > +#define FXAS21002C_REG_OUT_Z_LSB 0x06
> > +#define FXAS21002C_REG_DR_STATUS 0x07
> > +#define FXAS21002C_REG_F_STATUS 0x08
> > +#define FXAS21002C_REG_F_SETUP 0x09
> > +#define FXAS21002C_REG_F_EVENT 0x0A
> > +#define FXAS21002C_REG_INT_SRC_FLAG 0x0B
> > +#define FXAS21002C_REG_WHO_AM_I 0x0C
> > +#define FXAS21002C_REG_CTRL_REG0 0x0D
> > +#define FXAS21002C_REG_RT_CFG 0x0E
> > +#define FXAS21002C_REG_RT_SRC 0x0F
> > +#define FXAS21002C_REG_RT_THS 0x10
> > +#define FXAS21002C_REG_RT_COUNT 0x11
> > +#define FXAS21002C_REG_TEMP 0x12
> > +
> > +#define FXAS21002C_REG_CTRL_REG1 0x13
> > +#define FXAS21002C_RST_BIT BIT(6)
> > +#define FXAS21002C_ACTIVE_BIT BIT(1)
> > +#define FXAS21002C_READY_BIT BIT(0)
> > +
> > +#define FXAS21002C_REG_CTRL_REG2 0x14
> > +#define FXAS21002C_REG_CTRL_REG3 0x15
> > +
> > +#define FXAS21002C_DEFAULT_ODR_HZ 800
> > +
> > +/* 0.0625 deg/s */
> > +#define FXAS21002C_DEFAULT_SENSITIVITY IIO_DEGREE_TO_RAD(62500)
> > +
> > +#define FXAS21002C_TEMP_SCALE 1000
> > +
> > +enum fxas21002c_id {
>
> It looks like your are not using this named enum anywhere
> in the code so perhaps drop the name. Besides the name
> collides with i2c_device_id table's name. Just a suggestion though.
I agree, changed in v3.
> > + ID_FXAS21002C,
> > +};
> > +
> > +enum fxas21002c_operating_mode {
> > + FXAS21002C_OM_BOOT,
> > + FXAS21002C_OM_STANDBY,
> > + FXAS21002C_OM_READY,
> > + FXAS21002C_OM_ACTIVE,
> > +};
> > +
> > +struct fxas21002c_data {
> > + struct i2c_client *client;
> > + struct regmap *regmap;
> > +};
> > +
> > +static const struct regmap_range fxas21002c_writable_ranges[] = {
> > + regmap_reg_range(FXAS21002C_REG_F_SETUP,
> > FXAS21002C_REG_F_SETUP),
> > + regmap_reg_range(FXAS21002C_REG_CTRL_REG0,
> > FXAS21002C_REG_RT_CFG),
> > + regmap_reg_range(FXAS21002C_REG_RT_THS,
> > FXAS21002C_REG_RT_COUNT),
> > + regmap_reg_range(FXAS21002C_REG_CTRL_REG1,
> > FXAS21002C_REG_CTRL_REG3),
> > +};
> > +
> > +static const struct regmap_access_table fxas21002c_writable_table
> > = {
> > + .yes_ranges = fxas21002c_writable_ranges,
> > + .n_yes_ranges = ARRAY_SIZE(fxas21002c_writable_ranges),
> > +};
> > +
> > +static const struct regmap_range fxas21002c_volatile_ranges[] = {
> > + regmap_reg_range(FXAS21002C_REG_STATUS,
> > FXAS21002C_REG_F_STATUS),
> > + regmap_reg_range(FXAS21002C_REG_F_EVENT,
> > FXAS21002C_REG_INT_SRC_FLAG),
> > + regmap_reg_range(FXAS21002C_REG_RT_COUNT,
> > FXAS21002C_REG_CTRL_REG1),
> > +};
> > +
> > +static const struct regmap_access_table fxas21002c_volatile_table
> > = {
> > + .yes_ranges = fxas21002c_volatile_ranges,
> > + .n_yes_ranges = ARRAY_SIZE(fxas21002c_volatile_ranges),
> > +};
> > +
> > +const struct regmap_config fxas21002c_regmap_config = {
> > + .reg_bits = 8,
> > + .val_bits = 8,
> > +
> > + .max_register = FXAS21002C_REG_CTRL_REG3,
> > + /* We don't specify a .rd_table because everything is readable
> > */
> > + .wr_table = &fxas21002c_writable_table,
> > + .volatile_table = &fxas21002c_volatile_table,
> > +};
> > +EXPORT_SYMBOL(fxas21002c_regmap_config);
> > +
> > +#define FXAS21002C_GYRO_CHAN(_axis) {
> > \
> > + .type = IIO_ANGL_VEL,
> > \
> > + .modified = 1,
> > \
> > + .channel2 = IIO_MOD_ ## _axis,
> > \
> > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> > \
> > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |
> > \
> > + BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> > + .address = FXAS21002C_REG_OUT_ ## _axis ## _MSB, \
> > +}
> > +
> > +static const struct iio_chan_spec fxas21002c_channels[] = {
> > + {
> > + .type = IIO_TEMP,
> > + .address = FXAS21002C_REG_TEMP,
> > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> > + BIT(IIO_CHAN_INFO_SCALE),
> > + },
> > + FXAS21002C_GYRO_CHAN(X),
> > + FXAS21002C_GYRO_CHAN(Y),
> > + FXAS21002C_GYRO_CHAN(Z),
> > + IIO_CHAN_SOFT_TIMESTAMP(3),
> > +};
> > +
> > +static int fxas21002c_set_operating_mode(struct fxas21002c_data
> > *data,
> > + enum fxas21002c_operating_mode
> > om)
> > +{
> > + int ret;
> > + int mask;
> > +
> > + switch (om) {
> > + case FXAS21002C_OM_STANDBY:
> > + mask = 0;
> > + break;
> > + case FXAS21002C_OM_READY:
> > + mask = FXAS21002C_READY_BIT;
> > + break;
> > + case FXAS21002C_OM_ACTIVE:
> > + mask = FXAS21002C_ACTIVE_BIT;
> > + break;
> > +
> > + default:
> > + return -EINVAL;
> > + }
> > +
> > + ret = regmap_write(data->regmap, FXAS21002C_REG_CTRL_REG1,
> > mask);
> > + if (ret) {
> > + dev_err(&data->client->dev,
> > + "could not switch operating mode\n");
> > + return ret;
> > + }
> > +
> > + msleep(FXAS21002C_MAX_TRANSITION_TIME_MS);
> > +
> > + return 0;
> > +}
> > +
> > +static void fxas21002c_standby(void *_data)
> > +{
> > + struct fxas21002c_data *data = _data;
> > +
> > + fxas21002c_set_operating_mode(data, FXAS21002C_OM_STANDBY);
> > +}
> > +
> > +static int fxas21002c_reset(struct fxas21002c_data *data)
> > +{
> > + int ret;
> > +
> > + /*
> > + * On issuing a Software Reset command over an I2C interface,
> > + * the device immediately resets and does not send any
> > + * acknowledgment (ACK) of the written byte to the Master.
> > + *
> > + * This is documented in table 46 on the datasheet. Due to this
> > + * the write will fail with EREMOTEIO.
> > + */
> > + ret = regmap_write(data->regmap,
> > + FXAS21002C_REG_CTRL_REG1,
> > FXAS21002C_RST_BIT);
> > +
> > + if (ret != -EREMOTEIO) {
> > + dev_err(&data->client->dev, "could not reset
> > device\n");
> > + return ret;
> > + }
> > +
> > + regcache_mark_dirty(data->regmap);
> > +
> > + /* Wait for device to boot up */
> > + msleep(FXAS21002C_MAX_TRANSITION_TIME_MS);
> > +
> > + return 0;
> > +}
> > +
> > +static int fxas21002c_verify_chip(struct fxas21002c_data *data)
> > +{
> > + int ret;
> > + int chip_id;
> > +
> > + ret = regmap_read(data->regmap, FXAS21002C_REG_WHO_AM_I,
> > &chip_id);
> > + if (ret) {
> > + dev_err(&data->client->dev, "could not read device
> > id\n");
> > + return ret;
> > + }
> > +
> > + if (chip_id != FXAS21002C_CHIP_ID) {
> > + dev_err(&data->client->dev,
> > + "unsupported chip id %02x\n", chip_id);
> > + return -ENODEV;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int fxas21002c_read_oneshot(struct fxas21002c_data *data,
> > + struct iio_chan_spec const *chan,
> > int *val)
> > +{
> > + int ret;
> > + __be16 bulk_raw;
> > +
> > + switch (chan->type) {
> > + case IIO_ANGL_VEL:
> > + ret = regmap_bulk_read(data->regmap, chan->address,
> > + &bulk_raw, sizeof(bulk_raw));
> > + if (ret)
> > + return ret;
> > +
> > + *val = sign_extend32(be16_to_cpu(bulk_raw), 15);
> > + return IIO_VAL_INT;
> > + case IIO_TEMP:
> > + ret = regmap_read(data->regmap, chan->address, val);
> > + if (ret)
> > + return ret;
> > +
> > + return IIO_VAL_INT;
> > + default:
> > + return -EINVAL;
> > + }
> > +}
> > +
> > +static int fxas21002c_read_raw(struct iio_dev *indio_dev,
> > + struct iio_chan_spec const *chan, int
> > *val,
> > + int *val2, long mask)
> > +{
> > + struct fxas21002c_data *data = iio_priv(indio_dev);
> > +
> > + switch (mask) {
> > + case IIO_CHAN_INFO_RAW:
> > + return fxas21002c_read_oneshot(data, chan, val);
> > + case IIO_CHAN_INFO_SCALE:
> > + switch (chan->type) {
> > + case IIO_ANGL_VEL:
> > + *val = 0;
> > + *val2 = FXAS21002C_DEFAULT_SENSITIVITY;
> > +
> > + return IIO_VAL_INT_PLUS_MICRO;
> > + case IIO_TEMP:
> > + *val = FXAS21002C_TEMP_SCALE;
> > +
> > + return IIO_VAL_INT;
> > + default:
> > + return -EINVAL;
> > + }
> > + case IIO_CHAN_INFO_SAMP_FREQ:
> > + if (chan->type != IIO_ANGL_VEL)
> > + return -EINVAL;
> > +
> > + *val = FXAS21002C_DEFAULT_ODR_HZ;
> > +
> > + return IIO_VAL_INT;
> > + }
> > +
> > + return -EINVAL;
> > +}
> > +
> > +static const struct iio_info fxas21002c_info = {
> > + .read_raw = fxas21002c_read_raw,
> > +};
> > +
> > +static int fxas21002c_probe(struct i2c_client *client,
> > + const struct i2c_device_id *id)
> > +{
> > + int ret;
> > + struct iio_dev *indio_dev;
> > + struct fxas21002c_data *data;
> > +
> > + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> > + if (!indio_dev)
> > + return -ENOMEM;
> > +
> > + i2c_set_clientdata(client, indio_dev);
> > + data = iio_priv(indio_dev);
> > + data->client = client;
> > +
> > + data->regmap = devm_regmap_init_i2c(client,
> > &fxas21002c_regmap_config);
> > + if (IS_ERR(data->regmap)) {
> > + ret = PTR_ERR(data->regmap);
> > + dev_err(&client->dev,
> > + "Failed to allocate regmap, err: %d\n", ret);
> > + return ret;
> > + }
> > +
> > + indio_dev->dev.parent = &client->dev;
> > + indio_dev->channels = fxas21002c_channels;
> > + indio_dev->num_channels = ARRAY_SIZE(fxas21002c_channels);
> > + indio_dev->name = id->name;
> > + indio_dev->modes = INDIO_DIRECT_MODE;
> > + indio_dev->info = &fxas21002c_info;
> > +
> > + ret = fxas21002c_verify_chip(data);
> > + if (ret < 0)
> > + return ret;
> > +
> > + ret = fxas21002c_reset(data);
> > + if (ret < 0)
> > + return ret;
> > +
> > + ret = fxas21002c_set_operating_mode(data,
> > FXAS21002C_OM_ACTIVE);
> > + if (ret < 0)
> > + return ret;
> > +
> > + ret = devm_add_action(&client->dev, fxas21002c_standby, data);
> > + if (ret < 0) {
> > + fxas21002c_standby(data);
> > + dev_err(&client->dev, "failed to add standby
> > action\n");
> > + return ret;
> > + }
> > +
> > + ret = iio_device_register(indio_dev);
> > + if (ret < 0)
> > + dev_err(&client->dev, "failed to register iio
> > device\n");
> > +
> > + return ret;
> > +}
> > +
> > +static const struct i2c_device_id fxas21002c_id[] = {
> > + {"fxas21002c", ID_FXAS21002C},
> > + {}
> > +};
> > +
> > +MODULE_DEVICE_TABLE(i2c, fxas21002c_id);
> > +
> > +static struct i2c_driver fxas21002c_driver = {
> > + .driver = {
> > + .name = FXAS21002C_DRV_NAME,
> > + },
> > + .probe = fxas21002c_probe,
> > + .id_table = fxas21002c_id,
> > +};
> > +
> > +module_i2c_driver(fxas21002c_driver);
> > +
> > +MODULE_AUTHOR("Afonso Bordado <[email protected]>");
> > +MODULE_DESCRIPTION("FXAS21002C Digital Angular Rate Gyroscope
> > driver");
> > +MODULE_LICENSE("GPL v2");
> > --
> > 2.18.0
> >
> >
