| Message ID | 20180825211910.22929-1-afonsobordado@az8.co (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/4] iio: gyro: add support for fxas21002c | expand |
On Sat, 25 Aug 2018 22:19:07 +0100 Afonso Bordado <afonsobordado@az8.co> wrote: > FXAS21002C is a 3 axis gyroscope with integrated temperature sensor > > Signed-off-by: Afonso Bordado <afonsobordado@az8.co> Hi, Driver is pretty clean so only a few minor comments inline. If we were late in a cycle I'd probably just have taken it and fixed up but as we have lots of time and I'm inherently lazy I'll let you do a v2 :) Good job, thanks! Jonathan > --- > drivers/iio/gyro/Kconfig | 11 ++ > drivers/iio/gyro/Makefile | 1 + > drivers/iio/gyro/fxas21002c.c | 363 ++++++++++++++++++++++++++++++++++ > 3 files changed, 375 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..7626b2f88d72 > --- /dev/null > +++ b/drivers/iio/gyro/fxas21002c.c > @@ -0,0 +1,363 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * FXAS21002C - Digital Angular Rate Gyroscope driver > + * > + * Copyright (c) 2018, Afonso Bordado <afonsobordado@az8.co> > + * > + * 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) > + > +enum fxas21002c_id { > + 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 /* ... */ Please run checkpatch as IIRC it complains about this. > + .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), As it currently stands it is IIO_CHAN_PROCESSED but I'd prefer you provided the scale and kept it as _RAW. > + }, > + 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 = 0; Might be clearer to not set this here and... > + > + switch (om) { > + case FXAS21002C_OM_STANDBY: mask = 0; > + break; > + case FXAS21002C_OM_READY: > + mask |= FXAS21002C_READY_BIT; mask = FXA210002C_READY_BIT; > + break; > + case FXAS21002C_OM_ACTIVE: > + mask |= FXAS21002C_ACTIVE_BIT; mask = FXA21002C_ACTIVE_BIT; Slightly more readable I think... > + 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 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 /* Wait... */ > + 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; > + int raw; > + __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); > + break; return IIO_VAL_INT directly here. > + case IIO_TEMP: > + ret = regmap_read(data->regmap, chan->address, &raw); > + if (ret) > + return ret; > + > + *val = raw * 1000; // Convert to millicelsius Don't use c++ style comments in kernel code please. Also I wouldn't do this multiplier in here, I'd provide the scale attribute. The reason is that we may later have support for buffered reads from this device - at that point we will want to have nice 8 bit data rather than having a scaled value that isn't quite a whole number of bits. > + break; return IIO_VAL_INT; directly here. > + default: > + return -EINVAL; > + } > + With the above two changes in place this return is never reached. > + return IIO_VAL_INT; > +} > + > +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: > + if (chan->type != IIO_ANGL_VEL) > + return -EINVAL; This check is a bit over paranoid given there is no way this would be called in with a different type. Doesn't do any real harm though. > + > + *val = 0; > + *val2 = FXAS21002C_DEFAULT_SENSITIVITY; > + > + return IIO_VAL_INT_PLUS_MICRO; > + 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 = iio_device_register(indio_dev); > + if (ret < 0) { > + dev_err(&client->dev, "Failed to register iio device\n"); > + fxas21002c_set_operating_mode(data, FXAS21002C_OM_STANDBY); > + return ret; We may potentially get a patch as one of the static analysis tools will point out that return ret could be dropped out of the brackets without changing the code (ret is 0 in this case as iio_device_register never returns positive) Really minor though! > + } > + > + return 0; > +} > + > +static int fxas21002c_remove(struct i2c_client *client) > +{ > + struct iio_dev *indio_dev = i2c_get_clientdata(client); > + struct fxas21002c_data *data = iio_priv(indio_dev); > + > + iio_device_unregister(indio_dev); > + > + fxas21002c_set_operating_mode(data, FXAS21002C_OM_STANDBY); You could have used the devm_add_action to allow the managed cleanup to handle this and hence gotten rid of the remove function. (minor suggestion and somewhat a matter of personal taste). > + > + return 0; > +} > + > +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, > + .remove = fxas21002c_remove, > + .id_table = fxas21002c_id, > +}; > + > +module_i2c_driver(fxas21002c_driver); > + > +MODULE_AUTHOR("Afonso Bordado <afonsobordado@az8.co>"); > +MODULE_DESCRIPTION("FXAS21002C Digital Angular Rate Gyroscope driver"); > +MODULE_LICENSE("GPL v2");
On Mon, 2018-08-27 at 18:08 +0100, Jonathan Cameron wrote: > On Sat, 25 Aug 2018 22:19:07 +0100 > Afonso Bordado <afonsobordado@az8.co> wrote: > > > FXAS21002C is a 3 axis gyroscope with integrated temperature sensor > > > > Signed-off-by: Afonso Bordado <afonsobordado@az8.co> > > Hi, > > Driver is pretty clean so only a few minor comments inline. > If we were late in a cycle I'd probably just have taken it and fixed up > but as we have lots of time and I'm inherently lazy I'll let you do a v2 :) > > Good job, thanks! [] > > diff --git a/drivers/iio/gyro/fxas21002c.c b/drivers/iio/gyro/fxas21002c.c [] > /* ... */ > > Please run checkpatch as IIRC it complains about this. Running checkpatch and paying attention to what it bleats is generally a good idea, as long as its bleats aren't mindlessly followed. And c99 style // comments have been ignored since: commit dadf680de3c2eb4cba9840619991eda0cfe98778 Author: Joe Perches <joe@perches.com> Date: Tue Aug 2 14:04:33 2016 -0700 checkpatch: allow c99 style // comments Sanitise the lines that contain c99 comments so that the error doesn't get emitted.
On Mon, 2018-08-27 at 18:08 +0100, Jonathan Cameron wrote: > On Sat, 25 Aug 2018 22:19:07 +0100 > Afonso Bordado <afonsobordado@az8.co> wrote: > > > FXAS21002C is a 3 axis gyroscope with integrated temperature sensor > > > > Signed-off-by: Afonso Bordado <afonsobordado@az8.co> > > Hi, > > Driver is pretty clean so only a few minor comments inline. > If we were late in a cycle I'd probably just have taken it and fixed > up > but as we have lots of time and I'm inherently lazy I'll let you do a > v2 :) > > Good job, thanks! > > Jonathan Great! > > + > > +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 > > /* ... */ > > Please run checkpatch as IIRC it complains about this. I've replaced all instances of C99 comments with ANSI comments. However, has Joe Perches mentioned. Checkpatch did not warn me about this. > > + .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), > > As it currently stands it is IIO_CHAN_PROCESSED but I'd prefer you > provided > the scale and kept it as _RAW. Changed in v2. I'll provide scale + raw. > > + }, > > + 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 = 0; > > Might be clearer to not set this here and... > > + > > + switch (om) { > > + case FXAS21002C_OM_STANDBY: > > mask = 0; > > + break; > > + case FXAS21002C_OM_READY: > > + mask |= FXAS21002C_READY_BIT; > > mask = FXA210002C_READY_BIT; > > + break; > > + case FXAS21002C_OM_ACTIVE: > > + mask |= FXAS21002C_ACTIVE_BIT; > > mask = FXA21002C_ACTIVE_BIT; > > Slightly more readable I think... I Agree. > > +static int fxas21002c_read_oneshot(struct fxas21002c_data *data, > > + struct iio_chan_spec const *chan, > > int *val) > > +{ > > + int ret; > > + int raw; > > + __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); > > + break; > > return IIO_VAL_INT directly here. Sure > > + case IIO_TEMP: > > + ret = regmap_read(data->regmap, chan->address, &raw); > > + if (ret) > > + return ret; > > + > > + *val = raw * 1000; // Convert to millicelsius > > Don't use c++ style comments in kernel code please. > > Also I wouldn't do this multiplier in here, I'd provide the scale > attribute. > The reason is that we may later have support for buffered reads from > this > device - at that point we will want to have nice 8 bit data rather > than having > a scaled value that isn't quite a whole number of bits. This makes sense, I'll put in the SCALE bit for temp. > > + break; > > return IIO_VAL_INT; directly here. > > + default: > > + return -EINVAL; > > + } > > + > > With the above two changes in place this return is never reached. Changed in v2. > > + return IIO_VAL_INT; > > +} > > + > > +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: > > + if (chan->type != IIO_ANGL_VEL) > > + return -EINVAL; > > This check is a bit over paranoid given there is no way > this would be called in with a different type. > > Doesn't do any real harm though. This no longer applies with the temp changes included in v2. However, i'd still like to leave it for IIO_CHAN_INFO_SAMP_FREQ. > > + > > + *val = 0; > > + *val2 = FXAS21002C_DEFAULT_SENSITIVITY; > > + > > + return IIO_VAL_INT_PLUS_MICRO; > > + 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 = iio_device_register(indio_dev); > > + if (ret < 0) { > > + dev_err(&client->dev, "Failed to register iio > > device\n"); > > + fxas21002c_set_operating_mode(data, > > FXAS21002C_OM_STANDBY); > > + return ret; > > We may potentially get a patch as one of the static analysis tools > will point > out that return ret could be dropped out of the brackets without > changing the > code (ret is 0 in this case as iio_device_register never returns > positive) > > Really minor though! Will be fixed in V2. > > + > > +static int fxas21002c_remove(struct i2c_client *client) > > +{ > > + struct iio_dev *indio_dev = i2c_get_clientdata(client); > > + struct fxas21002c_data *data = iio_priv(indio_dev); > > + > > + iio_device_unregister(indio_dev); > > + > > + fxas21002c_set_operating_mode(data, FXAS21002C_OM_STANDBY); > > You could have used the devm_add_action to allow the managed cleanup > to handle > this and hence gotten rid of the remove function. > > (minor suggestion and somewhat a matter of personal taste). I didn't know this existed! Changed in v2.
On Wed, 29 Aug 2018 07:43:48 +0100 Afonso Bordado <afonsobordado@az8.co> wrote: > On Mon, 2018-08-27 at 18:08 +0100, Jonathan Cameron wrote: > > On Sat, 25 Aug 2018 22:19:07 +0100 > > Afonso Bordado <afonsobordado@az8.co> wrote: > > > > > FXAS21002C is a 3 axis gyroscope with integrated temperature sensor > > > > > > Signed-off-by: Afonso Bordado <afonsobordado@az8.co> > > > > Hi, > > > > Driver is pretty clean so only a few minor comments inline. > > If we were late in a cycle I'd probably just have taken it and fixed > > up > > but as we have lots of time and I'm inherently lazy I'll let you do a > > v2 :) > > > > Good job, thanks! > > > > Jonathan > > Great! > > > > > + > > > +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 > > > > /* ... */ > > > > Please run checkpatch as IIRC it complains about this. > > I've replaced all instances of C99 comments with ANSI comments. > However, has Joe Perches mentioned. Checkpatch did not warn me about > this. > Yup, thanks to Joe for clarifying this I had missed the change. > > > > + > > > +static int fxas21002c_remove(struct i2c_client *client) > > > +{ > > > + struct iio_dev *indio_dev = i2c_get_clientdata(client); > > > + struct fxas21002c_data *data = iio_priv(indio_dev); > > > + > > > + iio_device_unregister(indio_dev); > > > + > > > + fxas21002c_set_operating_mode(data, FXAS21002C_OM_STANDBY); > > > > You could have used the devm_add_action to allow the managed cleanup > > to handle > > this and hence gotten rid of the remove function. > > > > (minor suggestion and somewhat a matter of personal taste). > > I didn't know this existed! Changed in v2. Nor me until someone used it in a driver a few months back ;) One of the advantages of doing a lot of review is that you get to see any new stuff other people use. Jonathan
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..7626b2f88d72 --- /dev/null +++ b/drivers/iio/gyro/fxas21002c.c @@ -0,0 +1,363 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * FXAS21002C - Digital Angular Rate Gyroscope driver + * + * Copyright (c) 2018, Afonso Bordado <afonsobordado@az8.co> + * + * 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) + +enum fxas21002c_id { + 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), + }, + 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 = 0; + + switch (om) { + case FXAS21002C_OM_STANDBY: + 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 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; + int raw; + __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); + break; + case IIO_TEMP: + ret = regmap_read(data->regmap, chan->address, &raw); + if (ret) + return ret; + + *val = raw * 1000; // Convert to millicelsius + break; + default: + return -EINVAL; + } + + return IIO_VAL_INT; +} + +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: + if (chan->type != IIO_ANGL_VEL) + return -EINVAL; + + *val = 0; + *val2 = FXAS21002C_DEFAULT_SENSITIVITY; + + return IIO_VAL_INT_PLUS_MICRO; + 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 = iio_device_register(indio_dev); + if (ret < 0) { + dev_err(&client->dev, "Failed to register iio device\n"); + fxas21002c_set_operating_mode(data, FXAS21002C_OM_STANDBY); + return ret; + } + + return 0; +} + +static int fxas21002c_remove(struct i2c_client *client) +{ + struct iio_dev *indio_dev = i2c_get_clientdata(client); + struct fxas21002c_data *data = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + + fxas21002c_set_operating_mode(data, FXAS21002C_OM_STANDBY); + + return 0; +} + +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, + .remove = fxas21002c_remove, + .id_table = fxas21002c_id, +}; + +module_i2c_driver(fxas21002c_driver); + +MODULE_AUTHOR("Afonso Bordado <afonsobordado@az8.co>"); +MODULE_DESCRIPTION("FXAS21002C Digital Angular Rate Gyroscope driver"); +MODULE_LICENSE("GPL v2");
FXAS21002C is a 3 axis gyroscope with integrated temperature sensor Signed-off-by: Afonso Bordado <afonsobordado@az8.co> --- drivers/iio/gyro/Kconfig | 11 ++ drivers/iio/gyro/Makefile | 1 + drivers/iio/gyro/fxas21002c.c | 363 ++++++++++++++++++++++++++++++++++ 3 files changed, 375 insertions(+) create mode 100644 drivers/iio/gyro/fxas21002c.c