diff options
Diffstat (limited to 'drivers/iio/gyro/adis16130.c')
| -rw-r--r-- | drivers/iio/gyro/adis16130.c | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/drivers/iio/gyro/adis16130.c b/drivers/iio/gyro/adis16130.c new file mode 100644 index 000000000000..129acdf801a4 --- /dev/null +++ b/drivers/iio/gyro/adis16130.c @@ -0,0 +1,207 @@ +/* + * ADIS16130 Digital Output, High Precision Angular Rate Sensor driver + * + * Copyright 2010 Analog Devices Inc. + * + * Licensed under the GPL-2 or later. + */ + +#include <linux/mutex.h> +#include <linux/kernel.h> +#include <linux/spi/spi.h> +#include <linux/module.h> + +#include <linux/iio/iio.h> + +#define ADIS16130_CON 0x0 +#define ADIS16130_CON_RD (1 << 6) +#define ADIS16130_IOP 0x1 + +/* 1 = data-ready signal low when unread data on all channels; */ +#define ADIS16130_IOP_ALL_RDY (1 << 3) +#define ADIS16130_IOP_SYNC (1 << 0) /* 1 = synchronization enabled */ +#define ADIS16130_RATEDATA 0x8 /* Gyroscope output, rate of rotation */ +#define ADIS16130_TEMPDATA 0xA /* Temperature output */ +#define ADIS16130_RATECS 0x28 /* Gyroscope channel setup */ +#define ADIS16130_RATECS_EN (1 << 3) /* 1 = channel enable; */ +#define ADIS16130_TEMPCS 0x2A /* Temperature channel setup */ +#define ADIS16130_TEMPCS_EN (1 << 3) +#define ADIS16130_RATECONV 0x30 +#define ADIS16130_TEMPCONV 0x32 +#define ADIS16130_MODE 0x38 +#define ADIS16130_MODE_24BIT (1 << 1) /* 1 = 24-bit resolution; */ + +/** + * struct adis16130_state - device instance specific data + * @us: actual spi_device to write data + * @buf_lock: mutex to protect tx and rx + * @buf: unified tx/rx buffer + **/ +struct adis16130_state { + struct spi_device *us; + struct mutex buf_lock; + u8 buf[4] ____cacheline_aligned; +}; + +static int adis16130_spi_read(struct iio_dev *indio_dev, u8 reg_addr, u32 *val) +{ + int ret; + struct adis16130_state *st = iio_priv(indio_dev); + struct spi_message msg; + struct spi_transfer xfer = { + .tx_buf = st->buf, + .rx_buf = st->buf, + .len = 4, + }; + + mutex_lock(&st->buf_lock); + + st->buf[0] = ADIS16130_CON_RD | reg_addr; + st->buf[1] = st->buf[2] = st->buf[3] = 0; + + spi_message_init(&msg); + spi_message_add_tail(&xfer, &msg); + ret = spi_sync(st->us, &msg); + + if (ret == 0) + *val = (st->buf[1] << 16) | (st->buf[2] << 8) | st->buf[3]; + mutex_unlock(&st->buf_lock); + + return ret; +} + +static int adis16130_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, + long mask) +{ + int ret; + u32 temp; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + /* Take the iio_dev status lock */ + mutex_lock(&indio_dev->mlock); + ret = adis16130_spi_read(indio_dev, chan->address, &temp); + mutex_unlock(&indio_dev->mlock); + if (ret) + return ret; + *val = temp; + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + switch (chan->type) { + case IIO_ANGL_VEL: + /* 0 degree = 838860, 250 degree = 14260608 */ + *val = 250; + *val2 = 336440817; /* RAD_TO_DEGREE(14260608 - 8388608) */ + return IIO_VAL_FRACTIONAL; + case IIO_TEMP: + /* 0C = 8036283, 105C = 9516048 */ + *val = 105000; + *val2 = 9516048 - 8036283; + return IIO_VAL_FRACTIONAL; + default: + return -EINVAL; + } + break; + case IIO_CHAN_INFO_OFFSET: + switch (chan->type) { + case IIO_ANGL_VEL: + *val = -8388608; + return IIO_VAL_INT; + case IIO_TEMP: + *val = -8036283; + return IIO_VAL_INT; + default: + return -EINVAL; + } + break; + } + + return -EINVAL; +} + +static const struct iio_chan_spec adis16130_channels[] = { + { + .type = IIO_ANGL_VEL, + .modified = 1, + .channel2 = IIO_MOD_Z, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_OFFSET), + .address = ADIS16130_RATEDATA, + }, { + .type = IIO_TEMP, + .indexed = 1, + .channel = 0, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_OFFSET), + .address = ADIS16130_TEMPDATA, + } +}; + +static const struct iio_info adis16130_info = { + .read_raw = &adis16130_read_raw, + .driver_module = THIS_MODULE, +}; + +static int adis16130_probe(struct spi_device *spi) +{ + int ret; + struct adis16130_state *st; + struct iio_dev *indio_dev; + + /* setup the industrialio driver allocated elements */ + indio_dev = iio_device_alloc(sizeof(*st)); + if (indio_dev == NULL) { + ret = -ENOMEM; + goto error_ret; + } + st = iio_priv(indio_dev); + /* this is only used for removal purposes */ + spi_set_drvdata(spi, indio_dev); + st->us = spi; + mutex_init(&st->buf_lock); + indio_dev->name = spi->dev.driver->name; + indio_dev->channels = adis16130_channels; + indio_dev->num_channels = ARRAY_SIZE(adis16130_channels); + indio_dev->dev.parent = &spi->dev; + indio_dev->info = &adis16130_info; + indio_dev->modes = INDIO_DIRECT_MODE; + + ret = iio_device_register(indio_dev); + if (ret) + goto error_free_dev; + + return 0; + +error_free_dev: + iio_device_free(indio_dev); + +error_ret: + return ret; +} + +static int adis16130_remove(struct spi_device *spi) +{ + iio_device_unregister(spi_get_drvdata(spi)); + iio_device_free(spi_get_drvdata(spi)); + + return 0; +} + +static struct spi_driver adis16130_driver = { + .driver = { + .name = "adis16130", + .owner = THIS_MODULE, + }, + .probe = adis16130_probe, + .remove = adis16130_remove, +}; +module_spi_driver(adis16130_driver); + +MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>"); +MODULE_DESCRIPTION("Analog Devices ADIS16130 High Precision Angular Rate"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("spi:adis16130"); |