linux/drivers/iio/gyro/adis16130.c

179 lines
4.6 KiB
C
Raw Normal View History

/*
* 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_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;
ret = spi_sync_transfer(st->us, &xfer, 1);
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;
}
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;
}
}
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)
{
struct adis16130_state *st;
struct iio_dev *indio_dev;
/* setup the industrialio driver allocated elements */
indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
if (!indio_dev)
return -ENOMEM;
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;
return devm_iio_device_register(&spi->dev, indio_dev);
}
static struct spi_driver adis16130_driver = {
.driver = {
.name = "adis16130",
},
.probe = adis16130_probe,
};
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");