- 根目录:
- drivers
- iio
- gyro
- adxrs450.c
/*
* ADXRS450/ADXRS453 Digital Output Gyroscope Driver
*
* Copyright 2011 Analog Devices Inc.
*
* Licensed under the GPL-2.
*/
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/delay.h>
#include <linux/mutex.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/spi/spi.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#define ADXRS450_STARTUP_DELAY 50 /* ms */
/* The MSB for the spi commands */
#define ADXRS450_SENSOR_DATA (0x20 << 24)
#define ADXRS450_WRITE_DATA (0x40 << 24)
#define ADXRS450_READ_DATA (0x80 << 24)
#define ADXRS450_RATE1 0x00 /* Rate Registers */
#define ADXRS450_TEMP1 0x02 /* Temperature Registers */
#define ADXRS450_LOCST1 0x04 /* Low CST Memory Registers */
#define ADXRS450_HICST1 0x06 /* High CST Memory Registers */
#define ADXRS450_QUAD1 0x08 /* Quad Memory Registers */
#define ADXRS450_FAULT1 0x0A /* Fault Registers */
#define ADXRS450_PID1 0x0C /* Part ID Register 1 */
#define ADXRS450_SNH 0x0E /* Serial Number Registers, 4 bytes */
#define ADXRS450_SNL 0x10
#define ADXRS450_DNC1 0x12 /* Dynamic Null Correction Registers */
/* Check bits */
#define ADXRS450_P 0x01
#define ADXRS450_CHK 0x02
#define ADXRS450_CST 0x04
#define ADXRS450_PWR 0x08
#define ADXRS450_POR 0x10
#define ADXRS450_NVM 0x20
#define ADXRS450_Q 0x40
#define ADXRS450_PLL 0x80
#define ADXRS450_UV 0x100
#define ADXRS450_OV 0x200
#define ADXRS450_AMP 0x400
#define ADXRS450_FAIL 0x800
#define ADXRS450_WRERR_MASK (0x7 << 29)
#define ADXRS450_MAX_RX 4
#define ADXRS450_MAX_TX 4
#define ADXRS450_GET_ST(a) ((a >> 26) & 0x3)
enum {
ID_ADXRS450,
ID_ADXRS453,
};
/**
* struct adxrs450_state - device instance specific data
* @us: actual spi_device
* @buf_lock: mutex to protect tx and rx
* @tx: transmit buffer
* @rx: receive buffer
**/
struct adxrs450_state {
struct spi_device *us;
struct mutex buf_lock;
__be32 tx ____cacheline_aligned;
__be32 rx;
};
/**
* adxrs450_spi_read_reg_16() - read 2 bytes from a register pair
* @indio_dev: device associated with child of actual iio_dev
* @reg_address: the address of the lower of the two registers, which should be
* an even address, the second register's address is reg_address + 1.
* @val: somewhere to pass back the value read
**/
static int adxrs450_spi_read_reg_16(struct iio_dev *indio_dev,
u8 reg_address,
u16 *val)
{
struct adxrs450_state *st = iio_priv(indio_dev);
u32 tx;
int ret;
struct spi_transfer xfers[] = {
{
.tx_buf = &st->tx,
.bits_per_word = 8,
.len = sizeof(st->tx),
.cs_change = 1,
}, {
.rx_buf = &st->rx,
.bits_per_word = 8,
.len = sizeof(st->rx),
},
};
mutex_lock(&st->buf_lock);
tx = ADXRS450_READ_DATA | (reg_address << 17);
if (!(hweight32(tx) & 1))
tx |= ADXRS450_P;
st->tx = cpu_to_be32(tx);
ret = spi_sync_transfer(st->us, xfers, ARRAY_SIZE(xfers));
if (ret) {
dev_err(&st->us->dev, "problem while reading 16 bit register 0x%02x\n",
reg_address);
goto error_ret;
}
*val = (be32_to_cpu(st->rx) >> 5) & 0xFFFF;
error_ret:
mutex_unlock(&st->buf_lock);
return ret;
}
/**
* adxrs450_spi_write_reg_16() - write 2 bytes data to a register pair
* @indio_dev: device associated with child of actual actual iio_dev
* @reg_address: the address of the lower of the two registers,which should be
* an even address, the second register's address is reg_address + 1.
* @val: value to be written.
**/
static int adxrs450_spi_write_reg_16(struct iio_dev *indio_dev,
u8 reg_address,
u16 val)
{
struct adxrs450_state *st = iio_priv(indio_dev);
u32 tx;
int ret;
mutex_lock(&st->buf_lock);
tx = ADXRS450_WRITE_DATA | (reg_address << 17) | (val << 1);
if (!(hweight32(tx) & 1))
tx |= ADXRS450_P;
st->tx = cpu_to_be32(tx);
ret = spi_write(st->us, &st->tx, sizeof(st->tx));
if (ret)
dev_err(&st->us->dev, "problem while writing 16 bit register 0x%02x\n",
reg_address);
usleep_range(100, 1000); /* enforce sequential transfer delay 0.1ms */
mutex_unlock(&st->buf_lock);
return ret;
}
/**
* adxrs450_spi_sensor_data() - read 2 bytes sensor data
* @indio_dev: device associated with child of actual iio_dev
* @val: somewhere to pass back the value read
**/
static int adxrs450_spi_sensor_data(struct iio_dev *indio_dev, s16 *val)
{
struct adxrs450_state *st = iio_priv(indio_dev);
int ret;
struct spi_transfer xfers[] = {
{
.tx_buf = &st->tx,
.bits_per_word = 8,
.len = sizeof(st->tx),
.cs_change = 1,
}, {
.rx_buf = &st->rx,
.bits_per_word = 8,
.len = sizeof(st->rx),
},
};
mutex_lock(&st->buf_lock);
st->tx = cpu_to_be32(ADXRS450_SENSOR_DATA);
ret = spi_sync_transfer(st->us, xfers, ARRAY_SIZE(xfers));
if (ret) {
dev_err(&st->us->dev, "Problem while reading sensor data\n");
goto error_ret;
}
*val = (be32_to_cpu(st->rx) >> 10) & 0xFFFF;
error_ret:
mutex_unlock(&st->buf_lock);
return ret;
}
/**
* adxrs450_spi_initial() - use for initializing procedure.
* @st: device instance specific data
* @val: somewhere to pass back the value read
* @chk: Whether to perform fault check
**/
static int adxrs450_spi_initial(struct adxrs450_state *st,
u32 *val, char chk)
{
int ret;
u32 tx;
struct spi_transfer xfers = {
.tx_buf = &st->tx,
.rx_buf = &st->rx,
.bits_per_word = 8,
.len = sizeof(st->tx),
};
mutex_lock(&st->buf_lock);
tx = ADXRS450_SENSOR_DATA;
if (chk)
tx |= (ADXRS450_CHK | ADXRS450_P);
st->tx = cpu_to_be32(tx);
ret = spi_sync_transfer(st->us, &xfers, 1);
if (ret) {
dev_err(&st->us->dev, "Problem while reading initializing data\n");
goto error_ret;
}
*val = be32_to_cpu(st->rx);
error_ret:
mutex_unlock(&st->buf_lock);
return ret;
}
/* Recommended Startup Sequence by spec */
static int adxrs450_initial_setup(struct iio_dev *indio_dev)
{
u32 t;
u16 data;
int ret;
struct adxrs450_state *st = iio_priv(indio_dev);
msleep(ADXRS450_STARTUP_DELAY*2);
ret = adxrs450_spi_initial(st, &t, 1);
if (ret)
return ret;
if (t != 0x01)
dev_warn(&st->us->dev, "The initial power on response is not correct! Restart without reset?\n");
msleep(ADXRS450_STARTUP_DELAY);
ret = adxrs450_spi_initial(st, &t, 0);
if (ret)
return ret;
msleep(ADXRS450_STARTUP_DELAY);
ret = adxrs450_spi_initial(st, &t, 0);
if (ret)
return ret;
if (((t & 0xff) | 0x01) != 0xff || ADXRS450_GET_ST(t) != 2) {
dev_err(&st->us->dev, "The second response is not correct!\n");
return -EIO;
}
ret = adxrs450_spi_initial(st, &t, 0);
if (ret)
return ret;
if (((t & 0xff) | 0x01) != 0xff || ADXRS450_GET_ST(t) != 2) {
dev_err(&st->us->dev, "The third response is not correct!\n");
return -EIO;
}
ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_FAULT1, &data);
if (ret)
return ret;
if (data & 0x0fff) {
dev_err(&st->us->dev, "The device is not in normal status!\n");
return -EINVAL;
}
return 0;
}
static int adxrs450_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val,
int val2,
long mask)
{
int ret;
switch (mask) {
case IIO_CHAN_INFO_CALIBBIAS:
if (val < -0x400 || val >= 0x400)
return -EINVAL;
ret = adxrs450_spi_write_reg_16(indio_dev,
ADXRS450_DNC1, val);
break;
default:
ret = -EINVAL;
break;
}
return ret;
}
static int adxrs450_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val,
int *val2,
long mask)
{
int ret;
s16 t;
switch (mask) {
case IIO_CHAN_INFO_RAW:
switch (chan->type) {
case IIO_ANGL_VEL:
ret = adxrs450_spi_sensor_data(indio_dev, &t);
if (ret)
break;
*val = t;
ret = IIO_VAL_INT;
break;
case IIO_TEMP:
ret = adxrs450_spi_read_reg_16(indio_dev,
ADXRS450_TEMP1, &t);
if (ret)
break;
*val = (t >> 6) + 225;
ret = IIO_VAL_INT;
break;
default:
ret = -EINVAL;
break;
}
break;
case IIO_CHAN_INFO_SCALE:
switch (chan->type) {
case IIO_ANGL_VEL:
*val = 0;
*val2 = 218166;
return IIO_VAL_INT_PLUS_NANO;
case IIO_TEMP:
*val = 200;
*val2 = 0;
return IIO_VAL_INT;
default:
return -EINVAL;
}
case IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW:
ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_QUAD1, &t);
if (ret)
break;
*val = t;
ret = IIO_VAL_INT;
break;
case IIO_CHAN_INFO_CALIBBIAS:
ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_DNC1, &t);
if (ret)
break;
*val = sign_extend32(t, 9);
ret = IIO_VAL_INT;
break;
default:
ret = -EINVAL;
break;
}
return ret;
}
static const struct iio_chan_spec adxrs450_channels[2][2] = {
[ID_ADXRS450] = {
{
.type = IIO_ANGL_VEL,
.modified = 1,
.channel2 = IIO_MOD_Z,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_CALIBBIAS) |
BIT(IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
}, {
.type = IIO_TEMP,
.indexed = 1,
.channel = 0,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
}
},
[ID_ADXRS453] = {
{
.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_QUADRATURE_CORRECTION_RAW),
}, {
.type = IIO_TEMP,
.indexed = 1,
.channel = 0,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
}
},
};
static const struct iio_info adxrs450_info = {
.driver_module = THIS_MODULE,
.read_raw = &adxrs450_read_raw,
.write_raw = &adxrs450_write_raw,
};
static int adxrs450_probe(struct spi_device *spi)
{
int ret;
struct adxrs450_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);
st->us = spi;
mutex_init(&st->buf_lock);
/* This is only used for removal purposes */
spi_set_drvdata(spi, indio_dev);
indio_dev->dev.parent = &spi->dev;
indio_dev->info = &adxrs450_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels =
adxrs450_channels[spi_get_device_id(spi)->driver_data];
indio_dev->num_channels = ARRAY_SIZE(adxrs450_channels);
indio_dev->name = spi->dev.driver->name;
ret = devm_iio_device_register(&spi->dev, indio_dev);
if (ret)
return ret;
/* Get the device into a sane initial state */
ret = adxrs450_initial_setup(indio_dev);
if (ret)
return ret;
return 0;
}
static const struct spi_device_id adxrs450_id[] = {
{"adxrs450", ID_ADXRS450},
{"adxrs453", ID_ADXRS453},
{}
};
MODULE_DEVICE_TABLE(spi, adxrs450_id);
static struct spi_driver adxrs450_driver = {
.driver = {
.name = "adxrs450",
.owner = THIS_MODULE,
},
.probe = adxrs450_probe,
.id_table = adxrs450_id,
};
module_spi_driver(adxrs450_driver);
MODULE_AUTHOR("Cliff Cai <cliff.cai@xxxxxxxxxx>");
MODULE_DESCRIPTION("Analog Devices ADXRS450/ADXRS453 Gyroscope SPI driver");
MODULE_LICENSE("GPL v2");