drivers/iio/gyro/adis16260.c - kernel/msm-4.9 - Gitiles

 /*
  * ADIS16260/ADIS16265 Programmable Digital Gyroscope Sensor Driver
  *
  * Copyright 2010 Analog Devices Inc.
  *
  * Licensed under the GPL-2 or later.
  */

 #include <linux/interrupt.h>
 #include <linux/mutex.h>
 #include <linux/device.h>
 #include <linux/kernel.h>
 #include <linux/spi/spi.h>
 #include <linux/sysfs.h>
 #include <linux/module.h>

 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
 #include <linux/iio/buffer.h>
 #include <linux/iio/imu/adis.h>

 #define ADIS16260_STARTUP_DELAY	220 /* ms */

 #define ADIS16260_FLASH_CNT  0x00 /* Flash memory write count */
 #define ADIS16260_SUPPLY_OUT 0x02 /* Power supply measurement */
 #define ADIS16260_GYRO_OUT   0x04 /* X-axis gyroscope output */
 #define ADIS16260_AUX_ADC    0x0A /* analog input channel measurement */
 #define ADIS16260_TEMP_OUT   0x0C /* internal temperature measurement */
 #define ADIS16260_ANGL_OUT   0x0E /* angle displacement */
 #define ADIS16260_GYRO_OFF   0x14 /* Calibration, offset/bias adjustment */
 #define ADIS16260_GYRO_SCALE 0x16 /* Calibration, scale adjustment */
 #define ADIS16260_ALM_MAG1   0x20 /* Alarm 1 magnitude/polarity setting */
 #define ADIS16260_ALM_MAG2   0x22 /* Alarm 2 magnitude/polarity setting */
 #define ADIS16260_ALM_SMPL1  0x24 /* Alarm 1 dynamic rate of change setting */
 #define ADIS16260_ALM_SMPL2  0x26 /* Alarm 2 dynamic rate of change setting */
 #define ADIS16260_ALM_CTRL   0x28 /* Alarm control */
 #define ADIS16260_AUX_DAC    0x30 /* Auxiliary DAC data */
 #define ADIS16260_GPIO_CTRL  0x32 /* Control, digital I/O line */
 #define ADIS16260_MSC_CTRL   0x34 /* Control, data ready, self-test settings */
 #define ADIS16260_SMPL_PRD   0x36 /* Control, internal sample rate */
 #define ADIS16260_SENS_AVG   0x38 /* Control, dynamic range, filtering */
 #define ADIS16260_SLP_CNT    0x3A /* Control, sleep mode initiation */
 #define ADIS16260_DIAG_STAT  0x3C /* Diagnostic, error flags */
 #define ADIS16260_GLOB_CMD   0x3E /* Control, global commands */
 #define ADIS16260_LOT_ID1    0x52 /* Lot Identification Code 1 */
 #define ADIS16260_LOT_ID2    0x54 /* Lot Identification Code 2 */
 #define ADIS16260_PROD_ID    0x56 /* Product identifier;
 				   * convert to decimal = 16,265/16,260 */
 #define ADIS16260_SERIAL_NUM 0x58 /* Serial number */

 #define ADIS16260_ERROR_ACTIVE			(1<<14)
 #define ADIS16260_NEW_DATA			(1<<15)

 /* MSC_CTRL */
 #define ADIS16260_MSC_CTRL_MEM_TEST		(1<<11)
 /* Internal self-test enable */
 #define ADIS16260_MSC_CTRL_INT_SELF_TEST	(1<<10)
 #define ADIS16260_MSC_CTRL_NEG_SELF_TEST	(1<<9)
 #define ADIS16260_MSC_CTRL_POS_SELF_TEST	(1<<8)
 #define ADIS16260_MSC_CTRL_DATA_RDY_EN		(1<<2)
 #define ADIS16260_MSC_CTRL_DATA_RDY_POL_HIGH	(1<<1)
 #define ADIS16260_MSC_CTRL_DATA_RDY_DIO2	(1<<0)

 /* SMPL_PRD */
 /* Time base (tB): 0 = 1.953 ms, 1 = 60.54 ms */
 #define ADIS16260_SMPL_PRD_TIME_BASE	(1<<7)
 #define ADIS16260_SMPL_PRD_DIV_MASK	0x7F

 /* SLP_CNT */
 #define ADIS16260_SLP_CNT_POWER_OFF     0x80

 /* DIAG_STAT */
 #define ADIS16260_DIAG_STAT_ALARM2	(1<<9)
 #define ADIS16260_DIAG_STAT_ALARM1	(1<<8)
 #define ADIS16260_DIAG_STAT_FLASH_CHK_BIT	6
 #define ADIS16260_DIAG_STAT_SELF_TEST_BIT	5
 #define ADIS16260_DIAG_STAT_OVERFLOW_BIT	4
 #define ADIS16260_DIAG_STAT_SPI_FAIL_BIT	3
 #define ADIS16260_DIAG_STAT_FLASH_UPT_BIT	2
 #define ADIS16260_DIAG_STAT_POWER_HIGH_BIT	1
 #define ADIS16260_DIAG_STAT_POWER_LOW_BIT	0

 /* GLOB_CMD */
 #define ADIS16260_GLOB_CMD_SW_RESET	(1<<7)
 #define ADIS16260_GLOB_CMD_FLASH_UPD	(1<<3)
 #define ADIS16260_GLOB_CMD_DAC_LATCH	(1<<2)
 #define ADIS16260_GLOB_CMD_FAC_CALIB	(1<<1)
 #define ADIS16260_GLOB_CMD_AUTO_NULL	(1<<0)

 #define ADIS16260_SPI_SLOW	(u32)(300 * 1000)
 #define ADIS16260_SPI_BURST	(u32)(1000 * 1000)
 #define ADIS16260_SPI_FAST	(u32)(2000 * 1000)

 /* At the moment triggers are only used for ring buffer
  * filling. This may change!
  */

 #define ADIS16260_SCAN_GYRO	0
 #define ADIS16260_SCAN_SUPPLY	1
 #define ADIS16260_SCAN_AUX_ADC	2
 #define ADIS16260_SCAN_TEMP	3
 #define ADIS16260_SCAN_ANGL	4

 static ssize_t adis16260_read_frequency(struct device *dev,
 		struct device_attribute *attr,
 		char *buf)
 {
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct adis *adis = iio_priv(indio_dev);
 	int ret, len = 0;
 	u16 t;
 	int sps;
 	ret = adis_read_reg_16(adis, ADIS16260_SMPL_PRD, &t);
 	if (ret)
 		return ret;

 	if (spi_get_device_id(adis->spi)->driver_data) /* If an adis16251 */
 		sps = (t & ADIS16260_SMPL_PRD_TIME_BASE) ? 8 : 256;
 	else
 		sps = (t & ADIS16260_SMPL_PRD_TIME_BASE) ? 66 : 2048;
 	sps /= (t & ADIS16260_SMPL_PRD_DIV_MASK) + 1;
 	len = sprintf(buf, "%d\n", sps);
 	return len;
 }

 static ssize_t adis16260_write_frequency(struct device *dev,
 		struct device_attribute *attr,
 		const char *buf,
 		size_t len)
 {
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct adis *adis = iio_priv(indio_dev);
 	unsigned int val;
 	int ret;
 	u8 t;

 	ret = kstrtouint(buf, 10, &val);
 	if (ret)
 		return ret;

 	mutex_lock(&indio_dev->mlock);
 	if (spi_get_device_id(adis->spi)->driver_data)
 		t = 256 / val;
 	else
 		t = 2048 / val;

 	if (t > ADIS16260_SMPL_PRD_DIV_MASK)
 		t = ADIS16260_SMPL_PRD_DIV_MASK;
 	else if (t > 0)
 		t--;

 	if (t >= 0x0A)
 		adis->spi->max_speed_hz = ADIS16260_SPI_SLOW;
 	else
 		adis->spi->max_speed_hz = ADIS16260_SPI_FAST;
 	ret = adis_write_reg_8(adis, ADIS16260_SMPL_PRD, t);

 	mutex_unlock(&indio_dev->mlock);

 	return ret ? ret : len;
 }

 /* Power down the device */
 static int adis16260_stop_device(struct iio_dev *indio_dev)
 {
 	struct adis *adis = iio_priv(indio_dev);
 	int ret;
 	u16 val = ADIS16260_SLP_CNT_POWER_OFF;

 	ret = adis_write_reg_16(adis, ADIS16260_SLP_CNT, val);
 	if (ret)
 		dev_err(&indio_dev->dev, "problem with turning device off: SLP_CNT");

 	return ret;
 }

 static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
 		adis16260_read_frequency,
 		adis16260_write_frequency);

 static const struct iio_chan_spec adis16260_channels[] = {
 	ADIS_GYRO_CHAN(X, ADIS16260_GYRO_OUT, ADIS16260_SCAN_GYRO,
 		BIT(IIO_CHAN_INFO_CALIBBIAS) |
 		BIT(IIO_CHAN_INFO_CALIBSCALE), 14),
 	ADIS_INCLI_CHAN(X, ADIS16260_ANGL_OUT, ADIS16260_SCAN_ANGL, 0, 14),
 	ADIS_TEMP_CHAN(ADIS16260_TEMP_OUT, ADIS16260_SCAN_TEMP, 12),
 	ADIS_SUPPLY_CHAN(ADIS16260_SUPPLY_OUT, ADIS16260_SCAN_SUPPLY, 12),
 	ADIS_AUX_ADC_CHAN(ADIS16260_AUX_ADC, ADIS16260_SCAN_AUX_ADC, 12),
 	IIO_CHAN_SOFT_TIMESTAMP(5),
 };

 static const u8 adis16260_addresses[][2] = {
 	[ADIS16260_SCAN_GYRO] = { ADIS16260_GYRO_OFF, ADIS16260_GYRO_SCALE },
 };

 static int adis16260_read_raw(struct iio_dev *indio_dev,
 			      struct iio_chan_spec const *chan,
 			      int *val, int *val2,
 			      long mask)
 {
 	struct adis *adis = iio_priv(indio_dev);
 	int ret;
 	u8 addr;
 	s16 val16;

 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
 		return adis_single_conversion(indio_dev, chan,
 				ADIS16260_ERROR_ACTIVE, val);
 	case IIO_CHAN_INFO_SCALE:
 		switch (chan->type) {
 		case IIO_ANGL_VEL:
 			*val = 0;
 			if (spi_get_device_id(adis->spi)->driver_data) {
 				/* 0.01832 degree / sec */
 				*val2 = IIO_DEGREE_TO_RAD(18320);
 			} else {
 				/* 0.07326 degree / sec */
 				*val2 = IIO_DEGREE_TO_RAD(73260);
 			}
 			return IIO_VAL_INT_PLUS_MICRO;
 		case IIO_INCLI:
 			*val = 0;
 			*val2 = IIO_DEGREE_TO_RAD(36630);
 			return IIO_VAL_INT_PLUS_MICRO;
 		case IIO_VOLTAGE:
 			if (chan->channel == 0) {
 				*val = 1;
 				*val2 = 831500; /* 1.8315 mV */
 			} else {
 				*val = 0;
 				*val2 = 610500; /* 610.5 uV */
 			}
 			return IIO_VAL_INT_PLUS_MICRO;
 		case IIO_TEMP:
 			*val = 145;
 			*val2 = 300000; /* 0.1453 C */
 			return IIO_VAL_INT_PLUS_MICRO;
 		default:
 			return -EINVAL;
 		}
 		break;
 	case IIO_CHAN_INFO_OFFSET:
 		*val = 250000 / 1453; /* 25 C = 0x00 */
 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_CALIBBIAS:
 		addr = adis16260_addresses[chan->scan_index][0];
 		ret = adis_read_reg_16(adis, addr, &val16);
 		if (ret)
 			return ret;

 		*val = sign_extend32(val16, 11);
 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_CALIBSCALE:
 		addr = adis16260_addresses[chan->scan_index][1];
 		ret = adis_read_reg_16(adis, addr, &val16);
 		if (ret)
 			return ret;

 		*val = val16;
 		return IIO_VAL_INT;
 	}
 	return -EINVAL;
 }

 static int adis16260_write_raw(struct iio_dev *indio_dev,
 			       struct iio_chan_spec const *chan,
 			       int val,
 			       int val2,
 			       long mask)
 {
 	struct adis *adis = iio_priv(indio_dev);
 	u8 addr;

 	switch (mask) {
 	case IIO_CHAN_INFO_CALIBBIAS:
 		if (val < -2048 || val >= 2048)
 			return -EINVAL;

 		addr = adis16260_addresses[chan->scan_index][0];
 		return adis_write_reg_16(adis, addr, val);
 	case IIO_CHAN_INFO_CALIBSCALE:
 		if (val < 0 || val >= 4096)
 			return -EINVAL;

 		addr = adis16260_addresses[chan->scan_index][1];
 		return adis_write_reg_16(adis, addr, val);
 	}
 	return -EINVAL;
 }

 static struct attribute *adis16260_attributes[] = {
 	&iio_dev_attr_sampling_frequency.dev_attr.attr,
 	NULL
 };

 static const struct attribute_group adis16260_attribute_group = {
 	.attrs = adis16260_attributes,
 };

 static const struct iio_info adis16260_info = {
 	.attrs = &adis16260_attribute_group,
 	.read_raw = &adis16260_read_raw,
 	.write_raw = &adis16260_write_raw,
 	.update_scan_mode = adis_update_scan_mode,
 	.driver_module = THIS_MODULE,
 };

 static const char * const adis1620_status_error_msgs[] = {
 	[ADIS16260_DIAG_STAT_FLASH_CHK_BIT] = "Flash checksum error",
 	[ADIS16260_DIAG_STAT_SELF_TEST_BIT] = "Self test error",
 	[ADIS16260_DIAG_STAT_OVERFLOW_BIT] = "Sensor overrange",
 	[ADIS16260_DIAG_STAT_SPI_FAIL_BIT] = "SPI failure",
 	[ADIS16260_DIAG_STAT_FLASH_UPT_BIT] = "Flash update failed",
 	[ADIS16260_DIAG_STAT_POWER_HIGH_BIT] = "Power supply above 5.25",
 	[ADIS16260_DIAG_STAT_POWER_LOW_BIT] = "Power supply below 4.75",
 };

 static const struct adis_data adis16260_data = {
 	.write_delay = 30,
 	.read_delay = 30,
 	.msc_ctrl_reg = ADIS16260_MSC_CTRL,
 	.glob_cmd_reg = ADIS16260_GLOB_CMD,
 	.diag_stat_reg = ADIS16260_DIAG_STAT,

 	.self_test_mask = ADIS16260_MSC_CTRL_MEM_TEST,
 	.startup_delay = ADIS16260_STARTUP_DELAY,

 	.status_error_msgs = adis1620_status_error_msgs,
 	.status_error_mask = BIT(ADIS16260_DIAG_STAT_FLASH_CHK_BIT) |
 		BIT(ADIS16260_DIAG_STAT_SELF_TEST_BIT) |
 		BIT(ADIS16260_DIAG_STAT_OVERFLOW_BIT) |
 		BIT(ADIS16260_DIAG_STAT_SPI_FAIL_BIT) |
 		BIT(ADIS16260_DIAG_STAT_FLASH_UPT_BIT) |
 		BIT(ADIS16260_DIAG_STAT_POWER_HIGH_BIT) |
 		BIT(ADIS16260_DIAG_STAT_POWER_LOW_BIT),
 };

 static int adis16260_probe(struct spi_device *spi)
 {
 	struct iio_dev *indio_dev;
 	struct adis *adis;
 	int ret;

 	/* setup the industrialio driver allocated elements */
 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adis));
 	if (!indio_dev)
 		return -ENOMEM;
 	adis = iio_priv(indio_dev);
 	/* this is only used for removal purposes */
 	spi_set_drvdata(spi, indio_dev);

 	indio_dev->name = spi_get_device_id(spi)->name;
 	indio_dev->dev.parent = &spi->dev;
 	indio_dev->info = &adis16260_info;
 	indio_dev->channels = adis16260_channels;
 	indio_dev->num_channels = ARRAY_SIZE(adis16260_channels);
 	indio_dev->modes = INDIO_DIRECT_MODE;

 	ret = adis_init(adis, indio_dev, spi, &adis16260_data);
 	if (ret)
 		return ret;

 	ret = adis_setup_buffer_and_trigger(adis, indio_dev, NULL);
 	if (ret)
 		return ret;

 	/* Get the device into a sane initial state */
 	ret = adis_initial_startup(adis);
 	if (ret)
 		goto error_cleanup_buffer_trigger;
 	ret = iio_device_register(indio_dev);
 	if (ret)
 		goto error_cleanup_buffer_trigger;

 	return 0;

 error_cleanup_buffer_trigger:
 	adis_cleanup_buffer_and_trigger(adis, indio_dev);
 	return ret;
 }

 static int adis16260_remove(struct spi_device *spi)
 {
 	struct iio_dev *indio_dev = spi_get_drvdata(spi);
 	struct adis *adis = iio_priv(indio_dev);

 	iio_device_unregister(indio_dev);
 	adis16260_stop_device(indio_dev);
 	adis_cleanup_buffer_and_trigger(adis, indio_dev);

 	return 0;
 }

 /*
  * These parts do not need to be differentiated until someone adds
  * support for the on chip filtering.
  */
 static const struct spi_device_id adis16260_id[] = {
 	{"adis16260", 0},
 	{"adis16265", 0},
 	{"adis16250", 0},
 	{"adis16255", 0},
 	{"adis16251", 1},
 	{}
 };
 MODULE_DEVICE_TABLE(spi, adis16260_id);

 static struct spi_driver adis16260_driver = {
 	.driver = {
 		.name = "adis16260",
 		.owner = THIS_MODULE,
 	},
 	.probe = adis16260_probe,
 	.remove = adis16260_remove,
 	.id_table = adis16260_id,
 };
 module_spi_driver(adis16260_driver);

 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
 MODULE_DESCRIPTION("Analog Devices ADIS16260/5 Digital Gyroscope Sensor");
 MODULE_LICENSE("GPL v2");
	/*
	* ADIS16260/ADIS16265 Programmable Digital Gyroscope Sensor Driver
	*
	* Copyright 2010 Analog Devices Inc.
	*
	* Licensed under the GPL-2 or later.
	*/

	#include <linux/interrupt.h>
	#include <linux/mutex.h>
	#include <linux/device.h>
	#include <linux/kernel.h>
	#include <linux/spi/spi.h>
	#include <linux/sysfs.h>
	#include <linux/module.h>

	#include <linux/iio/iio.h>
	#include <linux/iio/sysfs.h>
	#include <linux/iio/buffer.h>
	#include <linux/iio/imu/adis.h>

	#define ADIS16260_STARTUP_DELAY 220 /* ms */

	#define ADIS16260_FLASH_CNT 0x00 /* Flash memory write count */
	#define ADIS16260_SUPPLY_OUT 0x02 /* Power supply measurement */
	#define ADIS16260_GYRO_OUT 0x04 /* X-axis gyroscope output */
	#define ADIS16260_AUX_ADC 0x0A /* analog input channel measurement */
	#define ADIS16260_TEMP_OUT 0x0C /* internal temperature measurement */
	#define ADIS16260_ANGL_OUT 0x0E /* angle displacement */
	#define ADIS16260_GYRO_OFF 0x14 /* Calibration, offset/bias adjustment */
	#define ADIS16260_GYRO_SCALE 0x16 /* Calibration, scale adjustment */
	#define ADIS16260_ALM_MAG1 0x20 /* Alarm 1 magnitude/polarity setting */
	#define ADIS16260_ALM_MAG2 0x22 /* Alarm 2 magnitude/polarity setting */
	#define ADIS16260_ALM_SMPL1 0x24 /* Alarm 1 dynamic rate of change setting */
	#define ADIS16260_ALM_SMPL2 0x26 /* Alarm 2 dynamic rate of change setting */
	#define ADIS16260_ALM_CTRL 0x28 /* Alarm control */
	#define ADIS16260_AUX_DAC 0x30 /* Auxiliary DAC data */
	#define ADIS16260_GPIO_CTRL 0x32 /* Control, digital I/O line */
	#define ADIS16260_MSC_CTRL 0x34 /* Control, data ready, self-test settings */
	#define ADIS16260_SMPL_PRD 0x36 /* Control, internal sample rate */
	#define ADIS16260_SENS_AVG 0x38 /* Control, dynamic range, filtering */
	#define ADIS16260_SLP_CNT 0x3A /* Control, sleep mode initiation */
	#define ADIS16260_DIAG_STAT 0x3C /* Diagnostic, error flags */
	#define ADIS16260_GLOB_CMD 0x3E /* Control, global commands */
	#define ADIS16260_LOT_ID1 0x52 /* Lot Identification Code 1 */
	#define ADIS16260_LOT_ID2 0x54 /* Lot Identification Code 2 */
	#define ADIS16260_PROD_ID 0x56 /* Product identifier;
	* convert to decimal = 16,265/16,260 */
	#define ADIS16260_SERIAL_NUM 0x58 /* Serial number */

	#define ADIS16260_ERROR_ACTIVE (1<<14)
	#define ADIS16260_NEW_DATA (1<<15)

	/* MSC_CTRL */
	#define ADIS16260_MSC_CTRL_MEM_TEST (1<<11)
	/* Internal self-test enable */
	#define ADIS16260_MSC_CTRL_INT_SELF_TEST (1<<10)
	#define ADIS16260_MSC_CTRL_NEG_SELF_TEST (1<<9)
	#define ADIS16260_MSC_CTRL_POS_SELF_TEST (1<<8)
	#define ADIS16260_MSC_CTRL_DATA_RDY_EN (1<<2)
	#define ADIS16260_MSC_CTRL_DATA_RDY_POL_HIGH (1<<1)
	#define ADIS16260_MSC_CTRL_DATA_RDY_DIO2 (1<<0)

	/* SMPL_PRD */
	/* Time base (tB): 0 = 1.953 ms, 1 = 60.54 ms */
	#define ADIS16260_SMPL_PRD_TIME_BASE (1<<7)
	#define ADIS16260_SMPL_PRD_DIV_MASK 0x7F

	/* SLP_CNT */
	#define ADIS16260_SLP_CNT_POWER_OFF 0x80

	/* DIAG_STAT */
	#define ADIS16260_DIAG_STAT_ALARM2 (1<<9)
	#define ADIS16260_DIAG_STAT_ALARM1 (1<<8)
	#define ADIS16260_DIAG_STAT_FLASH_CHK_BIT 6
	#define ADIS16260_DIAG_STAT_SELF_TEST_BIT 5
	#define ADIS16260_DIAG_STAT_OVERFLOW_BIT 4
	#define ADIS16260_DIAG_STAT_SPI_FAIL_BIT 3
	#define ADIS16260_DIAG_STAT_FLASH_UPT_BIT 2
	#define ADIS16260_DIAG_STAT_POWER_HIGH_BIT 1
	#define ADIS16260_DIAG_STAT_POWER_LOW_BIT 0

	/* GLOB_CMD */
	#define ADIS16260_GLOB_CMD_SW_RESET (1<<7)
	#define ADIS16260_GLOB_CMD_FLASH_UPD (1<<3)
	#define ADIS16260_GLOB_CMD_DAC_LATCH (1<<2)
	#define ADIS16260_GLOB_CMD_FAC_CALIB (1<<1)
	#define ADIS16260_GLOB_CMD_AUTO_NULL (1<<0)

	#define ADIS16260_SPI_SLOW (u32)(300 * 1000)
	#define ADIS16260_SPI_BURST (u32)(1000 * 1000)
	#define ADIS16260_SPI_FAST (u32)(2000 * 1000)

	/* At the moment triggers are only used for ring buffer
	* filling. This may change!
	*/

	#define ADIS16260_SCAN_GYRO 0
	#define ADIS16260_SCAN_SUPPLY 1
	#define ADIS16260_SCAN_AUX_ADC 2
	#define ADIS16260_SCAN_TEMP 3
	#define ADIS16260_SCAN_ANGL 4

	static ssize_t adis16260_read_frequency(struct device *dev,
	struct device_attribute *attr,
	char *buf)
	{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct adis *adis = iio_priv(indio_dev);
	int ret, len = 0;
	u16 t;
	int sps;
	ret = adis_read_reg_16(adis, ADIS16260_SMPL_PRD, &t);
	if (ret)
	return ret;

	if (spi_get_device_id(adis->spi)->driver_data) /* If an adis16251 */
	sps = (t & ADIS16260_SMPL_PRD_TIME_BASE) ? 8 : 256;
	else
	sps = (t & ADIS16260_SMPL_PRD_TIME_BASE) ? 66 : 2048;
	sps /= (t & ADIS16260_SMPL_PRD_DIV_MASK) + 1;
	len = sprintf(buf, "%d\n", sps);
	return len;
	}

	static ssize_t adis16260_write_frequency(struct device *dev,
	struct device_attribute *attr,
	const char *buf,
	size_t len)
	{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct adis *adis = iio_priv(indio_dev);
	unsigned int val;
	int ret;
	u8 t;

	ret = kstrtouint(buf, 10, &val);
	if (ret)
	return ret;

	mutex_lock(&indio_dev->mlock);
	if (spi_get_device_id(adis->spi)->driver_data)
	t = 256 / val;
	else
	t = 2048 / val;

	if (t > ADIS16260_SMPL_PRD_DIV_MASK)
	t = ADIS16260_SMPL_PRD_DIV_MASK;
	else if (t > 0)
	t--;

	if (t >= 0x0A)
	adis->spi->max_speed_hz = ADIS16260_SPI_SLOW;
	else
	adis->spi->max_speed_hz = ADIS16260_SPI_FAST;
	ret = adis_write_reg_8(adis, ADIS16260_SMPL_PRD, t);

	mutex_unlock(&indio_dev->mlock);

	return ret ? ret : len;
	}

	/* Power down the device */
	static int adis16260_stop_device(struct iio_dev *indio_dev)
	{
	struct adis *adis = iio_priv(indio_dev);
	int ret;
	u16 val = ADIS16260_SLP_CNT_POWER_OFF;

	ret = adis_write_reg_16(adis, ADIS16260_SLP_CNT, val);
	if (ret)
	dev_err(&indio_dev->dev, "problem with turning device off: SLP_CNT");

	return ret;
	}

	static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR \| S_IRUGO,
	adis16260_read_frequency,
	adis16260_write_frequency);

	static const struct iio_chan_spec adis16260_channels[] = {
	ADIS_GYRO_CHAN(X, ADIS16260_GYRO_OUT, ADIS16260_SCAN_GYRO,
	BIT(IIO_CHAN_INFO_CALIBBIAS) \|
	BIT(IIO_CHAN_INFO_CALIBSCALE), 14),
	ADIS_INCLI_CHAN(X, ADIS16260_ANGL_OUT, ADIS16260_SCAN_ANGL, 0, 14),
	ADIS_TEMP_CHAN(ADIS16260_TEMP_OUT, ADIS16260_SCAN_TEMP, 12),
	ADIS_SUPPLY_CHAN(ADIS16260_SUPPLY_OUT, ADIS16260_SCAN_SUPPLY, 12),
	ADIS_AUX_ADC_CHAN(ADIS16260_AUX_ADC, ADIS16260_SCAN_AUX_ADC, 12),
	IIO_CHAN_SOFT_TIMESTAMP(5),
	};

	static const u8 adis16260_addresses[][2] = {
	[ADIS16260_SCAN_GYRO] = { ADIS16260_GYRO_OFF, ADIS16260_GYRO_SCALE },
	};

	static int adis16260_read_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int val, int val2,
	long mask)
	{
	struct adis *adis = iio_priv(indio_dev);
	int ret;
	u8 addr;
	s16 val16;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
	return adis_single_conversion(indio_dev, chan,
	ADIS16260_ERROR_ACTIVE, val);
	case IIO_CHAN_INFO_SCALE:
	switch (chan->type) {
	case IIO_ANGL_VEL:
	*val = 0;
	if (spi_get_device_id(adis->spi)->driver_data) {
	/* 0.01832 degree / sec */
	*val2 = IIO_DEGREE_TO_RAD(18320);
	} else {
	/* 0.07326 degree / sec */
	*val2 = IIO_DEGREE_TO_RAD(73260);
	}
	return IIO_VAL_INT_PLUS_MICRO;
	case IIO_INCLI:
	*val = 0;
	*val2 = IIO_DEGREE_TO_RAD(36630);
	return IIO_VAL_INT_PLUS_MICRO;
	case IIO_VOLTAGE:
	if (chan->channel == 0) {
	*val = 1;
	val2 = 831500; / 1.8315 mV */
	} else {
	*val = 0;
	val2 = 610500; / 610.5 uV */
	}
	return IIO_VAL_INT_PLUS_MICRO;
	case IIO_TEMP:
	*val = 145;
	val2 = 300000; / 0.1453 C */
	return IIO_VAL_INT_PLUS_MICRO;
	default:
	return -EINVAL;
	}
	break;
	case IIO_CHAN_INFO_OFFSET:
	val = 250000 / 1453; / 25 C = 0x00 */
	return IIO_VAL_INT;
	case IIO_CHAN_INFO_CALIBBIAS:
	addr = adis16260_addresses[chan->scan_index][0];
	ret = adis_read_reg_16(adis, addr, &val16);
	if (ret)
	return ret;

	*val = sign_extend32(val16, 11);
	return IIO_VAL_INT;
	case IIO_CHAN_INFO_CALIBSCALE:
	addr = adis16260_addresses[chan->scan_index][1];
	ret = adis_read_reg_16(adis, addr, &val16);
	if (ret)
	return ret;

	*val = val16;
	return IIO_VAL_INT;
	}
	return -EINVAL;
	}

	static int adis16260_write_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int val,
	int val2,
	long mask)
	{
	struct adis *adis = iio_priv(indio_dev);
	u8 addr;

	switch (mask) {
	case IIO_CHAN_INFO_CALIBBIAS:
	if (val < -2048 \|\| val >= 2048)
	return -EINVAL;

	addr = adis16260_addresses[chan->scan_index][0];
	return adis_write_reg_16(adis, addr, val);
	case IIO_CHAN_INFO_CALIBSCALE:
	if (val < 0 \|\| val >= 4096)
	return -EINVAL;

	addr = adis16260_addresses[chan->scan_index][1];
	return adis_write_reg_16(adis, addr, val);
	}
	return -EINVAL;
	}

	static struct attribute *adis16260_attributes[] = {
	&iio_dev_attr_sampling_frequency.dev_attr.attr,
	NULL
	};

	static const struct attribute_group adis16260_attribute_group = {
	.attrs = adis16260_attributes,
	};

	static const struct iio_info adis16260_info = {
	.attrs = &adis16260_attribute_group,
	.read_raw = &adis16260_read_raw,
	.write_raw = &adis16260_write_raw,
	.update_scan_mode = adis_update_scan_mode,
	.driver_module = THIS_MODULE,
	};

	static const char * const adis1620_status_error_msgs[] = {
	[ADIS16260_DIAG_STAT_FLASH_CHK_BIT] = "Flash checksum error",
	[ADIS16260_DIAG_STAT_SELF_TEST_BIT] = "Self test error",
	[ADIS16260_DIAG_STAT_OVERFLOW_BIT] = "Sensor overrange",
	[ADIS16260_DIAG_STAT_SPI_FAIL_BIT] = "SPI failure",
	[ADIS16260_DIAG_STAT_FLASH_UPT_BIT] = "Flash update failed",
	[ADIS16260_DIAG_STAT_POWER_HIGH_BIT] = "Power supply above 5.25",
	[ADIS16260_DIAG_STAT_POWER_LOW_BIT] = "Power supply below 4.75",
	};

	static const struct adis_data adis16260_data = {
	.write_delay = 30,
	.read_delay = 30,
	.msc_ctrl_reg = ADIS16260_MSC_CTRL,
	.glob_cmd_reg = ADIS16260_GLOB_CMD,
	.diag_stat_reg = ADIS16260_DIAG_STAT,

	.self_test_mask = ADIS16260_MSC_CTRL_MEM_TEST,
	.startup_delay = ADIS16260_STARTUP_DELAY,

	.status_error_msgs = adis1620_status_error_msgs,
	.status_error_mask = BIT(ADIS16260_DIAG_STAT_FLASH_CHK_BIT) \|
	BIT(ADIS16260_DIAG_STAT_SELF_TEST_BIT) \|
	BIT(ADIS16260_DIAG_STAT_OVERFLOW_BIT) \|
	BIT(ADIS16260_DIAG_STAT_SPI_FAIL_BIT) \|
	BIT(ADIS16260_DIAG_STAT_FLASH_UPT_BIT) \|
	BIT(ADIS16260_DIAG_STAT_POWER_HIGH_BIT) \|
	BIT(ADIS16260_DIAG_STAT_POWER_LOW_BIT),
	};

	static int adis16260_probe(struct spi_device *spi)
	{
	struct iio_dev *indio_dev;
	struct adis *adis;
	int ret;

	/* setup the industrialio driver allocated elements */
	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adis));
	if (!indio_dev)
	return -ENOMEM;
	adis = iio_priv(indio_dev);
	/* this is only used for removal purposes */
	spi_set_drvdata(spi, indio_dev);

	indio_dev->name = spi_get_device_id(spi)->name;
	indio_dev->dev.parent = &spi->dev;
	indio_dev->info = &adis16260_info;
	indio_dev->channels = adis16260_channels;
	indio_dev->num_channels = ARRAY_SIZE(adis16260_channels);
	indio_dev->modes = INDIO_DIRECT_MODE;

	ret = adis_init(adis, indio_dev, spi, &adis16260_data);
	if (ret)
	return ret;

	ret = adis_setup_buffer_and_trigger(adis, indio_dev, NULL);
	if (ret)
	return ret;

	/* Get the device into a sane initial state */
	ret = adis_initial_startup(adis);
	if (ret)
	goto error_cleanup_buffer_trigger;
	ret = iio_device_register(indio_dev);
	if (ret)
	goto error_cleanup_buffer_trigger;

	return 0;

	error_cleanup_buffer_trigger:
	adis_cleanup_buffer_and_trigger(adis, indio_dev);
	return ret;
	}

	static int adis16260_remove(struct spi_device *spi)
	{
	struct iio_dev *indio_dev = spi_get_drvdata(spi);
	struct adis *adis = iio_priv(indio_dev);

	iio_device_unregister(indio_dev);
	adis16260_stop_device(indio_dev);
	adis_cleanup_buffer_and_trigger(adis, indio_dev);

	return 0;
	}

	/*
	* These parts do not need to be differentiated until someone adds
	* support for the on chip filtering.
	*/
	static const struct spi_device_id adis16260_id[] = {
	{"adis16260", 0},
	{"adis16265", 0},
	{"adis16250", 0},
	{"adis16255", 0},
	{"adis16251", 1},
	{}
	};
	MODULE_DEVICE_TABLE(spi, adis16260_id);

	static struct spi_driver adis16260_driver = {
	.driver = {
	.name = "adis16260",
	.owner = THIS_MODULE,
	},
	.probe = adis16260_probe,
	.remove = adis16260_remove,
	.id_table = adis16260_id,
	};
	module_spi_driver(adis16260_driver);

	MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
	MODULE_DESCRIPTION("Analog Devices ADIS16260/5 Digital Gyroscope Sensor");
	MODULE_LICENSE("GPL v2");