drivers/iio/gyro/adis16136.c - kernel/msm-4.9 - Gitiles

 /*
  * ADIS16133/ADIS16135/ADIS16136 gyroscope driver
  *
  * Copyright 2012 Analog Devices Inc.
  *   Author: Lars-Peter Clausen <lars@metafoo.de>
  *
  * Licensed under the GPL-2.
  */

 #include <linux/interrupt.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/module.h>

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

 #include <linux/debugfs.h>

 #define ADIS16136_REG_FLASH_CNT		0x00
 #define ADIS16136_REG_TEMP_OUT		0x02
 #define ADIS16136_REG_GYRO_OUT2		0x04
 #define ADIS16136_REG_GYRO_OUT		0x06
 #define ADIS16136_REG_GYRO_OFF2		0x08
 #define ADIS16136_REG_GYRO_OFF		0x0A
 #define ADIS16136_REG_ALM_MAG1		0x10
 #define ADIS16136_REG_ALM_MAG2		0x12
 #define ADIS16136_REG_ALM_SAMPL1	0x14
 #define ADIS16136_REG_ALM_SAMPL2	0x16
 #define ADIS16136_REG_ALM_CTRL		0x18
 #define ADIS16136_REG_GPIO_CTRL		0x1A
 #define ADIS16136_REG_MSC_CTRL		0x1C
 #define ADIS16136_REG_SMPL_PRD		0x1E
 #define ADIS16136_REG_AVG_CNT		0x20
 #define ADIS16136_REG_DEC_RATE		0x22
 #define ADIS16136_REG_SLP_CTRL		0x24
 #define ADIS16136_REG_DIAG_STAT		0x26
 #define ADIS16136_REG_GLOB_CMD		0x28
 #define ADIS16136_REG_LOT1		0x32
 #define ADIS16136_REG_LOT2		0x34
 #define ADIS16136_REG_LOT3		0x36
 #define ADIS16136_REG_PROD_ID		0x38
 #define ADIS16136_REG_SERIAL_NUM	0x3A

 #define ADIS16136_DIAG_STAT_FLASH_UPDATE_FAIL	2
 #define ADIS16136_DIAG_STAT_SPI_FAIL		3
 #define ADIS16136_DIAG_STAT_SELF_TEST_FAIL	5
 #define ADIS16136_DIAG_STAT_FLASH_CHKSUM_FAIL	6

 #define ADIS16136_MSC_CTRL_MEMORY_TEST BIT(11)
 #define ADIS16136_MSC_CTRL_SELF_TEST BIT(10)

 struct adis16136_chip_info {
 	unsigned int precision;
 	unsigned int fullscale;
 };

 struct adis16136 {
 	const struct adis16136_chip_info *chip_info;

 	struct adis adis;
 };

 #ifdef CONFIG_DEBUG_FS

 static ssize_t adis16136_show_serial(struct file *file,
 		char __user *userbuf, size_t count, loff_t *ppos)
 {
 	struct adis16136 *adis16136 = file->private_data;
 	uint16_t lot1, lot2, lot3, serial;
 	char buf[20];
 	size_t len;
 	int ret;

 	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_SERIAL_NUM,
 		&serial);
 	if (ret < 0)
 		return ret;

 	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_LOT1, &lot1);
 	if (ret < 0)
 		return ret;

 	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_LOT2, &lot2);
 	if (ret < 0)
 		return ret;

 	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_LOT3, &lot3);
 	if (ret < 0)
 		return ret;

 	len = snprintf(buf, sizeof(buf), "%.4x%.4x%.4x-%.4x\n", lot1, lot2,
 		lot3, serial);

 	return simple_read_from_buffer(userbuf, count, ppos, buf, len);
 }

 static const struct file_operations adis16136_serial_fops = {
 	.open = simple_open,
 	.read = adis16136_show_serial,
 	.llseek = default_llseek,
 	.owner = THIS_MODULE,
 };

 static int adis16136_show_product_id(void *arg, u64 *val)
 {
 	struct adis16136 *adis16136 = arg;
 	u16 prod_id;
 	int ret;

 	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_PROD_ID,
 		&prod_id);
 	if (ret < 0)
 		return ret;

 	*val = prod_id;

 	return 0;
 }
 DEFINE_SIMPLE_ATTRIBUTE(adis16136_product_id_fops,
 	adis16136_show_product_id, NULL, "%llu\n");

 static int adis16136_show_flash_count(void *arg, u64 *val)
 {
 	struct adis16136 *adis16136 = arg;
 	uint16_t flash_count;
 	int ret;

 	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_FLASH_CNT,
 		&flash_count);
 	if (ret < 0)
 		return ret;

 	*val = flash_count;

 	return 0;
 }
 DEFINE_SIMPLE_ATTRIBUTE(adis16136_flash_count_fops,
 	adis16136_show_flash_count, NULL, "%lld\n");

 static int adis16136_debugfs_init(struct iio_dev *indio_dev)
 {
 	struct adis16136 *adis16136 = iio_priv(indio_dev);

 	debugfs_create_file("serial_number", 0400, indio_dev->debugfs_dentry,
 		adis16136, &adis16136_serial_fops);
 	debugfs_create_file("product_id", 0400, indio_dev->debugfs_dentry,
 		adis16136, &adis16136_product_id_fops);
 	debugfs_create_file("flash_count", 0400, indio_dev->debugfs_dentry,
 		adis16136, &adis16136_flash_count_fops);

 	return 0;
 }

 #else

 static int adis16136_debugfs_init(struct iio_dev *indio_dev)
 {
 	return 0;
 }

 #endif

 static int adis16136_set_freq(struct adis16136 *adis16136, unsigned int freq)
 {
 	unsigned int t;

 	t = 32768 / freq;
 	if (t < 0xf)
 		t = 0xf;
 	else if (t > 0xffff)
 		t = 0xffff;
 	else
 		t--;

 	return adis_write_reg_16(&adis16136->adis, ADIS16136_REG_SMPL_PRD, t);
 }

 static int adis16136_get_freq(struct adis16136 *adis16136, unsigned int *freq)
 {
 	uint16_t t;
 	int ret;

 	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_SMPL_PRD, &t);
 	if (ret < 0)
 		return ret;

 	*freq = 32768 / (t + 1);

 	return 0;
 }

 static ssize_t adis16136_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 adis16136 *adis16136 = iio_priv(indio_dev);
 	unsigned int val;
 	int ret;

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

 	if (val == 0)
 		return -EINVAL;

 	ret = adis16136_set_freq(adis16136, val);

 	return ret ? ret : len;
 }

 static ssize_t adis16136_read_frequency(struct device *dev,
 	struct device_attribute *attr, char *buf)
 {
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct adis16136 *adis16136 = iio_priv(indio_dev);
 	unsigned int freq;
 	int ret;

 	ret = adis16136_get_freq(adis16136, &freq);
 	if (ret < 0)
 		return ret;

 	return sprintf(buf, "%d\n", freq);
 }

 static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
 				  adis16136_read_frequency,
 				  adis16136_write_frequency);

 static const unsigned adis16136_3db_divisors[] = {
 	[0] = 2, /* Special case */
 	[1] = 6,
 	[2] = 12,
 	[3] = 25,
 	[4] = 50,
 	[5] = 100,
 	[6] = 200,
 	[7] = 200, /* Not a valid setting */
 };

 static int adis16136_set_filter(struct iio_dev *indio_dev, int val)
 {
 	struct adis16136 *adis16136 = iio_priv(indio_dev);
 	unsigned int freq;
 	int i, ret;

 	ret = adis16136_get_freq(adis16136, &freq);
 	if (ret < 0)
 		return ret;

 	for (i = ARRAY_SIZE(adis16136_3db_divisors) - 1; i >= 1; i--) {
 		if (freq / adis16136_3db_divisors[i] >= val)
 			break;
 	}

 	return adis_write_reg_16(&adis16136->adis, ADIS16136_REG_AVG_CNT, i);
 }

 static int adis16136_get_filter(struct iio_dev *indio_dev, int *val)
 {
 	struct adis16136 *adis16136 = iio_priv(indio_dev);
 	unsigned int freq;
 	uint16_t val16;
 	int ret;

 	mutex_lock(&indio_dev->mlock);

 	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_AVG_CNT, &val16);
 	if (ret < 0)
 		goto err_unlock;

 	ret = adis16136_get_freq(adis16136, &freq);
 	if (ret < 0)
 		goto err_unlock;

 	*val = freq / adis16136_3db_divisors[val16 & 0x07];

 err_unlock:
 	mutex_unlock(&indio_dev->mlock);

 	return ret ? ret : IIO_VAL_INT;
 }

 static int adis16136_read_raw(struct iio_dev *indio_dev,
 	const struct iio_chan_spec *chan, int *val, int *val2, long info)
 {
 	struct adis16136 *adis16136 = iio_priv(indio_dev);
 	uint32_t val32;
 	int ret;

 	switch (info) {
 	case IIO_CHAN_INFO_RAW:
 		return adis_single_conversion(indio_dev, chan, 0, val);
 	case IIO_CHAN_INFO_SCALE:
 		switch (chan->type) {
 		case IIO_ANGL_VEL:
 			*val = adis16136->chip_info->precision;
 			*val2 = (adis16136->chip_info->fullscale << 16);
 			return IIO_VAL_FRACTIONAL;
 		case IIO_TEMP:
 			*val = 10;
 			*val2 = 697000; /* 0.010697 degree Celsius */
 			return IIO_VAL_INT_PLUS_MICRO;
 		default:
 			return -EINVAL;
 		}
 	case IIO_CHAN_INFO_CALIBBIAS:
 		ret = adis_read_reg_32(&adis16136->adis,
 			ADIS16136_REG_GYRO_OFF2, &val32);
 		if (ret < 0)
 			return ret;

 		*val = sign_extend32(val32, 31);

 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
 		return adis16136_get_filter(indio_dev, val);
 	default:
 		return -EINVAL;
 	}
 }

 static int adis16136_write_raw(struct iio_dev *indio_dev,
 	const struct iio_chan_spec *chan, int val, int val2, long info)
 {
 	struct adis16136 *adis16136 = iio_priv(indio_dev);

 	switch (info) {
 	case IIO_CHAN_INFO_CALIBBIAS:
 		return adis_write_reg_32(&adis16136->adis,
 			ADIS16136_REG_GYRO_OFF2, val);
 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
 		return adis16136_set_filter(indio_dev, val);
 	default:
 		break;
 	}

 	return -EINVAL;
 }

 enum {
 	ADIS16136_SCAN_GYRO,
 	ADIS16136_SCAN_TEMP,
 };

 static const struct iio_chan_spec adis16136_channels[] = {
 	{
 		.type = IIO_ANGL_VEL,
 		.modified = 1,
 		.channel2 = IIO_MOD_X,
 		.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |
 			IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT |
 			IIO_CHAN_INFO_SCALE_SHARED_BIT |
 			IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SEPARATE_BIT,
 		.address = ADIS16136_REG_GYRO_OUT2,
 		.scan_index = ADIS16136_SCAN_GYRO,
 		.scan_type = {
 			.sign = 's',
 			.realbits = 32,
 			.storagebits = 32,
 			.endianness = IIO_BE,
 		},
 	}, {
 		.type = IIO_TEMP,
 		.indexed = 1,
 		.channel = 0,
 		.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |
 			IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
 		.address = ADIS16136_REG_TEMP_OUT,
 		.scan_index = ADIS16136_SCAN_TEMP,
 		.scan_type = {
 			.sign = 's',
 			.realbits = 16,
 			.storagebits = 16,
 			.endianness = IIO_BE,
 		},
 	},
 	IIO_CHAN_SOFT_TIMESTAMP(2),
 };

 static struct attribute *adis16136_attributes[] = {
 	&iio_dev_attr_sampling_frequency.dev_attr.attr,
 	NULL
 };

 static const struct attribute_group adis16136_attribute_group = {
 	.attrs = adis16136_attributes,
 };

 static const struct iio_info adis16136_info = {
 	.driver_module = THIS_MODULE,
 	.attrs = &adis16136_attribute_group,
 	.read_raw = &adis16136_read_raw,
 	.write_raw = &adis16136_write_raw,
 	.update_scan_mode = adis_update_scan_mode,
 	.debugfs_reg_access = adis_debugfs_reg_access,
 };

 static int adis16136_stop_device(struct iio_dev *indio_dev)
 {
 	struct adis16136 *adis16136 = iio_priv(indio_dev);
 	int ret;

 	ret = adis_write_reg_16(&adis16136->adis, ADIS16136_REG_SLP_CTRL, 0xff);
 	if (ret)
 		dev_err(&indio_dev->dev,
 			"Could not power down device: %d\n", ret);

 	return ret;
 }

 static int adis16136_initial_setup(struct iio_dev *indio_dev)
 {
 	struct adis16136 *adis16136 = iio_priv(indio_dev);
 	unsigned int device_id;
 	uint16_t prod_id;
 	int ret;

 	ret = adis_initial_startup(&adis16136->adis);
 	if (ret)
 		return ret;

 	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_PROD_ID,
 		&prod_id);
 	if (ret)
 		return ret;

 	sscanf(indio_dev->name, "adis%u\n", &device_id);

 	if (prod_id != device_id)
 		dev_warn(&indio_dev->dev, "Device ID(%u) and product ID(%u) do not match.",
 				device_id, prod_id);

 	return 0;
 }

 static const char * const adis16136_status_error_msgs[] = {
 	[ADIS16136_DIAG_STAT_FLASH_UPDATE_FAIL] = "Flash update failed",
 	[ADIS16136_DIAG_STAT_SPI_FAIL] = "SPI failure",
 	[ADIS16136_DIAG_STAT_SELF_TEST_FAIL] = "Self test error",
 	[ADIS16136_DIAG_STAT_FLASH_CHKSUM_FAIL] = "Flash checksum error",
 };

 static const struct adis_data adis16136_data = {
 	.diag_stat_reg = ADIS16136_REG_DIAG_STAT,
 	.glob_cmd_reg = ADIS16136_REG_GLOB_CMD,
 	.msc_ctrl_reg = ADIS16136_REG_MSC_CTRL,

 	.self_test_mask = ADIS16136_MSC_CTRL_SELF_TEST,
 	.startup_delay = 80,

 	.read_delay = 10,
 	.write_delay = 10,

 	.status_error_msgs = adis16136_status_error_msgs,
 	.status_error_mask = BIT(ADIS16136_DIAG_STAT_FLASH_UPDATE_FAIL) |
 		BIT(ADIS16136_DIAG_STAT_SPI_FAIL) |
 		BIT(ADIS16136_DIAG_STAT_SELF_TEST_FAIL) |
 		BIT(ADIS16136_DIAG_STAT_FLASH_CHKSUM_FAIL),
 };

 enum adis16136_id {
 	ID_ADIS16133,
 	ID_ADIS16135,
 	ID_ADIS16136,
 };

 static const struct adis16136_chip_info adis16136_chip_info[] = {
 	[ID_ADIS16133] = {
 		.precision = IIO_DEGREE_TO_RAD(1200),
 		.fullscale = 24000,
 	},
 	[ID_ADIS16135] = {
 		.precision = IIO_DEGREE_TO_RAD(300),
 		.fullscale = 24000,
 	},
 	[ID_ADIS16136] = {
 		.precision = IIO_DEGREE_TO_RAD(450),
 		.fullscale = 24623,
 	},
 };

 static int adis16136_probe(struct spi_device *spi)
 {
 	const struct spi_device_id *id = spi_get_device_id(spi);
 	struct adis16136 *adis16136;
 	struct iio_dev *indio_dev;
 	int ret;

 	indio_dev = iio_device_alloc(sizeof(*adis16136));
 	if (indio_dev == NULL)
 		return -ENOMEM;

 	spi_set_drvdata(spi, indio_dev);

 	adis16136 = iio_priv(indio_dev);

 	adis16136->chip_info = &adis16136_chip_info[id->driver_data];
 	indio_dev->dev.parent = &spi->dev;
 	indio_dev->name = spi_get_device_id(spi)->name;
 	indio_dev->channels = adis16136_channels;
 	indio_dev->num_channels = ARRAY_SIZE(adis16136_channels);
 	indio_dev->info = &adis16136_info;
 	indio_dev->modes = INDIO_DIRECT_MODE;

 	ret = adis_init(&adis16136->adis, indio_dev, spi, &adis16136_data);
 	if (ret)
 		goto error_free_dev;

 	ret = adis_setup_buffer_and_trigger(&adis16136->adis, indio_dev, NULL);
 	if (ret)
 		goto error_free_dev;

 	ret = adis16136_initial_setup(indio_dev);
 	if (ret)
 		goto error_cleanup_buffer;

 	ret = iio_device_register(indio_dev);
 	if (ret)
 		goto error_stop_device;

 	adis16136_debugfs_init(indio_dev);

 	return 0;

 error_stop_device:
 	adis16136_stop_device(indio_dev);
 error_cleanup_buffer:
 	adis_cleanup_buffer_and_trigger(&adis16136->adis, indio_dev);
 error_free_dev:
 	iio_device_free(indio_dev);
 	return ret;
 }

 static int adis16136_remove(struct spi_device *spi)
 {
 	struct iio_dev *indio_dev = spi_get_drvdata(spi);
 	struct adis16136 *adis16136 = iio_priv(indio_dev);

 	iio_device_unregister(indio_dev);
 	adis16136_stop_device(indio_dev);

 	adis_cleanup_buffer_and_trigger(&adis16136->adis, indio_dev);

 	iio_device_free(indio_dev);

 	return 0;
 }

 static const struct spi_device_id adis16136_ids[] = {
 	{ "adis16133", ID_ADIS16133 },
 	{ "adis16135", ID_ADIS16135 },
 	{ "adis16136", ID_ADIS16136 },
 	{ }
 };
 MODULE_DEVICE_TABLE(spi, adis16136_ids);

 static struct spi_driver adis16136_driver = {
 	.driver = {
 		.name = "adis16136",
 		.owner = THIS_MODULE,
 	},
 	.id_table = adis16136_ids,
 	.probe = adis16136_probe,
 	.remove = adis16136_remove,
 };
 module_spi_driver(adis16136_driver);

 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 MODULE_DESCRIPTION("Analog Devices ADIS16133/ADIS16135/ADIS16136 gyroscope driver");
 MODULE_LICENSE("GPL v2");
	/*
	* ADIS16133/ADIS16135/ADIS16136 gyroscope driver
	*
	* Copyright 2012 Analog Devices Inc.
	* Author: Lars-Peter Clausen <lars@metafoo.de>
	*
	* Licensed under the GPL-2.
	*/

	#include <linux/interrupt.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/module.h>

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

	#include <linux/debugfs.h>

	#define ADIS16136_REG_FLASH_CNT 0x00
	#define ADIS16136_REG_TEMP_OUT 0x02
	#define ADIS16136_REG_GYRO_OUT2 0x04
	#define ADIS16136_REG_GYRO_OUT 0x06
	#define ADIS16136_REG_GYRO_OFF2 0x08
	#define ADIS16136_REG_GYRO_OFF 0x0A
	#define ADIS16136_REG_ALM_MAG1 0x10
	#define ADIS16136_REG_ALM_MAG2 0x12
	#define ADIS16136_REG_ALM_SAMPL1 0x14
	#define ADIS16136_REG_ALM_SAMPL2 0x16
	#define ADIS16136_REG_ALM_CTRL 0x18
	#define ADIS16136_REG_GPIO_CTRL 0x1A
	#define ADIS16136_REG_MSC_CTRL 0x1C
	#define ADIS16136_REG_SMPL_PRD 0x1E
	#define ADIS16136_REG_AVG_CNT 0x20
	#define ADIS16136_REG_DEC_RATE 0x22
	#define ADIS16136_REG_SLP_CTRL 0x24
	#define ADIS16136_REG_DIAG_STAT 0x26
	#define ADIS16136_REG_GLOB_CMD 0x28
	#define ADIS16136_REG_LOT1 0x32
	#define ADIS16136_REG_LOT2 0x34
	#define ADIS16136_REG_LOT3 0x36
	#define ADIS16136_REG_PROD_ID 0x38
	#define ADIS16136_REG_SERIAL_NUM 0x3A

	#define ADIS16136_DIAG_STAT_FLASH_UPDATE_FAIL 2
	#define ADIS16136_DIAG_STAT_SPI_FAIL 3
	#define ADIS16136_DIAG_STAT_SELF_TEST_FAIL 5
	#define ADIS16136_DIAG_STAT_FLASH_CHKSUM_FAIL 6

	#define ADIS16136_MSC_CTRL_MEMORY_TEST BIT(11)
	#define ADIS16136_MSC_CTRL_SELF_TEST BIT(10)

	struct adis16136_chip_info {
	unsigned int precision;
	unsigned int fullscale;
	};

	struct adis16136 {
	const struct adis16136_chip_info *chip_info;

	struct adis adis;
	};

	#ifdef CONFIG_DEBUG_FS

	static ssize_t adis16136_show_serial(struct file *file,
	char __user userbuf, size_t count, loff_t ppos)
	{
	struct adis16136 *adis16136 = file->private_data;
	uint16_t lot1, lot2, lot3, serial;
	char buf[20];
	size_t len;
	int ret;

	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_SERIAL_NUM,
	&serial);
	if (ret < 0)
	return ret;

	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_LOT1, &lot1);
	if (ret < 0)
	return ret;

	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_LOT2, &lot2);
	if (ret < 0)
	return ret;

	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_LOT3, &lot3);
	if (ret < 0)
	return ret;

	len = snprintf(buf, sizeof(buf), "%.4x%.4x%.4x-%.4x\n", lot1, lot2,
	lot3, serial);

	return simple_read_from_buffer(userbuf, count, ppos, buf, len);
	}

	static const struct file_operations adis16136_serial_fops = {
	.open = simple_open,
	.read = adis16136_show_serial,
	.llseek = default_llseek,
	.owner = THIS_MODULE,
	};

	static int adis16136_show_product_id(void arg, u64 val)
	{
	struct adis16136 *adis16136 = arg;
	u16 prod_id;
	int ret;

	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_PROD_ID,
	&prod_id);
	if (ret < 0)
	return ret;

	*val = prod_id;

	return 0;
	}
	DEFINE_SIMPLE_ATTRIBUTE(adis16136_product_id_fops,
	adis16136_show_product_id, NULL, "%llu\n");

	static int adis16136_show_flash_count(void arg, u64 val)
	{
	struct adis16136 *adis16136 = arg;
	uint16_t flash_count;
	int ret;

	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_FLASH_CNT,
	&flash_count);
	if (ret < 0)
	return ret;

	*val = flash_count;

	return 0;
	}
	DEFINE_SIMPLE_ATTRIBUTE(adis16136_flash_count_fops,
	adis16136_show_flash_count, NULL, "%lld\n");

	static int adis16136_debugfs_init(struct iio_dev *indio_dev)
	{
	struct adis16136 *adis16136 = iio_priv(indio_dev);

	debugfs_create_file("serial_number", 0400, indio_dev->debugfs_dentry,
	adis16136, &adis16136_serial_fops);
	debugfs_create_file("product_id", 0400, indio_dev->debugfs_dentry,
	adis16136, &adis16136_product_id_fops);
	debugfs_create_file("flash_count", 0400, indio_dev->debugfs_dentry,
	adis16136, &adis16136_flash_count_fops);

	return 0;
	}

	#else

	static int adis16136_debugfs_init(struct iio_dev *indio_dev)
	{
	return 0;
	}

	#endif

	static int adis16136_set_freq(struct adis16136 *adis16136, unsigned int freq)
	{
	unsigned int t;

	t = 32768 / freq;
	if (t < 0xf)
	t = 0xf;
	else if (t > 0xffff)
	t = 0xffff;
	else
	t--;

	return adis_write_reg_16(&adis16136->adis, ADIS16136_REG_SMPL_PRD, t);
	}

	static int adis16136_get_freq(struct adis16136 adis16136, unsigned int freq)
	{
	uint16_t t;
	int ret;

	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_SMPL_PRD, &t);
	if (ret < 0)
	return ret;

	*freq = 32768 / (t + 1);

	return 0;
	}

	static ssize_t adis16136_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 adis16136 *adis16136 = iio_priv(indio_dev);
	unsigned int val;
	int ret;

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

	if (val == 0)
	return -EINVAL;

	ret = adis16136_set_freq(adis16136, val);

	return ret ? ret : len;
	}

	static ssize_t adis16136_read_frequency(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct adis16136 *adis16136 = iio_priv(indio_dev);
	unsigned int freq;
	int ret;

	ret = adis16136_get_freq(adis16136, &freq);
	if (ret < 0)
	return ret;

	return sprintf(buf, "%d\n", freq);
	}

	static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR \| S_IRUGO,
	adis16136_read_frequency,
	adis16136_write_frequency);

	static const unsigned adis16136_3db_divisors[] = {
	[0] = 2, /* Special case */
	[1] = 6,
	[2] = 12,
	[3] = 25,
	[4] = 50,
	[5] = 100,
	[6] = 200,
	[7] = 200, /* Not a valid setting */
	};

	static int adis16136_set_filter(struct iio_dev *indio_dev, int val)
	{
	struct adis16136 *adis16136 = iio_priv(indio_dev);
	unsigned int freq;
	int i, ret;

	ret = adis16136_get_freq(adis16136, &freq);
	if (ret < 0)
	return ret;

	for (i = ARRAY_SIZE(adis16136_3db_divisors) - 1; i >= 1; i--) {
	if (freq / adis16136_3db_divisors[i] >= val)
	break;
	}

	return adis_write_reg_16(&adis16136->adis, ADIS16136_REG_AVG_CNT, i);
	}

	static int adis16136_get_filter(struct iio_dev indio_dev, int val)
	{
	struct adis16136 *adis16136 = iio_priv(indio_dev);
	unsigned int freq;
	uint16_t val16;
	int ret;

	mutex_lock(&indio_dev->mlock);

	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_AVG_CNT, &val16);
	if (ret < 0)
	goto err_unlock;

	ret = adis16136_get_freq(adis16136, &freq);
	if (ret < 0)
	goto err_unlock;

	*val = freq / adis16136_3db_divisors[val16 & 0x07];

	err_unlock:
	mutex_unlock(&indio_dev->mlock);

	return ret ? ret : IIO_VAL_INT;
	}

	static int adis16136_read_raw(struct iio_dev *indio_dev,
	const struct iio_chan_spec chan, int val, int *val2, long info)
	{
	struct adis16136 *adis16136 = iio_priv(indio_dev);
	uint32_t val32;
	int ret;

	switch (info) {
	case IIO_CHAN_INFO_RAW:
	return adis_single_conversion(indio_dev, chan, 0, val);
	case IIO_CHAN_INFO_SCALE:
	switch (chan->type) {
	case IIO_ANGL_VEL:
	*val = adis16136->chip_info->precision;
	*val2 = (adis16136->chip_info->fullscale << 16);
	return IIO_VAL_FRACTIONAL;
	case IIO_TEMP:
	*val = 10;
	val2 = 697000; / 0.010697 degree Celsius */
	return IIO_VAL_INT_PLUS_MICRO;
	default:
	return -EINVAL;
	}
	case IIO_CHAN_INFO_CALIBBIAS:
	ret = adis_read_reg_32(&adis16136->adis,
	ADIS16136_REG_GYRO_OFF2, &val32);
	if (ret < 0)
	return ret;

	*val = sign_extend32(val32, 31);

	return IIO_VAL_INT;
	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
	return adis16136_get_filter(indio_dev, val);
	default:
	return -EINVAL;
	}
	}

	static int adis16136_write_raw(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan, int val, int val2, long info)
	{
	struct adis16136 *adis16136 = iio_priv(indio_dev);

	switch (info) {
	case IIO_CHAN_INFO_CALIBBIAS:
	return adis_write_reg_32(&adis16136->adis,
	ADIS16136_REG_GYRO_OFF2, val);
	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
	return adis16136_set_filter(indio_dev, val);
	default:
	break;
	}

	return -EINVAL;
	}

	enum {
	ADIS16136_SCAN_GYRO,
	ADIS16136_SCAN_TEMP,
	};

	static const struct iio_chan_spec adis16136_channels[] = {
	{
	.type = IIO_ANGL_VEL,
	.modified = 1,
	.channel2 = IIO_MOD_X,
	.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT \|
	IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT \|
	IIO_CHAN_INFO_SCALE_SHARED_BIT \|
	IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SEPARATE_BIT,
	.address = ADIS16136_REG_GYRO_OUT2,
	.scan_index = ADIS16136_SCAN_GYRO,
	.scan_type = {
	.sign = 's',
	.realbits = 32,
	.storagebits = 32,
	.endianness = IIO_BE,
	},
	}, {
	.type = IIO_TEMP,
	.indexed = 1,
	.channel = 0,
	.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT \|
	IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
	.address = ADIS16136_REG_TEMP_OUT,
	.scan_index = ADIS16136_SCAN_TEMP,
	.scan_type = {
	.sign = 's',
	.realbits = 16,
	.storagebits = 16,
	.endianness = IIO_BE,
	},
	},
	IIO_CHAN_SOFT_TIMESTAMP(2),
	};

	static struct attribute *adis16136_attributes[] = {
	&iio_dev_attr_sampling_frequency.dev_attr.attr,
	NULL
	};

	static const struct attribute_group adis16136_attribute_group = {
	.attrs = adis16136_attributes,
	};

	static const struct iio_info adis16136_info = {
	.driver_module = THIS_MODULE,
	.attrs = &adis16136_attribute_group,
	.read_raw = &adis16136_read_raw,
	.write_raw = &adis16136_write_raw,
	.update_scan_mode = adis_update_scan_mode,
	.debugfs_reg_access = adis_debugfs_reg_access,
	};

	static int adis16136_stop_device(struct iio_dev *indio_dev)
	{
	struct adis16136 *adis16136 = iio_priv(indio_dev);
	int ret;

	ret = adis_write_reg_16(&adis16136->adis, ADIS16136_REG_SLP_CTRL, 0xff);
	if (ret)
	dev_err(&indio_dev->dev,
	"Could not power down device: %d\n", ret);

	return ret;
	}

	static int adis16136_initial_setup(struct iio_dev *indio_dev)
	{
	struct adis16136 *adis16136 = iio_priv(indio_dev);
	unsigned int device_id;
	uint16_t prod_id;
	int ret;

	ret = adis_initial_startup(&adis16136->adis);
	if (ret)
	return ret;

	ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_PROD_ID,
	&prod_id);
	if (ret)
	return ret;

	sscanf(indio_dev->name, "adis%u\n", &device_id);

	if (prod_id != device_id)
	dev_warn(&indio_dev->dev, "Device ID(%u) and product ID(%u) do not match.",
	device_id, prod_id);

	return 0;
	}

	static const char * const adis16136_status_error_msgs[] = {
	[ADIS16136_DIAG_STAT_FLASH_UPDATE_FAIL] = "Flash update failed",
	[ADIS16136_DIAG_STAT_SPI_FAIL] = "SPI failure",
	[ADIS16136_DIAG_STAT_SELF_TEST_FAIL] = "Self test error",
	[ADIS16136_DIAG_STAT_FLASH_CHKSUM_FAIL] = "Flash checksum error",
	};

	static const struct adis_data adis16136_data = {
	.diag_stat_reg = ADIS16136_REG_DIAG_STAT,
	.glob_cmd_reg = ADIS16136_REG_GLOB_CMD,
	.msc_ctrl_reg = ADIS16136_REG_MSC_CTRL,

	.self_test_mask = ADIS16136_MSC_CTRL_SELF_TEST,
	.startup_delay = 80,

	.read_delay = 10,
	.write_delay = 10,

	.status_error_msgs = adis16136_status_error_msgs,
	.status_error_mask = BIT(ADIS16136_DIAG_STAT_FLASH_UPDATE_FAIL) \|
	BIT(ADIS16136_DIAG_STAT_SPI_FAIL) \|
	BIT(ADIS16136_DIAG_STAT_SELF_TEST_FAIL) \|
	BIT(ADIS16136_DIAG_STAT_FLASH_CHKSUM_FAIL),
	};

	enum adis16136_id {
	ID_ADIS16133,
	ID_ADIS16135,
	ID_ADIS16136,
	};

	static const struct adis16136_chip_info adis16136_chip_info[] = {
	[ID_ADIS16133] = {
	.precision = IIO_DEGREE_TO_RAD(1200),
	.fullscale = 24000,
	},
	[ID_ADIS16135] = {
	.precision = IIO_DEGREE_TO_RAD(300),
	.fullscale = 24000,
	},
	[ID_ADIS16136] = {
	.precision = IIO_DEGREE_TO_RAD(450),
	.fullscale = 24623,
	},
	};

	static int adis16136_probe(struct spi_device *spi)
	{
	const struct spi_device_id *id = spi_get_device_id(spi);
	struct adis16136 *adis16136;
	struct iio_dev *indio_dev;
	int ret;

	indio_dev = iio_device_alloc(sizeof(*adis16136));
	if (indio_dev == NULL)
	return -ENOMEM;

	spi_set_drvdata(spi, indio_dev);

	adis16136 = iio_priv(indio_dev);

	adis16136->chip_info = &adis16136_chip_info[id->driver_data];
	indio_dev->dev.parent = &spi->dev;
	indio_dev->name = spi_get_device_id(spi)->name;
	indio_dev->channels = adis16136_channels;
	indio_dev->num_channels = ARRAY_SIZE(adis16136_channels);
	indio_dev->info = &adis16136_info;
	indio_dev->modes = INDIO_DIRECT_MODE;

	ret = adis_init(&adis16136->adis, indio_dev, spi, &adis16136_data);
	if (ret)
	goto error_free_dev;

	ret = adis_setup_buffer_and_trigger(&adis16136->adis, indio_dev, NULL);
	if (ret)
	goto error_free_dev;

	ret = adis16136_initial_setup(indio_dev);
	if (ret)
	goto error_cleanup_buffer;

	ret = iio_device_register(indio_dev);
	if (ret)
	goto error_stop_device;

	adis16136_debugfs_init(indio_dev);

	return 0;

	error_stop_device:
	adis16136_stop_device(indio_dev);
	error_cleanup_buffer:
	adis_cleanup_buffer_and_trigger(&adis16136->adis, indio_dev);
	error_free_dev:
	iio_device_free(indio_dev);
	return ret;
	}

	static int adis16136_remove(struct spi_device *spi)
	{
	struct iio_dev *indio_dev = spi_get_drvdata(spi);
	struct adis16136 *adis16136 = iio_priv(indio_dev);

	iio_device_unregister(indio_dev);
	adis16136_stop_device(indio_dev);

	adis_cleanup_buffer_and_trigger(&adis16136->adis, indio_dev);

	iio_device_free(indio_dev);

	return 0;
	}

	static const struct spi_device_id adis16136_ids[] = {
	{ "adis16133", ID_ADIS16133 },
	{ "adis16135", ID_ADIS16135 },
	{ "adis16136", ID_ADIS16136 },
	{ }
	};
	MODULE_DEVICE_TABLE(spi, adis16136_ids);

	static struct spi_driver adis16136_driver = {
	.driver = {
	.name = "adis16136",
	.owner = THIS_MODULE,
	},
	.id_table = adis16136_ids,
	.probe = adis16136_probe,
	.remove = adis16136_remove,
	};
	module_spi_driver(adis16136_driver);

	MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
	MODULE_DESCRIPTION("Analog Devices ADIS16133/ADIS16135/ADIS16136 gyroscope driver");
	MODULE_LICENSE("GPL v2");