Re: [PATCH 7/7] iio:imu: Add support for the ADIS16480 and similar IMUs

[Jonathan Cameron <jic23@kernel.org>]

On 11/20/2012 01:36 PM, Lars-Peter Clausen wrote:
> This patch adds support for the ADIS16375, ADIS16480, ADIS16485, ADIS16488 6
> degree to 10 degree of freedom IMUs.

Only one minor nitpick.. docs in your adis library have slipped a little
behind the code with some new element struct adis_data not described
(they are obvious, but consistency is king ;)
>
> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Added to togreg branch of iio.git.

Lots of nice stuff in this series.  Thanks!

> ---
>  drivers/iio/imu/Kconfig      |  16 +
>  drivers/iio/imu/Makefile     |   2 +
>  drivers/iio/imu/adis.c       |   3 +
>  drivers/iio/imu/adis16480.c  | 925 +++++++++++++++++++++++++++++++++++++++++++
>  include/linux/iio/imu/adis.h |   4 +
>  5 files changed, 950 insertions(+)
>  create mode 100644 drivers/iio/imu/adis16480.c
>
> diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig
> index c24410c..8685a16 100644
> --- a/drivers/iio/imu/Kconfig
> +++ b/drivers/iio/imu/Kconfig
> @@ -1,3 +1,19 @@
> +#
> +# IIO imu drivers configuration
> +#
> +menu "Inertial measurement units"
> +
> +config ADIS16480
> +	tristate "Analog Devices ADIS16480 and similar IMU driver"
> +	depends on SPI
> +	select IIO_ADIS_LIB
> +	select IIO_ADIS_LIB_BUFFER if IIO_BUFFER
> +	help
> +	  Say yes here to build support for Analog Devices ADIS16375, ADIS16480,
> +	  ADIS16485, ADIS16488 inertial sensors.
> +
> +endmenu
> +
>  config IIO_ADIS_LIB
>  	tristate
>  	help
> diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile
> index 97676ab..cfe5763 100644
> --- a/drivers/iio/imu/Makefile
> +++ b/drivers/iio/imu/Makefile
> @@ -2,6 +2,8 @@
>  # Makefile for Inertial Measurement Units
>  #
>
> +obj-$(CONFIG_ADIS16480) += adis16480.o
> +
>  adis_lib-y += adis.o
>  adis_lib-$(CONFIG_IIO_ADIS_LIB_BUFFER) += adis_trigger.o
>  adis_lib-$(CONFIG_IIO_ADIS_LIB_BUFFER) += adis_buffer.o
> diff --git a/drivers/iio/imu/adis.c b/drivers/iio/imu/adis.c
> index c4ea04f..911255d 100644
> --- a/drivers/iio/imu/adis.c
> +++ b/drivers/iio/imu/adis.c
> @@ -238,6 +238,9 @@ int adis_enable_irq(struct adis *adis, bool enable)
>  	int ret = 0;
>  	uint16_t msc;
>
> +	if (adis->data->enable_irq)
> +		return adis->data->enable_irq(adis, enable);
> +
>  	ret = adis_read_reg_16(adis, adis->data->msc_ctrl_reg, &msc);
>  	if (ret)
>  		goto error_ret;
> diff --git a/drivers/iio/imu/adis16480.c b/drivers/iio/imu/adis16480.c
> new file mode 100644
> index 0000000..a058527
> --- /dev/null
> +++ b/drivers/iio/imu/adis16480.c
> @@ -0,0 +1,925 @@
> +/*
> + * ADIS16480 and similar IMUs driver
> + *
> + * Copyright 2012 Analog Devices Inc.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + */
> +
> +#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/iio/iio.h>
> +#include <linux/debugfs.h>
> +
> +#define ADIS16480_PAGE_SIZE 0x80
> +
> +#define ADIS16480_REG(page, reg) ((page) * ADIS16480_PAGE_SIZE + (reg))
> +
> +#define ADIS16480_REG_PAGE_ID 0x00 /* Same address on each page */
> +#define ADIS16480_REG_SEQ_CNT			ADIS16480_REG(0x00, 0x06)
> +#define ADIS16480_REG_SYS_E_FLA			ADIS16480_REG(0x00, 0x08)
> +#define ADIS16480_REG_DIAG_STS			ADIS16480_REG(0x00, 0x0A)
> +#define ADIS16480_REG_ALM_STS			ADIS16480_REG(0x00, 0x0C)
> +#define ADIS16480_REG_TEMP_OUT			ADIS16480_REG(0x00, 0x0E)
> +#define ADIS16480_REG_X_GYRO_OUT		ADIS16480_REG(0x00, 0x10)
> +#define ADIS16480_REG_Y_GYRO_OUT		ADIS16480_REG(0x00, 0x14)
> +#define ADIS16480_REG_Z_GYRO_OUT		ADIS16480_REG(0x00, 0x18)
> +#define ADIS16480_REG_X_ACCEL_OUT		ADIS16480_REG(0x00, 0x1C)
> +#define ADIS16480_REG_Y_ACCEL_OUT		ADIS16480_REG(0x00, 0x20)
> +#define ADIS16480_REG_Z_ACCEL_OUT		ADIS16480_REG(0x00, 0x24)
> +#define ADIS16480_REG_X_MAGN_OUT		ADIS16480_REG(0x00, 0x28)
> +#define ADIS16480_REG_Y_MAGN_OUT		ADIS16480_REG(0x00, 0x2A)
> +#define ADIS16480_REG_Z_MAGN_OUT		ADIS16480_REG(0x00, 0x2C)
> +#define ADIS16480_REG_BAROM_OUT			ADIS16480_REG(0x00, 0x2E)
> +#define ADIS16480_REG_X_DELTAANG_OUT		ADIS16480_REG(0x00, 0x40)
> +#define ADIS16480_REG_Y_DELTAANG_OUT		ADIS16480_REG(0x00, 0x44)
> +#define ADIS16480_REG_Z_DELTAANG_OUT		ADIS16480_REG(0x00, 0x48)
> +#define ADIS16480_REG_X_DELTAVEL_OUT		ADIS16480_REG(0x00, 0x4C)
> +#define ADIS16480_REG_Y_DELTAVEL_OUT		ADIS16480_REG(0x00, 0x50)
> +#define ADIS16480_REG_Z_DELTAVEL_OUT		ADIS16480_REG(0x00, 0x54)
> +#define ADIS16480_REG_PROD_ID			ADIS16480_REG(0x00, 0x7E)
> +
> +#define ADIS16480_REG_X_GYRO_SCALE		ADIS16480_REG(0x02, 0x04)
> +#define ADIS16480_REG_Y_GYRO_SCALE		ADIS16480_REG(0x02, 0x06)
> +#define ADIS16480_REG_Z_GYRO_SCALE		ADIS16480_REG(0x02, 0x08)
> +#define ADIS16480_REG_X_ACCEL_SCALE		ADIS16480_REG(0x02, 0x0A)
> +#define ADIS16480_REG_Y_ACCEL_SCALE		ADIS16480_REG(0x02, 0x0C)
> +#define ADIS16480_REG_Z_ACCEL_SCALE		ADIS16480_REG(0x02, 0x0E)
> +#define ADIS16480_REG_X_GYRO_BIAS		ADIS16480_REG(0x02, 0x10)
> +#define ADIS16480_REG_Y_GYRO_BIAS		ADIS16480_REG(0x02, 0x14)
> +#define ADIS16480_REG_Z_GYRO_BIAS		ADIS16480_REG(0x02, 0x18)
> +#define ADIS16480_REG_X_ACCEL_BIAS		ADIS16480_REG(0x02, 0x1C)
> +#define ADIS16480_REG_Y_ACCEL_BIAS		ADIS16480_REG(0x02, 0x20)
> +#define ADIS16480_REG_Z_ACCEL_BIAS		ADIS16480_REG(0x02, 0x24)
> +#define ADIS16480_REG_X_HARD_IRON		ADIS16480_REG(0x02, 0x28)
> +#define ADIS16480_REG_Y_HARD_IRON		ADIS16480_REG(0x02, 0x2A)
> +#define ADIS16480_REG_Z_HARD_IRON		ADIS16480_REG(0x02, 0x2C)
> +#define ADIS16480_REG_BAROM_BIAS		ADIS16480_REG(0x02, 0x40)
> +#define ADIS16480_REG_FLASH_CNT			ADIS16480_REG(0x02, 0x7C)
> +
> +#define ADIS16480_REG_GLOB_CMD			ADIS16480_REG(0x03, 0x02)
> +#define ADIS16480_REG_FNCTIO_CTRL		ADIS16480_REG(0x03, 0x06)
> +#define ADIS16480_REG_GPIO_CTRL			ADIS16480_REG(0x03, 0x08)
> +#define ADIS16480_REG_CONFIG			ADIS16480_REG(0x03, 0x0A)
> +#define ADIS16480_REG_DEC_RATE			ADIS16480_REG(0x03, 0x0C)
> +#define ADIS16480_REG_SLP_CNT			ADIS16480_REG(0x03, 0x10)
> +#define ADIS16480_REG_FILTER_BNK0		ADIS16480_REG(0x03, 0x16)
> +#define ADIS16480_REG_FILTER_BNK1		ADIS16480_REG(0x03, 0x18)
> +#define ADIS16480_REG_ALM_CNFG0			ADIS16480_REG(0x03, 0x20)
> +#define ADIS16480_REG_ALM_CNFG1			ADIS16480_REG(0x03, 0x22)
> +#define ADIS16480_REG_ALM_CNFG2			ADIS16480_REG(0x03, 0x24)
> +#define ADIS16480_REG_XG_ALM_MAGN		ADIS16480_REG(0x03, 0x28)
> +#define ADIS16480_REG_YG_ALM_MAGN		ADIS16480_REG(0x03, 0x2A)
> +#define ADIS16480_REG_ZG_ALM_MAGN		ADIS16480_REG(0x03, 0x2C)
> +#define ADIS16480_REG_XA_ALM_MAGN		ADIS16480_REG(0x03, 0x2E)
> +#define ADIS16480_REG_YA_ALM_MAGN		ADIS16480_REG(0x03, 0x30)
> +#define ADIS16480_REG_ZA_ALM_MAGN		ADIS16480_REG(0x03, 0x32)
> +#define ADIS16480_REG_XM_ALM_MAGN		ADIS16480_REG(0x03, 0x34)
> +#define ADIS16480_REG_YM_ALM_MAGN		ADIS16480_REG(0x03, 0x36)
> +#define ADIS16480_REG_ZM_ALM_MAGN		ADIS16480_REG(0x03, 0x38)
> +#define ADIS16480_REG_BR_ALM_MAGN		ADIS16480_REG(0x03, 0x3A)
> +#define ADIS16480_REG_FIRM_REV			ADIS16480_REG(0x03, 0x78)
> +#define ADIS16480_REG_FIRM_DM			ADIS16480_REG(0x03, 0x7A)
> +#define ADIS16480_REG_FIRM_Y			ADIS16480_REG(0x03, 0x7C)
> +
> +#define ADIS16480_REG_SERIAL_NUM		ADIS16480_REG(0x04, 0x20)
> +
> +/* Each filter coefficent bank spans two pages */
> +#define ADIS16480_FIR_COEF(page) (x < 60 ? ADIS16480_REG(page, (x) + 8) : \
> +		ADIS16480_REG((page) + 1, (x) - 60 + 8))
> +#define ADIS16480_FIR_COEF_A(x)			ADIS16480_FIR_COEF(0x05, (x))
> +#define ADIS16480_FIR_COEF_B(x)			ADIS16480_FIR_COEF(0x07, (x))
> +#define ADIS16480_FIR_COEF_C(x)			ADIS16480_FIR_COEF(0x09, (x))
> +#define ADIS16480_FIR_COEF_D(x)			ADIS16480_FIR_COEF(0x0B, (x))
> +
> +struct adis16480_chip_info {
> +	unsigned int num_channels;
> +	const struct iio_chan_spec *channels;
> +};
> +
> +struct adis16480 {
> +	const struct adis16480_chip_info *chip_info;
> +
> +	struct adis adis;
> +};
> +
> +#ifdef CONFIG_DEBUG_FS
> +
> +static ssize_t adis16480_show_firmware_revision(struct file *file,
> +		char __user *userbuf, size_t count, loff_t *ppos)
> +{
> +	struct adis16480 *adis16480 = file->private_data;
> +	char buf[6];
> +	size_t len;
> +	u16 rev;
> +	int ret;
> +
> +	ret = adis_read_reg_16(&adis16480->adis, ADIS16480_REG_FIRM_REV, &rev);
> +	if (ret < 0)
> +		return ret;
> +
> +	len = snprintf(buf, sizeof(buf), "%x.%x\n", rev >> 8, rev & 0xff);
> +
> +	return simple_read_from_buffer(userbuf, count, ppos, buf, len);
> +}
> +
> +static const struct file_operations adis16480_firmware_revision_fops = {
> +	.open = simple_open,
> +	.read = adis16480_show_firmware_revision,
> +	.llseek = default_llseek,
> +	.owner = THIS_MODULE,
> +};
> +
> +static ssize_t adis16480_show_firmware_date(struct file *file,
> +		char __user *userbuf, size_t count, loff_t *ppos)
> +{
> +	struct adis16480 *adis16480 = file->private_data;
> +	u16 md, year;
> +	char buf[12];
> +	size_t len;
> +	int ret;
> +
> +	ret = adis_read_reg_16(&adis16480->adis, ADIS16480_REG_FIRM_Y, &year);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = adis_read_reg_16(&adis16480->adis, ADIS16480_REG_FIRM_DM, &md);
> +	if (ret < 0)
> +		return ret;
> +
> +	len = snprintf(buf, sizeof(buf), "%.2x-%.2x-%.4x\n",
> +			md >> 8, md & 0xff, year);
> +
> +	return simple_read_from_buffer(userbuf, count, ppos, buf, len);
> +}
> +
> +static const struct file_operations adis16480_firmware_date_fops = {
> +	.open = simple_open,
> +	.read = adis16480_show_firmware_date,
> +	.llseek = default_llseek,
> +	.owner = THIS_MODULE,
> +};
> +
> +static int adis16480_show_serial_number(void *arg, u64 *val)
> +{
> +	struct adis16480 *adis16480 = arg;
> +	u16 serial;
> +	int ret;
> +
> +	ret = adis_read_reg_16(&adis16480->adis, ADIS16480_REG_SERIAL_NUM,
> +		&serial);
> +	if (ret < 0)
> +		return ret;
> +
> +	*val = serial;
> +
> +	return 0;
> +}
> +DEFINE_SIMPLE_ATTRIBUTE(adis16480_serial_number_fops,
> +	adis16480_show_serial_number, NULL, "0x%.4llx\n");
> +
> +static int adis16480_show_product_id(void *arg, u64 *val)
> +{
> +	struct adis16480 *adis16480 = arg;
> +	u16 prod_id;
> +	int ret;
> +
> +	ret = adis_read_reg_16(&adis16480->adis, ADIS16480_REG_PROD_ID,
> +		&prod_id);
> +	if (ret < 0)
> +		return ret;
> +
> +	*val = prod_id;
> +
> +	return 0;
> +}
> +DEFINE_SIMPLE_ATTRIBUTE(adis16480_product_id_fops,
> +	adis16480_show_product_id, NULL, "%llu\n");
> +
> +static int adis16480_show_flash_count(void *arg, u64 *val)
> +{
> +	struct adis16480 *adis16480 = arg;
> +	u32 flash_count;
> +	int ret;
> +
> +	ret = adis_read_reg_32(&adis16480->adis, ADIS16480_REG_FLASH_CNT,
> +		&flash_count);
> +	if (ret < 0)
> +		return ret;
> +
> +	*val = flash_count;
> +
> +	return 0;
> +}
> +DEFINE_SIMPLE_ATTRIBUTE(adis16480_flash_count_fops,
> +	adis16480_show_flash_count, NULL, "%lld\n");
> +
> +static int adis16480_debugfs_init(struct iio_dev *indio_dev)
> +{
> +	struct adis16480 *adis16480 = iio_priv(indio_dev);
> +
> +	debugfs_create_file("firmware_revision", 0400,
> +		indio_dev->debugfs_dentry, adis16480,
> +		&adis16480_firmware_revision_fops);
> +	debugfs_create_file("firmware_date", 0400, indio_dev->debugfs_dentry,
> +		adis16480, &adis16480_firmware_date_fops);
> +	debugfs_create_file("serial_number", 0400, indio_dev->debugfs_dentry,
> +		adis16480, &adis16480_serial_number_fops);
> +	debugfs_create_file("product_id", 0400, indio_dev->debugfs_dentry,
> +		adis16480, &adis16480_product_id_fops);
> +	debugfs_create_file("flash_count", 0400, indio_dev->debugfs_dentry,
> +		adis16480, &adis16480_flash_count_fops);
> +
> +	return 0;
> +}
> +
> +#else
> +
> +static int adis16480_debugfs_init(struct iio_dev *indio_dev)
> +{
> +	return 0;
> +}
> +
> +#endif
> +
> +static int adis16480_set_freq(struct adis16480 *st, unsigned int freq)
> +{
> +	unsigned int t;
> +
> +	t = 2460000 / freq;
> +	if (t > 2048)
> +		t = 2048;
> +
> +	if (t != 0)
> +		t--;
> +
> +	return adis_write_reg_16(&st->adis, ADIS16480_REG_DEC_RATE, t);
> +}
> +
> +static int adis16480_get_freq(struct adis16480 *st, unsigned int *freq)
> +{
> +	uint16_t t;
> +	int ret;
> +
> +	ret = adis_read_reg_16(&st->adis, ADIS16480_REG_DEC_RATE, &t);
> +	if (ret < 0)
> +		return ret;
> +
> +	*freq = 2460000 / (t + 1);
> +
> +	return 0;
> +}
> +
> +static ssize_t adis16480_read_frequency(struct device *dev,
> +		struct device_attribute *attr,
> +		char *buf)
> +{
> +	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
> +	struct adis16480 *st = iio_priv(indio_dev);
> +	unsigned int freq;
> +	int ret;
> +
> +	ret = adis16480_get_freq(st, &freq);
> +	if (ret < 0)
> +		return ret;
> +
> +	return sprintf(buf, "%d.%.3d\n", freq / 1000, freq % 1000);
> +}
> +
> +static ssize_t adis16480_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 adis16480 *st = iio_priv(indio_dev);
> +	int freq_int, freq_fract;
> +	long val;
> +	int ret;
> +
> +	ret = iio_str_to_fixpoint(buf, 100, &freq_int, &freq_fract);
> +	if (ret)
> +		return ret;
> +
> +	val = freq_int * 1000 + freq_fract;
> +
> +	if (val <= 0)
> +		return -EINVAL;
> +
> +	ret = adis16480_set_freq(st, val);
> +
> +	return ret ? ret : len;
> +}
> +
> +static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
> +			      adis16480_read_frequency,
> +			      adis16480_write_frequency);
> +
> +enum {
> +	ADIS16480_SCAN_GYRO_X,
> +	ADIS16480_SCAN_GYRO_Y,
> +	ADIS16480_SCAN_GYRO_Z,
> +	ADIS16480_SCAN_ACCEL_X,
> +	ADIS16480_SCAN_ACCEL_Y,
> +	ADIS16480_SCAN_ACCEL_Z,
> +	ADIS16480_SCAN_MAGN_X,
> +	ADIS16480_SCAN_MAGN_Y,
> +	ADIS16480_SCAN_MAGN_Z,
> +	ADIS16480_SCAN_BARO,
> +	ADIS16480_SCAN_TEMP,
> +};
> +
> +static const unsigned int adis16480_calibbias_regs[] = {
> +	[ADIS16480_SCAN_GYRO_X] = ADIS16480_REG_X_GYRO_BIAS,
> +	[ADIS16480_SCAN_GYRO_Y] = ADIS16480_REG_Y_GYRO_BIAS,
> +	[ADIS16480_SCAN_GYRO_Z] = ADIS16480_REG_Z_GYRO_BIAS,
> +	[ADIS16480_SCAN_ACCEL_X] = ADIS16480_REG_X_ACCEL_BIAS,
> +	[ADIS16480_SCAN_ACCEL_Y] = ADIS16480_REG_Y_ACCEL_BIAS,
> +	[ADIS16480_SCAN_ACCEL_Z] = ADIS16480_REG_Z_ACCEL_BIAS,
> +	[ADIS16480_SCAN_MAGN_X] = ADIS16480_REG_X_HARD_IRON,
> +	[ADIS16480_SCAN_MAGN_Y] = ADIS16480_REG_Y_HARD_IRON,
> +	[ADIS16480_SCAN_MAGN_Z] = ADIS16480_REG_Z_HARD_IRON,
> +	[ADIS16480_SCAN_BARO] = ADIS16480_REG_BAROM_BIAS,
> +};
> +
> +static const unsigned int adis16480_calibscale_regs[] = {
> +	[ADIS16480_SCAN_GYRO_X] = ADIS16480_REG_X_GYRO_SCALE,
> +	[ADIS16480_SCAN_GYRO_Y] = ADIS16480_REG_Y_GYRO_SCALE,
> +	[ADIS16480_SCAN_GYRO_Z] = ADIS16480_REG_Z_GYRO_SCALE,
> +	[ADIS16480_SCAN_ACCEL_X] = ADIS16480_REG_X_ACCEL_SCALE,
> +	[ADIS16480_SCAN_ACCEL_Y] = ADIS16480_REG_Y_ACCEL_SCALE,
> +	[ADIS16480_SCAN_ACCEL_Z] = ADIS16480_REG_Z_ACCEL_SCALE,
> +};
> +
> +static int adis16480_set_calibbias(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan, int bias)
> +{
> +	unsigned int reg = adis16480_calibbias_regs[chan->scan_index];
> +	struct adis16480 *st = iio_priv(indio_dev);
> +
> +	switch (chan->type) {
> +	case IIO_MAGN:
> +	case IIO_PRESSURE:
> +		if (bias < -0x8000 || bias >= 0x8000)
> +			return -EINVAL;
> +		return adis_write_reg_16(&st->adis, reg, bias);
> +	case IIO_ANGL_VEL:
> +	case IIO_ACCEL:
> +		return adis_write_reg_32(&st->adis, reg, bias);
> +	default:
> +		break;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int adis16480_get_calibbias(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan, int *bias)
> +{
> +	unsigned int reg = adis16480_calibbias_regs[chan->scan_index];
> +	struct adis16480 *st = iio_priv(indio_dev);
> +	uint16_t val16;
> +	uint32_t val32;
> +	int ret;
> +
> +	switch (chan->type) {
> +	case IIO_MAGN:
> +	case IIO_PRESSURE:
> +		ret = adis_read_reg_16(&st->adis, reg, &val16);
> +		*bias = sign_extend32(val16, 15);
> +		break;
> +	case IIO_ANGL_VEL:
> +	case IIO_ACCEL:
> +		ret = adis_read_reg_32(&st->adis, reg, &val32);
> +		*bias = sign_extend32(val32, 31);
> +		break;
> +	default:
> +			ret = -EINVAL;
> +	}
> +
> +	if (ret < 0)
> +		return ret;
> +
> +	return IIO_VAL_INT;
> +}
> +
> +static int adis16480_set_calibscale(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan, int scale)
> +{
> +	unsigned int reg = adis16480_calibscale_regs[chan->scan_index];
> +	struct adis16480 *st = iio_priv(indio_dev);
> +
> +	if (scale < -0x8000 || scale >= 0x8000)
> +		return -EINVAL;
> +
> +	return adis_write_reg_16(&st->adis, reg, scale);
> +}
> +
> +static int adis16480_get_calibscale(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan, int *scale)
> +{
> +	unsigned int reg = adis16480_calibscale_regs[chan->scan_index];
> +	struct adis16480 *st = iio_priv(indio_dev);
> +	uint16_t val16;
> +	int ret;
> +
> +	ret = adis_read_reg_16(&st->adis, reg, &val16);
> +	if (ret < 0)
> +		return ret;
> +
> +	*scale = sign_extend32(val16, 15);
> +	return IIO_VAL_INT;
> +}
> +
> +static const unsigned int adis16480_def_filter_freqs[] = {
> +	310,
> +	55,
> +	275,
> +	63,
> +};
> +
> +static const unsigned int ad16480_filter_data[][2] = {
> +	[ADIS16480_SCAN_GYRO_X]		= { ADIS16480_REG_FILTER_BNK0, 0 },
> +	[ADIS16480_SCAN_GYRO_Y]		= { ADIS16480_REG_FILTER_BNK0, 3 },
> +	[ADIS16480_SCAN_GYRO_Z]		= { ADIS16480_REG_FILTER_BNK0, 6 },
> +	[ADIS16480_SCAN_ACCEL_X]	= { ADIS16480_REG_FILTER_BNK0, 9 },
> +	[ADIS16480_SCAN_ACCEL_Y]	= { ADIS16480_REG_FILTER_BNK0, 12 },
> +	[ADIS16480_SCAN_ACCEL_Z]	= { ADIS16480_REG_FILTER_BNK1, 0 },
> +	[ADIS16480_SCAN_MAGN_X]		= { ADIS16480_REG_FILTER_BNK1, 3 },
> +	[ADIS16480_SCAN_MAGN_Y]		= { ADIS16480_REG_FILTER_BNK1, 6 },
> +	[ADIS16480_SCAN_MAGN_Z]		= { ADIS16480_REG_FILTER_BNK1, 9 },
> +};
> +
> +static int adis16480_get_filter_freq(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan, int *freq)
> +{
> +	struct adis16480 *st = iio_priv(indio_dev);
> +	unsigned int enable_mask, offset, reg;
> +	uint16_t val;
> +	int ret;
> +
> +	reg = ad16480_filter_data[chan->scan_index][0];
> +	offset = ad16480_filter_data[chan->scan_index][1];
> +	enable_mask = BIT(offset + 2);
> +
> +	ret = adis_read_reg_16(&st->adis, reg, &val);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (!(val & enable_mask))
> +		*freq = 0;
> +	else
> +		*freq = adis16480_def_filter_freqs[(val >> offset) & 0x3];
> +
> +	return IIO_VAL_INT;
> +}
> +
> +static int adis16480_set_filter_freq(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan, unsigned int freq)
> +{
> +	struct adis16480 *st = iio_priv(indio_dev);
> +	unsigned int enable_mask, offset, reg;
> +	unsigned int diff, best_diff;
> +	unsigned int i, best_freq;
> +	uint16_t val;
> +	int ret;
> +
> +	reg = ad16480_filter_data[chan->scan_index][0];
> +	offset = ad16480_filter_data[chan->scan_index][1];
> +	enable_mask = BIT(offset + 2);
> +
> +	ret = adis_read_reg_16(&st->adis, reg, &val);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (freq == 0) {
> +		val &= ~enable_mask;
> +	} else {
> +		best_freq = 0;
> +		best_diff = 310;
> +		for (i = 0; i < ARRAY_SIZE(adis16480_def_filter_freqs); i++) {
> +			if (adis16480_def_filter_freqs[i] >= freq) {
> +				diff = adis16480_def_filter_freqs[i] - freq;
> +				if (diff < best_diff) {
> +					best_diff = diff;
> +					best_freq = i;
> +				}
> +			}
> +		}
> +
> +		val &= ~(0x3 << offset);
> +		val |= best_freq << offset;
> +		val |= enable_mask;
> +	}
> +
> +	return adis_write_reg_16(&st->adis, reg, val);
> +}
> +
> +static int adis16480_read_raw(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan, int *val, int *val2, long info)
> +{
> +	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 = 0;
> +			*val2 = IIO_DEGREE_TO_RAD(20000); /* 0.02 degree/sec */
> +			return IIO_VAL_INT_PLUS_MICRO;
> +		case IIO_ACCEL:
> +			*val = 0;
> +			*val2 = IIO_G_TO_M_S_2(800); /* 0.8 mg */
> +			return IIO_VAL_INT_PLUS_MICRO;
> +		case IIO_MAGN:
> +			*val = 0;
> +			*val2 = 100; /* 0.0001 gauss */
> +			return IIO_VAL_INT_PLUS_MICRO;
> +		case IIO_TEMP:
> +			*val = 5;
> +			*val2 = 650000; /* 5.65 milli degree Celsius */
> +			return IIO_VAL_INT_PLUS_MICRO;
> +		case IIO_PRESSURE:
> +			*val = 0;
> +			*val2 = 4000; /* 40ubar = 0.004 kPa */
> +			return IIO_VAL_INT_PLUS_MICRO;
> +		default:
> +			return -EINVAL;
> +		}
> +	case IIO_CHAN_INFO_OFFSET:
> +		/* Only the temperature channel has a offset */
> +		*val = 4425; /* 25 degree Celsius = 0x0000 */
> +		return IIO_VAL_INT;
> +	case IIO_CHAN_INFO_CALIBBIAS:
> +		return adis16480_get_calibbias(indio_dev, chan, val);
> +	case IIO_CHAN_INFO_CALIBSCALE:
> +		return adis16480_get_calibscale(indio_dev, chan, val);
> +	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
> +		return adis16480_get_filter_freq(indio_dev, chan, val);
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static int adis16480_write_raw(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan, int val, int val2, long info)
> +{
> +	switch (info) {
> +	case IIO_CHAN_INFO_CALIBBIAS:
> +		return adis16480_set_calibbias(indio_dev, chan, val);
> +	case IIO_CHAN_INFO_CALIBSCALE:
> +		return adis16480_set_calibscale(indio_dev, chan, val);
> +	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
> +		return adis16480_set_filter_freq(indio_dev, chan, val);
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +#define ADIS16480_MOD_CHANNEL(_type, _mod, _address, _si, _info, _bits) \
> +	{ \
> +		.type = (_type), \
> +		.modified = 1, \
> +		.channel2 = (_mod), \
> +		.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
> +			IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT | \
> +			IIO_CHAN_INFO_SCALE_SHARED_BIT | \
> +			_info, \
> +		.address = (_address), \
> +		.scan_index = (_si), \
> +		.scan_type = { \
> +			.sign = 's', \
> +			.realbits = (_bits), \
> +			.storagebits = (_bits), \
> +			.endianness = IIO_BE, \
> +		}, \
> +	}
> +
> +#define ADIS16480_GYRO_CHANNEL(_mod) \
> +	ADIS16480_MOD_CHANNEL(IIO_ANGL_VEL, IIO_MOD_ ## _mod, \
> +	ADIS16480_REG_ ## _mod ## _GYRO_OUT, ADIS16480_SCAN_GYRO_ ## _mod, \
> +	IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SEPARATE_BIT | \
> +	IIO_CHAN_INFO_CALIBSCALE_SEPARATE_BIT, \
> +	32)
> +
> +#define ADIS16480_ACCEL_CHANNEL(_mod) \
> +	ADIS16480_MOD_CHANNEL(IIO_ACCEL, IIO_MOD_ ## _mod, \
> +	ADIS16480_REG_ ## _mod ## _ACCEL_OUT, ADIS16480_SCAN_ACCEL_ ## _mod, \
> +	IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SEPARATE_BIT | \
> +	IIO_CHAN_INFO_CALIBSCALE_SEPARATE_BIT, \
> +	32)
> +
> +#define ADIS16480_MAGN_CHANNEL(_mod) \
> +	ADIS16480_MOD_CHANNEL(IIO_MAGN, IIO_MOD_ ## _mod, \
> +	ADIS16480_REG_ ## _mod ## _MAGN_OUT, ADIS16480_SCAN_MAGN_ ## _mod, \
> +	IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SEPARATE_BIT, \
> +	16)
> +
> +#define ADIS16480_PRESSURE_CHANNEL() \
> +	{ \
> +		.type = IIO_PRESSURE, \
> +		.indexed = 1, \
> +		.channel = 0, \
> +		.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
> +			IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT | \
> +			IIO_CHAN_INFO_SCALE_SEPARATE_BIT, \
> +		.address = ADIS16480_REG_BAROM_OUT, \
> +		.scan_index = ADIS16480_SCAN_BARO, \
> +		.scan_type = { \
> +			.sign = 's', \
> +			.realbits = 32, \
> +			.storagebits = 32, \
> +			.endianness = IIO_BE, \
> +		}, \
> +	}
> +
> +#define ADIS16480_TEMP_CHANNEL() { \
> +		.type = IIO_TEMP, \
> +		.indexed = 1, \
> +		.channel = 0, \
> +		.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
> +			IIO_CHAN_INFO_SCALE_SEPARATE_BIT | \
> +			IIO_CHAN_INFO_OFFSET_SEPARATE_BIT, \
> +		.address = ADIS16480_REG_TEMP_OUT, \
> +		.scan_index = ADIS16480_SCAN_TEMP, \
> +		.scan_type = { \
> +			.sign = 's', \
> +			.realbits = 16, \
> +			.storagebits = 16, \
> +			.endianness = IIO_BE, \
> +		}, \
> +	}
> +
> +static const struct iio_chan_spec adis16480_channels[] = {
> +	ADIS16480_GYRO_CHANNEL(X),
> +	ADIS16480_GYRO_CHANNEL(Y),
> +	ADIS16480_GYRO_CHANNEL(Z),
> +	ADIS16480_ACCEL_CHANNEL(X),
> +	ADIS16480_ACCEL_CHANNEL(Y),
> +	ADIS16480_ACCEL_CHANNEL(Z),
> +	ADIS16480_MAGN_CHANNEL(X),
> +	ADIS16480_MAGN_CHANNEL(Y),
> +	ADIS16480_MAGN_CHANNEL(Z),
> +	ADIS16480_PRESSURE_CHANNEL(),
> +	ADIS16480_TEMP_CHANNEL(),
> +	IIO_CHAN_SOFT_TIMESTAMP(11)
> +};
> +
> +static const struct iio_chan_spec adis16485_channels[] = {
> +	ADIS16480_GYRO_CHANNEL(X),
> +	ADIS16480_GYRO_CHANNEL(Y),
> +	ADIS16480_GYRO_CHANNEL(Z),
> +	ADIS16480_ACCEL_CHANNEL(X),
> +	ADIS16480_ACCEL_CHANNEL(Y),
> +	ADIS16480_ACCEL_CHANNEL(Z),
> +	ADIS16480_TEMP_CHANNEL(),
> +	IIO_CHAN_SOFT_TIMESTAMP(7)
> +};
> +
> +enum adis16480_variant {
> +	ADIS16375,
> +	ADIS16480,
> +	ADIS16485,
> +	ADIS16488,
> +};
> +
> +static const struct adis16480_chip_info adis16480_chip_info[] = {
> +	[ADIS16375] = {
> +		.channels = adis16485_channels,
> +		.num_channels = ARRAY_SIZE(adis16485_channels),
> +	},
> +	[ADIS16480] = {
> +		.channels = adis16480_channels,
> +		.num_channels = ARRAY_SIZE(adis16480_channels),
> +	},
> +	[ADIS16485] = {
> +		.channels = adis16485_channels,
> +		.num_channels = ARRAY_SIZE(adis16485_channels),
> +	},
> +	[ADIS16488] = {
> +		.channels = adis16480_channels,
> +		.num_channels = ARRAY_SIZE(adis16480_channels),
> +	},
> +};
> +
> +static struct attribute *adis16480_attributes[] = {
> +	&iio_dev_attr_sampling_frequency.dev_attr.attr,
> +	NULL
> +};
> +
> +static const struct attribute_group adis16480_attribute_group = {
> +	.attrs = adis16480_attributes,
> +};
> +
> +static const struct iio_info adis16480_info = {
> +	.attrs = &adis16480_attribute_group,
> +	.read_raw = &adis16480_read_raw,
> +	.write_raw = &adis16480_write_raw,
> +	.update_scan_mode = adis_update_scan_mode,
> +	.driver_module = THIS_MODULE,
> +};
> +
> +static int adis16480_stop_device(struct iio_dev *indio_dev)
> +{
> +	struct adis16480 *st = iio_priv(indio_dev);
> +	int ret;
> +
> +	ret = adis_write_reg_16(&st->adis, ADIS16480_REG_SLP_CNT, BIT(9));
> +	if (ret)
> +		dev_err(&indio_dev->dev,
> +			"Could not power down device: %d\n", ret);
> +
> +	return ret;
> +}
> +
> +static int adis16480_enable_irq(struct adis *adis, bool enable)
> +{
> +	return adis_write_reg_16(adis, ADIS16480_REG_FNCTIO_CTRL,
> +		enable ? BIT(3) : 0);
> +}
> +
> +static int adis16480_initial_setup(struct iio_dev *indio_dev)
> +{
> +	struct adis16480 *st = iio_priv(indio_dev);
> +	uint16_t prod_id;
> +	unsigned int device_id;
> +	int ret;
> +
> +	adis_reset(&st->adis);
> +	msleep(70);
> +
> +	ret = adis_write_reg_16(&st->adis, ADIS16480_REG_GLOB_CMD, BIT(1));
> +	if (ret)
> +		return ret;
> +	msleep(30);
> +
> +	ret = adis_check_status(&st->adis);
> +	if (ret)
> +		return ret;
> +
> +	ret = adis_read_reg_16(&st->adis, ADIS16480_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;
> +}
> +
> +#define ADIS16480_DIAG_STAT_XGYRO_FAIL 0
> +#define ADIS16480_DIAG_STAT_YGYRO_FAIL 1
> +#define ADIS16480_DIAG_STAT_ZGYRO_FAIL 2
> +#define ADIS16480_DIAG_STAT_XACCL_FAIL 3
> +#define ADIS16480_DIAG_STAT_YACCL_FAIL 4
> +#define ADIS16480_DIAG_STAT_ZACCL_FAIL 5
> +#define ADIS16480_DIAG_STAT_XMAGN_FAIL 8
> +#define ADIS16480_DIAG_STAT_YMAGN_FAIL 9
> +#define ADIS16480_DIAG_STAT_ZMAGN_FAIL 10
> +#define ADIS16480_DIAG_STAT_BARO_FAIL 11
> +
> +static const char * const adis16480_status_error_msgs[] = {
> +	[ADIS16480_DIAG_STAT_XGYRO_FAIL] = "X-axis gyroscope self-test failure",
> +	[ADIS16480_DIAG_STAT_YGYRO_FAIL] = "Y-axis gyroscope self-test failure",
> +	[ADIS16480_DIAG_STAT_ZGYRO_FAIL] = "Z-axis gyroscope self-test failure",
> +	[ADIS16480_DIAG_STAT_XACCL_FAIL] = "X-axis accelerometer self-test failure",
> +	[ADIS16480_DIAG_STAT_YACCL_FAIL] = "Y-axis accelerometer self-test failure",
> +	[ADIS16480_DIAG_STAT_ZACCL_FAIL] = "Z-axis accelerometer self-test failure",
> +	[ADIS16480_DIAG_STAT_XMAGN_FAIL] = "X-axis magnetometer self-test failure",
> +	[ADIS16480_DIAG_STAT_YMAGN_FAIL] = "Y-axis magnetometer self-test failure",
> +	[ADIS16480_DIAG_STAT_ZMAGN_FAIL] = "Z-axis magnetometer self-test failure",
> +	[ADIS16480_DIAG_STAT_BARO_FAIL] = "Barometer self-test failure",
> +};
> +
> +static const struct adis_data adis16480_data = {
> +	.diag_stat_reg = ADIS16480_REG_DIAG_STS,
> +	.glob_cmd_reg = ADIS16480_REG_GLOB_CMD,
> +	.has_paging = true,
> +
> +	.read_delay = 5,
> +	.write_delay = 5,
> +
> +	.status_error_msgs = adis16480_status_error_msgs,
> +	.status_error_mask = BIT(ADIS16480_DIAG_STAT_XGYRO_FAIL) |
> +		BIT(ADIS16480_DIAG_STAT_YGYRO_FAIL) |
> +		BIT(ADIS16480_DIAG_STAT_ZGYRO_FAIL) |
> +		BIT(ADIS16480_DIAG_STAT_XACCL_FAIL) |
> +		BIT(ADIS16480_DIAG_STAT_YACCL_FAIL) |
> +		BIT(ADIS16480_DIAG_STAT_ZACCL_FAIL) |
> +		BIT(ADIS16480_DIAG_STAT_XMAGN_FAIL) |
> +		BIT(ADIS16480_DIAG_STAT_YMAGN_FAIL) |
> +		BIT(ADIS16480_DIAG_STAT_ZMAGN_FAIL) |
> +		BIT(ADIS16480_DIAG_STAT_BARO_FAIL),
> +
> +	.enable_irq = adis16480_enable_irq,
> +};
> +
> +static int __devinit adis16480_probe(struct spi_device *spi)
> +{
> +	const struct spi_device_id *id = spi_get_device_id(spi);
> +	struct iio_dev *indio_dev;
> +	struct adis16480 *st;
> +	int ret;
> +
> +	indio_dev = iio_device_alloc(sizeof(*st));
> +	if (indio_dev == NULL)
> +		return -ENOMEM;
> +
> +	spi_set_drvdata(spi, indio_dev);
> +
> +	st = iio_priv(indio_dev);
> +
> +	st->chip_info = &adis16480_chip_info[id->driver_data];
> +	indio_dev->dev.parent = &spi->dev;
> +	indio_dev->name = spi_get_device_id(spi)->name;
> +	indio_dev->channels = st->chip_info->channels;
> +	indio_dev->num_channels = st->chip_info->num_channels;
> +	indio_dev->info = &adis16480_info;
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +
> +	ret = adis_init(&st->adis, indio_dev, spi, &adis16480_data);
> +	if (ret)
> +		goto error_free_dev;
> +
> +	ret = adis_setup_buffer_and_trigger(&st->adis, indio_dev, NULL);
> +	if (ret)
> +		goto error_free_dev;
> +
> +	ret = adis16480_initial_setup(indio_dev);
> +	if (ret)
> +		goto error_cleanup_buffer;
> +
> +	ret = iio_device_register(indio_dev);
> +	if (ret)
> +		goto error_stop_device;
> +
> +	adis16480_debugfs_init(indio_dev);
> +
> +	return 0;
> +
> +error_stop_device:
> +	adis16480_stop_device(indio_dev);
> +error_cleanup_buffer:
> +	adis_cleanup_buffer_and_trigger(&st->adis, indio_dev);
> +error_free_dev:
> +	iio_device_free(indio_dev);
> +	return ret;
> +}
> +
> +static int __devexit adis16480_remove(struct spi_device *spi)
> +{
> +	struct iio_dev *indio_dev = spi_get_drvdata(spi);
> +	struct adis16480 *st = iio_priv(indio_dev);
> +
> +	iio_device_unregister(indio_dev);
> +	adis16480_stop_device(indio_dev);
> +
> +	adis_cleanup_buffer_and_trigger(&st->adis, indio_dev);
> +
> +	iio_device_free(indio_dev);
> +
> +	return 0;
> +}
> +
> +static const struct spi_device_id adis16480_ids[] = {
> +	{ "adis16375", ADIS16375 },
> +	{ "adis16480", ADIS16480 },
> +	{ "adis16485", ADIS16485 },
> +	{ "adis16488", ADIS16488 },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(spi, adis16480_ids);
> +
> +static struct spi_driver adis16480_driver = {
> +	.driver = {
> +		.name = "adis16480",
> +		.owner = THIS_MODULE,
> +	},
> +	.id_table = adis16480_ids,
> +	.probe = adis16480_probe,
> +	.remove = __devexit_p(adis16480_remove),
> +};
> +module_spi_driver(adis16480_driver);
> +
> +MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
> +MODULE_DESCRIPTION("Analog Devices ADIS16480 IMU driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/include/linux/iio/imu/adis.h b/include/linux/iio/imu/adis.h
> index e82cd08..ff781dc 100644
> --- a/include/linux/iio/imu/adis.h
> +++ b/include/linux/iio/imu/adis.h
> @@ -20,6 +20,8 @@
>  #define ADIS_PAGE_SIZE 0x80
>  #define ADIS_REG_PAGE_ID 0x00
>
> +struct adis;
> +
>  /**
>   * struct adis_data - ADIS chip variant specific data
>   * @read_delay: SPI delay for read operations in us
> @@ -44,6 +46,8 @@ struct adis_data {
>  	const char * const *status_error_msgs;
>  	unsigned int status_error_mask;
>
> +	int (*enable_irq)(struct adis *adis, bool enable);
> +
>  	bool has_paging;
>  };
>
>