[deliverable/linux.git] / drivers / staging / iio / gyro / adis16260_core.c

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

#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/gpio.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 "../iio.h"
#include "../sysfs.h"
#include "../ring_generic.h"
#include "../adc/adc.h"
#include "gyro.h"

#include "adis16260.h"

#define DRIVER_NAME		"adis16260"

static int adis16260_check_status(struct device *dev);

/**
 * adis16260_spi_write_reg_8() - write single byte to a register
 * @dev: device associated with child of actual device (iio_dev or iio_trig)
 * @reg_address: the address of the register to be written
 * @val: the value to write
 **/
static int adis16260_spi_write_reg_8(struct device *dev,
		u8 reg_address,
		u8 val)
{
	int ret;
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct adis16260_state *st = iio_dev_get_devdata(indio_dev);

	mutex_lock(&st->buf_lock);
	st->tx[0] = ADIS16260_WRITE_REG(reg_address);
	st->tx[1] = val;

	ret = spi_write(st->us, st->tx, 2);
	mutex_unlock(&st->buf_lock);

	return ret;
}

/**
 * adis16260_spi_write_reg_16() - write 2 bytes to a pair of registers
 * @dev: device associated with child of actual device (iio_dev or iio_trig)
 * @reg_address: the address of the lower of the two registers. Second register
 *               is assumed to have address one greater.
 * @val: value to be written
 **/
static int adis16260_spi_write_reg_16(struct device *dev,
		u8 lower_reg_address,
		u16 value)
{
	int ret;
	struct spi_message msg;
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct adis16260_state *st = iio_dev_get_devdata(indio_dev);
	struct spi_transfer xfers[] = {
		{
			.tx_buf = st->tx,
			.bits_per_word = 8,
			.len = 2,
			.cs_change = 1,
			.delay_usecs = 20,
		}, {
			.tx_buf = st->tx + 2,
			.bits_per_word = 8,
			.len = 2,
			.cs_change = 1,
			.delay_usecs = 20,
		},
	};

	mutex_lock(&st->buf_lock);
	st->tx[0] = ADIS16260_WRITE_REG(lower_reg_address);
	st->tx[1] = value & 0xFF;
	st->tx[2] = ADIS16260_WRITE_REG(lower_reg_address + 1);
	st->tx[3] = (value >> 8) & 0xFF;

	spi_message_init(&msg);
	spi_message_add_tail(&xfers[0], &msg);
	spi_message_add_tail(&xfers[1], &msg);
	ret = spi_sync(st->us, &msg);
	mutex_unlock(&st->buf_lock);

	return ret;
}

/**
 * adis16260_spi_read_reg_16() - read 2 bytes from a 16-bit register
 * @dev: device associated with child of actual device (iio_dev or iio_trig)
 * @reg_address: the address of the lower of the two registers. Second register
 *               is assumed to have address one greater.
 * @val: somewhere to pass back the value read
 **/
static int adis16260_spi_read_reg_16(struct device *dev,
		u8 lower_reg_address,
		u16 *val)
{
	struct spi_message msg;
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct adis16260_state *st = iio_dev_get_devdata(indio_dev);
	int ret;
	struct spi_transfer xfers[] = {
		{
			.tx_buf = st->tx,
			.bits_per_word = 8,
			.len = 2,
			.cs_change = 1,
			.delay_usecs = 30,
		}, {
			.rx_buf = st->rx,
			.bits_per_word = 8,
			.len = 2,
			.cs_change = 1,
			.delay_usecs = 30,
		},
	};

	mutex_lock(&st->buf_lock);
	st->tx[0] = ADIS16260_READ_REG(lower_reg_address);
	st->tx[1] = 0;
	st->tx[2] = 0;
	st->tx[3] = 0;

	spi_message_init(&msg);
	spi_message_add_tail(&xfers[0], &msg);
	spi_message_add_tail(&xfers[1], &msg);
	ret = spi_sync(st->us, &msg);
	if (ret) {
		dev_err(&st->us->dev,
			"problem when reading 16 bit register 0x%02X",
			lower_reg_address);
		goto error_ret;
	}
	*val = (st->rx[0] << 8) | st->rx[1];

error_ret:
	mutex_unlock(&st->buf_lock);
	return ret;
}

static ssize_t adis16260_spi_read_signed(struct device *dev,
		struct device_attribute *attr,
		char *buf,
		unsigned bits)
{
	int ret;
	s16 val = 0;
	unsigned shift = 16 - bits;
	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);

	ret = adis16260_spi_read_reg_16(dev, this_attr->address, (u16 *)&val);
	if (ret)
		return ret;

	if (val & ADIS16260_ERROR_ACTIVE)
		adis16260_check_status(dev);
	val = ((s16)(val << shift) >> shift);
	return sprintf(buf, "%d\n", val);
}

static ssize_t adis16260_read_12bit_unsigned(struct device *dev,
		struct device_attribute *attr,
		char *buf)
{
	int ret;
	u16 val = 0;
	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);

	ret = adis16260_spi_read_reg_16(dev, this_attr->address, &val);
	if (ret)
		return ret;

	if (val & ADIS16260_ERROR_ACTIVE)
		adis16260_check_status(dev);

	return sprintf(buf, "%u\n", val & 0x0FFF);
}

static ssize_t adis16260_read_12bit_signed(struct device *dev,
		struct device_attribute *attr,
		char *buf)
{
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	ssize_t ret;

	/* Take the iio_dev status lock */
	mutex_lock(&indio_dev->mlock);
	ret =  adis16260_spi_read_signed(dev, attr, buf, 12);
	mutex_unlock(&indio_dev->mlock);

	return ret;
}

static ssize_t adis16260_read_14bit_signed(struct device *dev,
		struct device_attribute *attr,
		char *buf)
{
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	ssize_t ret;

	/* Take the iio_dev status lock */
	mutex_lock(&indio_dev->mlock);
	ret =  adis16260_spi_read_signed(dev, attr, buf, 14);
	mutex_unlock(&indio_dev->mlock);

	return ret;
}

static ssize_t adis16260_write_16bit(struct device *dev,
		struct device_attribute *attr,
		const char *buf,
		size_t len)
{
	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	int ret;
	long val;

	ret = strict_strtol(buf, 10, &val);
	if (ret)
		goto error_ret;
	ret = adis16260_spi_write_reg_16(dev, this_attr->address, val);

error_ret:
	return ret ? ret : len;
}

static ssize_t adis16260_read_frequency(struct device *dev,
		struct device_attribute *attr,
		char *buf)
{
	int ret, len = 0;
	u16 t;
	int sps;
	ret = adis16260_spi_read_reg_16(dev,
			ADIS16260_SMPL_PRD,
			&t);
	if (ret)
		return ret;
	sps =  (t & ADIS16260_SMPL_PRD_TIME_BASE) ? 66 : 2048;
	sps /= (t & ADIS16260_SMPL_PRD_DIV_MASK) + 1;
	len = sprintf(buf, "%d SPS\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_get_drvdata(dev);
	struct adis16260_state *st = iio_dev_get_devdata(indio_dev);
	long val;
	int ret;
	u8 t;

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

	mutex_lock(&indio_dev->mlock);

	t = (2048 / val);
	if (t > 0)
		t--;
	t &= ADIS16260_SMPL_PRD_DIV_MASK;
	if ((t & ADIS16260_SMPL_PRD_DIV_MASK) >= 0x0A)
		st->us->max_speed_hz = ADIS16260_SPI_SLOW;
	else
		st->us->max_speed_hz = ADIS16260_SPI_FAST;

	ret = adis16260_spi_write_reg_8(dev,
			ADIS16260_SMPL_PRD,
			t);

	mutex_unlock(&indio_dev->mlock);

	return ret ? ret : len;
}

static int adis16260_reset(struct device *dev)
{
	int ret;
	ret = adis16260_spi_write_reg_8(dev,
			ADIS16260_GLOB_CMD,
			ADIS16260_GLOB_CMD_SW_RESET);
	if (ret)
		dev_err(dev, "problem resetting device");

	return ret;
}

static ssize_t adis16260_write_reset(struct device *dev,
		struct device_attribute *attr,
		const char *buf, size_t len)
{
	if (len < 1)
		return -EINVAL;
	switch (buf[0]) {
	case '1':
	case 'y':
	case 'Y':
		return adis16260_reset(dev);
	}
	return -EINVAL;
}

int adis16260_set_irq(struct device *dev, bool enable)
{
	int ret;
	u16 msc;
	ret = adis16260_spi_read_reg_16(dev, ADIS16260_MSC_CTRL, &msc);
	if (ret)
		goto error_ret;

	msc |= ADIS16260_MSC_CTRL_DATA_RDY_POL_HIGH;
	if (enable)
		msc |= ADIS16260_MSC_CTRL_DATA_RDY_EN;
	else
		msc &= ~ADIS16260_MSC_CTRL_DATA_RDY_EN;

	ret = adis16260_spi_write_reg_16(dev, ADIS16260_MSC_CTRL, msc);
	if (ret)
		goto error_ret;

error_ret:
	return ret;
}

/* Power down the device */
static int adis16260_stop_device(struct device *dev)
{
	int ret;
	u16 val = ADIS16260_SLP_CNT_POWER_OFF;

	ret = adis16260_spi_write_reg_16(dev, ADIS16260_SLP_CNT, val);
	if (ret)
		dev_err(dev, "problem with turning device off: SLP_CNT");

	return ret;
}

static int adis16260_self_test(struct device *dev)
{
	int ret;
	ret = adis16260_spi_write_reg_16(dev,
			ADIS16260_MSC_CTRL,
			ADIS16260_MSC_CTRL_MEM_TEST);
	if (ret) {
		dev_err(dev, "problem starting self test");
		goto err_ret;
	}

	adis16260_check_status(dev);

err_ret:
	return ret;
}

static int adis16260_check_status(struct device *dev)
{
	u16 status;
	int ret;

	ret = adis16260_spi_read_reg_16(dev, ADIS16260_DIAG_STAT, &status);

	if (ret < 0) {
		dev_err(dev, "Reading status failed\n");
		goto error_ret;
	}
	ret = status & 0x7F;
	if (status & ADIS16260_DIAG_STAT_FLASH_CHK)
		dev_err(dev, "Flash checksum error\n");
	if (status & ADIS16260_DIAG_STAT_SELF_TEST)
		dev_err(dev, "Self test error\n");
	if (status & ADIS16260_DIAG_STAT_OVERFLOW)
		dev_err(dev, "Sensor overrange\n");
	if (status & ADIS16260_DIAG_STAT_SPI_FAIL)
		dev_err(dev, "SPI failure\n");
	if (status & ADIS16260_DIAG_STAT_FLASH_UPT)
		dev_err(dev, "Flash update failed\n");
	if (status & ADIS16260_DIAG_STAT_POWER_HIGH)
		dev_err(dev, "Power supply above 5.25V\n");
	if (status & ADIS16260_DIAG_STAT_POWER_LOW)
		dev_err(dev, "Power supply below 4.75V\n");

error_ret:
	return ret;
}

static int adis16260_initial_setup(struct adis16260_state *st)
{
	int ret;
	struct device *dev = &st->indio_dev->dev;

	/* Disable IRQ */
	ret = adis16260_set_irq(dev, false);
	if (ret) {
		dev_err(dev, "disable irq failed");
		goto err_ret;
	}

	/* Do self test */
	ret = adis16260_self_test(dev);
	if (ret) {
		dev_err(dev, "self test failure");
		goto err_ret;
	}

	/* Read status register to check the result */
	ret = adis16260_check_status(dev);
	if (ret) {
		adis16260_reset(dev);
		dev_err(dev, "device not playing ball -> reset");
		msleep(ADIS16260_STARTUP_DELAY);
		ret = adis16260_check_status(dev);
		if (ret) {
			dev_err(dev, "giving up");
			goto err_ret;
		}
	}

	printk(KERN_INFO DRIVER_NAME ": at CS%d (irq %d)\n",
			st->us->chip_select, st->us->irq);

err_ret:
	return ret;
}

static IIO_DEV_ATTR_IN_NAMED_RAW(0, supply,
				adis16260_read_12bit_unsigned,
				ADIS16260_SUPPLY_OUT);
static IIO_CONST_ATTR_IN_NAMED_SCALE(0, supply, "0.0018315");

static IIO_DEV_ATTR_GYRO(adis16260_read_14bit_signed,
		ADIS16260_GYRO_OUT);
static IIO_CONST_ATTR_GYRO_SCALE("0.00127862821");
static IIO_DEV_ATTR_GYRO_CALIBSCALE(S_IWUSR | S_IRUGO,
		adis16260_read_14bit_signed,
		adis16260_write_16bit,
		ADIS16260_GYRO_SCALE);
static IIO_DEV_ATTR_GYRO_CALIBBIAS(S_IWUSR | S_IRUGO,
		adis16260_read_12bit_signed,
		adis16260_write_16bit,
		ADIS16260_GYRO_OFF);

static IIO_DEV_ATTR_TEMP_RAW(adis16260_read_12bit_unsigned);
static IIO_CONST_ATTR_TEMP_OFFSET("25");
static IIO_CONST_ATTR_TEMP_SCALE("0.1453");

static IIO_DEV_ATTR_IN_RAW(1, adis16260_read_12bit_unsigned,
		ADIS16260_AUX_ADC);
static IIO_CONST_ATTR(in1_scale, "0.0006105");

static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
		adis16260_read_frequency,
		adis16260_write_frequency);
static IIO_DEV_ATTR_ANGL(adis16260_read_14bit_signed,
		ADIS16260_ANGL_OUT);

static IIO_DEVICE_ATTR(reset, S_IWUSR, NULL, adis16260_write_reset, 0);

static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("256 2048");

static IIO_CONST_ATTR_NAME("adis16260");

static struct attribute *adis16260_event_attributes[] = {
	NULL
};

static struct attribute_group adis16260_event_attribute_group = {
	.attrs = adis16260_event_attributes,
};

static struct attribute *adis16260_attributes[] = {
	&iio_dev_attr_in0_supply_raw.dev_attr.attr,
	&iio_const_attr_in0_supply_scale.dev_attr.attr,
	&iio_dev_attr_gyro_raw.dev_attr.attr,
	&iio_const_attr_gyro_scale.dev_attr.attr,
	&iio_dev_attr_gyro_calibscale.dev_attr.attr,
	&iio_dev_attr_gyro_calibbias.dev_attr.attr,
	&iio_dev_attr_angl_raw.dev_attr.attr,
	&iio_dev_attr_temp_raw.dev_attr.attr,
	&iio_const_attr_temp_offset.dev_attr.attr,
	&iio_const_attr_temp_scale.dev_attr.attr,
	&iio_dev_attr_in1_raw.dev_attr.attr,
	&iio_const_attr_in1_scale.dev_attr.attr,
	&iio_dev_attr_sampling_frequency.dev_attr.attr,
	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
	&iio_dev_attr_reset.dev_attr.attr,
	&iio_const_attr_name.dev_attr.attr,
	NULL
};

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

static int __devinit adis16260_probe(struct spi_device *spi)
{
	int ret, regdone = 0;
	struct adis16260_state *st = kzalloc(sizeof *st, GFP_KERNEL);
	if (!st) {
		ret =  -ENOMEM;
		goto error_ret;
	}
	/* this is only used for removal purposes */
	spi_set_drvdata(spi, st);

	/* Allocate the comms buffers */
	st->rx = kzalloc(sizeof(*st->rx)*ADIS16260_MAX_RX, GFP_KERNEL);
	if (st->rx == NULL) {
		ret = -ENOMEM;
		goto error_free_st;
	}
	st->tx = kzalloc(sizeof(*st->tx)*ADIS16260_MAX_TX, GFP_KERNEL);
	if (st->tx == NULL) {
		ret = -ENOMEM;
		goto error_free_rx;
	}
	st->us = spi;
	mutex_init(&st->buf_lock);
	/* setup the industrialio driver allocated elements */
	st->indio_dev = iio_allocate_device();
	if (st->indio_dev == NULL) {
		ret = -ENOMEM;
		goto error_free_tx;
	}

	st->indio_dev->dev.parent = &spi->dev;
	st->indio_dev->num_interrupt_lines = 1;
	st->indio_dev->event_attrs = &adis16260_event_attribute_group;
	st->indio_dev->attrs = &adis16260_attribute_group;
	st->indio_dev->dev_data = (void *)(st);
	st->indio_dev->driver_module = THIS_MODULE;
	st->indio_dev->modes = INDIO_DIRECT_MODE;

	ret = adis16260_configure_ring(st->indio_dev);
	if (ret)
		goto error_free_dev;

	ret = iio_device_register(st->indio_dev);
	if (ret)
		goto error_unreg_ring_funcs;
	regdone = 1;
	ret = iio_ring_buffer_register(st->indio_dev->ring, 0);
	if (ret) {
		printk(KERN_ERR "failed to initialize the ring\n");
		goto error_unreg_ring_funcs;
	}

	if (spi->irq) {
		ret = iio_register_interrupt_line(spi->irq,
				st->indio_dev,
				0,
				IRQF_TRIGGER_RISING,
				"adis16260");
		if (ret)
			goto error_uninitialize_ring;

		ret = adis16260_probe_trigger(st->indio_dev);
		if (ret)
			goto error_unregister_line;
	}

	/* Get the device into a sane initial state */
	ret = adis16260_initial_setup(st);
	if (ret)
		goto error_remove_trigger;
	return 0;

error_remove_trigger:
	adis16260_remove_trigger(st->indio_dev);
error_unregister_line:
	if (spi->irq)
		iio_unregister_interrupt_line(st->indio_dev, 0);
error_uninitialize_ring:
	iio_ring_buffer_unregister(st->indio_dev->ring);
error_unreg_ring_funcs:
	adis16260_unconfigure_ring(st->indio_dev);
error_free_dev:
	if (regdone)
		iio_device_unregister(st->indio_dev);
	else
		iio_free_device(st->indio_dev);
error_free_tx:
	kfree(st->tx);
error_free_rx:
	kfree(st->rx);
error_free_st:
	kfree(st);
error_ret:
	return ret;
}

static int adis16260_remove(struct spi_device *spi)
{
	int ret;
	struct adis16260_state *st = spi_get_drvdata(spi);
	struct iio_dev *indio_dev = st->indio_dev;

	ret = adis16260_stop_device(&(indio_dev->dev));
	if (ret)
		goto err_ret;

	flush_scheduled_work();

	adis16260_remove_trigger(indio_dev);
	if (spi->irq)
		iio_unregister_interrupt_line(indio_dev, 0);

	iio_ring_buffer_unregister(st->indio_dev->ring);
	iio_device_unregister(indio_dev);
	adis16260_unconfigure_ring(indio_dev);
	kfree(st->tx);
	kfree(st->rx);
	kfree(st);

err_ret:
	return ret;
}

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

static __init int adis16260_init(void)
{
	return spi_register_driver(&adis16260_driver);
}
module_init(adis16260_init);

static __exit void adis16260_exit(void)
{
	spi_unregister_driver(&adis16260_driver);
}
module_exit(adis16260_exit);

MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
MODULE_DESCRIPTION("Analog Devices ADIS16260/5 Digital Gyroscope Sensor");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
089a4198 BS	1	/*
	2	* ADIS16260 Programmable Digital Gyroscope Sensor Driver
	3	*
	4	* Copyright 2010 Analog Devices Inc.
	5	*
	6	* Licensed under the GPL-2 or later.
	7	*/
	8
	9	#include <linux/interrupt.h>
	10	#include <linux/irq.h>
	11	#include <linux/gpio.h>
	12	#include <linux/delay.h>
	13	#include <linux/mutex.h>
	14	#include <linux/device.h>
	15	#include <linux/kernel.h>
	16	#include <linux/spi/spi.h>
1cb6c1f5	17	#include <linux/slab.h>
089a4198 BS	18	#include <linux/sysfs.h>
	19	#include <linux/list.h>
	20
	21	#include "../iio.h"
	22	#include "../sysfs.h"
2662051e	23	#include "../ring_generic.h"
089a4198 BS	24	#include "../adc/adc.h"
	25	#include "gyro.h"
	26
	27	#include "adis16260.h"
	28
	29	#define DRIVER_NAME "adis16260"
	30
	31	static int adis16260_check_status(struct device *dev);
	32
	33	/**
	34	* adis16260_spi_write_reg_8() - write single byte to a register
	35	* @dev: device associated with child of actual device (iio_dev or iio_trig)
	36	* @reg_address: the address of the register to be written
	37	* @val: the value to write
	38	**/
	39	static int adis16260_spi_write_reg_8(struct device *dev,
	40	u8 reg_address,
	41	u8 val)
	42	{
	43	int ret;
	44	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	45	struct adis16260_state *st = iio_dev_get_devdata(indio_dev);
	46
	47	mutex_lock(&st->buf_lock);
	48	st->tx[0] = ADIS16260_WRITE_REG(reg_address);
	49	st->tx[1] = val;
	50
	51	ret = spi_write(st->us, st->tx, 2);
	52	mutex_unlock(&st->buf_lock);
	53
	54	return ret;
	55	}
	56
	57	/**
	58	* adis16260_spi_write_reg_16() - write 2 bytes to a pair of registers
	59	* @dev: device associated with child of actual device (iio_dev or iio_trig)
	60	* @reg_address: the address of the lower of the two registers. Second register
	61	* is assumed to have address one greater.
	62	* @val: value to be written
	63	**/
	64	static int adis16260_spi_write_reg_16(struct device *dev,
	65	u8 lower_reg_address,
	66	u16 value)
	67	{
	68	int ret;
	69	struct spi_message msg;
	70	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	71	struct adis16260_state *st = iio_dev_get_devdata(indio_dev);
	72	struct spi_transfer xfers[] = {
	73	{
	74	.tx_buf = st->tx,
	75	.bits_per_word = 8,
	76	.len = 2,
	77	.cs_change = 1,
	78	.delay_usecs = 20,
	79	}, {
	80	.tx_buf = st->tx + 2,
	81	.bits_per_word = 8,
	82	.len = 2,
	83	.cs_change = 1,
	84	.delay_usecs = 20,
	85	},
	86	};
	87
88	mutex_lock(&st->buf_lock);
89	st->tx[0] = ADIS16260_WRITE_REG(lower_reg_address);
90	st->tx[1] = value & 0xFF;
91	st->tx[2] = ADIS16260_WRITE_REG(lower_reg_address + 1);
92	st->tx[3] = (value >> 8) & 0xFF;
93
94	spi_message_init(&msg);
95	spi_message_add_tail(&xfers[0], &msg);
96	spi_message_add_tail(&xfers[1], &msg);
97	ret = spi_sync(st->us, &msg);
98	mutex_unlock(&st->buf_lock);
99
100	return ret;
101	}
102
103	/**
104	* adis16260_spi_read_reg_16() - read 2 bytes from a 16-bit register
105	* @dev: device associated with child of actual device (iio_dev or iio_trig)
106	* @reg_address: the address of the lower of the two registers. Second register
107	* is assumed to have address one greater.
108	* @val: somewhere to pass back the value read
109	**/
110	static int adis16260_spi_read_reg_16(struct device *dev,
111	u8 lower_reg_address,
112	u16 *val)
113	{
114	struct spi_message msg;
115	struct iio_dev *indio_dev = dev_get_drvdata(dev);
116	struct adis16260_state *st = iio_dev_get_devdata(indio_dev);
117	int ret;
118	struct spi_transfer xfers[] = {
119	{
120	.tx_buf = st->tx,
121	.bits_per_word = 8,
122	.len = 2,
123	.cs_change = 1,
124	.delay_usecs = 30,
125	}, {
126	.rx_buf = st->rx,
127	.bits_per_word = 8,
128	.len = 2,
129	.cs_change = 1,
130	.delay_usecs = 30,
131	},
132	};
133
134	mutex_lock(&st->buf_lock);
135	st->tx[0] = ADIS16260_READ_REG(lower_reg_address);
136	st->tx[1] = 0;
137	st->tx[2] = 0;
138	st->tx[3] = 0;
139
140	spi_message_init(&msg);
141	spi_message_add_tail(&xfers[0], &msg);
142	spi_message_add_tail(&xfers[1], &msg);
143	ret = spi_sync(st->us, &msg);
144	if (ret) {
145	dev_err(&st->us->dev,
146	"problem when reading 16 bit register 0x%02X",
147	lower_reg_address);
148	goto error_ret;
149	}
150	*val = (st->rx[0] << 8) \| st->rx[1];
151
152	error_ret:
153	mutex_unlock(&st->buf_lock);
154	return ret;
155	}
156
157	static ssize_t adis16260_spi_read_signed(struct device *dev,
158	struct device_attribute *attr,
159	char *buf,
160	unsigned bits)
161	{
162	int ret;
163	s16 val = 0;
164	unsigned shift = 16 - bits;
165	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
166
167	ret = adis16260_spi_read_reg_16(dev, this_attr->address, (u16 *)&val);
168	if (ret)
169	return ret;
170
171	if (val & ADIS16260_ERROR_ACTIVE)
172	adis16260_check_status(dev);
173	val = ((s16)(val << shift) >> shift);
174	return sprintf(buf, "%d\n", val);
175	}
176
177	static ssize_t adis16260_read_12bit_unsigned(struct device *dev,
178	struct device_attribute *attr,
179	char *buf)
180	{
181	int ret;
182	u16 val = 0;
183	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
184
185	ret = adis16260_spi_read_reg_16(dev, this_attr->address, &val);
186	if (ret)
187	return ret;
188
189	if (val & ADIS16260_ERROR_ACTIVE)
190	adis16260_check_status(dev);
191
192	return sprintf(buf, "%u\n", val & 0x0FFF);
193	}
194
195	static ssize_t adis16260_read_12bit_signed(struct device *dev,
196	struct device_attribute *attr,
197	char *buf)
198	{
199	struct iio_dev *indio_dev = dev_get_drvdata(dev);
200	ssize_t ret;
201
202	/* Take the iio_dev status lock */
203	mutex_lock(&indio_dev->mlock);
204	ret = adis16260_spi_read_signed(dev, attr, buf, 12);
205	mutex_unlock(&indio_dev->mlock);
206
207	return ret;
208	}
209
210	static ssize_t adis16260_read_14bit_signed(struct device *dev,
211	struct device_attribute *attr,
212	char *buf)
213	{
214	struct iio_dev *indio_dev = dev_get_drvdata(dev);
215	ssize_t ret;
216
217	/* Take the iio_dev status lock */
218	mutex_lock(&indio_dev->mlock);
219	ret = adis16260_spi_read_signed(dev, attr, buf, 14);
220	mutex_unlock(&indio_dev->mlock);
221
222	return ret;
223	}
224
225	static ssize_t adis16260_write_16bit(struct device *dev,
226	struct device_attribute *attr,
227	const char *buf,
228	size_t len)
229	{
230	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
231	int ret;
232	long val;
233
234	ret = strict_strtol(buf, 10, &val);
235	if (ret)
236	goto error_ret;
237	ret = adis16260_spi_write_reg_16(dev, this_attr->address, val);
238
239	error_ret:
240	return ret ? ret : len;
241	}
242
243	static ssize_t adis16260_read_frequency(struct device *dev,
244	struct device_attribute *attr,
245	char *buf)
246	{
247	int ret, len = 0;
248	u16 t;
249	int sps;
250	ret = adis16260_spi_read_reg_16(dev,
251	ADIS16260_SMPL_PRD,
252	&t);
253	if (ret)
254	return ret;
255	sps = (t & ADIS16260_SMPL_PRD_TIME_BASE) ? 66 : 2048;
256	sps /= (t & ADIS16260_SMPL_PRD_DIV_MASK) + 1;
257	len = sprintf(buf, "%d SPS\n", sps);
258	return len;
259	}
260
261	static ssize_t adis16260_write_frequency(struct device *dev,
262	struct device_attribute *attr,
263	const char *buf,
264	size_t len)
265	{
266	struct iio_dev *indio_dev = dev_get_drvdata(dev);
267	struct adis16260_state *st = iio_dev_get_devdata(indio_dev);
268	long val;
269	int ret;
270	u8 t;
271
272	ret = strict_strtol(buf, 10, &val);
273	if (ret)
274	return ret;
275
276	mutex_lock(&indio_dev->mlock);
277
278	t = (2048 / val);
279	if (t > 0)
280	t--;
281	t &= ADIS16260_SMPL_PRD_DIV_MASK;
282	if ((t & ADIS16260_SMPL_PRD_DIV_MASK) >= 0x0A)
283	st->us->max_speed_hz = ADIS16260_SPI_SLOW;
284	else
285	st->us->max_speed_hz = ADIS16260_SPI_FAST;
286
287	ret = adis16260_spi_write_reg_8(dev,
288	ADIS16260_SMPL_PRD,
289	t);
290
291	mutex_unlock(&indio_dev->mlock);
292
293	return ret ? ret : len;
294	}
295
296	static int adis16260_reset(struct device *dev)
297	{
298	int ret;
299	ret = adis16260_spi_write_reg_8(dev,
300	ADIS16260_GLOB_CMD,
301	ADIS16260_GLOB_CMD_SW_RESET);
302	if (ret)
303	dev_err(dev, "problem resetting device");
304
305	return ret;
306	}
307
308	static ssize_t adis16260_write_reset(struct device *dev,
309	struct device_attribute *attr,
310	const char *buf, size_t len)
311	{
312	if (len < 1)
313	return -EINVAL;
314	switch (buf[0]) {
315	case '1':
316	case 'y':
317	case 'Y':
318	return adis16260_reset(dev);
319	}
320	return -EINVAL;
321	}
322
323	int adis16260_set_irq(struct device *dev, bool enable)
324	{
325	int ret;
326	u16 msc;
327	ret = adis16260_spi_read_reg_16(dev, ADIS16260_MSC_CTRL, &msc);
328	if (ret)
329	goto error_ret;
330
331	msc \|= ADIS16260_MSC_CTRL_DATA_RDY_POL_HIGH;
332	if (enable)
333	msc \|= ADIS16260_MSC_CTRL_DATA_RDY_EN;
334	else
335	msc &= ~ADIS16260_MSC_CTRL_DATA_RDY_EN;
336
337	ret = adis16260_spi_write_reg_16(dev, ADIS16260_MSC_CTRL, msc);
338	if (ret)
339	goto error_ret;
340
341	error_ret:
342	return ret;
343	}
344
345	/* Power down the device */
346	static int adis16260_stop_device(struct device *dev)
347	{
348	int ret;
349	u16 val = ADIS16260_SLP_CNT_POWER_OFF;
350
351	ret = adis16260_spi_write_reg_16(dev, ADIS16260_SLP_CNT, val);
352	if (ret)
353	dev_err(dev, "problem with turning device off: SLP_CNT");
354
355	return ret;
356	}
357
358	static int adis16260_self_test(struct device *dev)
359	{
360	int ret;
361	ret = adis16260_spi_write_reg_16(dev,
362	ADIS16260_MSC_CTRL,
363	ADIS16260_MSC_CTRL_MEM_TEST);
364	if (ret) {
365	dev_err(dev, "problem starting self test");
366	goto err_ret;
367	}
368
369	adis16260_check_status(dev);
370
371	err_ret:
372	return ret;
373	}
374
375	static int adis16260_check_status(struct device *dev)
376	{
377	u16 status;
378	int ret;
379
380	ret = adis16260_spi_read_reg_16(dev, ADIS16260_DIAG_STAT, &status);
381
382	if (ret < 0) {
383	dev_err(dev, "Reading status failed\n");
384	goto error_ret;
385	}
386	ret = status & 0x7F;
387	if (status & ADIS16260_DIAG_STAT_FLASH_CHK)
388	dev_err(dev, "Flash checksum error\n");
389	if (status & ADIS16260_DIAG_STAT_SELF_TEST)
390	dev_err(dev, "Self test error\n");
391	if (status & ADIS16260_DIAG_STAT_OVERFLOW)
392	dev_err(dev, "Sensor overrange\n");
393	if (status & ADIS16260_DIAG_STAT_SPI_FAIL)
394	dev_err(dev, "SPI failure\n");
395	if (status & ADIS16260_DIAG_STAT_FLASH_UPT)
396	dev_err(dev, "Flash update failed\n");
397	if (status & ADIS16260_DIAG_STAT_POWER_HIGH)
398	dev_err(dev, "Power supply above 5.25V\n");
399	if (status & ADIS16260_DIAG_STAT_POWER_LOW)
400	dev_err(dev, "Power supply below 4.75V\n");
401
402	error_ret:
403	return ret;
404	}
405
406	static int adis16260_initial_setup(struct adis16260_state *st)
407	{
408	int ret;
409	struct device *dev = &st->indio_dev->dev;
410
411	/* Disable IRQ */
412	ret = adis16260_set_irq(dev, false);
413	if (ret) {
414	dev_err(dev, "disable irq failed");
415	goto err_ret;
416	}
417
418	/* Do self test */
419	ret = adis16260_self_test(dev);
420	if (ret) {
421	dev_err(dev, "self test failure");
422	goto err_ret;
423	}
424
425	/* Read status register to check the result */
426	ret = adis16260_check_status(dev);
427	if (ret) {
428	adis16260_reset(dev);
429	dev_err(dev, "device not playing ball -> reset");
430	msleep(ADIS16260_STARTUP_DELAY);
431	ret = adis16260_check_status(dev);
432	if (ret) {
433	dev_err(dev, "giving up");
434	goto err_ret;
435	}
436	}
437
438	printk(KERN_INFO DRIVER_NAME ": at CS%d (irq %d)\n",
439	st->us->chip_select, st->us->irq);
440
441	err_ret:
442	return ret;
443	}
444
1755b0ae	445	static IIO_DEV_ATTR_IN_NAMED_RAW(0, supply,
089a4198 BS	446	adis16260_read_12bit_unsigned,
089a4198 BS	447	ADIS16260_SUPPLY_OUT);
1755b0ae	448	static IIO_CONST_ATTR_IN_NAMED_SCALE(0, supply, "0.0018315");
089a4198 BS	449
	450	static IIO_DEV_ATTR_GYRO(adis16260_read_14bit_signed,
	451	ADIS16260_GYRO_OUT);
4f64b801	452	static IIO_CONST_ATTR_GYRO_SCALE("0.00127862821");
51a0a5b0	453	static IIO_DEV_ATTR_GYRO_CALIBSCALE(S_IWUSR \| S_IRUGO,
089a4198 BS	454	adis16260_read_14bit_signed,
	455	adis16260_write_16bit,
	456	ADIS16260_GYRO_SCALE);
51a0a5b0	457	static IIO_DEV_ATTR_GYRO_CALIBBIAS(S_IWUSR \| S_IRUGO,
089a4198 BS	458	adis16260_read_12bit_signed,
	459	adis16260_write_16bit,
	460	ADIS16260_GYRO_OFF);
	461
	462	static IIO_DEV_ATTR_TEMP_RAW(adis16260_read_12bit_unsigned);
51a0a5b0 MS	463	static IIO_CONST_ATTR_TEMP_OFFSET("25");
51a0a5b0 MS	464	static IIO_CONST_ATTR_TEMP_SCALE("0.1453");
089a4198	465
1755b0ae	466	static IIO_DEV_ATTR_IN_RAW(1, adis16260_read_12bit_unsigned,
089a4198	467	ADIS16260_AUX_ADC);
1755b0ae	468	static IIO_CONST_ATTR(in1_scale, "0.0006105");
089a4198 BS	469
	470	static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR \| S_IRUGO,
	471	adis16260_read_frequency,
	472	adis16260_write_frequency);
	473	static IIO_DEV_ATTR_ANGL(adis16260_read_14bit_signed,
	474	ADIS16260_ANGL_OUT);
	475
	476	static IIO_DEVICE_ATTR(reset, S_IWUSR, NULL, adis16260_write_reset, 0);
	477
51a0a5b0	478	static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("256 2048");
089a4198	479
51a0a5b0	480	static IIO_CONST_ATTR_NAME("adis16260");
089a4198 BS	481
	482	static struct attribute *adis16260_event_attributes[] = {
	483	NULL
	484	};
	485
	486	static struct attribute_group adis16260_event_attribute_group = {
	487	.attrs = adis16260_event_attributes,
	488	};
	489
	490	static struct attribute *adis16260_attributes[] = {
1755b0ae JC	491	&iio_dev_attr_in0_supply_raw.dev_attr.attr,
1755b0ae JC	492	&iio_const_attr_in0_supply_scale.dev_attr.attr,
089a4198	493	&iio_dev_attr_gyro_raw.dev_attr.attr,
4f64b801	494	&iio_const_attr_gyro_scale.dev_attr.attr,
51a0a5b0 MS	495	&iio_dev_attr_gyro_calibscale.dev_attr.attr,
51a0a5b0 MS	496	&iio_dev_attr_gyro_calibbias.dev_attr.attr,
089a4198 BS	497	&iio_dev_attr_angl_raw.dev_attr.attr,
	498	&iio_dev_attr_temp_raw.dev_attr.attr,
	499	&iio_const_attr_temp_offset.dev_attr.attr,
	500	&iio_const_attr_temp_scale.dev_attr.attr,
1755b0ae JC	501	&iio_dev_attr_in1_raw.dev_attr.attr,
1755b0ae JC	502	&iio_const_attr_in1_scale.dev_attr.attr,
089a4198	503	&iio_dev_attr_sampling_frequency.dev_attr.attr,
51a0a5b0	504	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
089a4198 BS	505	&iio_dev_attr_reset.dev_attr.attr,
	506	&iio_const_attr_name.dev_attr.attr,
	507	NULL
	508	};
	509
	510	static const struct attribute_group adis16260_attribute_group = {
	511	.attrs = adis16260_attributes,
	512	};
	513
	514	static int __devinit adis16260_probe(struct spi_device *spi)
	515	{
	516	int ret, regdone = 0;
	517	struct adis16260_state st = kzalloc(sizeof st, GFP_KERNEL);
	518	if (!st) {
	519	ret = -ENOMEM;
	520	goto error_ret;
	521	}
	522	/* this is only used for removal purposes */
	523	spi_set_drvdata(spi, st);
	524
	525	/* Allocate the comms buffers */
	526	st->rx = kzalloc(sizeof(st->rx)ADIS16260_MAX_RX, GFP_KERNEL);
	527	if (st->rx == NULL) {
	528	ret = -ENOMEM;
	529	goto error_free_st;
	530	}
	531	st->tx = kzalloc(sizeof(st->tx)ADIS16260_MAX_TX, GFP_KERNEL);
	532	if (st->tx == NULL) {
	533	ret = -ENOMEM;
	534	goto error_free_rx;
	535	}
	536	st->us = spi;
	537	mutex_init(&st->buf_lock);
	538	/* setup the industrialio driver allocated elements */
	539	st->indio_dev = iio_allocate_device();
	540	if (st->indio_dev == NULL) {
	541	ret = -ENOMEM;
	542	goto error_free_tx;
	543	}
	544
	545	st->indio_dev->dev.parent = &spi->dev;
	546	st->indio_dev->num_interrupt_lines = 1;
	547	st->indio_dev->event_attrs = &adis16260_event_attribute_group;
	548	st->indio_dev->attrs = &adis16260_attribute_group;
	549	st->indio_dev->dev_data = (void *)(st);
	550	st->indio_dev->driver_module = THIS_MODULE;
	551	st->indio_dev->modes = INDIO_DIRECT_MODE;
	552
	553	ret = adis16260_configure_ring(st->indio_dev);
	554	if (ret)
	555	goto error_free_dev;
	556
	557	ret = iio_device_register(st->indio_dev);
	558	if (ret)
	559	goto error_unreg_ring_funcs;
	560	regdone = 1;
2662051e	561	ret = iio_ring_buffer_register(st->indio_dev->ring, 0);
089a4198 BS	562	if (ret) {
	563	printk(KERN_ERR "failed to initialize the ring\n");
	564	goto error_unreg_ring_funcs;
	565	}
	566
	567	if (spi->irq) {
	568	ret = iio_register_interrupt_line(spi->irq,
	569	st->indio_dev,
	570	0,
	571	IRQF_TRIGGER_RISING,
	572	"adis16260");
	573	if (ret)
	574	goto error_uninitialize_ring;
	575
	576	ret = adis16260_probe_trigger(st->indio_dev);
	577	if (ret)
	578	goto error_unregister_line;
	579	}
	580
	581	/* Get the device into a sane initial state */
	582	ret = adis16260_initial_setup(st);
	583	if (ret)
	584	goto error_remove_trigger;
	585	return 0;
	586
	587	error_remove_trigger:
	588	adis16260_remove_trigger(st->indio_dev);
	589	error_unregister_line:
	590	if (spi->irq)
	591	iio_unregister_interrupt_line(st->indio_dev, 0);
	592	error_uninitialize_ring:
2662051e	593	iio_ring_buffer_unregister(st->indio_dev->ring);
089a4198 BS	594	error_unreg_ring_funcs:
	595	adis16260_unconfigure_ring(st->indio_dev);
	596	error_free_dev:
	597	if (regdone)
	598	iio_device_unregister(st->indio_dev);
	599	else
	600	iio_free_device(st->indio_dev);
	601	error_free_tx:
	602	kfree(st->tx);
	603	error_free_rx:
	604	kfree(st->rx);
	605	error_free_st:
	606	kfree(st);
	607	error_ret:
	608	return ret;
	609	}
	610
	611	static int adis16260_remove(struct spi_device *spi)
	612	{
	613	int ret;
	614	struct adis16260_state *st = spi_get_drvdata(spi);
	615	struct iio_dev *indio_dev = st->indio_dev;
	616
	617	ret = adis16260_stop_device(&(indio_dev->dev));
	618	if (ret)
	619	goto err_ret;
	620
	621	flush_scheduled_work();
	622
	623	adis16260_remove_trigger(indio_dev);
	624	if (spi->irq)
	625	iio_unregister_interrupt_line(indio_dev, 0);
	626
2662051e	627	iio_ring_buffer_unregister(st->indio_dev->ring);
089a4198 BS	628	iio_device_unregister(indio_dev);
	629	adis16260_unconfigure_ring(indio_dev);
	630	kfree(st->tx);
	631	kfree(st->rx);
	632	kfree(st);
	633
089a4198 BS	634	err_ret:
	635	return ret;
	636	}
	637
	638	static struct spi_driver adis16260_driver = {
	639	.driver = {
	640	.name = "adis16260",
	641	.owner = THIS_MODULE,
	642	},
	643	.probe = adis16260_probe,
	644	.remove = __devexit_p(adis16260_remove),
	645	};
	646
	647	static __init int adis16260_init(void)
	648	{
	649	return spi_register_driver(&adis16260_driver);
	650	}
	651	module_init(adis16260_init);
	652
	653	static __exit void adis16260_exit(void)
	654	{
	655	spi_unregister_driver(&adis16260_driver);
	656	}
	657	module_exit(adis16260_exit);
	658
	659	MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
	660	MODULE_DESCRIPTION("Analog Devices ADIS16260/5 Digital Gyroscope Sensor");
	661	MODULE_LICENSE("GPL v2");