[mirror_ubuntu-zesty-kernel.git] / drivers / iio / accel / stk8312.c

/**
 * Sensortek STK8312 3-Axis Accelerometer
 *
 * Copyright (c) 2015, Intel Corporation.
 *
 * This file is subject to the terms and conditions of version 2 of
 * the GNU General Public License. See the file COPYING in the main
 * directory of this archive for more details.
 *
 * IIO driver for STK8312; 7-bit I2C address: 0x3D.
 */

#include <linux/acpi.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/iio/buffer.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/trigger.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/trigger_consumer.h>

#define STK8312_REG_XOUT		0x00
#define STK8312_REG_YOUT		0x01
#define STK8312_REG_ZOUT		0x02
#define STK8312_REG_INTSU		0x06
#define STK8312_REG_MODE		0x07
#define STK8312_REG_SR			0x08
#define STK8312_REG_STH			0x13
#define STK8312_REG_RESET		0x20
#define STK8312_REG_AFECTRL		0x24
#define STK8312_REG_OTPADDR		0x3D
#define STK8312_REG_OTPDATA		0x3E
#define STK8312_REG_OTPCTRL		0x3F

#define STK8312_MODE_ACTIVE		BIT(0)
#define STK8312_MODE_STANDBY		0x00
#define STK8312_MODE_INT_AH_PP		0xC0	/* active-high, push-pull */
#define STK8312_DREADY_BIT		BIT(4)
#define STK8312_RNG_6G			1
#define STK8312_RNG_SHIFT		6
#define STK8312_RNG_MASK		GENMASK(7, 6)
#define STK8312_SR_MASK			GENMASK(2, 0)
#define STK8312_SR_400HZ_IDX		0
#define STK8312_ALL_CHANNEL_MASK	GENMASK(2, 0)
#define STK8312_ALL_CHANNEL_SIZE	3

#define STK8312_DRIVER_NAME		"stk8312"
#define STK8312_IRQ_NAME		"stk8312_event"

/*
 * The accelerometer has two measurement ranges:
 *
 * -6g - +6g (8-bit, signed)
 * -16g - +16g (8-bit, signed)
 *
 * scale1 = (6 + 6) * 9.81 / (2^8 - 1)     = 0.4616
 * scale2 = (16 + 16) * 9.81 / (2^8 - 1)   = 1.2311
 */
#define STK8312_SCALE_AVAIL		"0.4616 1.2311"

static const int stk8312_scale_table[][2] = {
	{0, 461600}, {1, 231100}
};

static const struct {
	int val;
	int val2;
} stk8312_samp_freq_table[] = {
	{400, 0}, {200, 0}, {100, 0}, {50, 0}, {25, 0},
	{12, 500000}, {6, 250000}, {3, 125000}
};

#define STK8312_ACCEL_CHANNEL(index, reg, axis) {			\
	.type = IIO_ACCEL,						\
	.address = reg,							\
	.modified = 1,							\
	.channel2 = IIO_MOD_##axis,					\
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
				    BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
	.scan_index = index,						\
	.scan_type = {							\
		.sign = 's',						\
		.realbits = 8,						\
		.storagebits = 8,					\
		.endianness = IIO_CPU,					\
	},								\
}

static const struct iio_chan_spec stk8312_channels[] = {
	STK8312_ACCEL_CHANNEL(0, STK8312_REG_XOUT, X),
	STK8312_ACCEL_CHANNEL(1, STK8312_REG_YOUT, Y),
	STK8312_ACCEL_CHANNEL(2, STK8312_REG_ZOUT, Z),
	IIO_CHAN_SOFT_TIMESTAMP(3),
};

struct stk8312_data {
	struct i2c_client *client;
	struct mutex lock;
	u8 range;
	u8 sample_rate_idx;
	u8 mode;
	struct iio_trigger *dready_trig;
	bool dready_trigger_on;
	s8 buffer[16]; /* 3x8-bit channels + 5x8 padding + 64-bit timestamp */
};

static IIO_CONST_ATTR(in_accel_scale_available, STK8312_SCALE_AVAIL);

static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("3.125 6.25 12.5 25 50 100 200 400");

static struct attribute *stk8312_attributes[] = {
	&iio_const_attr_in_accel_scale_available.dev_attr.attr,
	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
	NULL,
};

static const struct attribute_group stk8312_attribute_group = {
	.attrs = stk8312_attributes
};

static int stk8312_otp_init(struct stk8312_data *data)
{
	int ret;
	int count = 10;
	struct i2c_client *client = data->client;

	ret = i2c_smbus_write_byte_data(client, STK8312_REG_OTPADDR, 0x70);
	if (ret < 0)
		goto exit_err;
	ret = i2c_smbus_write_byte_data(client, STK8312_REG_OTPCTRL, 0x02);
	if (ret < 0)
		goto exit_err;

	do {
		usleep_range(1000, 5000);
		ret = i2c_smbus_read_byte_data(client, STK8312_REG_OTPCTRL);
		if (ret < 0)
			goto exit_err;
		count--;
	} while (!(ret & BIT(7)) && count > 0);

	if (count == 0) {
		ret = -ETIMEDOUT;
		goto exit_err;
	}

	ret = i2c_smbus_read_byte_data(client, STK8312_REG_OTPDATA);
	if (ret == 0)
		ret = -EINVAL;
	if (ret < 0)
		goto exit_err;

	ret = i2c_smbus_write_byte_data(data->client, STK8312_REG_AFECTRL, ret);
	if (ret < 0)
		goto exit_err;
	msleep(150);

	return 0;

exit_err:
	dev_err(&client->dev, "failed to initialize sensor\n");
	return ret;
}

static int stk8312_set_mode(struct stk8312_data *data, u8 mode)
{
	int ret;
	struct i2c_client *client = data->client;

	if (mode == data->mode)
		return 0;

	ret = i2c_smbus_write_byte_data(client, STK8312_REG_MODE, mode);
	if (ret < 0) {
		dev_err(&client->dev, "failed to change sensor mode\n");
		return ret;
	}

	data->mode = mode;
	if (mode & STK8312_MODE_ACTIVE) {
		/* Need to run OTP sequence before entering active mode */
		usleep_range(1000, 5000);
		ret = stk8312_otp_init(data);
	}

	return ret;
}

static int stk8312_set_interrupts(struct stk8312_data *data, u8 int_mask)
{
	int ret;
	u8 mode;
	struct i2c_client *client = data->client;

	mode = data->mode;
	/* We need to go in standby mode to modify registers */
	ret = stk8312_set_mode(data, STK8312_MODE_STANDBY);
	if (ret < 0)
		return ret;

	ret = i2c_smbus_write_byte_data(client, STK8312_REG_INTSU, int_mask);
	if (ret < 0) {
		dev_err(&client->dev, "failed to set interrupts\n");
		stk8312_set_mode(data, mode);
		return ret;
	}

	return stk8312_set_mode(data, mode);
}

static int stk8312_data_rdy_trigger_set_state(struct iio_trigger *trig,
					      bool state)
{
	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
	struct stk8312_data *data = iio_priv(indio_dev);
	int ret;

	if (state)
		ret = stk8312_set_interrupts(data, STK8312_DREADY_BIT);
	else
		ret = stk8312_set_interrupts(data, 0x00);

	if (ret < 0) {
		dev_err(&data->client->dev, "failed to set trigger state\n");
		return ret;
	}

	data->dready_trigger_on = state;

	return 0;
}

static const struct iio_trigger_ops stk8312_trigger_ops = {
	.set_trigger_state = stk8312_data_rdy_trigger_set_state,
	.owner = THIS_MODULE,
};

static int stk8312_set_sample_rate(struct stk8312_data *data, u8 rate)
{
	int ret;
	u8 masked_reg;
	u8 mode;
	struct i2c_client *client = data->client;

	if (rate == data->sample_rate_idx)
		return 0;

	mode = data->mode;
	/* We need to go in standby mode to modify registers */
	ret = stk8312_set_mode(data, STK8312_MODE_STANDBY);
	if (ret < 0)
		return ret;

	ret = i2c_smbus_read_byte_data(client, STK8312_REG_SR);
	if (ret < 0)
		goto err_activate;

	masked_reg = (ret & (~STK8312_SR_MASK)) | rate;

	ret = i2c_smbus_write_byte_data(client, STK8312_REG_SR, masked_reg);
	if (ret < 0)
		goto err_activate;

	data->sample_rate_idx = rate;

	return stk8312_set_mode(data, mode);

err_activate:
	dev_err(&client->dev, "failed to set sampling rate\n");
	stk8312_set_mode(data, mode);

	return ret;
}

static int stk8312_set_range(struct stk8312_data *data, u8 range)
{
	int ret;
	u8 masked_reg;
	u8 mode;
	struct i2c_client *client = data->client;

	if (range != 1 && range != 2)
		return -EINVAL;
	else if (range == data->range)
		return 0;

	mode = data->mode;
	/* We need to go in standby mode to modify registers */
	ret = stk8312_set_mode(data, STK8312_MODE_STANDBY);
	if (ret < 0)
		return ret;

	ret = i2c_smbus_read_byte_data(client, STK8312_REG_STH);
	if (ret < 0)
		goto err_activate;

	masked_reg = ret & (~STK8312_RNG_MASK);
	masked_reg |= range << STK8312_RNG_SHIFT;

	ret = i2c_smbus_write_byte_data(client, STK8312_REG_STH, masked_reg);
	if (ret < 0)
		goto err_activate;

	data->range = range;

	return stk8312_set_mode(data, mode);

err_activate:
	dev_err(&client->dev, "failed to change sensor range\n");
	stk8312_set_mode(data, mode);

	return ret;
}

static int stk8312_read_accel(struct stk8312_data *data, u8 address)
{
	int ret;
	struct i2c_client *client = data->client;

	if (address > 2)
		return -EINVAL;

	ret = i2c_smbus_read_byte_data(client, address);
	if (ret < 0)
		dev_err(&client->dev, "register read failed\n");

	return ret;
}

static int stk8312_read_raw(struct iio_dev *indio_dev,
			    struct iio_chan_spec const *chan,
			    int *val, int *val2, long mask)
{
	struct stk8312_data *data = iio_priv(indio_dev);
	int ret;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		if (iio_buffer_enabled(indio_dev))
			return -EBUSY;
		mutex_lock(&data->lock);
		ret = stk8312_set_mode(data, data->mode | STK8312_MODE_ACTIVE);
		if (ret < 0) {
			mutex_unlock(&data->lock);
			return ret;
		}
		ret = stk8312_read_accel(data, chan->address);
		if (ret < 0) {
			stk8312_set_mode(data,
					 data->mode & (~STK8312_MODE_ACTIVE));
			mutex_unlock(&data->lock);
			return ret;
		}
		*val = sign_extend32(ret, 7);
		ret = stk8312_set_mode(data,
				       data->mode & (~STK8312_MODE_ACTIVE));
		mutex_unlock(&data->lock);
		if (ret < 0)
			return ret;
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_SCALE:
		*val = stk8312_scale_table[data->range - 1][0];
		*val2 = stk8312_scale_table[data->range - 1][1];
		return IIO_VAL_INT_PLUS_MICRO;
	case IIO_CHAN_INFO_SAMP_FREQ:
		*val = stk8312_samp_freq_table[data->sample_rate_idx].val;
		*val2 = stk8312_samp_freq_table[data->sample_rate_idx].val2;
		return IIO_VAL_INT_PLUS_MICRO;
	}

	return -EINVAL;
}

static int stk8312_write_raw(struct iio_dev *indio_dev,
			     struct iio_chan_spec const *chan,
			     int val, int val2, long mask)
{
	int i;
	int index = -1;
	int ret;
	struct stk8312_data *data = iio_priv(indio_dev);

	switch (mask) {
	case IIO_CHAN_INFO_SCALE:
		for (i = 0; i < ARRAY_SIZE(stk8312_scale_table); i++)
			if (val == stk8312_scale_table[i][0] &&
			    val2 == stk8312_scale_table[i][1]) {
				index = i + 1;
				break;
			}
		if (index < 0)
			return -EINVAL;

		mutex_lock(&data->lock);
		ret = stk8312_set_range(data, index);
		mutex_unlock(&data->lock);

		return ret;
	case IIO_CHAN_INFO_SAMP_FREQ:
		for (i = 0; i < ARRAY_SIZE(stk8312_samp_freq_table); i++)
			if (val == stk8312_samp_freq_table[i].val &&
			    val2 == stk8312_samp_freq_table[i].val2) {
				index = i;
				break;
			}
		if (index < 0)
			return -EINVAL;
		mutex_lock(&data->lock);
		ret = stk8312_set_sample_rate(data, index);
		mutex_unlock(&data->lock);

		return ret;
	}

	return -EINVAL;
}

static const struct iio_info stk8312_info = {
	.driver_module		= THIS_MODULE,
	.read_raw		= stk8312_read_raw,
	.write_raw		= stk8312_write_raw,
	.attrs			= &stk8312_attribute_group,
};

static irqreturn_t stk8312_trigger_handler(int irq, void *p)
{
	struct iio_poll_func *pf = p;
	struct iio_dev *indio_dev = pf->indio_dev;
	struct stk8312_data *data = iio_priv(indio_dev);
	int bit, ret, i = 0;

	mutex_lock(&data->lock);
	/*
	 * Do a bulk read if all channels are requested,
	 * from 0x00 (XOUT) to 0x02 (ZOUT)
	 */
	if (*(indio_dev->active_scan_mask) == STK8312_ALL_CHANNEL_MASK) {
		ret = i2c_smbus_read_i2c_block_data(data->client,
						    STK8312_REG_XOUT,
						    STK8312_ALL_CHANNEL_SIZE,
						    data->buffer);
		if (ret < STK8312_ALL_CHANNEL_SIZE) {
			dev_err(&data->client->dev, "register read failed\n");
			mutex_unlock(&data->lock);
			goto err;
		}
	} else {
		for_each_set_bit(bit, indio_dev->active_scan_mask,
				 indio_dev->masklength) {
			ret = stk8312_read_accel(data, bit);
			if (ret < 0) {
				mutex_unlock(&data->lock);
				goto err;
			}
			data->buffer[i++] = ret;
		}
	}
	mutex_unlock(&data->lock);

	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
					   pf->timestamp);
err:
	iio_trigger_notify_done(indio_dev->trig);

	return IRQ_HANDLED;
}

static irqreturn_t stk8312_data_rdy_trig_poll(int irq, void *private)
{
	struct iio_dev *indio_dev = private;
	struct stk8312_data *data = iio_priv(indio_dev);

	if (data->dready_trigger_on)
		iio_trigger_poll(data->dready_trig);

	return IRQ_HANDLED;
}

static int stk8312_buffer_preenable(struct iio_dev *indio_dev)
{
	struct stk8312_data *data = iio_priv(indio_dev);

	return stk8312_set_mode(data, data->mode | STK8312_MODE_ACTIVE);
}

static int stk8312_buffer_postdisable(struct iio_dev *indio_dev)
{
	struct stk8312_data *data = iio_priv(indio_dev);

	return stk8312_set_mode(data, data->mode & (~STK8312_MODE_ACTIVE));
}

static const struct iio_buffer_setup_ops stk8312_buffer_setup_ops = {
	.preenable   = stk8312_buffer_preenable,
	.postenable  = iio_triggered_buffer_postenable,
	.predisable  = iio_triggered_buffer_predisable,
	.postdisable = stk8312_buffer_postdisable,
};

static int stk8312_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	int ret;
	struct iio_dev *indio_dev;
	struct stk8312_data *data;

	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	if (!indio_dev) {
		dev_err(&client->dev, "iio allocation failed!\n");
		return -ENOMEM;
	}

	data = iio_priv(indio_dev);
	data->client = client;
	i2c_set_clientdata(client, indio_dev);
	mutex_init(&data->lock);

	indio_dev->dev.parent = &client->dev;
	indio_dev->info = &stk8312_info;
	indio_dev->name = STK8312_DRIVER_NAME;
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->channels = stk8312_channels;
	indio_dev->num_channels = ARRAY_SIZE(stk8312_channels);

	/* A software reset is recommended at power-on */
	ret = i2c_smbus_write_byte_data(data->client, STK8312_REG_RESET, 0x00);
	if (ret < 0) {
		dev_err(&client->dev, "failed to reset sensor\n");
		return ret;
	}
	data->sample_rate_idx = STK8312_SR_400HZ_IDX;
	ret = stk8312_set_range(data, STK8312_RNG_6G);
	if (ret < 0)
		return ret;

	ret = stk8312_set_mode(data,
			       STK8312_MODE_INT_AH_PP | STK8312_MODE_ACTIVE);
	if (ret < 0)
		return ret;

	if (client->irq > 0) {
		ret = devm_request_threaded_irq(&client->dev, client->irq,
						stk8312_data_rdy_trig_poll,
						NULL,
						IRQF_TRIGGER_RISING |
						IRQF_ONESHOT,
						STK8312_IRQ_NAME,
						indio_dev);
		if (ret < 0) {
			dev_err(&client->dev, "request irq %d failed\n",
				client->irq);
			goto err_power_off;
		}

		data->dready_trig = devm_iio_trigger_alloc(&client->dev,
							   "%s-dev%d",
							   indio_dev->name,
							   indio_dev->id);
		if (!data->dready_trig) {
			ret = -ENOMEM;
			goto err_power_off;
		}

		data->dready_trig->dev.parent = &client->dev;
		data->dready_trig->ops = &stk8312_trigger_ops;
		iio_trigger_set_drvdata(data->dready_trig, indio_dev);
		ret = iio_trigger_register(data->dready_trig);
		if (ret) {
			dev_err(&client->dev, "iio trigger register failed\n");
			goto err_power_off;
		}
	}

	ret = iio_triggered_buffer_setup(indio_dev,
					 iio_pollfunc_store_time,
					 stk8312_trigger_handler,
					 &stk8312_buffer_setup_ops);
	if (ret < 0) {
		dev_err(&client->dev, "iio triggered buffer setup failed\n");
		goto err_trigger_unregister;
	}

	ret = iio_device_register(indio_dev);
	if (ret < 0) {
		dev_err(&client->dev, "device_register failed\n");
		goto err_buffer_cleanup;
	}

	return 0;

err_buffer_cleanup:
	iio_triggered_buffer_cleanup(indio_dev);
err_trigger_unregister:
	if (data->dready_trig)
		iio_trigger_unregister(data->dready_trig);
err_power_off:
	stk8312_set_mode(data, STK8312_MODE_STANDBY);
	return ret;
}

static int stk8312_remove(struct i2c_client *client)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(client);
	struct stk8312_data *data = iio_priv(indio_dev);

	iio_device_unregister(indio_dev);
	iio_triggered_buffer_cleanup(indio_dev);

	if (data->dready_trig)
		iio_trigger_unregister(data->dready_trig);

	return stk8312_set_mode(data, STK8312_MODE_STANDBY);
}

#ifdef CONFIG_PM_SLEEP
static int stk8312_suspend(struct device *dev)
{
	struct stk8312_data *data;

	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));

	return stk8312_set_mode(data, data->mode & (~STK8312_MODE_ACTIVE));
}

static int stk8312_resume(struct device *dev)
{
	struct stk8312_data *data;

	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));

	return stk8312_set_mode(data, data->mode | STK8312_MODE_ACTIVE);
}

static SIMPLE_DEV_PM_OPS(stk8312_pm_ops, stk8312_suspend, stk8312_resume);

#define STK8312_PM_OPS (&stk8312_pm_ops)
#else
#define STK8312_PM_OPS NULL
#endif

static const struct i2c_device_id stk8312_i2c_id[] = {
	{"STK8312", 0},
	{}
};
MODULE_DEVICE_TABLE(i2c, stk8312_i2c_id);

static const struct acpi_device_id stk8312_acpi_id[] = {
	{"STK8312", 0},
	{}
};

MODULE_DEVICE_TABLE(acpi, stk8312_acpi_id);

static struct i2c_driver stk8312_driver = {
	.driver = {
		.name = STK8312_DRIVER_NAME,
		.pm = STK8312_PM_OPS,
		.acpi_match_table = ACPI_PTR(stk8312_acpi_id),
	},
	.probe =            stk8312_probe,
	.remove =           stk8312_remove,
	.id_table =         stk8312_i2c_id,
};

module_i2c_driver(stk8312_driver);

MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
MODULE_DESCRIPTION("STK8312 3-Axis Accelerometer driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
90bad33a TB	1	/**
	2	* Sensortek STK8312 3-Axis Accelerometer
	3	*
	4	* Copyright (c) 2015, Intel Corporation.
	5	*
	6	* This file is subject to the terms and conditions of version 2 of
	7	* the GNU General Public License. See the file COPYING in the main
	8	* directory of this archive for more details.
	9	*
	10	* IIO driver for STK8312; 7-bit I2C address: 0x3D.
	11	*/
	12
	13	#include <linux/acpi.h>
	14	#include <linux/i2c.h>
95c12bba	15	#include <linux/interrupt.h>
90bad33a TB	16	#include <linux/kernel.h>
	17	#include <linux/module.h>
	18	#include <linux/delay.h>
95c12bba	19	#include <linux/iio/buffer.h>
90bad33a TB	20	#include <linux/iio/iio.h>
90bad33a TB	21	#include <linux/iio/sysfs.h>
95c12bba TB	22	#include <linux/iio/trigger.h>
	23	#include <linux/iio/triggered_buffer.h>
	24	#include <linux/iio/trigger_consumer.h>
90bad33a TB	25
	26	#define STK8312_REG_XOUT 0x00
	27	#define STK8312_REG_YOUT 0x01
	28	#define STK8312_REG_ZOUT 0x02
95c12bba	29	#define STK8312_REG_INTSU 0x06
90bad33a	30	#define STK8312_REG_MODE 0x07
5e913d27	31	#define STK8312_REG_SR 0x08
90bad33a TB	32	#define STK8312_REG_STH 0x13
	33	#define STK8312_REG_RESET 0x20
	34	#define STK8312_REG_AFECTRL 0x24
	35	#define STK8312_REG_OTPADDR 0x3D
	36	#define STK8312_REG_OTPDATA 0x3E
	37	#define STK8312_REG_OTPCTRL 0x3F
	38
03ecd50c	39	#define STK8312_MODE_ACTIVE BIT(0)
95c12bba	40	#define STK8312_MODE_STANDBY 0x00
03ecd50c HK	41	#define STK8312_MODE_INT_AH_PP 0xC0 /* active-high, push-pull */
	42	#define STK8312_DREADY_BIT BIT(4)
	43	#define STK8312_RNG_6G 1
90bad33a	44	#define STK8312_RNG_SHIFT 6
03ecd50c HK	45	#define STK8312_RNG_MASK GENMASK(7, 6)
	46	#define STK8312_SR_MASK GENMASK(2, 0)
	47	#define STK8312_SR_400HZ_IDX 0
	48	#define STK8312_ALL_CHANNEL_MASK GENMASK(2, 0)
95c12bba	49	#define STK8312_ALL_CHANNEL_SIZE 3
90bad33a TB	50
90bad33a TB	51	#define STK8312_DRIVER_NAME "stk8312"
95c12bba	52	#define STK8312_IRQ_NAME "stk8312_event"
90bad33a TB	53
	54	/*
	55	* The accelerometer has two measurement ranges:
	56	*
	57	* -6g - +6g (8-bit, signed)
	58	* -16g - +16g (8-bit, signed)
	59	*
	60	* scale1 = (6 + 6) * 9.81 / (2^8 - 1) = 0.4616
	61	* scale2 = (16 + 16) * 9.81 / (2^8 - 1) = 1.2311
	62	*/
	63	#define STK8312_SCALE_AVAIL "0.4616 1.2311"
	64
	65	static const int stk8312_scale_table[][2] = {
	66	{0, 461600}, {1, 231100}
	67	};
	68
5e913d27	69	static const struct {
7d73e02c HK	70	int val;
7d73e02c HK	71	int val2;
5e913d27 TB	72	} stk8312_samp_freq_table[] = {
	73	{400, 0}, {200, 0}, {100, 0}, {50, 0}, {25, 0},
	74	{12, 500000}, {6, 250000}, {3, 125000}
	75	};
	76
	77	#define STK8312_ACCEL_CHANNEL(index, reg, axis) { \
	78	.type = IIO_ACCEL, \
	79	.address = reg, \
	80	.modified = 1, \
	81	.channel2 = IIO_MOD_##axis, \
	82	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
	83	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \| \
	84	BIT(IIO_CHAN_INFO_SAMP_FREQ), \
	85	.scan_index = index, \
	86	.scan_type = { \
	87	.sign = 's', \
	88	.realbits = 8, \
	89	.storagebits = 8, \
	90	.endianness = IIO_CPU, \
	91	}, \
90bad33a TB	92	}
	93
	94	static const struct iio_chan_spec stk8312_channels[] = {
95c12bba TB	95	STK8312_ACCEL_CHANNEL(0, STK8312_REG_XOUT, X),
	96	STK8312_ACCEL_CHANNEL(1, STK8312_REG_YOUT, Y),
	97	STK8312_ACCEL_CHANNEL(2, STK8312_REG_ZOUT, Z),
	98	IIO_CHAN_SOFT_TIMESTAMP(3),
90bad33a TB	99	};
	100
	101	struct stk8312_data {
	102	struct i2c_client *client;
	103	struct mutex lock;
7d73e02c	104	u8 range;
5e913d27	105	u8 sample_rate_idx;
90bad33a	106	u8 mode;
95c12bba TB	107	struct iio_trigger *dready_trig;
	108	bool dready_trigger_on;
	109	s8 buffer[16]; /* 3x8-bit channels + 5x8 padding + 64-bit timestamp */
90bad33a TB	110	};
	111
	112	static IIO_CONST_ATTR(in_accel_scale_available, STK8312_SCALE_AVAIL);
	113
5e913d27 TB	114	static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("3.125 6.25 12.5 25 50 100 200 400");
5e913d27 TB	115
90bad33a TB	116	static struct attribute *stk8312_attributes[] = {
90bad33a TB	117	&iio_const_attr_in_accel_scale_available.dev_attr.attr,
5e913d27	118	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
90bad33a TB	119	NULL,
	120	};
	121
	122	static const struct attribute_group stk8312_attribute_group = {
	123	.attrs = stk8312_attributes
	124	};
	125
	126	static int stk8312_otp_init(struct stk8312_data *data)
	127	{
	128	int ret;
	129	int count = 10;
	130	struct i2c_client *client = data->client;
	131
	132	ret = i2c_smbus_write_byte_data(client, STK8312_REG_OTPADDR, 0x70);
	133	if (ret < 0)
	134	goto exit_err;
	135	ret = i2c_smbus_write_byte_data(client, STK8312_REG_OTPCTRL, 0x02);
	136	if (ret < 0)
	137	goto exit_err;
	138
	139	do {
	140	usleep_range(1000, 5000);
	141	ret = i2c_smbus_read_byte_data(client, STK8312_REG_OTPCTRL);
	142	if (ret < 0)
	143	goto exit_err;
	144	count--;
03ecd50c	145	} while (!(ret & BIT(7)) && count > 0);
90bad33a	146
18422bb3 HK	147	if (count == 0) {
18422bb3 HK	148	ret = -ETIMEDOUT;
90bad33a	149	goto exit_err;
18422bb3	150	}
90bad33a TB	151
90bad33a TB	152	ret = i2c_smbus_read_byte_data(client, STK8312_REG_OTPDATA);
b41e63cf HK	153	if (ret == 0)
b41e63cf HK	154	ret = -EINVAL;
90bad33a TB	155	if (ret < 0)
	156	goto exit_err;
	157
dca5d284	158	ret = i2c_smbus_write_byte_data(data->client, STK8312_REG_AFECTRL, ret);
90bad33a TB	159	if (ret < 0)
	160	goto exit_err;
	161	msleep(150);
	162
18422bb3	163	return 0;
90bad33a TB	164
	165	exit_err:
	166	dev_err(&client->dev, "failed to initialize sensor\n");
	167	return ret;
	168	}
	169
	170	static int stk8312_set_mode(struct stk8312_data *data, u8 mode)
	171	{
	172	int ret;
90bad33a TB	173	struct i2c_client *client = data->client;
90bad33a TB	174
95c12bba	175	if (mode == data->mode)
90bad33a TB	176	return 0;
90bad33a TB	177
95c12bba	178	ret = i2c_smbus_write_byte_data(client, STK8312_REG_MODE, mode);
90bad33a TB	179	if (ret < 0) {
	180	dev_err(&client->dev, "failed to change sensor mode\n");
	181	return ret;
	182	}
	183
	184	data->mode = mode;
95c12bba	185	if (mode & STK8312_MODE_ACTIVE) {
90bad33a TB	186	/* Need to run OTP sequence before entering active mode */
	187	usleep_range(1000, 5000);
	188	ret = stk8312_otp_init(data);
	189	}
	190
	191	return ret;
	192	}
	193
95c12bba TB	194	static int stk8312_set_interrupts(struct stk8312_data *data, u8 int_mask)
	195	{
	196	int ret;
	197	u8 mode;
	198	struct i2c_client *client = data->client;
	199
	200	mode = data->mode;
	201	/* We need to go in standby mode to modify registers */
	202	ret = stk8312_set_mode(data, STK8312_MODE_STANDBY);
	203	if (ret < 0)
	204	return ret;
	205
	206	ret = i2c_smbus_write_byte_data(client, STK8312_REG_INTSU, int_mask);
18422bb3	207	if (ret < 0) {
95c12bba	208	dev_err(&client->dev, "failed to set interrupts\n");
18422bb3 HK	209	stk8312_set_mode(data, mode);
	210	return ret;
	211	}
95c12bba TB	212
	213	return stk8312_set_mode(data, mode);
	214	}
	215
	216	static int stk8312_data_rdy_trigger_set_state(struct iio_trigger *trig,
	217	bool state)
	218	{
	219	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
	220	struct stk8312_data *data = iio_priv(indio_dev);
	221	int ret;
	222
	223	if (state)
	224	ret = stk8312_set_interrupts(data, STK8312_DREADY_BIT);
	225	else
	226	ret = stk8312_set_interrupts(data, 0x00);
	227
	228	if (ret < 0) {
	229	dev_err(&data->client->dev, "failed to set trigger state\n");
	230	return ret;
	231	}
	232
	233	data->dready_trigger_on = state;
	234
18422bb3	235	return 0;
95c12bba TB	236	}
	237
	238	static const struct iio_trigger_ops stk8312_trigger_ops = {
	239	.set_trigger_state = stk8312_data_rdy_trigger_set_state,
	240	.owner = THIS_MODULE,
	241	};
	242
7d73e02c	243	static int stk8312_set_sample_rate(struct stk8312_data *data, u8 rate)
5e913d27 TB	244	{
	245	int ret;
	246	u8 masked_reg;
	247	u8 mode;
	248	struct i2c_client *client = data->client;
	249
	250	if (rate == data->sample_rate_idx)
	251	return 0;
	252
	253	mode = data->mode;
	254	/* We need to go in standby mode to modify registers */
	255	ret = stk8312_set_mode(data, STK8312_MODE_STANDBY);
	256	if (ret < 0)
	257	return ret;
	258
	259	ret = i2c_smbus_read_byte_data(client, STK8312_REG_SR);
18422bb3 HK	260	if (ret < 0)
18422bb3 HK	261	goto err_activate;
5e913d27 TB	262
	263	masked_reg = (ret & (~STK8312_SR_MASK)) \| rate;
	264
	265	ret = i2c_smbus_write_byte_data(client, STK8312_REG_SR, masked_reg);
	266	if (ret < 0)
18422bb3 HK	267	goto err_activate;
	268
	269	data->sample_rate_idx = rate;
5e913d27 TB	270
5e913d27 TB	271	return stk8312_set_mode(data, mode);
18422bb3 HK	272
	273	err_activate:
	274	dev_err(&client->dev, "failed to set sampling rate\n");
	275	stk8312_set_mode(data, mode);
	276
	277	return ret;
5e913d27 TB	278	}
5e913d27 TB	279
90bad33a TB	280	static int stk8312_set_range(struct stk8312_data *data, u8 range)
	281	{
	282	int ret;
	283	u8 masked_reg;
	284	u8 mode;
	285	struct i2c_client *client = data->client;
	286
	287	if (range != 1 && range != 2)
	288	return -EINVAL;
	289	else if (range == data->range)
	290	return 0;
	291
	292	mode = data->mode;
	293	/* We need to go in standby mode to modify registers */
	294	ret = stk8312_set_mode(data, STK8312_MODE_STANDBY);
	295	if (ret < 0)
	296	return ret;
	297
	298	ret = i2c_smbus_read_byte_data(client, STK8312_REG_STH);
18422bb3 HK	299	if (ret < 0)
18422bb3 HK	300	goto err_activate;
90bad33a TB	301
	302	masked_reg = ret & (~STK8312_RNG_MASK);
	303	masked_reg \|= range << STK8312_RNG_SHIFT;
	304
	305	ret = i2c_smbus_write_byte_data(client, STK8312_REG_STH, masked_reg);
	306	if (ret < 0)
18422bb3 HK	307	goto err_activate;
	308
	309	data->range = range;
90bad33a TB	310
90bad33a TB	311	return stk8312_set_mode(data, mode);
18422bb3 HK	312
	313	err_activate:
	314	dev_err(&client->dev, "failed to change sensor range\n");
	315	stk8312_set_mode(data, mode);
	316
	317	return ret;
90bad33a TB	318	}
	319
	320	static int stk8312_read_accel(struct stk8312_data *data, u8 address)
	321	{
	322	int ret;
	323	struct i2c_client *client = data->client;
	324
	325	if (address > 2)
	326	return -EINVAL;
	327
	328	ret = i2c_smbus_read_byte_data(client, address);
95c12bba	329	if (ret < 0)
90bad33a	330	dev_err(&client->dev, "register read failed\n");
90bad33a	331
95c12bba	332	return ret;
90bad33a TB	333	}
	334
	335	static int stk8312_read_raw(struct iio_dev *indio_dev,
	336	struct iio_chan_spec const *chan,
	337	int val, int val2, long mask)
	338	{
	339	struct stk8312_data *data = iio_priv(indio_dev);
95c12bba	340	int ret;
90bad33a TB	341
	342	switch (mask) {
	343	case IIO_CHAN_INFO_RAW:
95c12bba TB	344	if (iio_buffer_enabled(indio_dev))
95c12bba TB	345	return -EBUSY;
90bad33a	346	mutex_lock(&data->lock);
95c12bba TB	347	ret = stk8312_set_mode(data, data->mode \| STK8312_MODE_ACTIVE);
	348	if (ret < 0) {
	349	mutex_unlock(&data->lock);
18422bb3	350	return ret;
95c12bba TB	351	}
	352	ret = stk8312_read_accel(data, chan->address);
	353	if (ret < 0) {
	354	stk8312_set_mode(data,
	355	data->mode & (~STK8312_MODE_ACTIVE));
	356	mutex_unlock(&data->lock);
18422bb3	357	return ret;
95c12bba TB	358	}
95c12bba TB	359	*val = sign_extend32(ret, 7);
18422bb3 HK	360	ret = stk8312_set_mode(data,
18422bb3 HK	361	data->mode & (~STK8312_MODE_ACTIVE));
90bad33a	362	mutex_unlock(&data->lock);
18422bb3 HK	363	if (ret < 0)
18422bb3 HK	364	return ret;
90bad33a TB	365	return IIO_VAL_INT;
	366	case IIO_CHAN_INFO_SCALE:
	367	*val = stk8312_scale_table[data->range - 1][0];
	368	*val2 = stk8312_scale_table[data->range - 1][1];
	369	return IIO_VAL_INT_PLUS_MICRO;
5e913d27 TB	370	case IIO_CHAN_INFO_SAMP_FREQ:
	371	*val = stk8312_samp_freq_table[data->sample_rate_idx].val;
	372	*val2 = stk8312_samp_freq_table[data->sample_rate_idx].val2;
	373	return IIO_VAL_INT_PLUS_MICRO;
90bad33a TB	374	}
	375
	376	return -EINVAL;
	377	}
	378
	379	static int stk8312_write_raw(struct iio_dev *indio_dev,
	380	struct iio_chan_spec const *chan,
	381	int val, int val2, long mask)
	382	{
	383	int i;
	384	int index = -1;
	385	int ret;
	386	struct stk8312_data *data = iio_priv(indio_dev);
	387
	388	switch (mask) {
	389	case IIO_CHAN_INFO_SCALE:
	390	for (i = 0; i < ARRAY_SIZE(stk8312_scale_table); i++)
	391	if (val == stk8312_scale_table[i][0] &&
	392	val2 == stk8312_scale_table[i][1]) {
	393	index = i + 1;
	394	break;
	395	}
	396	if (index < 0)
	397	return -EINVAL;
	398
	399	mutex_lock(&data->lock);
	400	ret = stk8312_set_range(data, index);
	401	mutex_unlock(&data->lock);
	402
5e913d27 TB	403	return ret;
	404	case IIO_CHAN_INFO_SAMP_FREQ:
	405	for (i = 0; i < ARRAY_SIZE(stk8312_samp_freq_table); i++)
	406	if (val == stk8312_samp_freq_table[i].val &&
	407	val2 == stk8312_samp_freq_table[i].val2) {
	408	index = i;
	409	break;
	410	}
	411	if (index < 0)
	412	return -EINVAL;
	413	mutex_lock(&data->lock);
	414	ret = stk8312_set_sample_rate(data, index);
	415	mutex_unlock(&data->lock);
	416
90bad33a TB	417	return ret;
	418	}
	419
	420	return -EINVAL;
	421	}
	422
	423	static const struct iio_info stk8312_info = {
	424	.driver_module = THIS_MODULE,
	425	.read_raw = stk8312_read_raw,
	426	.write_raw = stk8312_write_raw,
	427	.attrs = &stk8312_attribute_group,
	428	};
	429
95c12bba TB	430	static irqreturn_t stk8312_trigger_handler(int irq, void *p)
	431	{
	432	struct iio_poll_func *pf = p;
	433	struct iio_dev *indio_dev = pf->indio_dev;
	434	struct stk8312_data *data = iio_priv(indio_dev);
	435	int bit, ret, i = 0;
95c12bba TB	436
	437	mutex_lock(&data->lock);
	438	/*
	439	* Do a bulk read if all channels are requested,
	440	* from 0x00 (XOUT) to 0x02 (ZOUT)
	441	*/
	442	if (*(indio_dev->active_scan_mask) == STK8312_ALL_CHANNEL_MASK) {
	443	ret = i2c_smbus_read_i2c_block_data(data->client,
	444	STK8312_REG_XOUT,
	445	STK8312_ALL_CHANNEL_SIZE,
7a9fbd25	446	data->buffer);
95c12bba TB	447	if (ret < STK8312_ALL_CHANNEL_SIZE) {
	448	dev_err(&data->client->dev, "register read failed\n");
	449	mutex_unlock(&data->lock);
	450	goto err;
	451	}
95c12bba TB	452	} else {
95c12bba TB	453	for_each_set_bit(bit, indio_dev->active_scan_mask,
dca5d284	454	indio_dev->masklength) {
95c12bba TB	455	ret = stk8312_read_accel(data, bit);
	456	if (ret < 0) {
	457	mutex_unlock(&data->lock);
	458	goto err;
	459	}
	460	data->buffer[i++] = ret;
	461	}
	462	}
	463	mutex_unlock(&data->lock);
	464
	465	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
	466	pf->timestamp);
	467	err:
	468	iio_trigger_notify_done(indio_dev->trig);
	469
	470	return IRQ_HANDLED;
	471	}
	472
	473	static irqreturn_t stk8312_data_rdy_trig_poll(int irq, void *private)
	474	{
	475	struct iio_dev *indio_dev = private;
	476	struct stk8312_data *data = iio_priv(indio_dev);
	477
	478	if (data->dready_trigger_on)
	479	iio_trigger_poll(data->dready_trig);
	480
	481	return IRQ_HANDLED;
	482	}
	483
	484	static int stk8312_buffer_preenable(struct iio_dev *indio_dev)
	485	{
	486	struct stk8312_data *data = iio_priv(indio_dev);
	487
	488	return stk8312_set_mode(data, data->mode \| STK8312_MODE_ACTIVE);
	489	}
	490
	491	static int stk8312_buffer_postdisable(struct iio_dev *indio_dev)
	492	{
	493	struct stk8312_data *data = iio_priv(indio_dev);
	494
	495	return stk8312_set_mode(data, data->mode & (~STK8312_MODE_ACTIVE));
	496	}
	497
	498	static const struct iio_buffer_setup_ops stk8312_buffer_setup_ops = {
	499	.preenable = stk8312_buffer_preenable,
	500	.postenable = iio_triggered_buffer_postenable,
	501	.predisable = iio_triggered_buffer_predisable,
	502	.postdisable = stk8312_buffer_postdisable,
	503	};
	504
90bad33a TB	505	static int stk8312_probe(struct i2c_client *client,
	506	const struct i2c_device_id *id)
	507	{
	508	int ret;
	509	struct iio_dev *indio_dev;
	510	struct stk8312_data *data;
	511
	512	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	513	if (!indio_dev) {
	514	dev_err(&client->dev, "iio allocation failed!\n");
	515	return -ENOMEM;
	516	}
	517
	518	data = iio_priv(indio_dev);
	519	data->client = client;
	520	i2c_set_clientdata(client, indio_dev);
	521	mutex_init(&data->lock);
	522
	523	indio_dev->dev.parent = &client->dev;
	524	indio_dev->info = &stk8312_info;
	525	indio_dev->name = STK8312_DRIVER_NAME;
	526	indio_dev->modes = INDIO_DIRECT_MODE;
	527	indio_dev->channels = stk8312_channels;
	528	indio_dev->num_channels = ARRAY_SIZE(stk8312_channels);
	529
	530	/* A software reset is recommended at power-on */
	531	ret = i2c_smbus_write_byte_data(data->client, STK8312_REG_RESET, 0x00);
	532	if (ret < 0) {
	533	dev_err(&client->dev, "failed to reset sensor\n");
	534	return ret;
	535	}
5e913d27	536	data->sample_rate_idx = STK8312_SR_400HZ_IDX;
03ecd50c	537	ret = stk8312_set_range(data, STK8312_RNG_6G);
90bad33a TB	538	if (ret < 0)
	539	return ret;
	540
03ecd50c HK	541	ret = stk8312_set_mode(data,
03ecd50c HK	542	STK8312_MODE_INT_AH_PP \| STK8312_MODE_ACTIVE);
90bad33a TB	543	if (ret < 0)
	544	return ret;
	545
6839c1b0	546	if (client->irq > 0) {
95c12bba TB	547	ret = devm_request_threaded_irq(&client->dev, client->irq,
	548	stk8312_data_rdy_trig_poll,
	549	NULL,
	550	IRQF_TRIGGER_RISING \|
	551	IRQF_ONESHOT,
	552	STK8312_IRQ_NAME,
	553	indio_dev);
	554	if (ret < 0) {
	555	dev_err(&client->dev, "request irq %d failed\n",
	556	client->irq);
	557	goto err_power_off;
	558	}
	559
	560	data->dready_trig = devm_iio_trigger_alloc(&client->dev,
	561	"%s-dev%d",
	562	indio_dev->name,
	563	indio_dev->id);
	564	if (!data->dready_trig) {
	565	ret = -ENOMEM;
	566	goto err_power_off;
	567	}
	568
	569	data->dready_trig->dev.parent = &client->dev;
	570	data->dready_trig->ops = &stk8312_trigger_ops;
	571	iio_trigger_set_drvdata(data->dready_trig, indio_dev);
	572	ret = iio_trigger_register(data->dready_trig);
	573	if (ret) {
	574	dev_err(&client->dev, "iio trigger register failed\n");
	575	goto err_power_off;
	576	}
	577	}
	578
	579	ret = iio_triggered_buffer_setup(indio_dev,
	580	iio_pollfunc_store_time,
	581	stk8312_trigger_handler,
	582	&stk8312_buffer_setup_ops);
	583	if (ret < 0) {
	584	dev_err(&client->dev, "iio triggered buffer setup failed\n");
	585	goto err_trigger_unregister;
	586	}
	587
90bad33a TB	588	ret = iio_device_register(indio_dev);
	589	if (ret < 0) {
	590	dev_err(&client->dev, "device_register failed\n");
95c12bba	591	goto err_buffer_cleanup;
90bad33a TB	592	}
90bad33a TB	593
18422bb3	594	return 0;
95c12bba TB	595
	596	err_buffer_cleanup:
	597	iio_triggered_buffer_cleanup(indio_dev);
	598	err_trigger_unregister:
	599	if (data->dready_trig)
	600	iio_trigger_unregister(data->dready_trig);
	601	err_power_off:
	602	stk8312_set_mode(data, STK8312_MODE_STANDBY);
	603	return ret;
90bad33a TB	604	}
	605
	606	static int stk8312_remove(struct i2c_client *client)
	607	{
	608	struct iio_dev *indio_dev = i2c_get_clientdata(client);
95c12bba	609	struct stk8312_data *data = iio_priv(indio_dev);
90bad33a TB	610
90bad33a TB	611	iio_device_unregister(indio_dev);
95c12bba	612	iio_triggered_buffer_cleanup(indio_dev);
90bad33a	613
95c12bba TB	614	if (data->dready_trig)
	615	iio_trigger_unregister(data->dready_trig);
	616
	617	return stk8312_set_mode(data, STK8312_MODE_STANDBY);
90bad33a TB	618	}
	619
	620	#ifdef CONFIG_PM_SLEEP
	621	static int stk8312_suspend(struct device *dev)
	622	{
	623	struct stk8312_data *data;
	624
	625	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
	626
95c12bba	627	return stk8312_set_mode(data, data->mode & (~STK8312_MODE_ACTIVE));
90bad33a TB	628	}
	629
	630	static int stk8312_resume(struct device *dev)
	631	{
	632	struct stk8312_data *data;
	633
	634	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
	635
95c12bba	636	return stk8312_set_mode(data, data->mode \| STK8312_MODE_ACTIVE);
90bad33a TB	637	}
	638
	639	static SIMPLE_DEV_PM_OPS(stk8312_pm_ops, stk8312_suspend, stk8312_resume);
	640
	641	#define STK8312_PM_OPS (&stk8312_pm_ops)
	642	#else
	643	#define STK8312_PM_OPS NULL
	644	#endif
	645
	646	static const struct i2c_device_id stk8312_i2c_id[] = {
	647	{"STK8312", 0},
	648	{}
	649	};
58e446fc	650	MODULE_DEVICE_TABLE(i2c, stk8312_i2c_id);
90bad33a TB	651
	652	static const struct acpi_device_id stk8312_acpi_id[] = {
	653	{"STK8312", 0},
	654	{}
	655	};
	656
	657	MODULE_DEVICE_TABLE(acpi, stk8312_acpi_id);
	658
	659	static struct i2c_driver stk8312_driver = {
	660	.driver = {
03ecd50c	661	.name = STK8312_DRIVER_NAME,
90bad33a TB	662	.pm = STK8312_PM_OPS,
	663	.acpi_match_table = ACPI_PTR(stk8312_acpi_id),
	664	},
	665	.probe = stk8312_probe,
	666	.remove = stk8312_remove,
	667	.id_table = stk8312_i2c_id,
	668	};
	669
	670	module_i2c_driver(stk8312_driver);
	671
	672	MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
	673	MODULE_DESCRIPTION("STK8312 3-Axis Accelerometer driver");
	674	MODULE_LICENSE("GPL v2");