[mirror_ubuntu-artful-kernel.git] / drivers / iio / accel / stk8ba50.c

/**
 * Sensortek STK8BA50 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.
 *
 * STK8BA50 7-bit I2C address: 0x18.
 */

#include <linux/acpi.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.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 STK8BA50_REG_XOUT			0x02
#define STK8BA50_REG_YOUT			0x04
#define STK8BA50_REG_ZOUT			0x06
#define STK8BA50_REG_RANGE			0x0F
#define STK8BA50_REG_BWSEL			0x10
#define STK8BA50_REG_POWMODE			0x11
#define STK8BA50_REG_SWRST			0x14
#define STK8BA50_REG_INTEN2			0x17
#define STK8BA50_REG_INTMAP2			0x1A

#define STK8BA50_MODE_NORMAL			0
#define STK8BA50_MODE_SUSPEND			1
#define STK8BA50_MODE_POWERBIT			BIT(7)
#define STK8BA50_DATA_SHIFT			6
#define STK8BA50_RESET_CMD			0xB6
#define STK8BA50_SR_1792HZ_IDX			7
#define STK8BA50_DREADY_INT_MASK		0x10
#define STK8BA50_DREADY_INT_MAP			0x81
#define STK8BA50_ALL_CHANNEL_MASK		7
#define STK8BA50_ALL_CHANNEL_SIZE		6

#define STK8BA50_DRIVER_NAME			"stk8ba50"
#define STK8BA50_IRQ_NAME			"stk8ba50_event"

#define STK8BA50_SCALE_AVAIL			"0.0384 0.0767 0.1534 0.3069"

/*
 * The accelerometer has four measurement ranges:
 * +/-2g; +/-4g; +/-8g; +/-16g
 *
 * Acceleration values are 10-bit, 2's complement.
 * Scales are calculated as following:
 *
 * scale1 = (2 + 2) * 9.81 / (2^10 - 1)   = 0.0384
 * scale2 = (4 + 4) * 9.81 / (2^10 - 1)   = 0.0767
 * etc.
 *
 * Scales are stored in this format:
 * { <register value>, <scale value> }
 *
 * Locally, the range is stored as a table index.
 */
static const struct {
	u8 reg_val;
	u32 scale_val;
} stk8ba50_scale_table[] = {
	{3, 38400}, {5, 76700}, {8, 153400}, {12, 306900}
};

/* Sample rates are stored as { <register value>, <Hz value> } */
static const struct {
	u8 reg_val;
	u16 samp_freq;
} stk8ba50_samp_freq_table[] = {
	{0x08, 14},  {0x09, 25},  {0x0A, 56},  {0x0B, 112},
	{0x0C, 224}, {0x0D, 448}, {0x0E, 896}, {0x0F, 1792}
};

/* Used to map scan mask bits to their corresponding channel register. */
static const int stk8ba50_channel_table[] = {
	STK8BA50_REG_XOUT,
	STK8BA50_REG_YOUT,
	STK8BA50_REG_ZOUT
};

struct stk8ba50_data {
	struct i2c_client *client;
	struct mutex lock;
	int range;
	u8 sample_rate_idx;
	struct iio_trigger *dready_trig;
	bool dready_trigger_on;
	/*
	 * 3 x 16-bit channels (10-bit data, 6-bit padding) +
	 * 1 x 16 padding +
	 * 4 x 16 64-bit timestamp
	 */
	s16 buffer[8];
};

#define STK8BA50_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 = 10,						\
		.storagebits = 16,					\
		.shift = STK8BA50_DATA_SHIFT,				\
		.endianness = IIO_CPU,					\
	},								\
}

static const struct iio_chan_spec stk8ba50_channels[] = {
	STK8BA50_ACCEL_CHANNEL(0, STK8BA50_REG_XOUT, X),
	STK8BA50_ACCEL_CHANNEL(1, STK8BA50_REG_YOUT, Y),
	STK8BA50_ACCEL_CHANNEL(2, STK8BA50_REG_ZOUT, Z),
	IIO_CHAN_SOFT_TIMESTAMP(3),
};

static IIO_CONST_ATTR(in_accel_scale_available, STK8BA50_SCALE_AVAIL);

static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("14 25 56 112 224 448 896 1792");

static struct attribute *stk8ba50_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 stk8ba50_attribute_group = {
	.attrs = stk8ba50_attributes
};

static int stk8ba50_read_accel(struct stk8ba50_data *data, u8 reg)
{
	int ret;
	struct i2c_client *client = data->client;

	ret = i2c_smbus_read_word_data(client, reg);
	if (ret < 0) {
		dev_err(&client->dev, "register read failed\n");
		return ret;
	}

	return ret;
}

static int stk8ba50_data_rdy_trigger_set_state(struct iio_trigger *trig,
					       bool state)
{
	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
	struct stk8ba50_data *data = iio_priv(indio_dev);
	int ret;

	if (state)
		ret = i2c_smbus_write_byte_data(data->client,
			STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
	else
		ret = i2c_smbus_write_byte_data(data->client,
			STK8BA50_REG_INTEN2, 0x00);

	if (ret < 0)
		dev_err(&data->client->dev, "failed to set trigger state\n");
	else
		data->dready_trigger_on = state;

	return ret;
}

static const struct iio_trigger_ops stk8ba50_trigger_ops = {
	.set_trigger_state = stk8ba50_data_rdy_trigger_set_state,
	.owner = THIS_MODULE,
};

static int stk8ba50_set_power(struct stk8ba50_data *data, bool mode)
{
	int ret;
	u8 masked_reg;
	struct i2c_client *client = data->client;

	ret = i2c_smbus_read_byte_data(client, STK8BA50_REG_POWMODE);
	if (ret < 0)
		goto exit_err;

	if (mode)
		masked_reg = ret | STK8BA50_MODE_POWERBIT;
	else
		masked_reg = ret & (~STK8BA50_MODE_POWERBIT);

	ret = i2c_smbus_write_byte_data(client, STK8BA50_REG_POWMODE,
					masked_reg);
	if (ret < 0)
		goto exit_err;

	return ret;

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

static int stk8ba50_read_raw(struct iio_dev *indio_dev,
			     struct iio_chan_spec const *chan,
			     int *val, int *val2, long mask)
{
	struct stk8ba50_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 = stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
		if (ret < 0) {
			mutex_unlock(&data->lock);
			return -EINVAL;
		}
		ret = stk8ba50_read_accel(data, chan->address);
		if (ret < 0) {
			stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
			mutex_unlock(&data->lock);
			return -EINVAL;
		}
		*val = sign_extend32(ret >> STK8BA50_DATA_SHIFT, 9);
		stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
		mutex_unlock(&data->lock);
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_SCALE:
		*val = 0;
		*val2 = stk8ba50_scale_table[data->range].scale_val;
		return IIO_VAL_INT_PLUS_MICRO;
	case IIO_CHAN_INFO_SAMP_FREQ:
		*val = stk8ba50_samp_freq_table
				[data->sample_rate_idx].samp_freq;
		*val2 = 0;
		return IIO_VAL_INT;
	}

	return -EINVAL;
}

static int stk8ba50_write_raw(struct iio_dev *indio_dev,
			      struct iio_chan_spec const *chan,
			      int val, int val2, long mask)
{
	int ret;
	int i;
	int index = -1;
	struct stk8ba50_data *data = iio_priv(indio_dev);

	switch (mask) {
	case IIO_CHAN_INFO_SCALE:
		if (val != 0)
			return -EINVAL;

		for (i = 0; i < ARRAY_SIZE(stk8ba50_scale_table); i++)
			if (val2 == stk8ba50_scale_table[i].scale_val) {
				index = i;
				break;
			}
		if (index < 0)
			return -EINVAL;

		ret = i2c_smbus_write_byte_data(data->client,
				STK8BA50_REG_RANGE,
				stk8ba50_scale_table[index].reg_val);
		if (ret < 0)
			dev_err(&data->client->dev,
					"failed to set measurement range\n");
		else
			data->range = index;

		return ret;
	case IIO_CHAN_INFO_SAMP_FREQ:
		for (i = 0; i < ARRAY_SIZE(stk8ba50_samp_freq_table); i++)
			if (val == stk8ba50_samp_freq_table[i].samp_freq) {
				index = i;
				break;
			}
		if (index < 0)
			return -EINVAL;

		ret = i2c_smbus_write_byte_data(data->client,
				STK8BA50_REG_BWSEL,
				stk8ba50_samp_freq_table[index].reg_val);
		if (ret < 0)
			dev_err(&data->client->dev,
					"failed to set sampling rate\n");
		else
			data->sample_rate_idx = index;

		return ret;
	}

	return -EINVAL;
}

static const struct iio_info stk8ba50_info = {
	.driver_module		= THIS_MODULE,
	.read_raw		= stk8ba50_read_raw,
	.write_raw		= stk8ba50_write_raw,
	.attrs			= &stk8ba50_attribute_group,
};

static irqreturn_t stk8ba50_trigger_handler(int irq, void *p)
{
	struct iio_poll_func *pf = p;
	struct iio_dev *indio_dev = pf->indio_dev;
	struct stk8ba50_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 0x02 (XOUT1) to 0x07 (ZOUT2)
	 */
	if (*(indio_dev->active_scan_mask) == STK8BA50_ALL_CHANNEL_MASK) {
		ret = i2c_smbus_read_i2c_block_data(data->client,
						    STK8BA50_REG_XOUT,
						    STK8BA50_ALL_CHANNEL_SIZE,
						    (u8 *)data->buffer);
		if (ret < STK8BA50_ALL_CHANNEL_SIZE) {
			dev_err(&data->client->dev, "register read failed\n");
			goto err;
		}
	} else {
		for_each_set_bit(bit, indio_dev->active_scan_mask,
				 indio_dev->masklength) {
			ret = stk8ba50_read_accel(data,
						  stk8ba50_channel_table[bit]);
			if (ret < 0)
				goto err;

			data->buffer[i++] = ret;
		}
	}
	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
					   pf->timestamp);
err:
	mutex_unlock(&data->lock);
	iio_trigger_notify_done(indio_dev->trig);

	return IRQ_HANDLED;
}

static irqreturn_t stk8ba50_data_rdy_trig_poll(int irq, void *private)
{
	struct iio_dev *indio_dev = private;
	struct stk8ba50_data *data = iio_priv(indio_dev);

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

	return IRQ_HANDLED;
}

static int stk8ba50_buffer_preenable(struct iio_dev *indio_dev)
{
	struct stk8ba50_data *data = iio_priv(indio_dev);

	return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
}

static int stk8ba50_buffer_postdisable(struct iio_dev *indio_dev)
{
	struct stk8ba50_data *data = iio_priv(indio_dev);

	return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
}

static const struct iio_buffer_setup_ops stk8ba50_buffer_setup_ops = {
	.preenable   = stk8ba50_buffer_preenable,
	.postenable  = iio_triggered_buffer_postenable,
	.predisable  = iio_triggered_buffer_predisable,
	.postdisable = stk8ba50_buffer_postdisable,
};

static int stk8ba50_probe(struct i2c_client *client,
			  const struct i2c_device_id *id)
{
	int ret;
	struct iio_dev *indio_dev;
	struct stk8ba50_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 = &stk8ba50_info;
	indio_dev->name = STK8BA50_DRIVER_NAME;
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->channels = stk8ba50_channels;
	indio_dev->num_channels = ARRAY_SIZE(stk8ba50_channels);

	/* Reset all registers on startup */
	ret = i2c_smbus_write_byte_data(client,
			STK8BA50_REG_SWRST, STK8BA50_RESET_CMD);
	if (ret < 0) {
		dev_err(&client->dev, "failed to reset sensor\n");
		goto err_power_off;
	}

	/* The default range is +/-2g */
	data->range = 0;

	/* The default sampling rate is 1792 Hz (maximum) */
	data->sample_rate_idx = STK8BA50_SR_1792HZ_IDX;

	/* Set up interrupts */
	ret = i2c_smbus_write_byte_data(client,
			STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
	if (ret < 0) {
		dev_err(&client->dev, "failed to set up interrupts\n");
		goto err_power_off;
	}
	ret = i2c_smbus_write_byte_data(client,
			STK8BA50_REG_INTMAP2, STK8BA50_DREADY_INT_MAP);
	if (ret < 0) {
		dev_err(&client->dev, "failed to set up interrupts\n");
		goto err_power_off;
	}

	if (client->irq > 0) {
		ret = devm_request_threaded_irq(&client->dev, client->irq,
						stk8ba50_data_rdy_trig_poll,
						NULL,
						IRQF_TRIGGER_RISING |
						IRQF_ONESHOT,
						STK8BA50_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 = &stk8ba50_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,
					 stk8ba50_trigger_handler,
					 &stk8ba50_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 ret;

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:
	stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
	return ret;
}

static int stk8ba50_remove(struct i2c_client *client)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(client);
	struct stk8ba50_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 stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
}

#ifdef CONFIG_PM_SLEEP
static int stk8ba50_suspend(struct device *dev)
{
	struct stk8ba50_data *data;

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

	return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
}

static int stk8ba50_resume(struct device *dev)
{
	struct stk8ba50_data *data;

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

	return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
}

static SIMPLE_DEV_PM_OPS(stk8ba50_pm_ops, stk8ba50_suspend, stk8ba50_resume);

#define STK8BA50_PM_OPS (&stk8ba50_pm_ops)
#else
#define STK8BA50_PM_OPS NULL
#endif

static const struct i2c_device_id stk8ba50_i2c_id[] = {
	{"stk8ba50", 0},
	{}
};
MODULE_DEVICE_TABLE(i2c, stk8ba50_i2c_id);

static const struct acpi_device_id stk8ba50_acpi_id[] = {
	{"STK8BA50", 0},
	{}
};

MODULE_DEVICE_TABLE(acpi, stk8ba50_acpi_id);

static struct i2c_driver stk8ba50_driver = {
	.driver = {
		.name = "stk8ba50",
		.pm = STK8BA50_PM_OPS,
		.acpi_match_table = ACPI_PTR(stk8ba50_acpi_id),
	},
	.probe =            stk8ba50_probe,
	.remove =           stk8ba50_remove,
	.id_table =         stk8ba50_i2c_id,
};

module_i2c_driver(stk8ba50_driver);

MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
MODULE_DESCRIPTION("STK8BA50 3-Axis Accelerometer driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
884ca456 TB	1	/**
	2	* Sensortek STK8BA50 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	* STK8BA50 7-bit I2C address: 0x18.
	11	*/
	12
	13	#include <linux/acpi.h>
	14	#include <linux/i2c.h>
db6a19b8	15	#include <linux/interrupt.h>
884ca456 TB	16	#include <linux/kernel.h>
884ca456 TB	17	#include <linux/module.h>
db6a19b8	18	#include <linux/iio/buffer.h>
884ca456 TB	19	#include <linux/iio/iio.h>
884ca456 TB	20	#include <linux/iio/sysfs.h>
db6a19b8 TB	21	#include <linux/iio/trigger.h>
	22	#include <linux/iio/triggered_buffer.h>
	23	#include <linux/iio/trigger_consumer.h>
884ca456 TB	24
	25	#define STK8BA50_REG_XOUT 0x02
	26	#define STK8BA50_REG_YOUT 0x04
	27	#define STK8BA50_REG_ZOUT 0x06
	28	#define STK8BA50_REG_RANGE 0x0F
eb2c9ce2	29	#define STK8BA50_REG_BWSEL 0x10
884ca456 TB	30	#define STK8BA50_REG_POWMODE 0x11
884ca456 TB	31	#define STK8BA50_REG_SWRST 0x14
db6a19b8 TB	32	#define STK8BA50_REG_INTEN2 0x17
db6a19b8 TB	33	#define STK8BA50_REG_INTMAP2 0x1A
884ca456 TB	34
	35	#define STK8BA50_MODE_NORMAL 0
	36	#define STK8BA50_MODE_SUSPEND 1
	37	#define STK8BA50_MODE_POWERBIT BIT(7)
	38	#define STK8BA50_DATA_SHIFT 6
	39	#define STK8BA50_RESET_CMD 0xB6
eb2c9ce2	40	#define STK8BA50_SR_1792HZ_IDX 7
db6a19b8 TB	41	#define STK8BA50_DREADY_INT_MASK 0x10
	42	#define STK8BA50_DREADY_INT_MAP 0x81
	43	#define STK8BA50_ALL_CHANNEL_MASK 7
	44	#define STK8BA50_ALL_CHANNEL_SIZE 6
884ca456 TB	45
884ca456 TB	46	#define STK8BA50_DRIVER_NAME "stk8ba50"
db6a19b8	47	#define STK8BA50_IRQ_NAME "stk8ba50_event"
884ca456 TB	48
	49	#define STK8BA50_SCALE_AVAIL "0.0384 0.0767 0.1534 0.3069"
	50
	51	/*
	52	* The accelerometer has four measurement ranges:
	53	* +/-2g; +/-4g; +/-8g; +/-16g
	54	*
	55	* Acceleration values are 10-bit, 2's complement.
	56	* Scales are calculated as following:
	57	*
	58	* scale1 = (2 + 2) * 9.81 / (2^10 - 1) = 0.0384
	59	* scale2 = (4 + 4) * 9.81 / (2^10 - 1) = 0.0767
	60	* etc.
	61	*
	62	* Scales are stored in this format:
	63	* { <register value>, <scale value> }
	64	*
	65	* Locally, the range is stored as a table index.
	66	*/
003f4880 TB	67	static const struct {
	68	u8 reg_val;
	69	u32 scale_val;
	70	} stk8ba50_scale_table[] = {
884ca456 TB	71	{3, 38400}, {5, 76700}, {8, 153400}, {12, 306900}
	72	};
	73
eb2c9ce2 TB	74	/* Sample rates are stored as { <register value>, <Hz value> } */
	75	static const struct {
	76	u8 reg_val;
	77	u16 samp_freq;
	78	} stk8ba50_samp_freq_table[] = {
	79	{0x08, 14}, {0x09, 25}, {0x0A, 56}, {0x0B, 112},
	80	{0x0C, 224}, {0x0D, 448}, {0x0E, 896}, {0x0F, 1792}
	81	};
	82
db6a19b8 TB	83	/* Used to map scan mask bits to their corresponding channel register. */
	84	static const int stk8ba50_channel_table[] = {
	85	STK8BA50_REG_XOUT,
	86	STK8BA50_REG_YOUT,
	87	STK8BA50_REG_ZOUT
	88	};
	89
884ca456 TB	90	struct stk8ba50_data {
	91	struct i2c_client *client;
	92	struct mutex lock;
	93	int range;
eb2c9ce2	94	u8 sample_rate_idx;
db6a19b8 TB	95	struct iio_trigger *dready_trig;
	96	bool dready_trigger_on;
	97	/*
	98	* 3 x 16-bit channels (10-bit data, 6-bit padding) +
	99	* 1 x 16 padding +
	100	* 4 x 16 64-bit timestamp
	101	*/
	102	s16 buffer[8];
884ca456 TB	103	};
884ca456 TB	104
db6a19b8	105	#define STK8BA50_ACCEL_CHANNEL(index, reg, axis) { \
eb2c9ce2 TB	106	.type = IIO_ACCEL, \
	107	.address = reg, \
	108	.modified = 1, \
	109	.channel2 = IIO_MOD_##axis, \
	110	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
	111	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
	112	BIT(IIO_CHAN_INFO_SAMP_FREQ), \
db6a19b8 TB	113	.scan_index = index, \
	114	.scan_type = { \
	115	.sign = 's', \
	116	.realbits = 10, \
	117	.storagebits = 16, \
	118	.shift = STK8BA50_DATA_SHIFT, \
	119	.endianness = IIO_CPU, \
	120	}, \
884ca456 TB	121	}
	122
	123	static const struct iio_chan_spec stk8ba50_channels[] = {
db6a19b8 TB	124	STK8BA50_ACCEL_CHANNEL(0, STK8BA50_REG_XOUT, X),
	125	STK8BA50_ACCEL_CHANNEL(1, STK8BA50_REG_YOUT, Y),
	126	STK8BA50_ACCEL_CHANNEL(2, STK8BA50_REG_ZOUT, Z),
	127	IIO_CHAN_SOFT_TIMESTAMP(3),
884ca456 TB	128	};
	129
	130	static IIO_CONST_ATTR(in_accel_scale_available, STK8BA50_SCALE_AVAIL);
	131
eb2c9ce2 TB	132	static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("14 25 56 112 224 448 896 1792");
eb2c9ce2 TB	133
884ca456 TB	134	static struct attribute *stk8ba50_attributes[] = {
884ca456 TB	135	&iio_const_attr_in_accel_scale_available.dev_attr.attr,
eb2c9ce2	136	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
884ca456 TB	137	NULL,
	138	};
	139
	140	static const struct attribute_group stk8ba50_attribute_group = {
	141	.attrs = stk8ba50_attributes
	142	};
	143
	144	static int stk8ba50_read_accel(struct stk8ba50_data *data, u8 reg)
	145	{
	146	int ret;
	147	struct i2c_client *client = data->client;
	148
	149	ret = i2c_smbus_read_word_data(client, reg);
	150	if (ret < 0) {
	151	dev_err(&client->dev, "register read failed\n");
	152	return ret;
	153	}
	154
db6a19b8 TB	155	return ret;
	156	}
	157
	158	static int stk8ba50_data_rdy_trigger_set_state(struct iio_trigger *trig,
	159	bool state)
	160	{
	161	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
	162	struct stk8ba50_data *data = iio_priv(indio_dev);
	163	int ret;
	164
	165	if (state)
	166	ret = i2c_smbus_write_byte_data(data->client,
	167	STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
	168	else
	169	ret = i2c_smbus_write_byte_data(data->client,
	170	STK8BA50_REG_INTEN2, 0x00);
	171
	172	if (ret < 0)
	173	dev_err(&data->client->dev, "failed to set trigger state\n");
	174	else
	175	data->dready_trigger_on = state;
	176
	177	return ret;
	178	}
	179
	180	static const struct iio_trigger_ops stk8ba50_trigger_ops = {
	181	.set_trigger_state = stk8ba50_data_rdy_trigger_set_state,
	182	.owner = THIS_MODULE,
	183	};
	184
	185	static int stk8ba50_set_power(struct stk8ba50_data *data, bool mode)
	186	{
	187	int ret;
	188	u8 masked_reg;
	189	struct i2c_client *client = data->client;
	190
	191	ret = i2c_smbus_read_byte_data(client, STK8BA50_REG_POWMODE);
	192	if (ret < 0)
	193	goto exit_err;
	194
	195	if (mode)
	196	masked_reg = ret \| STK8BA50_MODE_POWERBIT;
	197	else
	198	masked_reg = ret & (~STK8BA50_MODE_POWERBIT);
	199
	200	ret = i2c_smbus_write_byte_data(client, STK8BA50_REG_POWMODE,
	201	masked_reg);
	202	if (ret < 0)
	203	goto exit_err;
	204
	205	return ret;
	206
	207	exit_err:
	208	dev_err(&client->dev, "failed to change sensor mode\n");
	209	return ret;
884ca456 TB	210	}
	211
	212	static int stk8ba50_read_raw(struct iio_dev *indio_dev,
	213	struct iio_chan_spec const *chan,
	214	int val, int val2, long mask)
	215	{
	216	struct stk8ba50_data *data = iio_priv(indio_dev);
db6a19b8	217	int ret;
884ca456 TB	218
	219	switch (mask) {
	220	case IIO_CHAN_INFO_RAW:
db6a19b8 TB	221	if (iio_buffer_enabled(indio_dev))
db6a19b8 TB	222	return -EBUSY;
884ca456	223	mutex_lock(&data->lock);
db6a19b8 TB	224	ret = stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
	225	if (ret < 0) {
	226	mutex_unlock(&data->lock);
	227	return -EINVAL;
	228	}
	229	ret = stk8ba50_read_accel(data, chan->address);
	230	if (ret < 0) {
	231	stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
	232	mutex_unlock(&data->lock);
	233	return -EINVAL;
	234	}
	235	*val = sign_extend32(ret >> STK8BA50_DATA_SHIFT, 9);
	236	stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
884ca456 TB	237	mutex_unlock(&data->lock);
	238	return IIO_VAL_INT;
	239	case IIO_CHAN_INFO_SCALE:
	240	*val = 0;
003f4880	241	*val2 = stk8ba50_scale_table[data->range].scale_val;
884ca456	242	return IIO_VAL_INT_PLUS_MICRO;
eb2c9ce2 TB	243	case IIO_CHAN_INFO_SAMP_FREQ:
	244	*val = stk8ba50_samp_freq_table
	245	[data->sample_rate_idx].samp_freq;
	246	*val2 = 0;
	247	return IIO_VAL_INT;
884ca456 TB	248	}
	249
	250	return -EINVAL;
	251	}
	252
	253	static int stk8ba50_write_raw(struct iio_dev *indio_dev,
	254	struct iio_chan_spec const *chan,
	255	int val, int val2, long mask)
	256	{
	257	int ret;
	258	int i;
	259	int index = -1;
	260	struct stk8ba50_data *data = iio_priv(indio_dev);
	261
	262	switch (mask) {
	263	case IIO_CHAN_INFO_SCALE:
	264	if (val != 0)
	265	return -EINVAL;
	266
	267	for (i = 0; i < ARRAY_SIZE(stk8ba50_scale_table); i++)
003f4880	268	if (val2 == stk8ba50_scale_table[i].scale_val) {
884ca456 TB	269	index = i;
	270	break;
	271	}
	272	if (index < 0)
	273	return -EINVAL;
	274
	275	ret = i2c_smbus_write_byte_data(data->client,
	276	STK8BA50_REG_RANGE,
003f4880	277	stk8ba50_scale_table[index].reg_val);
884ca456 TB	278	if (ret < 0)
	279	dev_err(&data->client->dev,
	280	"failed to set measurement range\n");
	281	else
	282	data->range = index;
	283
eb2c9ce2 TB	284	return ret;
	285	case IIO_CHAN_INFO_SAMP_FREQ:
	286	for (i = 0; i < ARRAY_SIZE(stk8ba50_samp_freq_table); i++)
	287	if (val == stk8ba50_samp_freq_table[i].samp_freq) {
	288	index = i;
	289	break;
	290	}
	291	if (index < 0)
	292	return -EINVAL;
	293
	294	ret = i2c_smbus_write_byte_data(data->client,
	295	STK8BA50_REG_BWSEL,
	296	stk8ba50_samp_freq_table[index].reg_val);
	297	if (ret < 0)
	298	dev_err(&data->client->dev,
	299	"failed to set sampling rate\n");
	300	else
	301	data->sample_rate_idx = index;
	302
884ca456 TB	303	return ret;
	304	}
	305
	306	return -EINVAL;
	307	}
	308
	309	static const struct iio_info stk8ba50_info = {
	310	.driver_module = THIS_MODULE,
	311	.read_raw = stk8ba50_read_raw,
	312	.write_raw = stk8ba50_write_raw,
	313	.attrs = &stk8ba50_attribute_group,
	314	};
	315
db6a19b8 TB	316	static irqreturn_t stk8ba50_trigger_handler(int irq, void *p)
	317	{
	318	struct iio_poll_func *pf = p;
	319	struct iio_dev *indio_dev = pf->indio_dev;
	320	struct stk8ba50_data *data = iio_priv(indio_dev);
	321	int bit, ret, i = 0;
	322
	323	mutex_lock(&data->lock);
	324	/*
	325	* Do a bulk read if all channels are requested,
	326	* from 0x02 (XOUT1) to 0x07 (ZOUT2)
	327	*/
	328	if (*(indio_dev->active_scan_mask) == STK8BA50_ALL_CHANNEL_MASK) {
	329	ret = i2c_smbus_read_i2c_block_data(data->client,
	330	STK8BA50_REG_XOUT,
	331	STK8BA50_ALL_CHANNEL_SIZE,
	332	(u8 *)data->buffer);
	333	if (ret < STK8BA50_ALL_CHANNEL_SIZE) {
	334	dev_err(&data->client->dev, "register read failed\n");
	335	goto err;
	336	}
	337	} else {
	338	for_each_set_bit(bit, indio_dev->active_scan_mask,
	339	indio_dev->masklength) {
	340	ret = stk8ba50_read_accel(data,
	341	stk8ba50_channel_table[bit]);
	342	if (ret < 0)
	343	goto err;
	344
	345	data->buffer[i++] = ret;
	346	}
	347	}
	348	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
	349	pf->timestamp);
	350	err:
	351	mutex_unlock(&data->lock);
	352	iio_trigger_notify_done(indio_dev->trig);
	353
	354	return IRQ_HANDLED;
	355	}
	356
	357	static irqreturn_t stk8ba50_data_rdy_trig_poll(int irq, void *private)
	358	{
	359	struct iio_dev *indio_dev = private;
	360	struct stk8ba50_data *data = iio_priv(indio_dev);
	361
	362	if (data->dready_trigger_on)
	363	iio_trigger_poll(data->dready_trig);
	364
	365	return IRQ_HANDLED;
	366	}
	367
	368	static int stk8ba50_buffer_preenable(struct iio_dev *indio_dev)
	369	{
	370	struct stk8ba50_data *data = iio_priv(indio_dev);
	371
	372	return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
	373	}
	374
	375	static int stk8ba50_buffer_postdisable(struct iio_dev *indio_dev)
	376	{
	377	struct stk8ba50_data *data = iio_priv(indio_dev);
	378
	379	return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
380	}
381
382	static const struct iio_buffer_setup_ops stk8ba50_buffer_setup_ops = {
383	.preenable = stk8ba50_buffer_preenable,
384	.postenable = iio_triggered_buffer_postenable,
385	.predisable = iio_triggered_buffer_predisable,
386	.postdisable = stk8ba50_buffer_postdisable,
387	};
388
884ca456 TB	389	static int stk8ba50_probe(struct i2c_client *client,
	390	const struct i2c_device_id *id)
	391	{
	392	int ret;
	393	struct iio_dev *indio_dev;
	394	struct stk8ba50_data *data;
	395
	396	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	397	if (!indio_dev) {
	398	dev_err(&client->dev, "iio allocation failed!\n");
	399	return -ENOMEM;
	400	}
	401
	402	data = iio_priv(indio_dev);
	403	data->client = client;
	404	i2c_set_clientdata(client, indio_dev);
	405	mutex_init(&data->lock);
	406
	407	indio_dev->dev.parent = &client->dev;
	408	indio_dev->info = &stk8ba50_info;
	409	indio_dev->name = STK8BA50_DRIVER_NAME;
	410	indio_dev->modes = INDIO_DIRECT_MODE;
	411	indio_dev->channels = stk8ba50_channels;
	412	indio_dev->num_channels = ARRAY_SIZE(stk8ba50_channels);
	413
	414	/* Reset all registers on startup */
	415	ret = i2c_smbus_write_byte_data(client,
	416	STK8BA50_REG_SWRST, STK8BA50_RESET_CMD);
	417	if (ret < 0) {
	418	dev_err(&client->dev, "failed to reset sensor\n");
db42a9be	419	goto err_power_off;
884ca456 TB	420	}
	421
	422	/* The default range is +/-2g */
	423	data->range = 0;
	424
eb2c9ce2 TB	425	/* The default sampling rate is 1792 Hz (maximum) */
	426	data->sample_rate_idx = STK8BA50_SR_1792HZ_IDX;
	427
db6a19b8 TB	428	/* Set up interrupts */
	429	ret = i2c_smbus_write_byte_data(client,
	430	STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
	431	if (ret < 0) {
	432	dev_err(&client->dev, "failed to set up interrupts\n");
	433	goto err_power_off;
	434	}
	435	ret = i2c_smbus_write_byte_data(client,
	436	STK8BA50_REG_INTMAP2, STK8BA50_DREADY_INT_MAP);
	437	if (ret < 0) {
	438	dev_err(&client->dev, "failed to set up interrupts\n");
	439	goto err_power_off;
	440	}
	441
6839c1b0	442	if (client->irq > 0) {
db6a19b8 TB	443	ret = devm_request_threaded_irq(&client->dev, client->irq,
	444	stk8ba50_data_rdy_trig_poll,
	445	NULL,
	446	IRQF_TRIGGER_RISING \|
	447	IRQF_ONESHOT,
	448	STK8BA50_IRQ_NAME,
	449	indio_dev);
	450	if (ret < 0) {
	451	dev_err(&client->dev, "request irq %d failed\n",
	452	client->irq);
	453	goto err_power_off;
	454	}
	455
	456	data->dready_trig = devm_iio_trigger_alloc(&client->dev,
	457	"%s-dev%d",
	458	indio_dev->name,
	459	indio_dev->id);
	460	if (!data->dready_trig) {
	461	ret = -ENOMEM;
	462	goto err_power_off;
	463	}
	464
	465	data->dready_trig->dev.parent = &client->dev;
	466	data->dready_trig->ops = &stk8ba50_trigger_ops;
	467	iio_trigger_set_drvdata(data->dready_trig, indio_dev);
	468	ret = iio_trigger_register(data->dready_trig);
	469	if (ret) {
	470	dev_err(&client->dev, "iio trigger register failed\n");
	471	goto err_power_off;
	472	}
	473	}
	474
	475	ret = iio_triggered_buffer_setup(indio_dev,
	476	iio_pollfunc_store_time,
	477	stk8ba50_trigger_handler,
	478	&stk8ba50_buffer_setup_ops);
	479	if (ret < 0) {
	480	dev_err(&client->dev, "iio triggered buffer setup failed\n");
	481	goto err_trigger_unregister;
	482	}
	483
884ca456 TB	484	ret = iio_device_register(indio_dev);
	485	if (ret < 0) {
	486	dev_err(&client->dev, "device_register failed\n");
db6a19b8	487	goto err_buffer_cleanup;
884ca456 TB	488	}
	489
	490	return ret;
db42a9be	491
db6a19b8 TB	492	err_buffer_cleanup:
	493	iio_triggered_buffer_cleanup(indio_dev);
	494	err_trigger_unregister:
	495	if (data->dready_trig)
	496	iio_trigger_unregister(data->dready_trig);
db42a9be TB	497	err_power_off:
	498	stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
	499	return ret;
884ca456 TB	500	}
	501
	502	static int stk8ba50_remove(struct i2c_client *client)
	503	{
	504	struct iio_dev *indio_dev = i2c_get_clientdata(client);
db6a19b8	505	struct stk8ba50_data *data = iio_priv(indio_dev);
884ca456 TB	506
884ca456 TB	507	iio_device_unregister(indio_dev);
db6a19b8 TB	508	iio_triggered_buffer_cleanup(indio_dev);
	509
	510	if (data->dready_trig)
	511	iio_trigger_unregister(data->dready_trig);
884ca456	512
db6a19b8	513	return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
884ca456 TB	514	}
	515
	516	#ifdef CONFIG_PM_SLEEP
	517	static int stk8ba50_suspend(struct device *dev)
	518	{
	519	struct stk8ba50_data *data;
	520
	521	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
	522
	523	return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
	524	}
	525
	526	static int stk8ba50_resume(struct device *dev)
	527	{
	528	struct stk8ba50_data *data;
	529
	530	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
	531
	532	return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
	533	}
	534
	535	static SIMPLE_DEV_PM_OPS(stk8ba50_pm_ops, stk8ba50_suspend, stk8ba50_resume);
	536
	537	#define STK8BA50_PM_OPS (&stk8ba50_pm_ops)
	538	#else
	539	#define STK8BA50_PM_OPS NULL
	540	#endif
	541
	542	static const struct i2c_device_id stk8ba50_i2c_id[] = {
	543	{"stk8ba50", 0},
	544	{}
	545	};
58e446fc	546	MODULE_DEVICE_TABLE(i2c, stk8ba50_i2c_id);
884ca456 TB	547
	548	static const struct acpi_device_id stk8ba50_acpi_id[] = {
	549	{"STK8BA50", 0},
	550	{}
	551	};
	552
	553	MODULE_DEVICE_TABLE(acpi, stk8ba50_acpi_id);
	554
	555	static struct i2c_driver stk8ba50_driver = {
	556	.driver = {
	557	.name = "stk8ba50",
	558	.pm = STK8BA50_PM_OPS,
	559	.acpi_match_table = ACPI_PTR(stk8ba50_acpi_id),
	560	},
	561	.probe = stk8ba50_probe,
	562	.remove = stk8ba50_remove,
	563	.id_table = stk8ba50_i2c_id,
	564	};
	565
	566	module_i2c_driver(stk8ba50_driver);
	567
	568	MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
	569	MODULE_DESCRIPTION("STK8BA50 3-Axis Accelerometer driver");
	570	MODULE_LICENSE("GPL v2");