[linux-2.6-block.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/gpio/consumer.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_GPIO				"stk8ba50_gpio"
#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_gpio_probe(struct i2c_client *client)
{
	struct device *dev;
	struct gpio_desc *gpio;
	int ret;

	if (!client)
		return -EINVAL;

	dev = &client->dev;

	/* data ready gpio interrupt pin */
	gpio = devm_gpiod_get_index(dev, STK8BA50_GPIO, 0, GPIOD_IN);
	if (IS_ERR(gpio)) {
		dev_err(dev, "acpi gpio get index failed\n");
		return PTR_ERR(gpio);
	}

	ret = gpiod_to_irq(gpio);
	dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);

	return ret;
}

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)
		client->irq = stk8ba50_gpio_probe(client);

	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>
db6a19b8	14	#include <linux/gpio/consumer.h>
884ca456	15	#include <linux/i2c.h>
db6a19b8	16	#include <linux/interrupt.h>
884ca456 TB	17	#include <linux/kernel.h>
884ca456 TB	18	#include <linux/module.h>
db6a19b8	19	#include <linux/iio/buffer.h>
884ca456 TB	20	#include <linux/iio/iio.h>
884ca456 TB	21	#include <linux/iio/sysfs.h>
db6a19b8 TB	22	#include <linux/iio/trigger.h>
	23	#include <linux/iio/triggered_buffer.h>
	24	#include <linux/iio/trigger_consumer.h>
884ca456 TB	25
	26	#define STK8BA50_REG_XOUT 0x02
	27	#define STK8BA50_REG_YOUT 0x04
	28	#define STK8BA50_REG_ZOUT 0x06
	29	#define STK8BA50_REG_RANGE 0x0F
eb2c9ce2	30	#define STK8BA50_REG_BWSEL 0x10
884ca456 TB	31	#define STK8BA50_REG_POWMODE 0x11
884ca456 TB	32	#define STK8BA50_REG_SWRST 0x14
db6a19b8 TB	33	#define STK8BA50_REG_INTEN2 0x17
db6a19b8 TB	34	#define STK8BA50_REG_INTMAP2 0x1A
884ca456 TB	35
	36	#define STK8BA50_MODE_NORMAL 0
	37	#define STK8BA50_MODE_SUSPEND 1
	38	#define STK8BA50_MODE_POWERBIT BIT(7)
	39	#define STK8BA50_DATA_SHIFT 6
	40	#define STK8BA50_RESET_CMD 0xB6
eb2c9ce2	41	#define STK8BA50_SR_1792HZ_IDX 7
db6a19b8 TB	42	#define STK8BA50_DREADY_INT_MASK 0x10
	43	#define STK8BA50_DREADY_INT_MAP 0x81
	44	#define STK8BA50_ALL_CHANNEL_MASK 7
	45	#define STK8BA50_ALL_CHANNEL_SIZE 6
884ca456 TB	46
884ca456 TB	47	#define STK8BA50_DRIVER_NAME "stk8ba50"
db6a19b8 TB	48	#define STK8BA50_GPIO "stk8ba50_gpio"
db6a19b8 TB	49	#define STK8BA50_IRQ_NAME "stk8ba50_event"
884ca456 TB	50
	51	#define STK8BA50_SCALE_AVAIL "0.0384 0.0767 0.1534 0.3069"
	52
	53	/*
	54	* The accelerometer has four measurement ranges:
	55	* +/-2g; +/-4g; +/-8g; +/-16g
	56	*
	57	* Acceleration values are 10-bit, 2's complement.
	58	* Scales are calculated as following:
	59	*
	60	* scale1 = (2 + 2) * 9.81 / (2^10 - 1) = 0.0384
	61	* scale2 = (4 + 4) * 9.81 / (2^10 - 1) = 0.0767
	62	* etc.
	63	*
	64	* Scales are stored in this format:
	65	* { <register value>, <scale value> }
	66	*
	67	* Locally, the range is stored as a table index.
	68	*/
003f4880 TB	69	static const struct {
	70	u8 reg_val;
	71	u32 scale_val;
	72	} stk8ba50_scale_table[] = {
884ca456 TB	73	{3, 38400}, {5, 76700}, {8, 153400}, {12, 306900}
	74	};
	75
eb2c9ce2 TB	76	/* Sample rates are stored as { <register value>, <Hz value> } */
	77	static const struct {
	78	u8 reg_val;
	79	u16 samp_freq;
	80	} stk8ba50_samp_freq_table[] = {
	81	{0x08, 14}, {0x09, 25}, {0x0A, 56}, {0x0B, 112},
	82	{0x0C, 224}, {0x0D, 448}, {0x0E, 896}, {0x0F, 1792}
	83	};
	84
db6a19b8 TB	85	/* Used to map scan mask bits to their corresponding channel register. */
	86	static const int stk8ba50_channel_table[] = {
	87	STK8BA50_REG_XOUT,
	88	STK8BA50_REG_YOUT,
	89	STK8BA50_REG_ZOUT
	90	};
	91
884ca456 TB	92	struct stk8ba50_data {
	93	struct i2c_client *client;
	94	struct mutex lock;
	95	int range;
eb2c9ce2	96	u8 sample_rate_idx;
db6a19b8 TB	97	struct iio_trigger *dready_trig;
	98	bool dready_trigger_on;
	99	/*
	100	* 3 x 16-bit channels (10-bit data, 6-bit padding) +
	101	* 1 x 16 padding +
	102	* 4 x 16 64-bit timestamp
	103	*/
	104	s16 buffer[8];
884ca456 TB	105	};
884ca456 TB	106
db6a19b8	107	#define STK8BA50_ACCEL_CHANNEL(index, reg, axis) { \
eb2c9ce2 TB	108	.type = IIO_ACCEL, \
	109	.address = reg, \
	110	.modified = 1, \
	111	.channel2 = IIO_MOD_##axis, \
	112	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
	113	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
	114	BIT(IIO_CHAN_INFO_SAMP_FREQ), \
db6a19b8 TB	115	.scan_index = index, \
	116	.scan_type = { \
	117	.sign = 's', \
	118	.realbits = 10, \
	119	.storagebits = 16, \
	120	.shift = STK8BA50_DATA_SHIFT, \
	121	.endianness = IIO_CPU, \
	122	}, \
884ca456 TB	123	}
	124
	125	static const struct iio_chan_spec stk8ba50_channels[] = {
db6a19b8 TB	126	STK8BA50_ACCEL_CHANNEL(0, STK8BA50_REG_XOUT, X),
	127	STK8BA50_ACCEL_CHANNEL(1, STK8BA50_REG_YOUT, Y),
	128	STK8BA50_ACCEL_CHANNEL(2, STK8BA50_REG_ZOUT, Z),
	129	IIO_CHAN_SOFT_TIMESTAMP(3),
884ca456 TB	130	};
	131
	132	static IIO_CONST_ATTR(in_accel_scale_available, STK8BA50_SCALE_AVAIL);
	133
eb2c9ce2 TB	134	static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("14 25 56 112 224 448 896 1792");
eb2c9ce2 TB	135
884ca456 TB	136	static struct attribute *stk8ba50_attributes[] = {
884ca456 TB	137	&iio_const_attr_in_accel_scale_available.dev_attr.attr,
eb2c9ce2	138	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
884ca456 TB	139	NULL,
	140	};
	141
	142	static const struct attribute_group stk8ba50_attribute_group = {
	143	.attrs = stk8ba50_attributes
	144	};
	145
	146	static int stk8ba50_read_accel(struct stk8ba50_data *data, u8 reg)
	147	{
	148	int ret;
	149	struct i2c_client *client = data->client;
	150
	151	ret = i2c_smbus_read_word_data(client, reg);
	152	if (ret < 0) {
	153	dev_err(&client->dev, "register read failed\n");
	154	return ret;
	155	}
	156
db6a19b8 TB	157	return ret;
	158	}
	159
	160	static int stk8ba50_data_rdy_trigger_set_state(struct iio_trigger *trig,
	161	bool state)
	162	{
	163	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
	164	struct stk8ba50_data *data = iio_priv(indio_dev);
	165	int ret;
	166
	167	if (state)
	168	ret = i2c_smbus_write_byte_data(data->client,
	169	STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
	170	else
	171	ret = i2c_smbus_write_byte_data(data->client,
	172	STK8BA50_REG_INTEN2, 0x00);
	173
	174	if (ret < 0)
	175	dev_err(&data->client->dev, "failed to set trigger state\n");
	176	else
	177	data->dready_trigger_on = state;
	178
	179	return ret;
	180	}
	181
	182	static const struct iio_trigger_ops stk8ba50_trigger_ops = {
	183	.set_trigger_state = stk8ba50_data_rdy_trigger_set_state,
	184	.owner = THIS_MODULE,
	185	};
	186
	187	static int stk8ba50_set_power(struct stk8ba50_data *data, bool mode)
	188	{
	189	int ret;
	190	u8 masked_reg;
	191	struct i2c_client *client = data->client;
	192
	193	ret = i2c_smbus_read_byte_data(client, STK8BA50_REG_POWMODE);
	194	if (ret < 0)
	195	goto exit_err;
	196
	197	if (mode)
	198	masked_reg = ret \| STK8BA50_MODE_POWERBIT;
	199	else
	200	masked_reg = ret & (~STK8BA50_MODE_POWERBIT);
	201
	202	ret = i2c_smbus_write_byte_data(client, STK8BA50_REG_POWMODE,
	203	masked_reg);
	204	if (ret < 0)
	205	goto exit_err;
	206
	207	return ret;
	208
	209	exit_err:
	210	dev_err(&client->dev, "failed to change sensor mode\n");
	211	return ret;
884ca456 TB	212	}
	213
	214	static int stk8ba50_read_raw(struct iio_dev *indio_dev,
	215	struct iio_chan_spec const *chan,
	216	int val, int val2, long mask)
	217	{
	218	struct stk8ba50_data *data = iio_priv(indio_dev);
db6a19b8	219	int ret;
884ca456 TB	220
	221	switch (mask) {
	222	case IIO_CHAN_INFO_RAW:
db6a19b8 TB	223	if (iio_buffer_enabled(indio_dev))
db6a19b8 TB	224	return -EBUSY;
884ca456	225	mutex_lock(&data->lock);
db6a19b8 TB	226	ret = stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
	227	if (ret < 0) {
	228	mutex_unlock(&data->lock);
	229	return -EINVAL;
	230	}
	231	ret = stk8ba50_read_accel(data, chan->address);
	232	if (ret < 0) {
	233	stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
	234	mutex_unlock(&data->lock);
	235	return -EINVAL;
	236	}
	237	*val = sign_extend32(ret >> STK8BA50_DATA_SHIFT, 9);
	238	stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
884ca456 TB	239	mutex_unlock(&data->lock);
	240	return IIO_VAL_INT;
	241	case IIO_CHAN_INFO_SCALE:
	242	*val = 0;
003f4880	243	*val2 = stk8ba50_scale_table[data->range].scale_val;
884ca456	244	return IIO_VAL_INT_PLUS_MICRO;
eb2c9ce2 TB	245	case IIO_CHAN_INFO_SAMP_FREQ:
	246	*val = stk8ba50_samp_freq_table
	247	[data->sample_rate_idx].samp_freq;
	248	*val2 = 0;
	249	return IIO_VAL_INT;
884ca456 TB	250	}
	251
	252	return -EINVAL;
	253	}
	254
	255	static int stk8ba50_write_raw(struct iio_dev *indio_dev,
	256	struct iio_chan_spec const *chan,
	257	int val, int val2, long mask)
	258	{
	259	int ret;
	260	int i;
	261	int index = -1;
	262	struct stk8ba50_data *data = iio_priv(indio_dev);
	263
	264	switch (mask) {
	265	case IIO_CHAN_INFO_SCALE:
	266	if (val != 0)
	267	return -EINVAL;
	268
	269	for (i = 0; i < ARRAY_SIZE(stk8ba50_scale_table); i++)
003f4880	270	if (val2 == stk8ba50_scale_table[i].scale_val) {
884ca456 TB	271	index = i;
	272	break;
	273	}
	274	if (index < 0)
	275	return -EINVAL;
	276
	277	ret = i2c_smbus_write_byte_data(data->client,
	278	STK8BA50_REG_RANGE,
003f4880	279	stk8ba50_scale_table[index].reg_val);
884ca456 TB	280	if (ret < 0)
	281	dev_err(&data->client->dev,
	282	"failed to set measurement range\n");
	283	else
	284	data->range = index;
	285
eb2c9ce2 TB	286	return ret;
	287	case IIO_CHAN_INFO_SAMP_FREQ:
	288	for (i = 0; i < ARRAY_SIZE(stk8ba50_samp_freq_table); i++)
	289	if (val == stk8ba50_samp_freq_table[i].samp_freq) {
	290	index = i;
	291	break;
	292	}
	293	if (index < 0)
	294	return -EINVAL;
	295
	296	ret = i2c_smbus_write_byte_data(data->client,
	297	STK8BA50_REG_BWSEL,
	298	stk8ba50_samp_freq_table[index].reg_val);
	299	if (ret < 0)
	300	dev_err(&data->client->dev,
	301	"failed to set sampling rate\n");
	302	else
	303	data->sample_rate_idx = index;
	304
884ca456 TB	305	return ret;
	306	}
	307
	308	return -EINVAL;
	309	}
	310
	311	static const struct iio_info stk8ba50_info = {
	312	.driver_module = THIS_MODULE,
	313	.read_raw = stk8ba50_read_raw,
	314	.write_raw = stk8ba50_write_raw,
	315	.attrs = &stk8ba50_attribute_group,
	316	};
	317
db6a19b8 TB	318	static irqreturn_t stk8ba50_trigger_handler(int irq, void *p)
	319	{
	320	struct iio_poll_func *pf = p;
	321	struct iio_dev *indio_dev = pf->indio_dev;
	322	struct stk8ba50_data *data = iio_priv(indio_dev);
	323	int bit, ret, i = 0;
	324
	325	mutex_lock(&data->lock);
	326	/*
	327	* Do a bulk read if all channels are requested,
	328	* from 0x02 (XOUT1) to 0x07 (ZOUT2)
	329	*/
	330	if (*(indio_dev->active_scan_mask) == STK8BA50_ALL_CHANNEL_MASK) {
	331	ret = i2c_smbus_read_i2c_block_data(data->client,
	332	STK8BA50_REG_XOUT,
	333	STK8BA50_ALL_CHANNEL_SIZE,
	334	(u8 *)data->buffer);
	335	if (ret < STK8BA50_ALL_CHANNEL_SIZE) {
	336	dev_err(&data->client->dev, "register read failed\n");
	337	goto err;
	338	}
	339	} else {
	340	for_each_set_bit(bit, indio_dev->active_scan_mask,
	341	indio_dev->masklength) {
	342	ret = stk8ba50_read_accel(data,
	343	stk8ba50_channel_table[bit]);
	344	if (ret < 0)
	345	goto err;
	346
	347	data->buffer[i++] = ret;
	348	}
	349	}
	350	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
	351	pf->timestamp);
	352	err:
	353	mutex_unlock(&data->lock);
	354	iio_trigger_notify_done(indio_dev->trig);
	355
	356	return IRQ_HANDLED;
	357	}
	358
	359	static irqreturn_t stk8ba50_data_rdy_trig_poll(int irq, void *private)
	360	{
	361	struct iio_dev *indio_dev = private;
	362	struct stk8ba50_data *data = iio_priv(indio_dev);
	363
	364	if (data->dready_trigger_on)
	365	iio_trigger_poll(data->dready_trig);
	366
	367	return IRQ_HANDLED;
	368	}
	369
	370	static int stk8ba50_buffer_preenable(struct iio_dev *indio_dev)
	371	{
	372	struct stk8ba50_data *data = iio_priv(indio_dev);
	373
	374	return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
	375	}
	376
	377	static int stk8ba50_buffer_postdisable(struct iio_dev *indio_dev)
	378	{
	379	struct stk8ba50_data *data = iio_priv(indio_dev);
	380
	381	return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
382	}
383
384	static const struct iio_buffer_setup_ops stk8ba50_buffer_setup_ops = {
385	.preenable = stk8ba50_buffer_preenable,
386	.postenable = iio_triggered_buffer_postenable,
387	.predisable = iio_triggered_buffer_predisable,
388	.postdisable = stk8ba50_buffer_postdisable,
389	};
390
391	static int stk8ba50_gpio_probe(struct i2c_client *client)
884ca456	392	{
db6a19b8 TB	393	struct device *dev;
db6a19b8 TB	394	struct gpio_desc *gpio;
884ca456	395	int ret;
884ca456	396
db6a19b8 TB	397	if (!client)
db6a19b8 TB	398	return -EINVAL;
884ca456	399
db6a19b8	400	dev = &client->dev;
884ca456	401
db6a19b8 TB	402	/* data ready gpio interrupt pin */
	403	gpio = devm_gpiod_get_index(dev, STK8BA50_GPIO, 0, GPIOD_IN);
	404	if (IS_ERR(gpio)) {
	405	dev_err(dev, "acpi gpio get index failed\n");
	406	return PTR_ERR(gpio);
	407	}
884ca456	408
db6a19b8 TB	409	ret = gpiod_to_irq(gpio);
db6a19b8 TB	410	dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);
884ca456	411
884ca456 TB	412	return ret;
	413	}
	414
	415	static int stk8ba50_probe(struct i2c_client *client,
	416	const struct i2c_device_id *id)
	417	{
	418	int ret;
	419	struct iio_dev *indio_dev;
	420	struct stk8ba50_data *data;
	421
	422	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	423	if (!indio_dev) {
	424	dev_err(&client->dev, "iio allocation failed!\n");
	425	return -ENOMEM;
	426	}
	427
	428	data = iio_priv(indio_dev);
	429	data->client = client;
	430	i2c_set_clientdata(client, indio_dev);
	431	mutex_init(&data->lock);
	432
	433	indio_dev->dev.parent = &client->dev;
	434	indio_dev->info = &stk8ba50_info;
	435	indio_dev->name = STK8BA50_DRIVER_NAME;
	436	indio_dev->modes = INDIO_DIRECT_MODE;
	437	indio_dev->channels = stk8ba50_channels;
	438	indio_dev->num_channels = ARRAY_SIZE(stk8ba50_channels);
	439
	440	/* Reset all registers on startup */
	441	ret = i2c_smbus_write_byte_data(client,
	442	STK8BA50_REG_SWRST, STK8BA50_RESET_CMD);
	443	if (ret < 0) {
	444	dev_err(&client->dev, "failed to reset sensor\n");
db42a9be	445	goto err_power_off;
884ca456 TB	446	}
	447
	448	/* The default range is +/-2g */
	449	data->range = 0;
	450
eb2c9ce2 TB	451	/* The default sampling rate is 1792 Hz (maximum) */
	452	data->sample_rate_idx = STK8BA50_SR_1792HZ_IDX;
	453
db6a19b8 TB	454	/* Set up interrupts */
	455	ret = i2c_smbus_write_byte_data(client,
	456	STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
	457	if (ret < 0) {
	458	dev_err(&client->dev, "failed to set up interrupts\n");
	459	goto err_power_off;
	460	}
	461	ret = i2c_smbus_write_byte_data(client,
	462	STK8BA50_REG_INTMAP2, STK8BA50_DREADY_INT_MAP);
	463	if (ret < 0) {
	464	dev_err(&client->dev, "failed to set up interrupts\n");
	465	goto err_power_off;
	466	}
	467
	468	if (client->irq < 0)
	469	client->irq = stk8ba50_gpio_probe(client);
	470
	471	if (client->irq >= 0) {
	472	ret = devm_request_threaded_irq(&client->dev, client->irq,
	473	stk8ba50_data_rdy_trig_poll,
	474	NULL,
	475	IRQF_TRIGGER_RISING \|
	476	IRQF_ONESHOT,
	477	STK8BA50_IRQ_NAME,
	478	indio_dev);
	479	if (ret < 0) {
	480	dev_err(&client->dev, "request irq %d failed\n",
	481	client->irq);
	482	goto err_power_off;
	483	}
	484
	485	data->dready_trig = devm_iio_trigger_alloc(&client->dev,
	486	"%s-dev%d",
	487	indio_dev->name,
	488	indio_dev->id);
	489	if (!data->dready_trig) {
	490	ret = -ENOMEM;
	491	goto err_power_off;
	492	}
	493
	494	data->dready_trig->dev.parent = &client->dev;
	495	data->dready_trig->ops = &stk8ba50_trigger_ops;
	496	iio_trigger_set_drvdata(data->dready_trig, indio_dev);
	497	ret = iio_trigger_register(data->dready_trig);
	498	if (ret) {
	499	dev_err(&client->dev, "iio trigger register failed\n");
	500	goto err_power_off;
	501	}
	502	}
	503
	504	ret = iio_triggered_buffer_setup(indio_dev,
	505	iio_pollfunc_store_time,
	506	stk8ba50_trigger_handler,
	507	&stk8ba50_buffer_setup_ops);
	508	if (ret < 0) {
	509	dev_err(&client->dev, "iio triggered buffer setup failed\n");
	510	goto err_trigger_unregister;
	511	}
	512
884ca456 TB	513	ret = iio_device_register(indio_dev);
	514	if (ret < 0) {
	515	dev_err(&client->dev, "device_register failed\n");
db6a19b8	516	goto err_buffer_cleanup;
884ca456 TB	517	}
	518
	519	return ret;
db42a9be	520
db6a19b8 TB	521	err_buffer_cleanup:
	522	iio_triggered_buffer_cleanup(indio_dev);
	523	err_trigger_unregister:
	524	if (data->dready_trig)
	525	iio_trigger_unregister(data->dready_trig);
db42a9be TB	526	err_power_off:
	527	stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
	528	return ret;
884ca456 TB	529	}
	530
	531	static int stk8ba50_remove(struct i2c_client *client)
	532	{
	533	struct iio_dev *indio_dev = i2c_get_clientdata(client);
db6a19b8	534	struct stk8ba50_data *data = iio_priv(indio_dev);
884ca456 TB	535
884ca456 TB	536	iio_device_unregister(indio_dev);
db6a19b8 TB	537	iio_triggered_buffer_cleanup(indio_dev);
	538
	539	if (data->dready_trig)
	540	iio_trigger_unregister(data->dready_trig);
884ca456	541
db6a19b8	542	return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
884ca456 TB	543	}
	544
	545	#ifdef CONFIG_PM_SLEEP
	546	static int stk8ba50_suspend(struct device *dev)
	547	{
	548	struct stk8ba50_data *data;
	549
	550	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
	551
	552	return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
	553	}
	554
	555	static int stk8ba50_resume(struct device *dev)
	556	{
	557	struct stk8ba50_data *data;
	558
	559	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
	560
	561	return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
	562	}
	563
	564	static SIMPLE_DEV_PM_OPS(stk8ba50_pm_ops, stk8ba50_suspend, stk8ba50_resume);
	565
	566	#define STK8BA50_PM_OPS (&stk8ba50_pm_ops)
	567	#else
	568	#define STK8BA50_PM_OPS NULL
	569	#endif
	570
	571	static const struct i2c_device_id stk8ba50_i2c_id[] = {
	572	{"stk8ba50", 0},
	573	{}
	574	};
58e446fc	575	MODULE_DEVICE_TABLE(i2c, stk8ba50_i2c_id);
884ca456 TB	576
	577	static const struct acpi_device_id stk8ba50_acpi_id[] = {
	578	{"STK8BA50", 0},
	579	{}
	580	};
	581
	582	MODULE_DEVICE_TABLE(acpi, stk8ba50_acpi_id);
	583
	584	static struct i2c_driver stk8ba50_driver = {
	585	.driver = {
	586	.name = "stk8ba50",
	587	.pm = STK8BA50_PM_OPS,
	588	.acpi_match_table = ACPI_PTR(stk8ba50_acpi_id),
	589	},
	590	.probe = stk8ba50_probe,
	591	.remove = stk8ba50_remove,
	592	.id_table = stk8ba50_i2c_id,
	593	};
	594
	595	module_i2c_driver(stk8ba50_driver);
	596
	597	MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
	598	MODULE_DESCRIPTION("STK8BA50 3-Axis Accelerometer driver");
	599	MODULE_LICENSE("GPL v2");