[linux-2.6-block.git] / drivers / iio / chemical / vz89x.c

/*
 * vz89x.c - Support for SGX Sensortech MiCS VZ89X VOC sensors
 *
 * Copyright (C) 2015 Matt Ranostay <mranostay@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 */

#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/of.h>
#include <linux/of_device.h>

#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>

#define VZ89X_REG_MEASUREMENT		0x09
#define VZ89X_REG_MEASUREMENT_RD_SIZE	6
#define VZ89X_REG_MEASUREMENT_WR_SIZE	3

#define VZ89X_VOC_CO2_IDX		0
#define VZ89X_VOC_SHORT_IDX		1
#define VZ89X_VOC_TVOC_IDX		2
#define VZ89X_VOC_RESISTANCE_IDX	3

#define VZ89TE_REG_MEASUREMENT		0x0c
#define VZ89TE_REG_MEASUREMENT_RD_SIZE	7
#define VZ89TE_REG_MEASUREMENT_WR_SIZE	6

#define VZ89TE_VOC_TVOC_IDX		0
#define VZ89TE_VOC_CO2_IDX		1
#define VZ89TE_VOC_RESISTANCE_IDX	2

enum {
	VZ89X,
	VZ89TE,
};

struct vz89x_chip_data;

struct vz89x_data {
	struct i2c_client *client;
	const struct vz89x_chip_data *chip;
	struct mutex lock;
	int (*xfer)(struct vz89x_data *data, u8 cmd);

	bool is_valid;
	unsigned long last_update;
	u8 buffer[VZ89TE_REG_MEASUREMENT_RD_SIZE];
};

struct vz89x_chip_data {
	bool (*valid)(struct vz89x_data *data);
	const struct iio_chan_spec *channels;
	u8 num_channels;

	u8 cmd;
	u8 read_size;
	u8 write_size;
};

static const struct iio_chan_spec vz89x_channels[] = {
	{
		.type = IIO_CONCENTRATION,
		.channel2 = IIO_MOD_CO2,
		.modified = 1,
		.info_mask_separate =
			BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_RAW),
		.address = VZ89X_VOC_CO2_IDX,
	},
	{
		.type = IIO_CONCENTRATION,
		.channel2 = IIO_MOD_VOC,
		.modified = 1,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
		.address = VZ89X_VOC_SHORT_IDX,
		.extend_name = "short",
	},
	{
		.type = IIO_CONCENTRATION,
		.channel2 = IIO_MOD_VOC,
		.modified = 1,
		.info_mask_separate =
			BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_RAW),
		.address = VZ89X_VOC_TVOC_IDX,
	},
	{
		.type = IIO_RESISTANCE,
		.info_mask_separate =
			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
		.address = VZ89X_VOC_RESISTANCE_IDX,
		.scan_index = -1,
		.scan_type = {
			.endianness = IIO_LE,
		},
	},
};

static const struct iio_chan_spec vz89te_channels[] = {
	{
		.type = IIO_CONCENTRATION,
		.channel2 = IIO_MOD_VOC,
		.modified = 1,
		.info_mask_separate =
			BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_RAW),
		.address = VZ89TE_VOC_TVOC_IDX,
	},

	{
		.type = IIO_CONCENTRATION,
		.channel2 = IIO_MOD_CO2,
		.modified = 1,
		.info_mask_separate =
			BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_RAW),
		.address = VZ89TE_VOC_CO2_IDX,
	},
	{
		.type = IIO_RESISTANCE,
		.info_mask_separate =
			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
		.address = VZ89TE_VOC_RESISTANCE_IDX,
		.scan_index = -1,
		.scan_type = {
			.endianness = IIO_BE,
		},
	},
};

static IIO_CONST_ATTR(in_concentration_co2_scale, "0.00000698689");
static IIO_CONST_ATTR(in_concentration_voc_scale, "0.00000000436681223");

static struct attribute *vz89x_attributes[] = {
	&iio_const_attr_in_concentration_co2_scale.dev_attr.attr,
	&iio_const_attr_in_concentration_voc_scale.dev_attr.attr,
	NULL,
};

static const struct attribute_group vz89x_attrs_group = {
	.attrs = vz89x_attributes,
};

/*
 * Chipset sometime updates in the middle of a reading causing it to reset the
 * data pointer, and causing invalid reading of previous data.
 * We can check for this by reading MSB of the resistance reading that is
 * always zero, and by also confirming the VOC_short isn't zero.
 */

static bool vz89x_measurement_is_valid(struct vz89x_data *data)
{
	if (data->buffer[VZ89X_VOC_SHORT_IDX] == 0)
		return 1;

	return !!(data->buffer[data->chip->read_size - 1] > 0);
}

/* VZ89TE device has a modified CRC-8 two complement check */
static bool vz89te_measurement_is_valid(struct vz89x_data *data)
{
	u8 crc = 0;
	int i, sum = 0;

	for (i = 0; i < (data->chip->read_size - 1); i++) {
		sum = crc + data->buffer[i];
		crc = sum;
		crc += sum / 256;
	}

	return !((0xff - crc) == data->buffer[data->chip->read_size - 1]);
}

static int vz89x_i2c_xfer(struct vz89x_data *data, u8 cmd)
{
	const struct vz89x_chip_data *chip = data->chip;
	struct i2c_client *client = data->client;
	struct i2c_msg msg[2];
	int ret;
	u8 buf[6] = { cmd, 0, 0, 0, 0, 0xf3 };

	msg[0].addr = client->addr;
	msg[0].flags = client->flags;
	msg[0].len = chip->write_size;
	msg[0].buf  = (char *) &buf;

	msg[1].addr = client->addr;
	msg[1].flags = client->flags | I2C_M_RD;
	msg[1].len = chip->read_size;
	msg[1].buf = (char *) &data->buffer;

	ret = i2c_transfer(client->adapter, msg, 2);

	return (ret == 2) ? 0 : ret;
}

static int vz89x_smbus_xfer(struct vz89x_data *data, u8 cmd)
{
	struct i2c_client *client = data->client;
	int ret;
	int i;

	ret = i2c_smbus_write_word_data(client, cmd, 0);
	if (ret < 0)
		return ret;

	for (i = 0; i < data->chip->read_size; i++) {
		ret = i2c_smbus_read_byte(client);
		if (ret < 0)
			return ret;
		data->buffer[i] = ret;
	}

	return 0;
}

static int vz89x_get_measurement(struct vz89x_data *data)
{
	const struct vz89x_chip_data *chip = data->chip;
	int ret;

	/* sensor can only be polled once a second max per datasheet */
	if (!time_after(jiffies, data->last_update + HZ))
		return data->is_valid ? 0 : -EAGAIN;

	data->is_valid = false;
	data->last_update = jiffies;

	ret = data->xfer(data, chip->cmd);
	if (ret < 0)
		return ret;

	ret = chip->valid(data);
	if (ret)
		return -EAGAIN;

	data->is_valid = true;

	return 0;
}

static int vz89x_get_resistance_reading(struct vz89x_data *data,
					struct iio_chan_spec const *chan,
					int *val)
{
	u8 *tmp = (u8 *) &data->buffer[chan->address];

	switch (chan->scan_type.endianness) {
	case IIO_LE:
		*val = le32_to_cpup((__le32 *) tmp) & GENMASK(23, 0);
		break;
	case IIO_BE:
		*val = be32_to_cpup((__be32 *) tmp) >> 8;
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

static int vz89x_read_raw(struct iio_dev *indio_dev,
			  struct iio_chan_spec const *chan, int *val,
			  int *val2, long mask)
{
	struct vz89x_data *data = iio_priv(indio_dev);
	int ret = -EINVAL;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		mutex_lock(&data->lock);
		ret = vz89x_get_measurement(data);
		mutex_unlock(&data->lock);

		if (ret)
			return ret;

		switch (chan->type) {
		case IIO_CONCENTRATION:
			*val = data->buffer[chan->address];
			return IIO_VAL_INT;
		case IIO_RESISTANCE:
			ret = vz89x_get_resistance_reading(data, chan, val);
			if (!ret)
				return IIO_VAL_INT;
			break;
		default:
			return -EINVAL;
		}
		break;
	case IIO_CHAN_INFO_SCALE:
		switch (chan->type) {
		case IIO_RESISTANCE:
			*val = 10;
			return IIO_VAL_INT;
		default:
			return -EINVAL;
		}
		break;
	case IIO_CHAN_INFO_OFFSET:
		switch (chan->channel2) {
		case IIO_MOD_CO2:
			*val = 44;
			*val2 = 250000;
			return IIO_VAL_INT_PLUS_MICRO;
		case IIO_MOD_VOC:
			*val = -13;
			return IIO_VAL_INT;
		default:
			return -EINVAL;
		}
	}

	return ret;
}

static const struct iio_info vz89x_info = {
	.attrs		= &vz89x_attrs_group,
	.read_raw	= vz89x_read_raw,
	.driver_module	= THIS_MODULE,
};

static const struct vz89x_chip_data vz89x_chips[] = {
	{
		.valid = vz89x_measurement_is_valid,

		.cmd = VZ89X_REG_MEASUREMENT,
		.read_size = VZ89X_REG_MEASUREMENT_RD_SIZE,
		.write_size = VZ89X_REG_MEASUREMENT_WR_SIZE,

		.channels = vz89x_channels,
		.num_channels = ARRAY_SIZE(vz89x_channels),
	},
	{
		.valid = vz89te_measurement_is_valid,

		.cmd = VZ89TE_REG_MEASUREMENT,
		.read_size = VZ89TE_REG_MEASUREMENT_RD_SIZE,
		.write_size = VZ89TE_REG_MEASUREMENT_WR_SIZE,

		.channels = vz89te_channels,
		.num_channels = ARRAY_SIZE(vz89te_channels),
	},
};

static const struct of_device_id vz89x_dt_ids[] = {
	{ .compatible = "sgx,vz89x", .data = (void *) VZ89X },
	{ .compatible = "sgx,vz89te", .data = (void *) VZ89TE },
	{ }
};
MODULE_DEVICE_TABLE(of, vz89x_dt_ids);

static int vz89x_probe(struct i2c_client *client,
		       const struct i2c_device_id *id)
{
	struct iio_dev *indio_dev;
	struct vz89x_data *data;
	const struct of_device_id *of_id;
	int chip_id;

	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	if (!indio_dev)
		return -ENOMEM;
	data = iio_priv(indio_dev);

	if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
		data->xfer = vz89x_i2c_xfer;
	else if (i2c_check_functionality(client->adapter,
				I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BYTE))
		data->xfer = vz89x_smbus_xfer;
	else
		return -EOPNOTSUPP;

	of_id = of_match_device(vz89x_dt_ids, &client->dev);
	if (!of_id)
		chip_id = id->driver_data;
	else
		chip_id = (unsigned long)of_id->data;

	i2c_set_clientdata(client, indio_dev);
	data->client = client;
	data->chip = &vz89x_chips[chip_id];
	data->last_update = jiffies - HZ;
	mutex_init(&data->lock);

	indio_dev->dev.parent = &client->dev;
	indio_dev->info = &vz89x_info,
	indio_dev->name = dev_name(&client->dev);
	indio_dev->modes = INDIO_DIRECT_MODE;

	indio_dev->channels = data->chip->channels;
	indio_dev->num_channels = data->chip->num_channels;

	return devm_iio_device_register(&client->dev, indio_dev);
}

static const struct i2c_device_id vz89x_id[] = {
	{ "vz89x", VZ89X },
	{ "vz89te", VZ89TE },
	{ }
};
MODULE_DEVICE_TABLE(i2c, vz89x_id);

static struct i2c_driver vz89x_driver = {
	.driver = {
		.name	= "vz89x",
		.of_match_table = of_match_ptr(vz89x_dt_ids),
	},
	.probe = vz89x_probe,
	.id_table = vz89x_id,
};
module_i2c_driver(vz89x_driver);

MODULE_AUTHOR("Matt Ranostay <mranostay@gmail.com>");
MODULE_DESCRIPTION("SGX Sensortech MiCS VZ89X VOC sensors");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
cd8d9777 MR	1	/*
	2	* vz89x.c - Support for SGX Sensortech MiCS VZ89X VOC sensors
	3	*
	4	* Copyright (C) 2015 Matt Ranostay <mranostay@gmail.com>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	*/
	17
	18	#include <linux/module.h>
	19	#include <linux/mutex.h>
	20	#include <linux/init.h>
	21	#include <linux/i2c.h>
8376882f MR	22	#include <linux/of.h>
8376882f MR	23	#include <linux/of_device.h>
cd8d9777 MR	24
	25	#include <linux/iio/iio.h>
	26	#include <linux/iio/sysfs.h>
	27
	28	#define VZ89X_REG_MEASUREMENT 0x09
8376882f MR	29	#define VZ89X_REG_MEASUREMENT_RD_SIZE 6
8376882f MR	30	#define VZ89X_REG_MEASUREMENT_WR_SIZE 3
cd8d9777 MR	31
	32	#define VZ89X_VOC_CO2_IDX 0
	33	#define VZ89X_VOC_SHORT_IDX 1
	34	#define VZ89X_VOC_TVOC_IDX 2
	35	#define VZ89X_VOC_RESISTANCE_IDX 3
	36
0a735aa0 MR	37	#define VZ89TE_REG_MEASUREMENT 0x0c
	38	#define VZ89TE_REG_MEASUREMENT_RD_SIZE 7
	39	#define VZ89TE_REG_MEASUREMENT_WR_SIZE 6
	40
	41	#define VZ89TE_VOC_TVOC_IDX 0
	42	#define VZ89TE_VOC_CO2_IDX 1
	43	#define VZ89TE_VOC_RESISTANCE_IDX 2
	44
8376882f MR	45	enum {
8376882f MR	46	VZ89X,
0a735aa0	47	VZ89TE,
8376882f MR	48	};
	49
	50	struct vz89x_chip_data;
	51
cd8d9777 MR	52	struct vz89x_data {
cd8d9777 MR	53	struct i2c_client *client;
8376882f	54	const struct vz89x_chip_data *chip;
cd8d9777	55	struct mutex lock;
93e87d73	56	int (xfer)(struct vz89x_data data, u8 cmd);
cd8d9777	57
9d1894cd	58	bool is_valid;
93e87d73	59	unsigned long last_update;
0a735aa0	60	u8 buffer[VZ89TE_REG_MEASUREMENT_RD_SIZE];
8376882f MR	61	};
	62
	63	struct vz89x_chip_data {
	64	bool (valid)(struct vz89x_data data);
	65	const struct iio_chan_spec *channels;
	66	u8 num_channels;
	67
	68	u8 cmd;
	69	u8 read_size;
	70	u8 write_size;
cd8d9777 MR	71	};
	72
	73	static const struct iio_chan_spec vz89x_channels[] = {
	74	{
	75	.type = IIO_CONCENTRATION,
	76	.channel2 = IIO_MOD_CO2,
	77	.modified = 1,
	78	.info_mask_separate =
	79	BIT(IIO_CHAN_INFO_OFFSET) \| BIT(IIO_CHAN_INFO_RAW),
	80	.address = VZ89X_VOC_CO2_IDX,
	81	},
	82	{
	83	.type = IIO_CONCENTRATION,
	84	.channel2 = IIO_MOD_VOC,
	85	.modified = 1,
	86	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
	87	.address = VZ89X_VOC_SHORT_IDX,
	88	.extend_name = "short",
	89	},
	90	{
	91	.type = IIO_CONCENTRATION,
	92	.channel2 = IIO_MOD_VOC,
	93	.modified = 1,
	94	.info_mask_separate =
	95	BIT(IIO_CHAN_INFO_OFFSET) \| BIT(IIO_CHAN_INFO_RAW),
	96	.address = VZ89X_VOC_TVOC_IDX,
	97	},
	98	{
	99	.type = IIO_RESISTANCE,
	100	.info_mask_separate =
	101	BIT(IIO_CHAN_INFO_RAW) \| BIT(IIO_CHAN_INFO_SCALE),
	102	.address = VZ89X_VOC_RESISTANCE_IDX,
0a735aa0 MR	103	.scan_index = -1,
	104	.scan_type = {
	105	.endianness = IIO_LE,
	106	},
	107	},
	108	};
	109
	110	static const struct iio_chan_spec vz89te_channels[] = {
	111	{
	112	.type = IIO_CONCENTRATION,
	113	.channel2 = IIO_MOD_VOC,
	114	.modified = 1,
	115	.info_mask_separate =
	116	BIT(IIO_CHAN_INFO_OFFSET) \| BIT(IIO_CHAN_INFO_RAW),
	117	.address = VZ89TE_VOC_TVOC_IDX,
	118	},
	119
	120	{
	121	.type = IIO_CONCENTRATION,
	122	.channel2 = IIO_MOD_CO2,
	123	.modified = 1,
	124	.info_mask_separate =
	125	BIT(IIO_CHAN_INFO_OFFSET) \| BIT(IIO_CHAN_INFO_RAW),
	126	.address = VZ89TE_VOC_CO2_IDX,
	127	},
	128	{
	129	.type = IIO_RESISTANCE,
	130	.info_mask_separate =
	131	BIT(IIO_CHAN_INFO_RAW) \| BIT(IIO_CHAN_INFO_SCALE),
	132	.address = VZ89TE_VOC_RESISTANCE_IDX,
	133	.scan_index = -1,
	134	.scan_type = {
	135	.endianness = IIO_BE,
	136	},
cd8d9777 MR	137	},
	138	};
	139
	140	static IIO_CONST_ATTR(in_concentration_co2_scale, "0.00000698689");
	141	static IIO_CONST_ATTR(in_concentration_voc_scale, "0.00000000436681223");
	142
	143	static struct attribute *vz89x_attributes[] = {
	144	&iio_const_attr_in_concentration_co2_scale.dev_attr.attr,
	145	&iio_const_attr_in_concentration_voc_scale.dev_attr.attr,
	146	NULL,
	147	};
	148
	149	static const struct attribute_group vz89x_attrs_group = {
	150	.attrs = vz89x_attributes,
	151	};
	152
bf23cee6 MR	153	/*
	154	* Chipset sometime updates in the middle of a reading causing it to reset the
	155	* data pointer, and causing invalid reading of previous data.
	156	* We can check for this by reading MSB of the resistance reading that is
	157	* always zero, and by also confirming the VOC_short isn't zero.
	158	*/
	159
8376882f	160	static bool vz89x_measurement_is_valid(struct vz89x_data *data)
bf23cee6 MR	161	{
	162	if (data->buffer[VZ89X_VOC_SHORT_IDX] == 0)
	163	return 1;
	164
8376882f	165	return !!(data->buffer[data->chip->read_size - 1] > 0);
bf23cee6 MR	166	}
bf23cee6 MR	167
0a735aa0 MR	168	/* VZ89TE device has a modified CRC-8 two complement check */
	169	static bool vz89te_measurement_is_valid(struct vz89x_data *data)
	170	{
	171	u8 crc = 0;
	172	int i, sum = 0;
	173
	174	for (i = 0; i < (data->chip->read_size - 1); i++) {
	175	sum = crc + data->buffer[i];
	176	crc = sum;
	177	crc += sum / 256;
	178	}
	179
	180	return !((0xff - crc) == data->buffer[data->chip->read_size - 1]);
	181	}
	182
93e87d73	183	static int vz89x_i2c_xfer(struct vz89x_data *data, u8 cmd)
cd8d9777	184	{
8376882f	185	const struct vz89x_chip_data *chip = data->chip;
93e87d73 MR	186	struct i2c_client *client = data->client;
93e87d73 MR	187	struct i2c_msg msg[2];
cd8d9777	188	int ret;
0a735aa0	189	u8 buf[6] = { cmd, 0, 0, 0, 0, 0xf3 };
cd8d9777	190
93e87d73 MR	191	msg[0].addr = client->addr;
93e87d73 MR	192	msg[0].flags = client->flags;
8376882f	193	msg[0].len = chip->write_size;
93e87d73 MR	194	msg[0].buf = (char *) &buf;
	195
	196	msg[1].addr = client->addr;
	197	msg[1].flags = client->flags \| I2C_M_RD;
8376882f	198	msg[1].len = chip->read_size;
93e87d73 MR	199	msg[1].buf = (char *) &data->buffer;
	200
	201	ret = i2c_transfer(client->adapter, msg, 2);
cd8d9777	202
93e87d73 MR	203	return (ret == 2) ? 0 : ret;
	204	}
	205
	206	static int vz89x_smbus_xfer(struct vz89x_data *data, u8 cmd)
	207	{
	208	struct i2c_client *client = data->client;
	209	int ret;
	210	int i;
	211
	212	ret = i2c_smbus_write_word_data(client, cmd, 0);
cd8d9777 MR	213	if (ret < 0)
	214	return ret;
	215
8376882f	216	for (i = 0; i < data->chip->read_size; i++) {
93e87d73	217	ret = i2c_smbus_read_byte(client);
cd8d9777 MR	218	if (ret < 0)
	219	return ret;
	220	data->buffer[i] = ret;
	221	}
	222
93e87d73 MR	223	return 0;
	224	}
	225
	226	static int vz89x_get_measurement(struct vz89x_data *data)
	227	{
8376882f	228	const struct vz89x_chip_data *chip = data->chip;
93e87d73 MR	229	int ret;
	230
	231	/* sensor can only be polled once a second max per datasheet */
	232	if (!time_after(jiffies, data->last_update + HZ))
9d1894cd MR	233	return data->is_valid ? 0 : -EAGAIN;
	234
	235	data->is_valid = false;
	236	data->last_update = jiffies;
93e87d73	237
8376882f	238	ret = data->xfer(data, chip->cmd);
93e87d73 MR	239	if (ret < 0)
	240	return ret;
	241
8376882f	242	ret = chip->valid(data);
bf23cee6 MR	243	if (ret)
	244	return -EAGAIN;
	245
9d1894cd	246	data->is_valid = true;
cd8d9777 MR	247
	248	return 0;
	249	}
	250
0a735aa0 MR	251	static int vz89x_get_resistance_reading(struct vz89x_data *data,
	252	struct iio_chan_spec const *chan,
	253	int *val)
cd8d9777	254	{
0a735aa0	255	u8 tmp = (u8 ) &data->buffer[chan->address];
cd8d9777	256
0a735aa0 MR	257	switch (chan->scan_type.endianness) {
	258	case IIO_LE:
	259	val = le32_to_cpup((__le32 ) tmp) & GENMASK(23, 0);
	260	break;
	261	case IIO_BE:
	262	val = be32_to_cpup((__be32 ) tmp) >> 8;
	263	break;
	264	default:
	265	return -EINVAL;
	266	}
	267
	268	return 0;
cd8d9777 MR	269	}
	270
	271	static int vz89x_read_raw(struct iio_dev *indio_dev,
	272	struct iio_chan_spec const chan, int val,
	273	int *val2, long mask)
	274	{
	275	struct vz89x_data *data = iio_priv(indio_dev);
	276	int ret = -EINVAL;
	277
	278	switch (mask) {
	279	case IIO_CHAN_INFO_RAW:
	280	mutex_lock(&data->lock);
	281	ret = vz89x_get_measurement(data);
	282	mutex_unlock(&data->lock);
	283
	284	if (ret)
	285	return ret;
	286
0a735aa0 MR	287	switch (chan->type) {
0a735aa0 MR	288	case IIO_CONCENTRATION:
cd8d9777 MR	289	*val = data->buffer[chan->address];
cd8d9777 MR	290	return IIO_VAL_INT;
0a735aa0 MR	291	case IIO_RESISTANCE:
	292	ret = vz89x_get_resistance_reading(data, chan, val);
	293	if (!ret)
	294	return IIO_VAL_INT;
	295	break;
cd8d9777 MR	296	default:
	297	return -EINVAL;
	298	}
	299	break;
	300	case IIO_CHAN_INFO_SCALE:
	301	switch (chan->type) {
	302	case IIO_RESISTANCE:
	303	*val = 10;
	304	return IIO_VAL_INT;
	305	default:
	306	return -EINVAL;
	307	}
	308	break;
	309	case IIO_CHAN_INFO_OFFSET:
0a735aa0 MR	310	switch (chan->channel2) {
0a735aa0 MR	311	case IIO_MOD_CO2:
cd8d9777 MR	312	*val = 44;
	313	*val2 = 250000;
	314	return IIO_VAL_INT_PLUS_MICRO;
0a735aa0	315	case IIO_MOD_VOC:
cd8d9777 MR	316	*val = -13;
	317	return IIO_VAL_INT;
	318	default:
	319	return -EINVAL;
	320	}
	321	}
	322
	323	return ret;
	324	}
	325
	326	static const struct iio_info vz89x_info = {
	327	.attrs = &vz89x_attrs_group,
	328	.read_raw = vz89x_read_raw,
	329	.driver_module = THIS_MODULE,
	330	};
	331
8376882f MR	332	static const struct vz89x_chip_data vz89x_chips[] = {
	333	{
	334	.valid = vz89x_measurement_is_valid,
	335
	336	.cmd = VZ89X_REG_MEASUREMENT,
	337	.read_size = VZ89X_REG_MEASUREMENT_RD_SIZE,
	338	.write_size = VZ89X_REG_MEASUREMENT_WR_SIZE,
	339
	340	.channels = vz89x_channels,
	341	.num_channels = ARRAY_SIZE(vz89x_channels),
	342	},
0a735aa0 MR	343	{
	344	.valid = vz89te_measurement_is_valid,
	345
	346	.cmd = VZ89TE_REG_MEASUREMENT,
	347	.read_size = VZ89TE_REG_MEASUREMENT_RD_SIZE,
	348	.write_size = VZ89TE_REG_MEASUREMENT_WR_SIZE,
	349
	350	.channels = vz89te_channels,
	351	.num_channels = ARRAY_SIZE(vz89te_channels),
	352	},
8376882f MR	353	};
	354
	355	static const struct of_device_id vz89x_dt_ids[] = {
	356	{ .compatible = "sgx,vz89x", .data = (void *) VZ89X },
0a735aa0	357	{ .compatible = "sgx,vz89te", .data = (void *) VZ89TE },
8376882f MR	358	{ }
	359	};
	360	MODULE_DEVICE_TABLE(of, vz89x_dt_ids);
	361
cd8d9777 MR	362	static int vz89x_probe(struct i2c_client *client,
	363	const struct i2c_device_id *id)
	364	{
	365	struct iio_dev *indio_dev;
	366	struct vz89x_data *data;
8376882f MR	367	const struct of_device_id *of_id;
8376882f MR	368	int chip_id;
cd8d9777	369
cd8d9777 MR	370	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	371	if (!indio_dev)
	372	return -ENOMEM;
cd8d9777	373	data = iio_priv(indio_dev);
93e87d73 MR	374
	375	if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
	376	data->xfer = vz89x_i2c_xfer;
	377	else if (i2c_check_functionality(client->adapter,
	378	I2C_FUNC_SMBUS_WORD_DATA \| I2C_FUNC_SMBUS_BYTE))
	379	data->xfer = vz89x_smbus_xfer;
	380	else
f8d9d3b4	381	return -EOPNOTSUPP;
93e87d73	382
8376882f MR	383	of_id = of_match_device(vz89x_dt_ids, &client->dev);
	384	if (!of_id)
	385	chip_id = id->driver_data;
	386	else
	387	chip_id = (unsigned long)of_id->data;
	388
cd8d9777 MR	389	i2c_set_clientdata(client, indio_dev);
cd8d9777 MR	390	data->client = client;
8376882f	391	data->chip = &vz89x_chips[chip_id];
cd8d9777 MR	392	data->last_update = jiffies - HZ;
	393	mutex_init(&data->lock);
	394
	395	indio_dev->dev.parent = &client->dev;
	396	indio_dev->info = &vz89x_info,
	397	indio_dev->name = dev_name(&client->dev);
	398	indio_dev->modes = INDIO_DIRECT_MODE;
	399
8376882f MR	400	indio_dev->channels = data->chip->channels;
8376882f MR	401	indio_dev->num_channels = data->chip->num_channels;
cd8d9777 MR	402
	403	return devm_iio_device_register(&client->dev, indio_dev);
	404	}
	405
	406	static const struct i2c_device_id vz89x_id[] = {
8376882f	407	{ "vz89x", VZ89X },
0a735aa0	408	{ "vz89te", VZ89TE },
cd8d9777 MR	409	{ }
	410	};
	411	MODULE_DEVICE_TABLE(i2c, vz89x_id);
	412
cd8d9777 MR	413	static struct i2c_driver vz89x_driver = {
	414	.driver = {
	415	.name = "vz89x",
	416	.of_match_table = of_match_ptr(vz89x_dt_ids),
	417	},
	418	.probe = vz89x_probe,
	419	.id_table = vz89x_id,
	420	};
	421	module_i2c_driver(vz89x_driver);
	422
	423	MODULE_AUTHOR("Matt Ranostay <mranostay@gmail.com>");
	424	MODULE_DESCRIPTION("SGX Sensortech MiCS VZ89X VOC sensors");
	425	MODULE_LICENSE("GPL v2");