Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 415 insertions, 0 deletions

diff --git a/drivers/iio/chemical/vz89x.c b/drivers/iio/chemical/vz89x.c
new file mode 100644
index 000000000..415b39339
--- /dev/null
+++ b/drivers/iio/chemical/vz89x.c
@@ -0,0 +1,415 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * vz89x.c - Support for SGX Sensortech MiCS VZ89X VOC sensors
+ *
+ * Copyright (C) 2015-2018
+ * Author: Matt Ranostay <matt.ranostay@konsulko.com>
+ */
+
+#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 true;
+
+	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,
+};
+
+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 <matt.ranostay@konsulko.com>");
+MODULE_DESCRIPTION("SGX Sensortech MiCS VZ89X VOC sensors");
+MODULE_LICENSE("GPL v2");