Re: [PATCH v5 4/4] iio: chemical: add SGX VZ89x VOC sensor support

[Jonathan Cameron <jic23@kernel.org>]

On 14/09/15 09:35, Peter Meerwald wrote:
> 
>> Add support for VZ89X sensors VOC and CO2 reporting channels in
>> percentage which can be converted to part per million.
> 
> can you make the proper changes for _CONCENTRATION etc. also for 
> tools/iio/iio_event_monitor.c?
Rather than going through another complete version of this series,
would you mind doing that as a follow up patch?

> 
> and comment below
I've fixed this up as chemical sensors when applying.
>  
>> Signed-off-by: Matt Ranostay <mranostay@gmail.com>
>> ---
>>  .../ABI/testing/sysfs-bus-iio-chemical-vz89x       |   7 +
>>  .../devicetree/bindings/i2c/trivial-devices.txt    |   1 +
>>  drivers/iio/Kconfig                                |   1 +
>>  drivers/iio/Makefile                               |   1 +
>>  drivers/iio/chemical/Kconfig                       |  15 ++
>>  drivers/iio/chemical/Makefile                      |   6 +
>>  drivers/iio/chemical/vz89x.c                       | 237 +++++++++++++++++++++
>>  7 files changed, 268 insertions(+)
>>  create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-chemical-vz89x
>>  create mode 100644 drivers/iio/chemical/Kconfig
>>  create mode 100644 drivers/iio/chemical/Makefile
>>  create mode 100644 drivers/iio/chemical/vz89x.c
>>
>> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-chemical-vz89x b/Documentation/ABI/testing/sysfs-bus-iio-chemical-vz89x
>> new file mode 100644
>> index 0000000..c0c1ea9
>> --- /dev/null
>> +++ b/Documentation/ABI/testing/sysfs-bus-iio-chemical-vz89x
>> @@ -0,0 +1,7 @@
>> +What:		/sys/bus/iio/devices/iio:deviceX/in_concentration_VOC_short_raw
>> +Date:		September 2015
>> +KernelVersion:	4.3
>> +Contact:	Matt Ranostay <mranostay@gmail.com>
>> +Description:
>> +		Get the raw calibration VOC value from the sensor.
>> +		This value has little application outside of calibration.
>> diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
>> index d77d412..a550216 100644
>> --- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
>> +++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
>> @@ -88,6 +88,7 @@ ricoh,rs5c372b		I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
>>  ricoh,rv5c386		I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
>>  ricoh,rv5c387a		I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC
>>  samsung,24ad0xd1	S524AD0XF1 (128K/256K-bit Serial EEPROM for Low Power)
>> +sgx,vz89x		SGX Sensortech VZ89X Sensors
>>  sii,s35390a		2-wire CMOS real-time clock
>>  skyworks,sky81452	Skyworks SKY81452: Six-Channel White LED Driver with Touch Panel Bias Supply
>>  st-micro,24c256		i2c serial eeprom  (24cxx)
>> diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig
>> index 4011eff..9664e9c 100644
>> --- a/drivers/iio/Kconfig
>> +++ b/drivers/iio/Kconfig
>> @@ -61,6 +61,7 @@ config IIO_CONSUMERS_PER_TRIGGER
>>  source "drivers/iio/accel/Kconfig"
>>  source "drivers/iio/adc/Kconfig"
>>  source "drivers/iio/amplifiers/Kconfig"
>> +source "drivers/iio/chemical/Kconfig"
>>  source "drivers/iio/common/Kconfig"
>>  source "drivers/iio/dac/Kconfig"
>>  source "drivers/iio/frequency/Kconfig"
>> diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile
>> index 698afc2..2288684 100644
>> --- a/drivers/iio/Makefile
>> +++ b/drivers/iio/Makefile
>> @@ -14,6 +14,7 @@ obj-$(CONFIG_IIO_KFIFO_BUF) += kfifo_buf.o
>>  obj-y += accel/
>>  obj-y += adc/
>>  obj-y += amplifiers/
>> +obj-y += chemical/
>>  obj-y += common/
>>  obj-y += dac/
>>  obj-y += gyro/
>> diff --git a/drivers/iio/chemical/Kconfig b/drivers/iio/chemical/Kconfig
>> new file mode 100644
>> index 0000000..04906af
>> --- /dev/null
>> +++ b/drivers/iio/chemical/Kconfig
>> @@ -0,0 +1,15 @@
>> +#
>> +# Chemical sensors
>> +#
>> +
>> +menu "Indoor Air Quality sensors"
> 
> the comment above says 'Chemical sensors', the menu item 'Indoor Air 
> Quality sensors' -- I guess an outdoor sensor would fit here as well...
Lets just go with Chemical sensors.
> 
>> +
>> +config VZ89X
>> +	tristate "SGX Sensortech MiCS VZ89X VOC sensor"
>> +	depends on I2C
>> +	help
>> +	  Say Y here to build I2C interface support for the SGX
>> +	  Sensortech MiCS VZ89X VOC (Volatile Organic Compounds)
>> +	  sensors
>> +
>> +endmenu
>> diff --git a/drivers/iio/chemical/Makefile b/drivers/iio/chemical/Makefile
>> new file mode 100644
>> index 0000000..7292f2d
>> --- /dev/null
>> +++ b/drivers/iio/chemical/Makefile
>> @@ -0,0 +1,6 @@
>> +#
>> +# Makefile for IIO chemical sensors
>> +#
>> +
>> +# When adding new entries keep the list in alphabetical order
>> +obj-$(CONFIG_VZ89X)		+= vz89x.o
>> diff --git a/drivers/iio/chemical/vz89x.c b/drivers/iio/chemical/vz89x.c
>> new file mode 100644
>> index 0000000..b454200
>> --- /dev/null
>> +++ b/drivers/iio/chemical/vz89x.c
>> @@ -0,0 +1,237 @@
>> +/*
>> + * 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/iio/iio.h>
>> +#include <linux/iio/sysfs.h>
>> +
>> +#define VZ89X_REG_MEASUREMENT		0x09
>> +#define VZ89X_REG_MEASUREMENT_SIZE	6
>> +
>> +#define VZ89X_VOC_CO2_IDX		0
>> +#define VZ89X_VOC_SHORT_IDX		1
>> +#define VZ89X_VOC_TVOC_IDX		2
>> +#define VZ89X_VOC_RESISTANCE_IDX	3
>> +
>> +struct vz89x_data {
>> +	struct i2c_client *client;
>> +	struct mutex lock;
>> +	unsigned long last_update;
>> +
>> +	u8 buffer[VZ89X_REG_MEASUREMENT_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,
>> +	},
>> +};
>> +
>> +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,
>> +};
>> +
>> +static int vz89x_get_measurement(struct vz89x_data *data)
>> +{
>> +	int ret;
>> +	int i;
>> +
>> +	/* sensor can only be polled once a second max per datasheet */
>> +	if (!time_after(jiffies, data->last_update + HZ))
>> +		return 0;
>> +
>> +	ret = i2c_smbus_write_word_data(data->client,
>> +					VZ89X_REG_MEASUREMENT, 0);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	for (i = 0; i < VZ89X_REG_MEASUREMENT_SIZE; i++) {
>> +		ret = i2c_smbus_read_byte(data->client);
>> +		if (ret < 0)
>> +			return ret;
>> +		data->buffer[i] = ret;
>> +	}
>> +
>> +	data->last_update = jiffies;
>> +
>> +	return 0;
>> +}
>> +
>> +static int vz89x_get_resistance_reading(struct vz89x_data *data)
>> +{
>> +	u8 *buf = &data->buffer[VZ89X_VOC_TVOC_IDX];
>> +
>> +	return buf[0] | (buf[1] << 8) | (buf[2] << 16);
>> +}
>> +
>> +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->address) {
>> +		case VZ89X_VOC_CO2_IDX:
>> +		case VZ89X_VOC_SHORT_IDX:
>> +		case VZ89X_VOC_TVOC_IDX:
>> +			*val = data->buffer[chan->address];
>> +			return IIO_VAL_INT;
>> +		case VZ89X_VOC_RESISTANCE_IDX:
>> +			*val = vz89x_get_resistance_reading(data);
>> +			return IIO_VAL_INT;
>> +		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->address) {
>> +		case VZ89X_VOC_CO2_IDX:
>> +			*val = 44;
>> +			*val2 = 250000;
>> +			return IIO_VAL_INT_PLUS_MICRO;
>> +		case VZ89X_VOC_TVOC_IDX:
>> +			*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 int vz89x_probe(struct i2c_client *client,
>> +		       const struct i2c_device_id *id)
>> +{
>> +	struct iio_dev *indio_dev;
>> +	struct vz89x_data *data;
>> +
>> +	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA |
>> +				     I2C_FUNC_SMBUS_BYTE))
>> +		return -ENODEV;
>> +
>> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
>> +	if (!indio_dev)
>> +		return -ENOMEM;
>> +
>> +	data = iio_priv(indio_dev);
>> +	i2c_set_clientdata(client, indio_dev);
>> +	data->client = client;
>> +	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 = vz89x_channels;
>> +	indio_dev->num_channels = ARRAY_SIZE(vz89x_channels);
>> +
>> +	return devm_iio_device_register(&client->dev, indio_dev);
>> +}
>> +
>> +static const struct i2c_device_id vz89x_id[] = {
>> +	{ "vz89x", 0 },
>> +	{ }
>> +};
>> +MODULE_DEVICE_TABLE(i2c, vz89x_id);
>> +
>> +static const struct of_device_id vz89x_dt_ids[] = {
>> +	{ .compatible = "sgx,vz89x" },
>> +	{ }
>> +};
>> +MODULE_DEVICE_TABLE(of, vz89x_dt_ids);
>> +
>> +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");
>>
>