[PATCH] iio: chemical: add AMS iAQ-core support

[PATCH] iio: chemical: add AMS iAQ-core support

[Matt Ranostay]

Add support for AMS iAQ-core continuous and pulsed VOC sensors.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
---
 .../devicetree/bindings/i2c/trivial-devices.txt    |   1 +
 drivers/iio/chemical/Kconfig                       |   8 +
 drivers/iio/chemical/Makefile                      |   1 +
 drivers/iio/chemical/ams-iaq-core.c                | 190 +++++++++++++++++++++
 4 files changed, 200 insertions(+)
 create mode 100644 drivers/iio/chemical/ams-iaq-core.c

diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
index c50cf13..f6fec95 100644
--- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
+++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
@@ -20,6 +20,7 @@ adi,adt7476		+/-1C TDM Extended Temp Range I.C
 adi,adt7490		+/-1C TDM Extended Temp Range I.C
 adi,adxl345		Three-Axis Digital Accelerometer
 adi,adxl346		Three-Axis Digital Accelerometer (backward-compatibility value "adi,adxl345" must be listed too)
+ams,iaq-core		AMS iAQ-Core VOC Sensor
 at,24c08		i2c serial eeprom  (24cxx)
 atmel,24c00		i2c serial eeprom  (24cxx)
 atmel,24c01		i2c serial eeprom  (24cxx)
diff --git a/drivers/iio/chemical/Kconfig b/drivers/iio/chemical/Kconfig
index 3061b72..f16de61 100644
--- a/drivers/iio/chemical/Kconfig
+++ b/drivers/iio/chemical/Kconfig
@@ -4,6 +4,14 @@
 
 menu "Chemical Sensors"
 
+config IAQCORE
+	tristate "AMS iAQ-Core VOC sensors"
+	depends on I2C
+	help
+	  Say Y here to build I2C interface support for the AMS
+	  iAQ-Core Continuous/Pulsed VOC (Volatile Organic Compounds)
+	  sensors
+
 config VZ89X
 	tristate "SGX Sensortech MiCS VZ89X VOC sensor"
 	depends on I2C
diff --git a/drivers/iio/chemical/Makefile b/drivers/iio/chemical/Makefile
index 7292f2d..167861f 100644
--- a/drivers/iio/chemical/Makefile
+++ b/drivers/iio/chemical/Makefile
@@ -3,4 +3,5 @@
 #
 
 # When adding new entries keep the list in alphabetical order
+obj-$(CONFIG_IAQCORE)		+= ams-iaq-core.o
 obj-$(CONFIG_VZ89X)		+= vz89x.o
diff --git a/drivers/iio/chemical/ams-iaq-core.c b/drivers/iio/chemical/ams-iaq-core.c
new file mode 100644
index 0000000..db9aa39
--- /dev/null
+++ b/drivers/iio/chemical/ams-iaq-core.c
@@ -0,0 +1,190 @@
+/*
+ * ams-iaq-core.c - Support for AMS iAQ-Core 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>
+
+#define AMS_IAQCORE_DATA_SIZE		9
+
+#define AMS_IAQCORE_VOC_CO2_IDX		0
+#define AMS_IAQCORE_VOC_RESISTANCE_IDX	1
+#define AMS_IAQCORE_VOC_TVOC_IDX	2
+
+struct ams_iaqcore_reading {
+	__be16 co2_ppm;
+	u8 status;
+	__be32 resistance;
+	__be16 voc_ppb;
+} __attribute__((__packed__));
+
+struct ams_iaqcore_data {
+	struct i2c_client *client;
+	struct mutex lock;
+	unsigned long last_update;
+
+	struct ams_iaqcore_reading buffer;
+};
+
+static const struct iio_chan_spec ams_iaqcore_channels[] = {
+	{
+		.type = IIO_CONCENTRATION,
+		.channel2 = IIO_MOD_CO2,
+		.modified = 1,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.address = AMS_IAQCORE_VOC_CO2_IDX,
+	},
+	{
+		.type = IIO_RESISTANCE,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.address = AMS_IAQCORE_VOC_RESISTANCE_IDX,
+	},
+	{
+		.type = IIO_CONCENTRATION,
+		.channel2 = IIO_MOD_VOC,
+		.modified = 1,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.address = AMS_IAQCORE_VOC_TVOC_IDX,
+	},
+};
+
+static int ams_iaqcore_read_measurement(struct ams_iaqcore_data *data)
+{
+	struct i2c_client *client = data->client;
+	int ret;
+
+	struct i2c_msg msg[] = {
+		{
+			.addr = client->addr,
+			.flags = client->flags | I2C_M_RD,
+			.len = AMS_IAQCORE_DATA_SIZE,
+			.buf = (char *) &data->buffer,
+		},
+	};
+
+	ret = i2c_transfer(client->adapter, msg, 1);
+
+	return (ret == AMS_IAQCORE_DATA_SIZE) ? 0 : ret;
+}
+
+static int ams_iaqcore_get_measurement(struct ams_iaqcore_data *data)
+{
+	int ret;
+
+	/* sensor can only be polled once a second max per datasheet */
+	if (!time_after(jiffies, data->last_update + HZ))
+		return 0;
+
+	ret = ams_iaqcore_read_measurement(data);
+	if (ret < 0)
+		return ret;
+
+	data->last_update = jiffies;
+
+	return 0;
+}
+
+static int ams_iaqcore_read_raw(struct iio_dev *indio_dev,
+				struct iio_chan_spec const *chan, int *val,
+				int *val2, long mask)
+{
+	struct ams_iaqcore_data *data = iio_priv(indio_dev);
+	int ret = -EINVAL;
+
+	if (mask != IIO_CHAN_INFO_RAW)
+		return -EINVAL;
+
+	mutex_lock(&data->lock);
+	ret = ams_iaqcore_get_measurement(data);
+	mutex_unlock(&data->lock);
+
+	if (ret)
+		return ret;
+
+	switch (chan->address) {
+	case AMS_IAQCORE_VOC_CO2_IDX:
+		*val = be16_to_cpu(data->buffer.co2_ppm);
+		return IIO_VAL_INT;
+	case AMS_IAQCORE_VOC_RESISTANCE_IDX:
+		*val = be32_to_cpu(data->buffer.resistance);
+		return IIO_VAL_INT;
+	case AMS_IAQCORE_VOC_TVOC_IDX:
+		*val = be16_to_cpu(data->buffer.voc_ppb);
+		return IIO_VAL_INT;
+	}
+	return ret;
+}
+
+static const struct iio_info ams_iaqcore_info = {
+	.read_raw	= ams_iaqcore_read_raw,
+	.driver_module	= THIS_MODULE,
+};
+
+static int ams_iaqcore_probe(struct i2c_client *client,
+			     const struct i2c_device_id *id)
+{
+	struct iio_dev *indio_dev;
+	struct ams_iaqcore_data *data;
+
+	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 = &ams_iaqcore_info,
+	indio_dev->name = dev_name(&client->dev);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	indio_dev->channels = ams_iaqcore_channels;
+	indio_dev->num_channels = ARRAY_SIZE(ams_iaqcore_channels);
+
+	return devm_iio_device_register(&client->dev, indio_dev);
+}
+
+static const struct i2c_device_id ams_iaqcore_id[] = {
+	{ "ams-iaq-core", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, ams_iaqcore_id);
+
+static const struct of_device_id ams_iaqcore_dt_ids[] = {
+	{ .compatible = "ams,iaq-core" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ams_iaqcore_dt_ids);
+
+static struct i2c_driver ams_iaqcore_driver = {
+	.driver = {
+		.name	= "ams-iaq-core",
+		.of_match_table = of_match_ptr(ams_iaqcore_dt_ids),
+	},
+	.probe = ams_iaqcore_probe,
+	.id_table = ams_iaqcore_id,
+};
+module_i2c_driver(ams_iaqcore_driver);
+
+MODULE_AUTHOR("Matt Ranostay <mranostay@gmail.com>");
+MODULE_DESCRIPTION("AMS iAQ-Core VOC sensors");
+MODULE_LICENSE("GPL v2");
-- 
1.9.1

Re: [PATCH] iio: chemical: add AMS iAQ-core support

[Jonathan Cameron]

On 01/12/15 03:46, Matt Ranostay wrote:
> Add support for AMS iAQ-core continuous and pulsed VOC sensors.
> 
> Signed-off-by: Matt Ranostay <mranostay@gmail.com>
The only real question that this raises for me is whether returning the
last good value is a good idea if the sensor isn't ready to take a new
one yet...

Otherwise a few bits and bobs inline.
> ---
>  .../devicetree/bindings/i2c/trivial-devices.txt    |   1 +
>  drivers/iio/chemical/Kconfig                       |   8 +
>  drivers/iio/chemical/Makefile                      |   1 +
>  drivers/iio/chemical/ams-iaq-core.c                | 190 +++++++++++++++++++++
>  4 files changed, 200 insertions(+)
>  create mode 100644 drivers/iio/chemical/ams-iaq-core.c
> 
> diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> index c50cf13..f6fec95 100644
> --- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> +++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> @@ -20,6 +20,7 @@ adi,adt7476		+/-1C TDM Extended Temp Range I.C
>  adi,adt7490		+/-1C TDM Extended Temp Range I.C
>  adi,adxl345		Three-Axis Digital Accelerometer
>  adi,adxl346		Three-Axis Digital Accelerometer (backward-compatibility value "adi,adxl345" must be listed too)
> +ams,iaq-core		AMS iAQ-Core VOC Sensor
>  at,24c08		i2c serial eeprom  (24cxx)
>  atmel,24c00		i2c serial eeprom  (24cxx)
>  atmel,24c01		i2c serial eeprom  (24cxx)
> diff --git a/drivers/iio/chemical/Kconfig b/drivers/iio/chemical/Kconfig
> index 3061b72..f16de61 100644
> --- a/drivers/iio/chemical/Kconfig
> +++ b/drivers/iio/chemical/Kconfig
> @@ -4,6 +4,14 @@
>  
>  menu "Chemical Sensors"
>  
> +config IAQCORE
> +	tristate "AMS iAQ-Core VOC sensors"
> +	depends on I2C
> +	help
> +	  Say Y here to build I2C interface support for the AMS
> +	  iAQ-Core Continuous/Pulsed VOC (Volatile Organic Compounds)
> +	  sensors
> +
>  config VZ89X
>  	tristate "SGX Sensortech MiCS VZ89X VOC sensor"
>  	depends on I2C
> diff --git a/drivers/iio/chemical/Makefile b/drivers/iio/chemical/Makefile
> index 7292f2d..167861f 100644
> --- a/drivers/iio/chemical/Makefile
> +++ b/drivers/iio/chemical/Makefile
> @@ -3,4 +3,5 @@
>  #
>  
>  # When adding new entries keep the list in alphabetical order
> +obj-$(CONFIG_IAQCORE)		+= ams-iaq-core.o
>  obj-$(CONFIG_VZ89X)		+= vz89x.o
> diff --git a/drivers/iio/chemical/ams-iaq-core.c b/drivers/iio/chemical/ams-iaq-core.c
> new file mode 100644
> index 0000000..db9aa39
> --- /dev/null
> +++ b/drivers/iio/chemical/ams-iaq-core.c
> @@ -0,0 +1,190 @@
> +/*
> + * ams-iaq-core.c - Support for AMS iAQ-Core 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>
> +
> +#define AMS_IAQCORE_DATA_SIZE		9
> +
> +#define AMS_IAQCORE_VOC_CO2_IDX		0
> +#define AMS_IAQCORE_VOC_RESISTANCE_IDX	1
> +#define AMS_IAQCORE_VOC_TVOC_IDX	2
> +
> +struct ams_iaqcore_reading {
> +	__be16 co2_ppm;
> +	u8 status;
> +	__be32 resistance;
> +	__be16 voc_ppb;
> +} __attribute__((__packed__));
> +
> +struct ams_iaqcore_data {
> +	struct i2c_client *client;
> +	struct mutex lock;
> +	unsigned long last_update;
> +
> +	struct ams_iaqcore_reading buffer;
> +};
> +
> +static const struct iio_chan_spec ams_iaqcore_channels[] = {
> +	{
> +		.type = IIO_CONCENTRATION,
> +		.channel2 = IIO_MOD_CO2,
> +		.modified = 1,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
No info at all on scaling etc?  ppm is mentioned on the
data sheet.
> +		.address = AMS_IAQCORE_VOC_CO2_IDX,
> +	},
> +	{
> +		.type = IIO_RESISTANCE,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
As I read the datahsheet this is in ohms anyway so
IIO_CHAN_INFO_PROCESSED is more appropriate.
> +		.address = AMS_IAQCORE_VOC_RESISTANCE_IDX,
> +	},
> +	{
> +		.type = IIO_CONCENTRATION,
> +		.channel2 = IIO_MOD_VOC,
> +		.modified = 1,
Again datasheet implies you can give this a scaling...
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> +		.address = AMS_IAQCORE_VOC_TVOC_IDX,
> +	},
> +};
> +
> +static int ams_iaqcore_read_measurement(struct ams_iaqcore_data *data)
> +{
> +	struct i2c_client *client = data->client;
> +	int ret;
> +
> +	struct i2c_msg msg[] = {
> +		{
> +			.addr = client->addr,
> +			.flags = client->flags | I2C_M_RD,
> +			.len = AMS_IAQCORE_DATA_SIZE,
> +			.buf = (char *) &data->buffer,
> +		},
Why have an array?  Just drop that and pass &msg into the i2c
transfer call.
> +	};
> +
> +	ret = i2c_transfer(client->adapter, msg, 1);
> +
> +	return (ret == AMS_IAQCORE_DATA_SIZE) ? 0 : ret;
> +}
> +
> +static int ams_iaqcore_get_measurement(struct ams_iaqcore_data *data)
> +{
> +	int ret;
> +
> +	/* sensor can only be polled once a second max per datasheet */
> +	if (!time_after(jiffies, data->last_update + HZ))
> +		return 0;
> +
> +	ret = ams_iaqcore_read_measurement(data);
> +	if (ret < 0)
> +		return ret;
> +
> +	data->last_update = jiffies;
> +
> +	return 0;
> +}
> +
> +static int ams_iaqcore_read_raw(struct iio_dev *indio_dev,
> +				struct iio_chan_spec const *chan, int *val,
> +				int *val2, long mask)
> +{
> +	struct ams_iaqcore_data *data = iio_priv(indio_dev);
> +	int ret = -EINVAL;
> +
> +	if (mask != IIO_CHAN_INFO_RAW)
> +		return -EINVAL;
> +
> +	mutex_lock(&data->lock);
> +	ret = ams_iaqcore_get_measurement(data);
> +	mutex_unlock(&data->lock);
> +
> +	if (ret)
> +		return ret;
> +
> +	switch (chan->address) {
> +	case AMS_IAQCORE_VOC_CO2_IDX:
> +		*val = be16_to_cpu(data->buffer.co2_ppm);
> +		return IIO_VAL_INT;
> +	case AMS_IAQCORE_VOC_RESISTANCE_IDX:
> +		*val = be32_to_cpu(data->buffer.resistance);
> +		return IIO_VAL_INT;
> +	case AMS_IAQCORE_VOC_TVOC_IDX:
> +		*val = be16_to_cpu(data->buffer.voc_ppb);
> +		return IIO_VAL_INT;
> +	}
nitpick of the day - blank line here please :)
> +	return ret;
> +}
> +
> +static const struct iio_info ams_iaqcore_info = {
> +	.read_raw	= ams_iaqcore_read_raw,
> +	.driver_module	= THIS_MODULE,
> +};
> +
> +static int ams_iaqcore_probe(struct i2c_client *client,
> +			     const struct i2c_device_id *id)
> +{
> +	struct iio_dev *indio_dev;
> +	struct ams_iaqcore_data *data;
> +
> +	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;
Would have liked a comment here on why the take one second off...
Fairly obvious though so not that important.

> +	data->last_update = jiffies - HZ;
> +	mutex_init(&data->lock);
> +
> +	indio_dev->dev.parent = &client->dev;
> +	indio_dev->info = &ams_iaqcore_info,
> +	indio_dev->name = dev_name(&client->dev);
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +
> +	indio_dev->channels = ams_iaqcore_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(ams_iaqcore_channels);
> +
> +	return devm_iio_device_register(&client->dev, indio_dev);
> +}
> +
> +static const struct i2c_device_id ams_iaqcore_id[] = {
> +	{ "ams-iaq-core", 0 },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(i2c, ams_iaqcore_id);
> +
> +static const struct of_device_id ams_iaqcore_dt_ids[] = {
> +	{ .compatible = "ams,iaq-core" },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, ams_iaqcore_dt_ids);
> +
> +static struct i2c_driver ams_iaqcore_driver = {
> +	.driver = {
> +		.name	= "ams-iaq-core",
> +		.of_match_table = of_match_ptr(ams_iaqcore_dt_ids),
> +	},
> +	.probe = ams_iaqcore_probe,
> +	.id_table = ams_iaqcore_id,
> +};
> +module_i2c_driver(ams_iaqcore_driver);
> +
> +MODULE_AUTHOR("Matt Ranostay <mranostay@gmail.com>");
> +MODULE_DESCRIPTION("AMS iAQ-Core VOC sensors");
> +MODULE_LICENSE("GPL v2");
> 

Re: [PATCH] iio: chemical: add AMS iAQ-core support

[Matt Ranostay]

On Sat, Dec 5, 2015 at 9:00 AM, Jonathan Cameron <jic23@kernel.org> wrote:
> On 01/12/15 03:46, Matt Ranostay wrote:
>> Add support for AMS iAQ-core continuous and pulsed VOC sensors.
>>
>> Signed-off-by: Matt Ranostay <mranostay@gmail.com>
> The only real question that this raises for me is whether returning the
> last good value is a good idea if the sensor isn't ready to take a new
> one yet...
>
> Otherwise a few bits and bobs inline.
>> ---
>>  .../devicetree/bindings/i2c/trivial-devices.txt    |   1 +
>>  drivers/iio/chemical/Kconfig                       |   8 +
>>  drivers/iio/chemical/Makefile                      |   1 +
>>  drivers/iio/chemical/ams-iaq-core.c                | 190 +++++++++++++++++++++
>>  4 files changed, 200 insertions(+)
>>  create mode 100644 drivers/iio/chemical/ams-iaq-core.c
>>
>> diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
>> index c50cf13..f6fec95 100644
>> --- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
>> +++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
>> @@ -20,6 +20,7 @@ adi,adt7476         +/-1C TDM Extended Temp Range I.C
>>  adi,adt7490          +/-1C TDM Extended Temp Range I.C
>>  adi,adxl345          Three-Axis Digital Accelerometer
>>  adi,adxl346          Three-Axis Digital Accelerometer (backward-compatibility value "adi,adxl345" must be listed too)
>> +ams,iaq-core         AMS iAQ-Core VOC Sensor
>>  at,24c08             i2c serial eeprom  (24cxx)
>>  atmel,24c00          i2c serial eeprom  (24cxx)
>>  atmel,24c01          i2c serial eeprom  (24cxx)
>> diff --git a/drivers/iio/chemical/Kconfig b/drivers/iio/chemical/Kconfig
>> index 3061b72..f16de61 100644
>> --- a/drivers/iio/chemical/Kconfig
>> +++ b/drivers/iio/chemical/Kconfig
>> @@ -4,6 +4,14 @@
>>
>>  menu "Chemical Sensors"
>>
>> +config IAQCORE
>> +     tristate "AMS iAQ-Core VOC sensors"
>> +     depends on I2C
>> +     help
>> +       Say Y here to build I2C interface support for the AMS
>> +       iAQ-Core Continuous/Pulsed VOC (Volatile Organic Compounds)
>> +       sensors
>> +
>>  config VZ89X
>>       tristate "SGX Sensortech MiCS VZ89X VOC sensor"
>>       depends on I2C
>> diff --git a/drivers/iio/chemical/Makefile b/drivers/iio/chemical/Makefile
>> index 7292f2d..167861f 100644
>> --- a/drivers/iio/chemical/Makefile
>> +++ b/drivers/iio/chemical/Makefile
>> @@ -3,4 +3,5 @@
>>  #
>>
>>  # When adding new entries keep the list in alphabetical order
>> +obj-$(CONFIG_IAQCORE)                += ams-iaq-core.o
>>  obj-$(CONFIG_VZ89X)          += vz89x.o
>> diff --git a/drivers/iio/chemical/ams-iaq-core.c b/drivers/iio/chemical/ams-iaq-core.c
>> new file mode 100644
>> index 0000000..db9aa39
>> --- /dev/null
>> +++ b/drivers/iio/chemical/ams-iaq-core.c
>> @@ -0,0 +1,190 @@
>> +/*
>> + * ams-iaq-core.c - Support for AMS iAQ-Core 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>
>> +
>> +#define AMS_IAQCORE_DATA_SIZE                9
>> +
>> +#define AMS_IAQCORE_VOC_CO2_IDX              0
>> +#define AMS_IAQCORE_VOC_RESISTANCE_IDX       1
>> +#define AMS_IAQCORE_VOC_TVOC_IDX     2
>> +
>> +struct ams_iaqcore_reading {
>> +     __be16 co2_ppm;
>> +     u8 status;
>> +     __be32 resistance;
>> +     __be16 voc_ppb;
>> +} __attribute__((__packed__));
>> +
>> +struct ams_iaqcore_data {
>> +     struct i2c_client *client;
>> +     struct mutex lock;
>> +     unsigned long last_update;
>> +
>> +     struct ams_iaqcore_reading buffer;
>> +};
>> +
>> +static const struct iio_chan_spec ams_iaqcore_channels[] = {
>> +     {
>> +             .type = IIO_CONCENTRATION,
>> +             .channel2 = IIO_MOD_CO2,
>> +             .modified = 1,
>> +             .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> No info at all on scaling etc?  ppm is mentioned on the
> data sheet.

D'oh forgot the scaling to convert it to the processed
IIO_CONCENTRATION value. Will fix in v2

>> +             .address = AMS_IAQCORE_VOC_CO2_IDX,
>> +     },
>> +     {
>> +             .type = IIO_RESISTANCE,
>> +             .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> As I read the datahsheet this is in ohms anyway so
> IIO_CHAN_INFO_PROCESSED is more appropriate.
>> +             .address = AMS_IAQCORE_VOC_RESISTANCE_IDX,
>> +     },
>> +     {
>> +             .type = IIO_CONCENTRATION,
>> +             .channel2 = IIO_MOD_VOC,
>> +             .modified = 1,
> Again datasheet implies you can give this a scaling...
>> +             .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
>> +             .address = AMS_IAQCORE_VOC_TVOC_IDX,
>> +     },
>> +};
>> +
>> +static int ams_iaqcore_read_measurement(struct ams_iaqcore_data *data)
>> +{
>> +     struct i2c_client *client = data->client;
>> +     int ret;
>> +
>> +     struct i2c_msg msg[] = {
>> +             {
>> +                     .addr = client->addr,
>> +                     .flags = client->flags | I2C_M_RD,
>> +                     .len = AMS_IAQCORE_DATA_SIZE,
>> +                     .buf = (char *) &data->buffer,
>> +             },
> Why have an array?  Just drop that and pass &msg into the i2c
> transfer call.

Noted.

>> +     };
>> +
>> +     ret = i2c_transfer(client->adapter, msg, 1);
>> +
>> +     return (ret == AMS_IAQCORE_DATA_SIZE) ? 0 : ret;
>> +}
>> +
>> +static int ams_iaqcore_get_measurement(struct ams_iaqcore_data *data)
>> +{
>> +     int ret;
>> +
>> +     /* sensor can only be polled once a second max per datasheet */
>> +     if (!time_after(jiffies, data->last_update + HZ))
>> +             return 0;
>> +
>> +     ret = ams_iaqcore_read_measurement(data);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     data->last_update = jiffies;
>> +
>> +     return 0;
>> +}
>> +
>> +static int ams_iaqcore_read_raw(struct iio_dev *indio_dev,
>> +                             struct iio_chan_spec const *chan, int *val,
>> +                             int *val2, long mask)
>> +{
>> +     struct ams_iaqcore_data *data = iio_priv(indio_dev);
>> +     int ret = -EINVAL;
>> +
>> +     if (mask != IIO_CHAN_INFO_RAW)
>> +             return -EINVAL;
>> +
>> +     mutex_lock(&data->lock);
>> +     ret = ams_iaqcore_get_measurement(data);
>> +     mutex_unlock(&data->lock);
>> +
>> +     if (ret)
>> +             return ret;
>> +
>> +     switch (chan->address) {
>> +     case AMS_IAQCORE_VOC_CO2_IDX:
>> +             *val = be16_to_cpu(data->buffer.co2_ppm);
>> +             return IIO_VAL_INT;
>> +     case AMS_IAQCORE_VOC_RESISTANCE_IDX:
>> +             *val = be32_to_cpu(data->buffer.resistance);
>> +             return IIO_VAL_INT;
>> +     case AMS_IAQCORE_VOC_TVOC_IDX:
>> +             *val = be16_to_cpu(data->buffer.voc_ppb);
>> +             return IIO_VAL_INT;
>> +     }
> nitpick of the day - blank line here please :)
>> +     return ret;
>> +}
>> +
>> +static const struct iio_info ams_iaqcore_info = {
>> +     .read_raw       = ams_iaqcore_read_raw,
>> +     .driver_module  = THIS_MODULE,
>> +};
>> +
>> +static int ams_iaqcore_probe(struct i2c_client *client,
>> +                          const struct i2c_device_id *id)
>> +{
>> +     struct iio_dev *indio_dev;
>> +     struct ams_iaqcore_data *data;
>> +
>> +     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;
> Would have liked a comment here on why the take one second off...
> Fairly obvious though so not that important.

Ah okay will add comment for this.

>
>> +     data->last_update = jiffies - HZ;
>> +     mutex_init(&data->lock);
>> +
>> +     indio_dev->dev.parent = &client->dev;
>> +     indio_dev->info = &ams_iaqcore_info,
>> +     indio_dev->name = dev_name(&client->dev);
>> +     indio_dev->modes = INDIO_DIRECT_MODE;
>> +
>> +     indio_dev->channels = ams_iaqcore_channels;
>> +     indio_dev->num_channels = ARRAY_SIZE(ams_iaqcore_channels);
>> +
>> +     return devm_iio_device_register(&client->dev, indio_dev);
>> +}
>> +
>> +static const struct i2c_device_id ams_iaqcore_id[] = {
>> +     { "ams-iaq-core", 0 },
>> +     { }
>> +};
>> +MODULE_DEVICE_TABLE(i2c, ams_iaqcore_id);
>> +
>> +static const struct of_device_id ams_iaqcore_dt_ids[] = {
>> +     { .compatible = "ams,iaq-core" },
>> +     { }
>> +};
>> +MODULE_DEVICE_TABLE(of, ams_iaqcore_dt_ids);
>> +
>> +static struct i2c_driver ams_iaqcore_driver = {
>> +     .driver = {
>> +             .name   = "ams-iaq-core",
>> +             .of_match_table = of_match_ptr(ams_iaqcore_dt_ids),
>> +     },
>> +     .probe = ams_iaqcore_probe,
>> +     .id_table = ams_iaqcore_id,
>> +};
>> +module_i2c_driver(ams_iaqcore_driver);
>> +
>> +MODULE_AUTHOR("Matt Ranostay <mranostay@gmail.com>");
>> +MODULE_DESCRIPTION("AMS iAQ-Core VOC sensors");
>> +MODULE_LICENSE("GPL v2");
>>
>

Re: [PATCH] iio: chemical: add AMS iAQ-core support

[Peter Meerwald-Stadler]

> Add support for AMS iAQ-core continuous and pulsed VOC sensors.

nitpicking below
 
> Signed-off-by: Matt Ranostay <mranostay@gmail.com>
> ---
>  .../devicetree/bindings/i2c/trivial-devices.txt    |   1 +
>  drivers/iio/chemical/Kconfig                       |   8 +
>  drivers/iio/chemical/Makefile                      |   1 +
>  drivers/iio/chemical/ams-iaq-core.c                | 190 +++++++++++++++++++++
>  4 files changed, 200 insertions(+)
>  create mode 100644 drivers/iio/chemical/ams-iaq-core.c
> 
> diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> index c50cf13..f6fec95 100644
> --- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> +++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> @@ -20,6 +20,7 @@ adi,adt7476		+/-1C TDM Extended Temp Range I.C
>  adi,adt7490		+/-1C TDM Extended Temp Range I.C
>  adi,adxl345		Three-Axis Digital Accelerometer
>  adi,adxl346		Three-Axis Digital Accelerometer (backward-compatibility value "adi,adxl345" must be listed too)
> +ams,iaq-core		AMS iAQ-Core VOC Sensor
>  at,24c08		i2c serial eeprom  (24cxx)
>  atmel,24c00		i2c serial eeprom  (24cxx)
>  atmel,24c01		i2c serial eeprom  (24cxx)
> diff --git a/drivers/iio/chemical/Kconfig b/drivers/iio/chemical/Kconfig
> index 3061b72..f16de61 100644
> --- a/drivers/iio/chemical/Kconfig
> +++ b/drivers/iio/chemical/Kconfig
> @@ -4,6 +4,14 @@
>  
>  menu "Chemical Sensors"
>  
> +config IAQCORE
> +	tristate "AMS iAQ-Core VOC sensors"
> +	depends on I2C
> +	help
> +	  Say Y here to build I2C interface support for the AMS
> +	  iAQ-Core Continuous/Pulsed VOC (Volatile Organic Compounds)
> +	  sensors
> +
>  config VZ89X
>  	tristate "SGX Sensortech MiCS VZ89X VOC sensor"
>  	depends on I2C
> diff --git a/drivers/iio/chemical/Makefile b/drivers/iio/chemical/Makefile
> index 7292f2d..167861f 100644
> --- a/drivers/iio/chemical/Makefile
> +++ b/drivers/iio/chemical/Makefile
> @@ -3,4 +3,5 @@
>  #
>  
>  # When adding new entries keep the list in alphabetical order
> +obj-$(CONFIG_IAQCORE)		+= ams-iaq-core.o
>  obj-$(CONFIG_VZ89X)		+= vz89x.o
> diff --git a/drivers/iio/chemical/ams-iaq-core.c b/drivers/iio/chemical/ams-iaq-core.c
> new file mode 100644
> index 0000000..db9aa39
> --- /dev/null
> +++ b/drivers/iio/chemical/ams-iaq-core.c
> @@ -0,0 +1,190 @@
> +/*
> + * ams-iaq-core.c - Support for AMS iAQ-Core 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>
> +
> +#define AMS_IAQCORE_DATA_SIZE		9
> +
> +#define AMS_IAQCORE_VOC_CO2_IDX		0
> +#define AMS_IAQCORE_VOC_RESISTANCE_IDX	1
> +#define AMS_IAQCORE_VOC_TVOC_IDX	2
> +
> +struct ams_iaqcore_reading {
> +	__be16 co2_ppm;
> +	u8 status;
> +	__be32 resistance;
> +	__be16 voc_ppb;
> +} __attribute__((__packed__));
> +
> +struct ams_iaqcore_data {
> +	struct i2c_client *client;
> +	struct mutex lock;
> +	unsigned long last_update;
> +
> +	struct ams_iaqcore_reading buffer;
> +};
> +
> +static const struct iio_chan_spec ams_iaqcore_channels[] = {
> +	{
> +		.type = IIO_CONCENTRATION,
> +		.channel2 = IIO_MOD_CO2,
> +		.modified = 1,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> +		.address = AMS_IAQCORE_VOC_CO2_IDX,
> +	},
> +	{
> +		.type = IIO_RESISTANCE,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> +		.address = AMS_IAQCORE_VOC_RESISTANCE_IDX,
> +	},
> +	{
> +		.type = IIO_CONCENTRATION,
> +		.channel2 = IIO_MOD_VOC,
> +		.modified = 1,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> +		.address = AMS_IAQCORE_VOC_TVOC_IDX,
> +	},
> +};
> +
> +static int ams_iaqcore_read_measurement(struct ams_iaqcore_data *data)
> +{
> +	struct i2c_client *client = data->client;
> +	int ret;
> +
> +	struct i2c_msg msg[] = {
> +		{
> +			.addr = client->addr,
> +			.flags = client->flags | I2C_M_RD,
> +			.len = AMS_IAQCORE_DATA_SIZE,
> +			.buf = (char *) &data->buffer,
> +		},
> +	};
> +
> +	ret = i2c_transfer(client->adapter, msg, 1);
> +
> +	return (ret == AMS_IAQCORE_DATA_SIZE) ? 0 : ret;
> +}
> +
> +static int ams_iaqcore_get_measurement(struct ams_iaqcore_data *data)
> +{
> +	int ret;
> +
> +	/* sensor can only be polled once a second max per datasheet */
> +	if (!time_after(jiffies, data->last_update + HZ))
> +		return 0;
> +
> +	ret = ams_iaqcore_read_measurement(data);
> +	if (ret < 0)
> +		return ret;
> +
> +	data->last_update = jiffies;
> +
> +	return 0;
> +}
> +
> +static int ams_iaqcore_read_raw(struct iio_dev *indio_dev,
> +				struct iio_chan_spec const *chan, int *val,
> +				int *val2, long mask)
> +{
> +	struct ams_iaqcore_data *data = iio_priv(indio_dev);
> +	int ret = -EINVAL;

no need to init ret

> +
> +	if (mask != IIO_CHAN_INFO_RAW)
> +		return -EINVAL;
> +
> +	mutex_lock(&data->lock);
> +	ret = ams_iaqcore_get_measurement(data);
> +	mutex_unlock(&data->lock);
> +
> +	if (ret)
> +		return ret;
> +
> +	switch (chan->address) {
> +	case AMS_IAQCORE_VOC_CO2_IDX:

data->buffer should be mutex-protected (in theory at least)

> +		*val = be16_to_cpu(data->buffer.co2_ppm);
> +		return IIO_VAL_INT;
> +	case AMS_IAQCORE_VOC_RESISTANCE_IDX:
> +		*val = be32_to_cpu(data->buffer.resistance);
> +		return IIO_VAL_INT;
> +	case AMS_IAQCORE_VOC_TVOC_IDX:
> +		*val = be16_to_cpu(data->buffer.voc_ppb);
> +		return IIO_VAL_INT;
> +	}

> +	return ret;

this should return -EINVAL here not ret

> +}
> +
> +static const struct iio_info ams_iaqcore_info = {
> +	.read_raw	= ams_iaqcore_read_raw,
> +	.driver_module	= THIS_MODULE,
> +};
> +
> +static int ams_iaqcore_probe(struct i2c_client *client,
> +			     const struct i2c_device_id *id)
> +{
> +	struct iio_dev *indio_dev;
> +	struct ams_iaqcore_data *data;
> +
> +	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 = &ams_iaqcore_info,
> +	indio_dev->name = dev_name(&client->dev);
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +
> +	indio_dev->channels = ams_iaqcore_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(ams_iaqcore_channels);
> +
> +	return devm_iio_device_register(&client->dev, indio_dev);
> +}
> +
> +static const struct i2c_device_id ams_iaqcore_id[] = {
> +	{ "ams-iaq-core", 0 },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(i2c, ams_iaqcore_id);
> +
> +static const struct of_device_id ams_iaqcore_dt_ids[] = {
> +	{ .compatible = "ams,iaq-core" },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, ams_iaqcore_dt_ids);
> +
> +static struct i2c_driver ams_iaqcore_driver = {
> +	.driver = {
> +		.name	= "ams-iaq-core",
> +		.of_match_table = of_match_ptr(ams_iaqcore_dt_ids),
> +	},
> +	.probe = ams_iaqcore_probe,
> +	.id_table = ams_iaqcore_id,
> +};
> +module_i2c_driver(ams_iaqcore_driver);
> +
> +MODULE_AUTHOR("Matt Ranostay <mranostay@gmail.com>");
> +MODULE_DESCRIPTION("AMS iAQ-Core VOC sensors");
> +MODULE_LICENSE("GPL v2");
> 

-- 

Peter Meerwald-Stadler
+43-664-2444418 (mobile)