Thinking this over do we needed a IIO_CHAN_INFO_PROCESSED_OFFSET to signal that it needs to be after the (value - offset) * scale calculation? Thanks, Matt On Sun, Sep 6, 2015 at 9:20 PM, Matt Ranostay <mranostay@xxxxxxxxx> wrote: > Also one thing to note here is calculation is ((value - 13) * scale)) > + offset versus the normal (value + offset) * scale.. Not sure the > best way to handle this possibly could be.. > > Thanks, > > Matt > > On Sun, Sep 6, 2015 at 8:13 PM, George McCollister > <george.mccollister@xxxxxxxxx> wrote: >> >> >> On Sun, Sep 6, 2015 at 9:39 PM, Matt Ranostay <mranostay@xxxxxxxxx> wrote: >>> >>> Add support for VZ89X sensors VOC and CO2 reporting channels in >>> percentage which can be converted to part per million. >>> >>> Signed-off-by: Matt Ranostay <mranostay@xxxxxxxxx> >>> --- >>> .../ABI/testing/sysfs-bus-iio-chemical-vz89x | 30 +++ >>> .../devicetree/bindings/i2c/trivial-devices.txt | 1 + >>> drivers/iio/Kconfig | 1 + >>> drivers/iio/Makefile | 1 + >>> drivers/iio/chemical/Makefile | 6 + >>> drivers/iio/chemical/vz89x.c | 236 >>> +++++++++++++++++++++ >>> 6 files changed, 275 insertions(+) >>> create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-chemical-vz89x >>> 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..74f2a35 >>> --- /dev/null >>> +++ b/Documentation/ABI/testing/sysfs-bus-iio-chemical-vz89x >>> @@ -0,0 +1,30 @@ >>> +What: /sys/bus/iio/devices/iio:deviceX/in_concentration_CO2_raw >>> +Date: September 2015 >>> +KernelVersion: 4.3 >>> +Contact: Matt Ranostay <mranostay@xxxxxxxxx> >>> +Description: >>> + Get the unscaled, and no offset applied CO2 gas percentage >>> + value. >>> + >>> +What: >>> /sys/bus/iio/devices/iio:deviceX/in_concentration_VOC_short_raw >>> +Date: September 2015 >>> +KernelVersion: 4.3 >>> +Contact: Matt Ranostay <mranostay@xxxxxxxxx> >>> +Description: >>> + Get the raw calibration VOC value from the sensor. >>> + This value has little application outside of calibration. >>> + >>> +What: /sys/bus/iio/devices/iio:deviceX/in_concentration_tVOC_raw >>> +Date: September 2015 >>> +KernelVersion: 4.3 >>> +Contact: Matt Ranostay <mranostay@xxxxxxxxx> >>> +Description: >>> + Get the unscaled, and no offset applied total VOC gas >>> + percentage value. >>> + >>> +What: /sys/bus/iio/devices/iio:deviceX/in_resistance_raw >>> +Date: September 2015 >>> +KernelVersion: 4.3 >>> +Contact: Matt Ranostay <mranostay@xxxxxxxxx> >>> +Description: >>> + Get the unscaled sensor resistance value. >>> 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-$(CONFIG_IIO_KFIFO_BUF) += kfifo_buf.o >>> obj-y += accel/ >>> obj-y += adc/ >>> obj-y += amplifiers/ >>> +obj-y += chemical/ >>> obj-y += common/ >>> obj-y += dac/ >>> obj-y += gyro/ >>> diff --git a/drivers/iio/chemical/Makefile b/drivers/iio/chemical/Makefile >>> new file mode 100644 >>> index 0000000..7292f2d >>> --- /dev/null >>> +++ b/drivers/iio/chemical/Makefile >>> @@ -0,0 +1,6 @@ >>> +# >>> +# Makefile for IIO chemical sensors >>> +# >>> + >>> +# When adding new entries keep the list in alphabetical order >>> +obj-$(CONFIG_VZ89X) += vz89x.o >>> diff --git a/drivers/iio/chemical/vz89x.c b/drivers/iio/chemical/vz89x.c >>> new file mode 100644 >>> index 0000000..ac381cc >>> --- /dev/null >>> +++ b/drivers/iio/chemical/vz89x.c >>> @@ -0,0 +1,236 @@ >>> +/* >>> + * vz89x.c - Support for SGX Sensortech MiCS VZ89X VOC sensors >>> + * >>> + * Copyright (C) 2015 Matt Ranostay <mranostay@xxxxxxxxx> >>> + * >>> + * 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, >>> + .info_mask_separate = BIT(IIO_CHAN_INFO_OFFSET) | >>> + BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), >>> + .address = VZ89X_VOC_CO2_IDX, >>> + .extend_name = "CO2", >>> + }, >>> + { >>> + .type = IIO_CONCENTRATION, >>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), >>> + .address = VZ89X_VOC_SHORT_IDX, >>> + .extend_name = "VOC_short", >>> + }, >>> + { >>> + .type = IIO_CONCENTRATION, >>> + .info_mask_separate = >>> + BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), >>> + .address = VZ89X_VOC_TVOC_IDX, >>> + .extend_name = "tVOC", >>> + }, >>> + { >>> + .type = IIO_RESISTANCE, >>> + .info_mask_separate = >>> + BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), >>> + .address = VZ89X_VOC_RESISTANCE_IDX, >>> + }, >>> +}; >>> + >>> +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] | ((u16)buf[1] << 8) | ((u32)buf[2] << 16); >>> +} >>> + >>> +static int vz89x_get_channel_scale(struct iio_chan_spec const *chan, >>> + int *val, int *val2) >>> +{ >>> + switch (chan->address) { >>> + case VZ89X_VOC_CO2_IDX: >>> + *val = 1600; >>> + *val2 = 229; >>> + return IIO_VAL_FRACTIONAL; >>> + case VZ89X_VOC_TVOC_IDX: >>> + *val = 1000; >>> + *val2 = 229; >>> + return IIO_VAL_FRACTIONAL; >>> + } >>> + >>> + return -EINVAL; >>> +} >>> + >>> +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: >>> + *val = 0; >>> + *val2 = data->buffer[chan->address] - 13; >> >> Magic numbers are unlucky. >> >>> >>> + return IIO_VAL_INT_PLUS_MICRO; >>> + case VZ89X_VOC_SHORT_IDX: >>> + *val = data->buffer[chan->address] - 13; >>> + return IIO_VAL_INT; >>> + case VZ89X_VOC_TVOC_IDX: >>> + *val = 0; >>> + *val2 = data->buffer[chan->address] - 13; >>> + return IIO_VAL_INT_PLUS_NANO; >>> + 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; >>> + case IIO_CONCENTRATION: >>> + return vz89x_get_channel_scale(chan, val, val2); >>> + default: >>> + return -EINVAL; >>> + } >>> + break; >>> + case IIO_CHAN_INFO_OFFSET: >>> + *val = 0; >>> + *val2 = 400; >>> + return IIO_VAL_INT_PLUS_MICRO; >>> + } >>> + >>> + return ret; >>> +} >>> + >>> +static const struct iio_info vz89x_info = { >>> + .driver_module = THIS_MODULE, >>> + .read_raw = vz89x_read_raw, >>> +}; >>> + >>> +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@xxxxxxxxx>"); >>> +MODULE_DESCRIPTION("SGX Sensortech MiCS VZ89X VOC sensors"); >>> +MODULE_LICENSE("GPL v2"); >>> -- >>> 1.9.1 >>> >>> -- >>> To unsubscribe from this list: send the line "unsubscribe devicetree" in >>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >> -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html