mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
190 lines
4.2 KiB
190 lines
4.2 KiB
// SPDX-License-Identifier: GPL-2.0+ |
|
/* |
|
* ams-iaq-core.c - Support for AMS iAQ-Core VOC sensors |
|
* |
|
* Copyright (C) 2015, 2018 |
|
* Author: Matt Ranostay <[email protected]> |
|
*/ |
|
|
|
#include <linux/module.h> |
|
#include <linux/mod_devicetable.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_PROCESSED), |
|
.address = AMS_IAQCORE_VOC_CO2_IDX, |
|
}, |
|
{ |
|
.type = IIO_RESISTANCE, |
|
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), |
|
.address = AMS_IAQCORE_VOC_RESISTANCE_IDX, |
|
}, |
|
{ |
|
.type = IIO_CONCENTRATION, |
|
.channel2 = IIO_MOD_VOC, |
|
.modified = 1, |
|
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), |
|
.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; |
|
|
|
if (mask != IIO_CHAN_INFO_PROCESSED) |
|
return -EINVAL; |
|
|
|
mutex_lock(&data->lock); |
|
ret = ams_iaqcore_get_measurement(data); |
|
|
|
if (ret) |
|
goto err_out; |
|
|
|
switch (chan->address) { |
|
case AMS_IAQCORE_VOC_CO2_IDX: |
|
*val = 0; |
|
*val2 = be16_to_cpu(data->buffer.co2_ppm); |
|
ret = IIO_VAL_INT_PLUS_MICRO; |
|
break; |
|
case AMS_IAQCORE_VOC_RESISTANCE_IDX: |
|
*val = be32_to_cpu(data->buffer.resistance); |
|
ret = IIO_VAL_INT; |
|
break; |
|
case AMS_IAQCORE_VOC_TVOC_IDX: |
|
*val = 0; |
|
*val2 = be16_to_cpu(data->buffer.voc_ppb); |
|
ret = IIO_VAL_INT_PLUS_NANO; |
|
break; |
|
default: |
|
ret = -EINVAL; |
|
} |
|
|
|
err_out: |
|
mutex_unlock(&data->lock); |
|
|
|
return ret; |
|
} |
|
|
|
static const struct iio_info ams_iaqcore_info = { |
|
.read_raw = ams_iaqcore_read_raw, |
|
}; |
|
|
|
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; |
|
|
|
/* so initial reading will complete */ |
|
data->last_update = jiffies - HZ; |
|
mutex_init(&data->lock); |
|
|
|
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 = ams_iaqcore_dt_ids, |
|
}, |
|
.probe = ams_iaqcore_probe, |
|
.id_table = ams_iaqcore_id, |
|
}; |
|
module_i2c_driver(ams_iaqcore_driver); |
|
|
|
MODULE_AUTHOR("Matt Ranostay <[email protected]>"); |
|
MODULE_DESCRIPTION("AMS iAQ-Core VOC sensors"); |
|
MODULE_LICENSE("GPL v2");
|
|
|