drivers: sensor: Add support for CCS811 Digital Gas Sensor

Add support for AMS CCS811 Digital Gas Sensor for monitoring
indoor air quality. This sensor reports the following parameters:

1. Co2 concentration
2. VOC concentration
3. Sensor voltage
4. Sensor current

This driver only supports polling mode as of now.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
This commit is contained in:
Manivannan Sadhasivam 2018-01-05 08:09:05 -08:00 committed by Anas Nashif
commit 9e88120fdf
7 changed files with 388 additions and 0 deletions

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@ -7,6 +7,7 @@ add_subdirectory_ifdef(CONFIG_BMC150_MAGN bmc150_magn)
add_subdirectory_ifdef(CONFIG_BME280 bme280)
add_subdirectory_ifdef(CONFIG_BMG160 bmg160)
add_subdirectory_ifdef(CONFIG_BMI160 bmi160)
add_subdirectory_ifdef(CONFIG_CCS811 ccs811)
add_subdirectory_ifdef(CONFIG_DHT dht)
add_subdirectory_ifdef(CONFIG_FXAS21002 fxas21002)
add_subdirectory_ifdef(CONFIG_FXOS8700 fxos8700)

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@ -58,6 +58,8 @@ source "drivers/sensor/bmi160/Kconfig"
source "drivers/sensor/bmm150/Kconfig"
source "drivers/sensor/ccs811/Kconfig"
source "drivers/sensor/dht/Kconfig"
source "drivers/sensor/fxas21002/Kconfig"

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@ -0,0 +1 @@
zephyr_sources_ifdef(CONFIG_CCS811 ccs811.c)

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@ -0,0 +1,69 @@
# Kconfig - CCS811 Digital Gas sensor configuration options
#
# Copyright (c) 2018 Linaro Ltd.
#
# SPDX-License-Identifier: Apache-2.0
#
menuconfig CCS811
bool
prompt "CCS811 Digital Gas Sensor"
depends on I2C
default n
help
Enable driver for CCS811 Gas sensors.
config CCS811_NAME
string
prompt "Driver name"
default "CCS811"
depends on CCS811
help
Device name with which the CCS811 sensor is identified.
config CCS811_I2C_ADDR
hex
prompt "I2C address for CCS811 Sensor"
depends on CCS811
range 0x5a 0x5b
default "0x5b"
help
I2C address of the CCS811 sensor.
0x5a: I2C_ADDR connected to GND.
0x5b: I2C_ADDR connected to VDD.
config CCS811_I2C_MASTER_DEV_NAME
string
prompt "I2C master where CCS811 is connected"
depends on CCS811
default "I2C_1"
help
Specify the device name of the I2C master device to which the
CCS811 chip is connected.
config CCS811_GPIO_DEV_NAME
string
prompt "GPIO device"
default "GPIOC"
depends on CCS811
help
The device name of the GPIO device to which the CCS811 WAKE
pin is connected.
config CCS811_GPIO_WAKEUP
bool
prompt "Enable GPIO Wakeup for CCS811"
default n
depends on CCS811
help
Enable GPIO Wakeup support for CCS811
config CCS811_GPIO_WAKEUP_PIN_NUM
int
prompt "GPIO Wakeup pin number"
default 0
depends on CCS811 && CCS811_GPIO_WAKEUP
help
The number of the GPIO pin on which the WAKE pin of CCS811
is connected

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@ -0,0 +1,232 @@
/*
* Copyright (c) 2018 Linaro Ltd.
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <device.h>
#include <gpio.h>
#include <i2c.h>
#include <kernel.h>
#include <misc/byteorder.h>
#include <misc/util.h>
#include <sensor.h>
#include <misc/__assert.h>
#include "ccs811.h"
static int ccs811_sample_fetch(struct device *dev, enum sensor_channel chan)
{
struct ccs811_data *drv_data = dev->driver_data;
int tries = 11;
u16_t buf[4];
u8_t status;
/* Check data ready flag for the measurement interval of 1 seconds */
while (tries-- > 0) {
if (i2c_reg_read_byte(drv_data->i2c, CONFIG_CCS811_I2C_ADDR,
CCS811_REG_STATUS, &status) < 0) {
SYS_LOG_ERR("Failed to read Status register");
return -EIO;
}
if ((status & CCS811_STATUS_DATA_READY) || tries == 0) {
break;
}
k_sleep(100);
}
if (!(status & CCS811_STATUS_DATA_READY)) {
SYS_LOG_ERR("Sensor data not available");
return -EIO;
}
if (i2c_burst_read(drv_data->i2c, CONFIG_CCS811_I2C_ADDR,
CCS811_REG_ALG_RESULT_DATA, (u8_t *)buf, 8) < 0) {
SYS_LOG_ERR("Failed to read conversion data.");
return -EIO;
}
drv_data->co2 = sys_be16_to_cpu(buf[0]);
drv_data->voc = sys_be16_to_cpu(buf[1]);
drv_data->status = buf[2] & 0xff;
drv_data->error = buf[2] >> 8;
drv_data->resistance = sys_be16_to_cpu(buf[3]);
return 0;
}
static int ccs811_channel_get(struct device *dev,
enum sensor_channel chan,
struct sensor_value *val)
{
struct ccs811_data *drv_data = dev->driver_data;
u32_t uval;
switch (chan) {
case SENSOR_CHAN_CO2:
uval = drv_data->co2 * 1000000;
val->val1 = uval / 1000000;
val->val2 = uval % 1000000;
break;
case SENSOR_CHAN_VOC:
uval = drv_data->voc * 1000000;
val->val1 = uval / 1000000;
val->val2 = uval % 1000000;
break;
case SENSOR_CHAN_VOLTAGE:
/*
* Voltage readings are contained in least
* significant 10 bits in volts
*/
uval = (drv_data->resistance & CCS811_VOLTAGE_MASK)
* CCS811_VOLTAGE_SCALE;
val->val1 = uval / 1000000;
val->val2 = uval % 1000000;
break;
case SENSOR_CHAN_CURRENT:
/*
* Current readings are contained in most
* significant 6 bits in microAmps
*/
uval = drv_data->resistance >> 10;
val->val1 = uval / 1000000;
val->val2 = uval % 1000000;
break;
default:
return -ENOTSUP;
}
return 0;
}
static const struct sensor_driver_api ccs811_driver_api = {
.sample_fetch = ccs811_sample_fetch,
.channel_get = ccs811_channel_get,
};
static int switch_to_app_mode(struct device *i2c)
{
u8_t status, buf;
SYS_LOG_DBG("Switching to Application mode...");
if (i2c_reg_read_byte(i2c, CONFIG_CCS811_I2C_ADDR,
CCS811_REG_STATUS, &status) < 0) {
SYS_LOG_ERR("Failed to read Status register");
return -EIO;
}
/* Check for the application firmware */
if (!(status & CCS811_STATUS_APP_VALID)) {
SYS_LOG_ERR("No Application firmware loaded");
return -EINVAL;
}
buf = CCS811_REG_APP_START;
/* Set the device to application mode */
if (i2c_write(i2c, &buf, 1, CONFIG_CCS811_I2C_ADDR) < 0) {
SYS_LOG_ERR("Failed to set Application mode");
return -EIO;
}
if (i2c_reg_read_byte(i2c, CONFIG_CCS811_I2C_ADDR,
CCS811_REG_STATUS, &status) < 0) {
SYS_LOG_ERR("Failed to read Status register");
return -EIO;
}
/* Check for application mode */
if (!(status & CCS811_STATUS_FW_MODE)) {
SYS_LOG_ERR("Failed to start Application firmware");
return -EINVAL;
}
SYS_LOG_DBG("CCS811 Application firmware started!");
return 0;
}
int ccs811_init(struct device *dev)
{
struct ccs811_data *drv_data = dev->driver_data;
int ret;
u8_t hw_id, status;
drv_data->i2c = device_get_binding(CONFIG_CCS811_I2C_MASTER_DEV_NAME);
if (drv_data->i2c == NULL) {
SYS_LOG_ERR("Failed to get pointer to %s device!",
CONFIG_CCS811_I2C_MASTER_DEV_NAME);
return -EINVAL;
}
/*
* Wakeup pin should be pulled low before initiating any I2C transfer.
* If it has been tied to GND by default, skip this part.
*/
#ifdef CONFIG_CCS811_GPIO_WAKEUP
drv_data->gpio = device_get_binding(CONFIG_CCS811_GPIO_DEV_NAME);
if (drv_data->gpio == NULL) {
SYS_LOG_ERR("Failed to get pointer to %s device!",
CONFIG_CCS811_GPIO_DEV_NAME);
return -EINVAL;
}
gpio_pin_configure(drv_data->gpio, CONFIG_CCS811_GPIO_WAKEUP_PIN_NUM,
GPIO_DIR_OUT);
gpio_pin_write(drv_data->gpio, CONFIG_CCS811_GPIO_WAKEUP_PIN_NUM, 0);
k_sleep(1);
#endif
/* Switch device to application mode */
ret = switch_to_app_mode(drv_data->i2c);
if (ret) {
return ret;
}
/* Check Hardware ID */
if (i2c_reg_read_byte(drv_data->i2c, CONFIG_CCS811_I2C_ADDR,
CCS811_REG_HW_ID, &hw_id) < 0) {
SYS_LOG_ERR("Failed to read Hardware ID register");
return -EIO;
}
if (hw_id != CCS881_HW_ID) {
SYS_LOG_ERR("Hardware ID mismatch!");
return -EINVAL;
}
/* Set Measurement mode for 1 second */
if (i2c_reg_write_byte(drv_data->i2c, CONFIG_CCS811_I2C_ADDR,
CCS811_REG_MEAS_MODE,
CCS811_MODE_IAQ_1SEC) < 0) {
SYS_LOG_ERR("Failed to set Measurement mode");
return -EIO;
}
/* Check for error */
if (i2c_reg_read_byte(drv_data->i2c, CONFIG_CCS811_I2C_ADDR,
CCS811_REG_STATUS, &status) < 0) {
SYS_LOG_ERR("Failed to read Status register");
return -EIO;
}
if (status & CCS811_STATUS_ERROR) {
SYS_LOG_ERR("Error occurred during sensor configuration");
return -EINVAL;
}
return 0;
}
static struct ccs811_data ccs811_driver;
DEVICE_AND_API_INIT(ccs811, CONFIG_CCS811_NAME, ccs811_init, &ccs811_driver,
NULL, POST_KERNEL, CONFIG_SENSOR_INIT_PRIORITY,
&ccs811_driver_api);

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@ -0,0 +1,61 @@
/*
* Copyright (c) 2018 Linaro Ltd.
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef _SENSOR_CCS811
#define _SENSOR_CCS811
#include <device.h>
#include <gpio.h>
#include <misc/util.h>
/* Registers */
#define CCS811_REG_STATUS 0x00
#define CCS811_REG_MEAS_MODE 0x01
#define CCS811_REG_ALG_RESULT_DATA 0x02
#define CCS811_REG_RAW_DATA 0x03
#define CCS811_REG_HW_ID 0x20
#define CCS811_REG_HW_VERSION 0x21
#define CCS811_REG_HW_VERSION_MASK 0xF0
#define CCS811_REG_ERR 0xE0
#define CCS811_REG_APP_START 0xF4
#define CCS881_HW_ID 0x81
#define CCS811_HW_VERSION 0x10
/* Status register fields */
#define CCS811_STATUS_ERROR BIT(0)
#define CCS811_STATUS_DATA_READY BIT(3)
#define CCS811_STATUS_APP_VALID BIT(4)
#define CCS811_STATUS_FW_MODE BIT(7)
/* Measurement modes */
#define CCS811_MODE_IDLE 0x00
#define CCS811_MODE_IAQ_1SEC 0x10
#define CCS811_MODE_IAQ_10SEC 0x20
#define CCS811_MODE_IAQ_60SEC 0x30
#define CCS811_MODE_RAW_DATA 0x40
#define CCS811_VOLTAGE_SCALE 1613
#define CCS811_VOLTAGE_MASK 0x3FF
struct ccs811_data {
struct device *i2c;
#ifdef CONFIG_CCS811_GPIO_WAKEUP
struct device *gpio;
#endif
u16_t co2;
u16_t voc;
u8_t status;
u8_t error;
u16_t resistance;
};
#define SYS_LOG_DOMAIN "CCS811"
#define SYS_LOG_LEVEL CONFIG_SYS_LOG_SENSOR_LEVEL
#include <logging/sys_log.h>
#endif /* _SENSOR_CCS811_ */

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@ -0,0 +1,22 @@
#
# Copyright (c) 2018, Linaro Limited
#
# SPDX-License-Identifier: Apache-2.0
#
---
title: AMS (Austria Mikro Systeme) Digital Air Quality Sensor CCS811
id: ams,ccs811
version: 0.1
description: >
This binding gives a base representation of CCS811 digital air quality
sensor
inherits:
!include i2c-device.yaml
properties:
compatible:
constraint: "ams,ccs811"
...