drivers: sensor: ams_iAQcore: Implemented ASM Indoor Air Quality Sensor

Implementation of AMS (Austria Micro Systems) Indoor Air Quality Sensor

Signed-off-by: Alexander Wachter <alexander.wachter@student.tugraz.at>

drivers/sensor/CMakeLists.txt

@@ -5,6 +5,7 @@ add_subdirectory_ifdef(CONFIG_ADXL362		adxl362)
 add_subdirectory_ifdef(CONFIG_ADXL372		adxl372)
 add_subdirectory_ifdef(CONFIG_AK8975		ak8975)
 add_subdirectory_ifdef(CONFIG_AMG88XX		amg88xx)
+add_subdirectory_ifdef(CONFIG_AMS_IAQ_CORE	ams_iAQcore)
 add_subdirectory_ifdef(CONFIG_APDS9960		apds9960)
 add_subdirectory_ifdef(CONFIG_BMA280		bma280)
 add_subdirectory_ifdef(CONFIG_BMC150_MAGN	bmc150_magn)

drivers/sensor/Kconfig

@@ -35,6 +35,8 @@ source "drivers/sensor/ak8975/Kconfig"
 
 source "drivers/sensor/amg88xx/Kconfig"
 
+source "drivers/sensor/ams_iAQcore/Kconfig"
+
 source "drivers/sensor/apds9960/Kconfig"
 
 source "drivers/sensor/bma280/Kconfig"

drivers/sensor/ams_iAQcore/CMakeLists.txt

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: Apache-2.0
+
+zephyr_library()
+
+zephyr_library_sources_ifdef(CONFIG_AMS_IAQ_CORE iAQcore.c)

drivers/sensor/ams_iAQcore/Kconfig

@@ -0,0 +1,23 @@
+# Kconfig - iAQ-core Digital VOC sensor configuration options
+
+#
+# Copyright (c) 2018 Alexander Wachter
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+menuconfig AMS_IAQ_CORE
+	bool "iAQ-core Digital VOC sensor"
+	depends on I2C && HAS_DTS_I2C
+	help
+	  Enable driver for iAQ-core Digital VOC sensor.
+
+if AMS_IAQ_CORE
+
+config IAQ_CORE_MAX_READ_RETRIES
+	int "Number of read retries"
+	default 4
+	help
+	 Number of retries when reading failed or device not ready.
+
+endif # AMS_IAQ_CORE

drivers/sensor/ams_iAQcore/iAQcore.c

@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2018 Alexander Wachter.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <device.h>
+#include <i2c.h>
+#include <kernel.h>
+#include <misc/byteorder.h>
+#include <misc/util.h>
+#include <sensor.h>
+#include <misc/__assert.h>
+#include <logging/log.h>
+
+#include "iAQcore.h"
+
+#define LOG_LEVEL CONFIG_SENSOR_LOG_LEVEL
+LOG_MODULE_REGISTER(IAQ_CORE);
+
+static int iaqcore_sample_fetch(struct device *dev, enum sensor_channel chan)
+{
+	struct iaq_core_data *drv_data = dev->driver_data;
+	struct iaq_registers buf;
+	struct i2c_msg msg;
+	int ret, tries;
+
+	__ASSERT_NO_MSG(chan == SENSOR_CHAN_ALL);
+
+	msg.buf = (u8_t *)&buf;
+	msg.len = sizeof(struct iaq_registers);
+	msg.flags = I2C_MSG_READ | I2C_MSG_STOP;
+
+	for (tries = 0; tries < CONFIG_IAQ_CORE_MAX_READ_RETRIES; tries++) {
+
+		ret = i2c_transfer(drv_data->i2c, &msg, 1,
+				   DT_AMS_IAQCORE_0_BASE_ADDRESS);
+		if (ret < 0) {
+			LOG_ERR("Failed to read registers data [%d].", ret);
+			return -EIO;
+		}
+
+		drv_data->status = buf.status;
+
+		if (buf.status == 0x00) {
+			drv_data->co2 = sys_be16_to_cpu(buf.co2_pred);
+			drv_data->voc = sys_be16_to_cpu(buf.voc);
+			drv_data->status = buf.status;
+			drv_data->resistance = sys_be32_to_cpu(buf.resistance);
+
+			return 0;
+		}
+
+		k_sleep(100);
+	}
+
+	if (drv_data->status == 0x01) {
+		LOG_INF("Sensor data not available");
+	}
+
+	if (drv_data->status == 0x80) {
+		LOG_ERR("Sensor Error");
+	}
+
+	return -EIO;
+}
+
+static int iaqcore_channel_get(struct device *dev,
+			       enum sensor_channel chan,
+			       struct sensor_value *val)
+{
+	struct iaq_core_data *drv_data = dev->driver_data;
+
+	switch (chan) {
+	case SENSOR_CHAN_CO2:
+		val->val1 = drv_data->co2;
+		val->val2 = 0;
+		break;
+	case SENSOR_CHAN_VOC:
+		val->val1 = drv_data->voc;
+		val->val2 = 0;
+		break;
+	case SENSOR_CHAN_RESISTANCE:
+		val->val1 = drv_data->resistance;
+		val->val2 = 0;
+		break;
+	default:
+		return -ENOTSUP;
+	}
+
+	return 0;
+}
+
+static const struct sensor_driver_api iaq_core_driver_api = {
+	.sample_fetch = iaqcore_sample_fetch,
+	.channel_get = iaqcore_channel_get,
+};
+
+static int iaq_core_init(struct device *dev)
+{
+	struct iaq_core_data *drv_data = dev->driver_data;
+
+	drv_data->i2c = device_get_binding(DT_AMS_IAQCORE_0_BUS_NAME);
+	if (drv_data->i2c == NULL) {
+		LOG_ERR("Failed to get pointer to %s device!",
+			    DT_AMS_IAQCORE_0_BUS_NAME);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static struct iaq_core_data iaq_core_driver;
+
+DEVICE_AND_API_INIT(iaq_core, DT_AMS_IAQCORE_0_LABEL, iaq_core_init,
+		    &iaq_core_driver, NULL, POST_KERNEL,
+		    CONFIG_SENSOR_INIT_PRIORITY, &iaq_core_driver_api);

drivers/sensor/ams_iAQcore/iAQcore.h

@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2018 Alexander Wachter
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef ZEPHYR_DRIVERS_SENSOR_AMS_IAQCORE_IAQCORE_H_
+#define ZEPHYR_DRIVERS_SENSOR_AMS_IAQCORE_IAQCORE_H_
+
+#include <device.h>
+#include <misc/util.h>
+
+struct iaq_registers {
+	u16_t co2_pred;
+	u8_t  status;
+	s32_t resistance;
+	u16_t voc;
+} __packed;
+
+struct iaq_core_data {
+	struct device *i2c;
+	u16_t co2;
+	u16_t voc;
+	u8_t status;
+	s32_t resistance;
+};
+
+#endif /* ZEPHYR_DRIVERS_SENSOR_AMS_IAQCORE_IAQCORE_H_ */

dts/bindings/sensor/ams,iaqcore.yaml

@@ -0,0 +1,21 @@
+#
+# Copyright (c) 2018, Alexander Wachter
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+---
+title: AMS (Austria Mikro Systeme) Indoor Air Quality Sensor iAQ-core
+version: 0.1
+
+description: >
+    This binding gives a base representation of iAQ-core indoor air quality
+    sensor
+
+inherits:
+    !include i2c-device.yaml
+
+properties:
+    compatible:
+      constraint: "ams,iaqcore"
+
+...

include/sensor.h

@@ -119,6 +119,8 @@ enum sensor_channel {
 	SENSOR_CHAN_VOLTAGE,
 	/** Current, in amps **/
 	SENSOR_CHAN_CURRENT,
+	/** Resistance , in Ohm **/
+	SENSOR_CHAN_RESISTANCE,
 
 	/** Angular rotation, in degrees */
 	SENSOR_CHAN_ROTATION,