drivers: sensor: Aosong AGS10 TVOC sensor

Added support for Aosong AGS10 TVOC sensor

Signed-off-by: Balthazar Deliers <bdeliers@bdeliers.com>

drivers/sensor/CMakeLists.txt

@@ -9,6 +9,7 @@ add_subdirectory_ifdef(CONFIG_ADXL345 adxl345)
 add_subdirectory_ifdef(CONFIG_ADXL362 adxl362)
 add_subdirectory_ifdef(CONFIG_ADXL367 adxl367)
 add_subdirectory_ifdef(CONFIG_ADXL372 adxl372)
+add_subdirectory_ifdef(CONFIG_AGS10 ags10)
 add_subdirectory_ifdef(CONFIG_AK8975 ak8975)
 add_subdirectory_ifdef(CONFIG_AKM09918C akm09918c)
 add_subdirectory_ifdef(CONFIG_AMD_SB_TSI amd_sb_tsi)

drivers/sensor/Kconfig

@@ -81,6 +81,7 @@ source "drivers/sensor/adxl345/Kconfig"
 source "drivers/sensor/adxl362/Kconfig"
 source "drivers/sensor/adxl367/Kconfig"
 source "drivers/sensor/adxl372/Kconfig"
+source "drivers/sensor/ags10/Kconfig"
 source "drivers/sensor/ak8975/Kconfig"
 source "drivers/sensor/akm09918c/Kconfig"
 source "drivers/sensor/amd_sb_tsi/Kconfig"

drivers/sensor/ags10/CMakeLists.txt

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: Apache-2.0
+
+
+zephyr_library()
+zephyr_library_sources(ags10.c)

drivers/sensor/ags10/Kconfig

@@ -0,0 +1,12 @@
+# Copyright (c) 2023 Balthazar Deliers
+# SPDX-License-Identifier: Apache-2.0
+
+# AOSONG AGS10 TVOC sensor driver options.
+
+config AGS10
+	bool "AOSONG AGS10 TVOC sensor"
+	default y
+	depends on DT_HAS_AOSONG_AGS10_ENABLED
+	select I2C
+	help
+	  Enable AOSONG AGS10 TVOC sensor driver.

drivers/sensor/ags10/ags10.c

@@ -0,0 +1,134 @@
+/*
+ * Copyright (c) 2023 Balthazar Deliers
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define DT_DRV_COMPAT aosong_ags10
+
+#include <zephyr/drivers/sensor.h>
+#include <zephyr/kernel.h>
+#include <zephyr/logging/log.h>
+#include <zephyr/sys/byteorder.h>
+#include <zephyr/sys/crc.h>
+
+#include "ags10.h"
+
+LOG_MODULE_REGISTER(AGS10, CONFIG_SENSOR_LOG_LEVEL);
+
+#define AGS10_MAX_PAYLOAD_SIZE 5U	/* Payload will be max 4 bytes + CRC (datasheet 3.1) */
+
+static int ags10_read(const struct device *dev, uint8_t cmd, uint8_t *data, uint8_t rx_bytes)
+{
+	if (rx_bytes > AGS10_MAX_PAYLOAD_SIZE) {
+		return -EINVAL;
+	}
+
+	const struct ags10_config *conf = dev->config;
+
+	uint8_t recv_buf[AGS10_MAX_PAYLOAD_SIZE] = {0};
+	int ret = i2c_write_read_dt(&conf->bus, &cmd, sizeof(cmd), &recv_buf, rx_bytes);
+
+	if (ret < 0) {
+		return ret;
+	}
+
+	memcpy(data, recv_buf, rx_bytes);
+
+	return 0;
+}
+
+static int ags10_sample_fetch(const struct device *dev, enum sensor_channel chan)
+{
+	if (chan != SENSOR_CHAN_VOC && chan != SENSOR_CHAN_ALL) {
+		return -ENOTSUP;
+	}
+
+	struct ags10_data *data = dev->data;
+	int ret = -ENOTSUP;
+	uint8_t recv_buf[5] = {0};
+
+	ret = ags10_read(dev, AGS10_CMD_DATA_ACQUISITION, recv_buf, 5);
+
+	if (ret == 0) {
+		/* If CRC is valid and data is valid too */
+		if (crc8(&recv_buf[0], 4, 0x31, 0xFF, false) == recv_buf[4] &&
+		    ((recv_buf[0] & AGS10_MSK_STATUS) == AGS10_REG_STATUS_NRDY_READY)) {
+			data->status = recv_buf[0] & AGS10_MSK_STATUS;
+			data->tvoc_ppb = sys_get_be24(&recv_buf[1]);
+			return 0;
+		}
+
+		LOG_WRN("Bad CRC or data not ready");
+		ret = -EIO;
+	}
+
+	return ret;
+}
+
+static int ags10_channel_get(const struct device *dev, enum sensor_channel chan,
+			     struct sensor_value *val)
+{
+	struct ags10_data *data = dev->data;
+
+	if (chan == SENSOR_CHAN_VOC) {
+		val->val1 = data->tvoc_ppb;
+	} else {
+		return -ENOTSUP;
+	}
+
+	val->val2 = 0;
+
+	return 0;
+}
+
+static int ags10_init(const struct device *dev)
+{
+	const struct ags10_config *conf = dev->config;
+	struct ags10_data *data = dev->data;
+	int ret;
+
+	if (!i2c_is_ready_dt(&conf->bus)) {
+		LOG_ERR("Device not ready");
+		return -ENODEV;
+	}
+
+	/* Set initial data values */
+	data->tvoc_ppb = 0;
+	data->status = 0xFF;
+	data->version = 0;
+
+	/* Read firmware version and check CRC */
+	uint8_t recv_buf[5] = {0};
+
+	ret = ags10_read(dev, AGS10_CMD_READ_VERSION, recv_buf, 5);
+
+	/* Bytes 0 to 2 are reserved, byte 3 is version, byte 4 is CRC */
+	if (ret == 0 && crc8(&recv_buf[0], 4, 0x31, 0xFF, false) == recv_buf[4]) {
+		data->version = recv_buf[3];
+		LOG_DBG("Sensor detected");
+	} else if (ret != 0) {
+		LOG_ERR("No reply from sensor");
+		ret = -ENODEV;
+	} else {
+		LOG_WRN("Bad CRC");
+		ret = -EIO;
+	}
+
+	return ret;
+}
+
+static const struct sensor_driver_api ags10_api = {.sample_fetch = ags10_sample_fetch,
+						   .channel_get = ags10_channel_get};
+
+#define AGS10_INIT(n)                                                                              \
+	static struct ags10_data ags10_data_##n;                                                   \
+                                                                                                   \
+	static const struct ags10_config ags10_config_##n = {                                      \
+		.bus = I2C_DT_SPEC_INST_GET(n),                                                    \
+	};                                                                                         \
+                                                                                                   \
+	SENSOR_DEVICE_DT_INST_DEFINE(n, ags10_init, NULL, &ags10_data_##n, &ags10_config_##n,      \
+				     POST_KERNEL, CONFIG_SENSOR_INIT_PRIORITY, &ags10_api);
+
+DT_INST_FOREACH_STATUS_OKAY(AGS10_INIT)

drivers/sensor/ags10/ags10.h

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2023 Balthazar Deliers
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef ZEPHYR_INCLUDE_DRIVERS_SENSOR_AGS10_H_
+#define ZEPHYR_INCLUDE_DRIVERS_SENSOR_AGS10_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <zephyr/device.h>
+#include <zephyr/drivers/i2c.h>
+
+#define AGS10_CMD_DATA_ACQUISITION       0x00
+#define AGS10_CMD_ZERO_POINT_CALIBRATION 0x01
+#define AGS10_CMD_READ_VERSION           0x11
+#define AGS10_CMD_READ_RESISTANCE        0x20
+#define AGS10_CMD_MODIFY_SLAVE_ADDRESS   0x21
+
+#define AGS10_REG_ZERO_POINT_CALIBRATION_RESET 0xFFFF /* Reset to the factory value */
+#define AGS10_REG_ZERO_POINT_CALIBRATION_SET   0x0000 /* Set sensor resistance to zero-point */
+#define AGS10_REG_STATUS_NRDY_READY            0x00   /* Device is ready */
+#define AGS10_REG_STATUS_CH_PPB                0x00   /* Unit is PPB */
+
+#define AGS10_MSK_STATUS      0x0F
+#define AGS10_MSK_STATUS_NRDY 0x01
+#define AGS10_MSK_STATUS_CH   0x0E
+
+struct ags10_config {
+	struct i2c_dt_spec bus;
+};
+
+struct ags10_data {
+	uint32_t tvoc_ppb;
+	uint8_t status;
+	uint32_t version;
+};
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* ZEPHYR_INCLUDE_DRIVERS_SENSOR_AGS10_H_ */

dts/bindings/sensor/aosong,ags10.yaml

@@ -0,0 +1,10 @@
+# Copyright (c) 2023 Balthazar Deliers
+# SPDX-License-Identifier: Apache-2.0
+
+description: |
+    AOSONG AGS10 a high-performance TVOC Sensor With I2C Interface.
+    See: http://www.aosong.com/en/products-86.html
+
+compatible: "aosong,ags10"
+
+include: [sensor-device.yaml, i2c-device.yaml]

tests/drivers/build_all/sensor/i2c.dtsi

@@ -884,3 +884,8 @@ test_i2c_bma4xx: bma4xx@7d {
 	compatible = "bosch,bma4xx";
 	reg = <0x7d>;
 };
+
+test_i2c_ags10: ags10@7e {
+	compatible = "aosong,ags10";
+	reg = <0x7e>;
+};