samples: sensor: add sample for SHT3XD sensor

Added sample code for Sensirion SHT3XD humidity sensor.

Signed-off-by: Peter A. Bigot <pab@pabigot.com>

samples/sensor/sht3xd/CMakeLists.txt

@@ -0,0 +1,12 @@
+#
+# Copyright (c) 2018 Peter Bigot Consulting, LLC
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+cmake_minimum_required(VERSION 3.8.2)
+include($ENV{ZEPHYR_BASE}/cmake/app/boilerplate.cmake NO_POLICY_SCOPE)
+project(sht3xd)
+
+FILE(GLOB app_sources src/*.c)
+target_sources(app PRIVATE ${app_sources})

samples/sensor/sht3xd/README.rst

@@ -0,0 +1,52 @@
+.. _sht3xd:
+
+SHT3XD: High accuracy digital I2C humidity sensor
+#################################################
+
+Description
+***********
+
+This sample application periodically (2 Hz) measures the ambient
+temperature and humidity. The result is written to the console.
+Optionally, it also shows how to use the upper threshold triggers.
+
+References
+**********
+
+ - `SHT3X-DIS sensor <https://www.sensirion.com/en/environmental-sensors/humidity-sensors/digital-humidity-sensors-for-various-applications/>`_
+
+Wiring
+*******
+
+This sample uses the SHT3X_DIS sensor controlled using the I2C interface.
+Connect Supply: **VDD**, **GND** and Interface: **SDA**, **SCL**
+and optionally connect the **ALERT** to a interrupt capable GPIO.
+The supply voltage can be in the 2.15V to 5.5V range.
+Depending on the baseboard used, the **SDA** and **SCL** lines require Pull-Up
+resistors.
+
+Building and Running
+********************
+
+This project outputs sensor data to the console. It requires a SHT3XD
+sensor. It should work with any platform featuring a I2C peripheral
+interface.  It does not work on QEMU.  In this example below the
+:ref:`nrf51_ble400` board is used.
+
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/sensors/sht3xd
+   :board: nrf51_ble400
+   :goals: build flash
+
+Sample Output
+=============
+
+.. code-block:: console
+
+   SHT3XD: 19.64 Cel ; 41.96 %RH
+   SHT3XD: 19.74 Cel ; 42.06 %RH
+   SHT3XD: 19.75 Cel ; 42.08 %RH
+
+<repeats endlessly>
+

samples/sensor/sht3xd/dts_fixup.h

@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2018 Peter Bigot Consulting, LLC
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#if defined(CONFIG_HAS_DTS_I2C)
+
+#ifndef DT_SHT3XD_NAME
+
+#ifdef DT_NORDIC_NRF_I2C_40003000_SENSIRION_SHT3XD_44_LABEL
+
+#define DT_SHT3XD_NAME			DT_NORDIC_NRF_I2C_40003000_SENSIRION_SHT3XD_44_LABEL
+#define DT_SHT3XD_I2C_ADDR		DT_NORDIC_NRF_I2C_40003000_SENSIRION_SHT3XD_44_BASE_ADDRESS
+#define DT_SHT3XD_I2C_MASTER_DEV_NAME	DT_NORDIC_NRF_I2C_40003000_SENSIRION_SHT3XD_44_BUS_NAME
+
+#ifdef DT_NORDIC_NRF_I2C_40003000_SENSIRION_SHT3XD_44_ALERT_GPIOS_CONTROLLER
+#define DT_SHT3XD_GPIO_ALERT_DEV_NAME	DT_NORDIC_NRF_I2C_40003000_SENSIRION_SHT3XD_44_ALERT_GPIOS_CONTROLLER
+#define DT_SHT3XD_GPIO_ALERT_PIN	DT_NORDIC_NRF_I2C_40003000_SENSIRION_SHT3XD_44_ALERT_GPIOS_PIN
+#endif /* GPIO_ALERT */
+
+#else /* board selection */
+#error No device tree bindings for SHT3XD
+#endif /* board selection */
+
+#endif /* DT_SHT3XD_NAME */
+
+#endif /* CONFIG_HAS_DTS_I2C */

samples/sensor/sht3xd/nrf51_ble400.overlay

@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2018 Peter Bigot Consulting, LLC
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+&i2c0 {
+        status = "ok";
+        sda-pin = <0>;
+        scl-pin = <1>;
+
+	sht3xd: sht3xd@44 {
+		compatible = "sensirion,sht3xd";
+		reg = <0x44>;
+		label = "SHT3XD";
+		alert-gpios = <&gpio0 2 GPIO_INT_ACTIVE_HIGH>;
+	};
+};

samples/sensor/sht3xd/prj.conf

@@ -0,0 +1,10 @@
+#
+# Copyright (c) 2018 Peter Bigot Consulting, LLC
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+CONFIG_STDOUT_CONSOLE=y
+CONFIG_I2C=y
+CONFIG_SENSOR=y
+CONFIG_SHT3XD=y

samples/sensor/sht3xd/prj_nrf.conf

@@ -0,0 +1,13 @@
+#
+# Copyright (c) 2018 Peter Bigot Consulting, LLC
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+CONFIG_STDOUT_CONSOLE=y
+CONFIG_I2C=y
+CONFIG_I2C_NRFX=y
+CONFIG_I2C_0=y
+CONFIG_SENSOR=y
+CONFIG_SHT3XD=y
+CONFIG_SHT3XD_TRIGGER_OWN_THREAD=y

samples/sensor/sht3xd/sample.yaml

@@ -0,0 +1,14 @@
+#
+# Copyright (c) 2018 Peter Bigot Consulting, LLC
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+sample:
+  name: SHT3XD Sensor Sample
+tests:
+  test:
+    build_only: true
+    platform_whitelist: nrf51_ble400
+    tags: sensors
+    extra_args: CONF_FILE="prj_nrf.conf"

samples/sensor/sht3xd/src/main.c

@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 2018 Peter Bigot Consulting, LLC
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr.h>
+#include <device.h>
+#include <sensor.h>
+#include <stdio.h>
+
+#define ALERT_HUMIDITY 40
+
+#ifdef CONFIG_SHT3XD_TRIGGER
+static volatile bool alerted;
+
+static void trigger_handler(struct device *dev, struct sensor_trigger *trig)
+{
+	alerted = !alerted;
+}
+
+#endif
+
+void main(void)
+{
+	struct device *dev = device_get_binding(DT_SHT3XD_NAME);
+	int rc;
+
+	if (dev == NULL) {
+		printf("Could not get SHT3XD device\n");
+		return;
+	}
+
+#ifdef CONFIG_SHT3XD_TRIGGER
+	struct sensor_trigger trig = {
+		.type = SENSOR_TRIG_THRESHOLD,
+		.chan = SENSOR_CHAN_HUMIDITY,
+	};
+	struct sensor_value lo_thr = { 0 };
+	struct sensor_value hi_thr = { ALERT_HUMIDITY };
+	bool last_alerted = false;
+
+	rc = sensor_attr_set(dev, SENSOR_CHAN_HUMIDITY,
+			     SENSOR_ATTR_LOWER_THRESH, &lo_thr);
+	if (rc == 0) {
+		rc = sensor_attr_set(dev, SENSOR_CHAN_HUMIDITY,
+				     SENSOR_ATTR_UPPER_THRESH, &hi_thr);
+	}
+	if (rc == 0) {
+		rc = sensor_trigger_set(dev, &trig, trigger_handler);
+	}
+	printf("Alert outside %d..%d %%RH got %d\n", lo_thr.val1,
+	       hi_thr.val1, rc);
+#endif
+
+	while (true) {
+		struct sensor_value temp, hum;
+
+#ifdef CONFIG_SHT3XD_TRIGGER
+		if (alerted != last_alerted) {
+			static const char *const alert_str[] = {
+				"below",
+				"above",
+			};
+			printf("Humidity %s %d!\n", alert_str[alerted],
+			       hi_thr.val1);
+			last_alerted = alerted;
+		}
+#endif
+		rc = sensor_sample_fetch(dev);
+		if (rc == 0) {
+			rc = sensor_channel_get(dev, SENSOR_CHAN_AMBIENT_TEMP,
+						&temp);
+		}
+		if (rc == 0) {
+			rc = sensor_channel_get(dev, SENSOR_CHAN_HUMIDITY,
+						&hum);
+		}
+		if (rc != 0) {
+			printf("SHT3XD: failed: %d\n", rc);
+			break;
+		}
+		printf("SHT3XD: %.2f Cel ; %0.2f %%RH\n",
+		       sensor_value_to_double(&temp),
+		       sensor_value_to_double(&hum));
+
+		k_sleep(2000);
+	}
+}

tests/drivers/build_all/dts_fixup.h

@@ -138,6 +138,14 @@
 #define DT_LIS2DH_INT2_GPIO_PIN 1
 #endif
 
+#ifndef DT_SHT3XD_NAME
+#define DT_SHT3XD_NAME ""
+#define DT_SHT3XD_I2C_ADDR 0
+#define DT_SHT3XD_I2C_MASTER_DEV_NAME ""
+#define DT_SHT3XD_GPIO_ALERT_DEV_NAME ""
+#define DT_SHT3XD_GPIO_ALERT_PIN 0
+#endif
+
 #endif /* CONFIG_HAS_DTS_I2C */
 
 #if defined(CONFIG_HAS_DTS_SPI)