samples: esp32: temp: CPU die temperature sample

Add die temperature measure sample for ESP32 targets
esp32s2_saola, esp32c3_devkitm.

Signed-off-by: Marek Matej <marek.matej@espressif.com>

samples/sensor/esp32_temp_sensor/CMakeLists.txt

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+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(esp32_temp_sensor)
+
+FILE(GLOB app_sources src/*.c)
+target_sources(app PRIVATE ${app_sources})

samples/sensor/esp32_temp_sensor/README.rst

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+.. _esp32_temp_sensor:
+
+ESP32 Temperature Sensor
+########################
+
+Overview
+********
+
+This sample periodically reads temperature from the ESP32-S2 and ESP32-C3
+Internal Temperature Sensor and display the results.
+
+Building and Running
+********************
+
+In order to run this sample, make sure to enable ``esp32_temp`` node in your
+board DT file.
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/sensor/esp32_temp_sensor
+   :board: esp32s2_saola
+   :goals: build
+   :compact:
+
+Sample Output
+=============
+
+.. code-block:: console
+
+    Current temperature: 22.6 °C
+    Current temperature: 22.8 °C
+    Current temperature: 23.1 °C

samples/sensor/esp32_temp_sensor/boards/esp32c3_devkitm.conf

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+CONFIG_NEWLIB_LIBC=y

samples/sensor/esp32_temp_sensor/boards/esp32c3_devkitm.overlay

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+/*
+ * Copyright (c) 2022 Espressif Systems (Shanghai) Co., Ltd.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Application overlay for creating temperature sensor device instance
+ */
+
+&coretemp {
+    status = "okay";
+};

samples/sensor/esp32_temp_sensor/boards/esp32s2_saola.conf

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+CONFIG_NEWLIB_LIBC=y

samples/sensor/esp32_temp_sensor/boards/esp32s2_saola.overlay

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+/*
+ * Copyright (c) 2022 Espressif Systems (Shanghai) Co., Ltd.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Application overlay for creating temperature sensor device instance
+ */
+
+&coretemp {
+    status = "okay";
+};

samples/sensor/esp32_temp_sensor/prj.conf

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+CONFIG_SENSOR=y
+CONFIG_PRINTK=y
+CONFIG_CBPRINTF_FP_SUPPORT=y

samples/sensor/esp32_temp_sensor/sample.yaml

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+sample:
+  description: Usage of ESP32 temperature sensor
+  name: esp32_temp_sensor
+tests:
+  sample.sensor.esp32_temp_sensor:
+    tags: sensors
+    tags: tests
+    filter: dt_compat_enabled("espressif,esp32-temp")
+    harness: console
+    harness_config:
+      type: one_line
+      regex:
+        - "Current temperature: [1-5][0-9].[0-9] °C"

samples/sensor/esp32_temp_sensor/src/main.c

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+/*
+ * Copyright (c) 2022 Espressif Systems (Shanghai) Co., Ltd.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/kernel.h>
+#include <zephyr/device.h>
+#include <zephyr/drivers/sensor.h>
+#include <zephyr/sys/printk.h>
+
+#if CONFIG_SOC_ESP32
+#error "Temperature sensor is not supported on ESP32 soc"
+#endif /* CONFIG_SOC_ESP32 */
+
+void main(void)
+{
+	const struct device *const dev = DEVICE_DT_GET_ONE(espressif_esp32_temp);
+	struct sensor_value val;
+	int rc;
+
+	if (!device_is_ready(dev)) {
+		printk("Temperature sensor is not ready\n");
+		return;
+	}
+
+	printk("ESP32 Die temperature sensor test\n");
+
+	while (1) {
+		k_sleep(K_MSEC(300));
+
+		/* fetch sensor samples */
+		rc = sensor_sample_fetch(dev);
+		if (rc) {
+			printk("Failed to fetch sample (%d)\n", rc);
+			return;
+		}
+
+		rc = sensor_channel_get(dev, SENSOR_CHAN_DIE_TEMP, &val);
+		if (rc) {
+			printk("Failed to get data (%d)\n", rc);
+			return;
+		}
+
+		printk("Current temperature: %.1f °C\n", sensor_value_to_double(&val));
+	}
+}