zephyr: drivers: add temp_sensor test suite

Temperature sensors are accessed through temp_sensor_read() for which
this test suite is created. Tested functionalities are:
- Error code from underlying driver is returned.
- Unknown temperature sensor id is rejected.
- Temperature from underlying driver is returned. Value is not
  extensively tested, because it is done in thermistor test suite.

BUG=b:184857072
BRANCH=none
TEST=run zmake drivers test

Signed-off-by: Tomasz Michalec <tm@semihalf.com>
Change-Id: I6c2df39a70e8ac57325aa9e1f49e7a9bd2340fae
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2886889
Reviewed-by: Simon Glass <sjg@chromium.org>

2 files changed, 134 insertions, 0 deletions

diff --git a/zephyr/test/drivers/src/main.c b/zephyr/test/drivers/src/main.c
index b047038153..f1a080435f 100644
--- a/zephyr/test/drivers/src/main.c
+++ b/zephyr/test/drivers/src/main.c
@@ -11,6 +11,7 @@ extern void test_suite_battery(void);
 extern void test_suite_cbi(void);
 extern void test_suite_smart_battery(void);
 extern void test_suite_thermistor(void);
+extern void test_suite_temp_sensor(void);
 
 void test_main(void)
 {
@@ -23,4 +24,5 @@ void test_main(void)
 	test_suite_cbi();
 	test_suite_smart_battery();
 	test_suite_thermistor();
+	test_suite_temp_sensor();
 }
diff --git a/zephyr/test/drivers/src/temp_sensor.c b/zephyr/test/drivers/src/temp_sensor.c
new file mode 100644
index 0000000000..2e25bab67a
--- /dev/null
+++ b/zephyr/test/drivers/src/temp_sensor.c
@@ -0,0 +1,132 @@
+/* Copyright 2021 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include <zephyr.h>
+#include <ztest.h>
+#include <drivers/adc.h>
+#include <drivers/adc/adc_emul.h>
+#include <drivers/gpio.h>
+#include <drivers/gpio/gpio_emul.h>
+
+#include <math.h>
+
+#include "common.h"
+#include "temp_sensor.h"
+#include "temp_sensor/temp_sensor.h"
+
+#define GPIO_PG_EC_DSW_PWROK_PATH DT_PATH(named_gpios, pg_ec_dsw_pwrok)
+#define GPIO_PG_EC_DSW_PWROK_PORT DT_GPIO_PIN(GPIO_PG_EC_DSW_PWROK_PATH, gpios)
+
+#define ADC_DEVICE_NAME		DT_LABEL(DT_NODELABEL(adc0))
+#define ADC_CHANNELS_NUM	DT_PROP(DT_NODELABEL(adc0), nchannels)
+
+/** Test error code when invalid sensor is passed to temp_sensor_read() */
+static void test_temp_sensor_wrong_id(void)
+{
+	int temp;
+
+	zassert_equal(EC_ERROR_INVAL, temp_sensor_read(TEMP_SENSOR_COUNT,
+						       &temp),
+		      NULL);
+}
+
+/** Test error code when temp_sensor_read() is called with powered off ADC */
+static void test_temp_sensor_adc_error(void)
+{
+	const struct device *gpio_dev =
+		DEVICE_DT_GET(DT_GPIO_CTLR(GPIO_PG_EC_DSW_PWROK_PATH, gpios));
+	int temp;
+
+	zassert_not_null(gpio_dev, "Cannot get GPIO device");
+
+	/*
+	 * pg_ec_dsw_pwrok = 0 means ADC is not powered.
+	 * adc_read will return error
+	 */
+	zassert_ok(gpio_emul_input_set(gpio_dev, GPIO_PG_EC_DSW_PWROK_PORT, 0),
+		   NULL);
+
+	zassert_equal(EC_ERROR_NOT_POWERED,
+		      temp_sensor_read(TEMP_SENSOR_CHARGER, &temp), NULL);
+	zassert_equal(EC_ERROR_NOT_POWERED,
+		      temp_sensor_read(TEMP_SENSOR_DDR_SOC, &temp), NULL);
+	zassert_equal(EC_ERROR_NOT_POWERED,
+		      temp_sensor_read(TEMP_SENSOR_FAN, &temp), NULL);
+	zassert_equal(EC_ERROR_NOT_POWERED,
+		      temp_sensor_read(TEMP_SENSOR_PP3300_REGULATOR, &temp),
+		      NULL);
+
+	/* power ADC */
+	zassert_ok(gpio_emul_input_set(gpio_dev, GPIO_PG_EC_DSW_PWROK_PORT, 1),
+		   NULL);
+}
+
+/** Simple ADC emulator custom function which always return error */
+static int adc_error_func(const struct device *dev, unsigned int channel,
+			  void *param, uint32_t *result)
+{
+	return -EINVAL;
+}
+
+/**
+ * Set valid response only for ADC channel connected with tested sensor.
+ * Check if temp_sensor_read() from tested sensor returns EC_SUCCESS and
+ * valid temperature. Set invalid response on ADC channel for next test.
+ */
+static void check_valid_temperature(const struct device *adc_dev, int sensor)
+{
+	int temp;
+
+	/* ADC channel of tested sensor return valid value */
+	zassert_ok(adc_emul_const_value_set(adc_dev, temp_sensors[sensor].idx,
+					    1000),
+		   "adc_emul_const_value_set() failed (sensor %d)", sensor);
+	zassert_equal(EC_SUCCESS, temp_sensor_read(sensor, &temp), NULL);
+	zassert_within(temp, 273 + 50, 51,
+		       "Expected temperature in 0*C-100*C, got %d*C (sensor %d)",
+		       temp - 273, sensor);
+	/* Return error on ADC channel of tested sensor */
+	zassert_ok(adc_emul_value_func_set(adc_dev, temp_sensors[sensor].idx,
+					   adc_error_func, NULL),
+		   "adc_emul_value_func_set() failed (sensor %d)", sensor);
+}
+
+/** Test if temp_sensor_read() returns temperature on success */
+static void test_temp_sensor_read(void)
+{
+	const struct device *adc_dev = device_get_binding(ADC_DEVICE_NAME);
+	int chan;
+
+	zassert_not_null(adc_dev, "Cannot get ADC device");
+
+	/* Return error on all ADC channels */
+	for (chan = 0; chan < ADC_CHANNELS_NUM; chan++) {
+		zassert_ok(adc_emul_value_func_set(adc_dev, chan,
+						    adc_error_func, NULL),
+			   "channel %d adc_emul_value_func_set() failed", chan);
+	}
+
+	check_valid_temperature(adc_dev, TEMP_SENSOR_CHARGER);
+	check_valid_temperature(adc_dev, TEMP_SENSOR_DDR_SOC);
+	check_valid_temperature(adc_dev, TEMP_SENSOR_FAN);
+	check_valid_temperature(adc_dev, TEMP_SENSOR_PP3300_REGULATOR);
+}
+
+void test_suite_temp_sensor(void)
+{
+	const struct device *dev =
+		DEVICE_DT_GET(DT_GPIO_CTLR(GPIO_PG_EC_DSW_PWROK_PATH, gpios));
+
+	zassert_not_null(dev, NULL);
+	/* Before tests make sure that power pin is set. */
+	zassert_ok(gpio_emul_input_set(dev, GPIO_PG_EC_DSW_PWROK_PORT, 1),
+		   NULL);
+
+	ztest_test_suite(temp_sensor,
+			 ztest_user_unit_test(test_temp_sensor_wrong_id),
+			 ztest_user_unit_test(test_temp_sensor_adc_error),
+			 ztest_user_unit_test(test_temp_sensor_read));
+	ztest_run_test_suite(temp_sensor);
+}