zephyr: tests: Test `common/adc.c` host command

Test the host command for querying an ADC channel

BRANCH=None
BUG=None
TEST=./twister

Signed-off-by: Tristan Honscheid <honscheid@google.com>
Change-Id: Ifd708fc770881c8c16726d969daf364d7eee4a55
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3925109
Code-Coverage: Zoss <zoss-cl-coverage@prod.google.com>
Commit-Queue: Aaron Massey <aaronmassey@google.com>
Reviewed-by: Aaron Massey <aaronmassey@google.com>

3 files changed, 63 insertions, 1 deletions

diff --git a/zephyr/shim/src/adc.c b/zephyr/shim/src/adc.c
index e14ef9f20f..9d5e64376c 100644
--- a/zephyr/shim/src/adc.c
+++ b/zephyr/shim/src/adc.c
@@ -61,7 +61,7 @@ static int init_device_bindings(const struct device *device)
 }
 SYS_INIT(init_device_bindings, POST_KERNEL, 51);
 
-int adc_read_channel(enum adc_channel ch)
+test_mockable int adc_read_channel(enum adc_channel ch)
 {
 	int ret = 0, rv;
 	struct adc_sequence seq = {
diff --git a/zephyr/test/drivers/host_cmd/CMakeLists.txt b/zephyr/test/drivers/host_cmd/CMakeLists.txt
index cde1dbd524..286685089b 100644
--- a/zephyr/test/drivers/host_cmd/CMakeLists.txt
+++ b/zephyr/test/drivers/host_cmd/CMakeLists.txt
@@ -3,6 +3,7 @@
 # found in the LICENSE file.
 
 target_sources(app PRIVATE
+    src/adc.c
     src/battery_cut_off.c
     src/get_panic_info.c
     src/get_pd_port_caps.c
diff --git a/zephyr/test/drivers/host_cmd/src/adc.c b/zephyr/test/drivers/host_cmd/src/adc.c
new file mode 100644
index 0000000000..6b2bef1165
--- /dev/null
+++ b/zephyr/test/drivers/host_cmd/src/adc.c
@@ -0,0 +1,61 @@
+/* Copyright 2022 The ChromiumOS Authors
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include <zephyr/drivers/emul.h>
+#include <zephyr/fff.h>
+#include <zephyr/ztest.h>
+
+#include "adc.h"
+#include "host_command.h"
+#include "test/drivers/test_state.h"
+#include "test/drivers/utils.h"
+
+FAKE_VALUE_FUNC(int, adc_read_channel, enum adc_channel);
+
+ZTEST(hc_adc, normal_path)
+{
+	struct ec_params_adc_read params = {
+		.adc_channel = ADC_TEMP_SENSOR_CHARGER,
+	};
+	struct ec_response_adc_read response;
+	uint16_t ret;
+
+	adc_read_channel_fake.return_val = 123;
+
+	struct host_cmd_handler_args args = BUILD_HOST_COMMAND(
+		EC_CMD_ADC_READ, UINT8_C(0), response, params);
+
+	ret = host_command_process(&args);
+
+	zassert_ok(ret, "Host command returned %u", ret);
+	zassert_equal(1, adc_read_channel_fake.call_count);
+	zassert_equal(123, response.adc_value);
+}
+
+ZTEST(hc_adc, bad_ch_number)
+{
+	struct ec_params_adc_read params = {
+		.adc_channel = ADC_CH_COUNT + 1, /* Invalid */
+	};
+	struct ec_response_adc_read response;
+	uint16_t ret;
+
+	struct host_cmd_handler_args args = BUILD_HOST_COMMAND(
+		EC_CMD_ADC_READ, UINT8_C(0), response, params);
+
+	ret = host_command_process(&args);
+
+	zassert_equal(EC_RES_INVALID_PARAM, ret, "Host command returned %u",
+		      ret);
+}
+
+static void reset(void *data)
+{
+	ARG_UNUSED(data);
+
+	RESET_FAKE(adc_read_channel);
+}
+
+ZTEST_SUITE(hc_adc, drivers_predicate_post_main, NULL, reset, reset, NULL);