driver(adc): fix unit test for ADC-DMA (test_esp32s2.c); fix unit test for ADC-DMA (test_esp32s2.c); fix commit in adc dirver.

components/driver/test/include/test/test_common_adc.h

@@ -0,0 +1,34 @@
+// Copyright 2015-2020 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+
+#include "driver/adc.h"
+
+/**@{*/
+/**
+ * Tie the ADC channel input to the middle (1.4V) by connecting both internal pullup and pulldown.
+ *
+ * `tie_middle`: 1.4v;
+ * `tie_high`  : 3.3v;
+ * `tie_low`   : 0v;
+ *
+ * @param adc_unit_t ADC unit.
+ * @param adc_channel_t ADC channel.
+ */
+void adc_fake_tie_middle(adc_unit_t adc_unit, adc_channel_t channel);
+void adc_fake_tie_high(adc_unit_t adc_unit, adc_channel_t channel);
+void adc_fake_tie_low(adc_unit_t adc_unit, adc_channel_t channel);
+void adc_io_normal(adc_unit_t adc_unit, adc_channel_t channel);
+/**@}*/