Simplify analogRead function

Author: mikee47

Sming/Arch/Esp32/Core/adc.cpp

@@ -1,90 +1,17 @@
 #include <driver/adc.h>
-#include <soc/adc_periph.h>
-#if ESP_IDF_VERSION_MAJOR < 5
-#include <esp_adc_cal.h>
-#endif
 #include <debug_progmem.h>
-#include <Digital.h>
-
-#define DEFAULT_VREF 1100 // Use adc2_vref_to_gpio() to obtain a better estimate
-
-namespace
-{
-struct AdcInfo {
-	adc_unit_t adc;
-	adc_channel_t channel;
-};
-
-bool lookupAdc(uint16_t pin, AdcInfo& info)
-{
-	for(unsigned adc = 0; adc < SOC_ADC_PERIPH_NUM; ++adc) {
-		for(unsigned ch = 0; ch < SOC_ADC_MAX_CHANNEL_NUM; ++ch) {
-			if(adc_channel_io_map[adc][ch] == pin) {
-				info.adc = adc_unit_t(adc);
-				info.channel = adc_channel_t(ch);
-				return true;
-			}
-		}
-	}
-
-	return false;
-}
-
-} // namespace
 
 uint16_t analogRead(uint16_t pin)
 {
-	AdcInfo info;
-	if(!lookupAdc(pin, info)) {
+	adc_oneshot_unit_init_cfg_t init_config{};
+	adc_channel_t channel;
+	esp_err_t err = adc_oneshot_io_to_channel(pin, &init_config.unit_id, &channel);
+	if(err != ESP_OK) {
 		debug_e("Pin %u is not ADC pin!", pin);
 		return 0;
 	}
 
-	pinMode(pin, ANALOG);
-
-#if ESP_IDF_VERSION_MAJOR < 5
-
-	constexpr adc_atten_t attenuation{ADC_ATTEN_DB_0};
-	esp_adc_cal_characteristics_t adcChars{};
-
-	auto adcWidth = adc_bits_width_t(ADC_WIDTH_MAX - 1);
-
-	// Configure
-	if(info.adc == ADC_UNIT_2) {
-		adc2_config_channel_atten(adc2_channel_t(info.channel), attenuation);
-	} else {
-		adc1_config_width(adcWidth);
-		adc1_config_channel_atten(adc1_channel_t(info.channel), attenuation);
-	}
-
-	// Characterize
-	esp_adc_cal_characterize(info.adc, attenuation, adcWidth, DEFAULT_VREF, &adcChars);
-
-	// Sample
-	if(info.adc == ADC_UNIT_2) {
-		int value{0};
-		esp_err_t r = adc2_get_raw(adc2_channel_t(info.channel), adcWidth, &value);
-		if(r == ESP_OK) {
-			return value;
-		} else if(r == ESP_ERR_INVALID_STATE) {
-			debug_e("GPIO%u: %s: ADC2 not initialized yet.", pin, esp_err_to_name(r));
-		} else if(r == ESP_ERR_TIMEOUT) {
-			debug_e("GPIO%u: %s: ADC2 is in use by Wi-Fi.", pin, esp_err_to_name(r));
-		} else {
-			debug_e("GPIO%u: %s", pin, esp_err_to_name(r));
-		}
-
-		return value;
-	}
-
-	return adc1_get_raw(adc1_channel_t(info.channel));
-
-#else
-
 	// Initialise unit
-	adc_oneshot_unit_init_cfg_t init_config{
-		.unit_id = info.adc,
-	};
 	adc_oneshot_unit_handle_t adc_handle;
 	ESP_ERROR_CHECK(adc_oneshot_new_unit(&init_config, &adc_handle));
 
@@ -93,21 +20,12 @@ uint16_t analogRead(uint16_t pin)
 		.atten = ADC_ATTEN_DB_0,
 		.bitwidth = ADC_BITWIDTH_DEFAULT,
 	};
-	ESP_ERROR_CHECK(adc_oneshot_config_channel(adc_handle, info.channel, &channel_config));
-
-	// Calibration
-	// adc_cali_handle_t adc1_cali_handle = NULL;
-	// bool do_calibration1 = example_adc_calibration_init(ADC_UNIT_1, ADC_ATTEN_DB_11, &adc1_cali_handle);
+	ESP_ERROR_CHECK(adc_oneshot_config_channel(adc_handle, channel, &channel_config));
 
 	int rawSampleValue{0};
-	ESP_ERROR_CHECK(adc_oneshot_read(adc_handle, info.channel, &rawSampleValue));
-
-	// ESP_ERROR_CHECK(adc_cali_raw_to_voltage(adc1_cali_handle, adc_raw[0][0], &voltage[0][0]));
-	// ESP_LOGI(TAG, "ADC%d Channel[%d] Cali Voltage: %d mV", ADC_UNIT_1 + 1, EXAMPLE_ADC1_CHAN0, voltage[0][0]);
+	ESP_ERROR_CHECK(adc_oneshot_read(adc_handle, channel, &rawSampleValue));
 
 	ESP_ERROR_CHECK(adc_oneshot_del_unit(adc_handle));
 
 	return rawSampleValue;
-
-#endif
 }