adc fixes and improvements (espressif#6799)

Fixed channel / unit selection for ESP32C3 (has only 5 channels on 1 adc unit).

Removed unnecessary includes.

Fixed different attenuation on channels to be taken in care in __analogReadMilliVolt.

All chips in __analogReadMilliVolts now use adc characteristics + calculation from raw to voltage as ESP32 does.

Author: P-R-O-C-H-Y

cores/esp32/esp32-hal-adc.c

@@ -13,50 +13,28 @@
 // limitations under the License.
 
 #include "esp32-hal-adc.h"
-#include "freertos/FreeRTOS.h"
-#include "freertos/task.h"
-#include "esp_attr.h"
-#include "soc/rtc_cntl_reg.h"
 #include "driver/adc.h"
-
-#include "esp_system.h"
-#ifdef ESP_IDF_VERSION_MAJOR // IDF 4+
-#if CONFIG_IDF_TARGET_ESP32 // ESP32/PICO-D4
 #include "esp_adc_cal.h"
-#include "soc/sens_reg.h"
-#include "soc/rtc_io_reg.h"
-#include "esp32/rom/ets_sys.h"
-#include "esp_intr_alloc.h"
-#include "soc/dac_channel.h"
-#define DEFAULT_VREF    1100
-static esp_adc_cal_characteristics_t *__analogCharacteristics[2] = {NULL, NULL};
-static uint16_t __analogVRef = 0;
-static uint8_t __analogVRefPin = 0;
-#elif CONFIG_IDF_TARGET_ESP32S2
-#include "esp32s2/rom/ets_sys.h"
-#include "soc/sens_reg.h"
-#include "soc/rtc_io_reg.h"
+
+#if SOC_DAC_SUPPORTED           //ESP32, ESP32S2
 #include "soc/dac_channel.h"
-#elif CONFIG_IDF_TARGET_ESP32S3
-#include "esp32s3/rom/ets_sys.h"
 #include "soc/sens_reg.h"
 #include "soc/rtc_io_reg.h"
-#elif CONFIG_IDF_TARGET_ESP32C3
-#include "esp32c3/rom/ets_sys.h"
-#else
-#error Target CONFIG_IDF_TARGET is not supported
-#endif
-#else // ESP32 Before IDF 4.0
-#include "rom/ets_sys.h"
-#include "esp_intr.h"
 #endif
 
+#define DEFAULT_VREF    1100
+
 static uint8_t __analogAttenuation = 3;//11db
 static uint8_t __analogWidth = ADC_WIDTH_MAX - 1; //3 for ESP32/ESP32C3; 4 for ESP32S2
 static uint8_t __analogReturnedWidth = SOC_ADC_MAX_BITWIDTH; //12 for ESP32/ESP32C3; 13 for ESP32S2
 static uint8_t __analogClockDiv = 1;
 static adc_attenuation_t __pin_attenuation[SOC_GPIO_PIN_COUNT];
 
+static uint16_t __analogVRef = 0;
+#if CONFIG_IDF_TARGET_ESP32
+static uint8_t __analogVRefPin = 0;
+#endif
+
 static inline uint16_t mapResolution(uint16_t value)
 {
     uint8_t from = __analogWidth + 9;
@@ -117,8 +95,8 @@ void __analogSetPinAttenuation(uint8_t pin, adc_attenuation_t attenuation)
     if(channel < 0 || attenuation > 3){
         return ;
     }
-    if(channel > 9){
-        adc2_config_channel_atten(channel - 10, attenuation);
+    if(channel > (SOC_ADC_MAX_CHANNEL_NUM - 1)){
+        adc2_config_channel_atten(channel - SOC_ADC_MAX_CHANNEL_NUM, attenuation);
     } else {
         adc1_config_channel_atten(channel, attenuation);
     }
@@ -181,8 +159,8 @@ uint16_t __analogRead(uint8_t pin)
         return value;
     }
     __adcAttachPin(pin);
-    if(channel > 9){
-        channel -= 10;
+    if(channel > (SOC_ADC_MAX_CHANNEL_NUM - 1)){
+        channel -= SOC_ADC_MAX_CHANNEL_NUM;
         r = adc2_get_raw( channel, __analogWidth, &value);
         if ( r == ESP_OK ) {
             return mapResolution(value);
@@ -206,7 +184,7 @@ uint32_t __analogReadMilliVolts(uint8_t pin){
         log_e("Pin %u is not ADC pin!", pin);
         return 0;
     }
-#if CONFIG_IDF_TARGET_ESP32
+
     if(!__analogVRef){
         if (esp_adc_cal_check_efuse(ESP_ADC_CAL_VAL_EFUSE_TP) == ESP_OK) {
             log_d("eFuse Two Point: Supported");
@@ -218,6 +196,8 @@ uint32_t __analogReadMilliVolts(uint8_t pin){
         }
         if(!__analogVRef){
             __analogVRef = DEFAULT_VREF;
+
+            #if CONFIG_IDF_TARGET_ESP32
             if(__analogVRefPin){
                 esp_adc_cal_characteristics_t chars;
                 if(adc_vref_to_gpio(ADC_UNIT_2, __analogVRefPin) == ESP_OK){
@@ -227,42 +207,44 @@ uint32_t __analogReadMilliVolts(uint8_t pin){
                     log_d("Vref to GPIO%u: %u", __analogVRefPin, __analogVRef);
                 }
             }
+            #endif
         }
     }
     uint8_t unit = 1;
-    if(channel > 9){
+    if(channel > (SOC_ADC_MAX_CHANNEL_NUM - 1)){
         unit = 2;
     }
+
     uint16_t adc_reading = __analogRead(pin);
-    if(__analogCharacteristics[unit - 1] == NULL){
-        __analogCharacteristics[unit - 1] = calloc(1, sizeof(esp_adc_cal_characteristics_t));
-        if(__analogCharacteristics[unit - 1] == NULL){
-            return 0;
-        }
-        esp_adc_cal_value_t val_type = esp_adc_cal_characterize(unit, __analogAttenuation, __analogWidth, __analogVRef, __analogCharacteristics[unit - 1]);
+
+    uint8_t atten = __analogAttenuation;
+    if (__pin_attenuation[pin] != ADC_ATTENDB_MAX){
+        atten = __pin_attenuation[pin];
+    }
+
+    esp_adc_cal_characteristics_t chars = {};
+    esp_adc_cal_value_t val_type = esp_adc_cal_characterize(unit, atten, __analogWidth, __analogVRef, &chars);
+
+    static bool print_chars_info = true;
+    if(print_chars_info)
+    {
         if (val_type == ESP_ADC_CAL_VAL_EFUSE_TP) {
-            log_i("ADC%u: Characterized using Two Point Value: %u\n", unit, __analogCharacteristics[unit - 1]->vref);
-        } else if (val_type == ESP_ADC_CAL_VAL_EFUSE_VREF) {
-            log_i("ADC%u: Characterized using eFuse Vref: %u\n", unit, __analogCharacteristics[unit - 1]->vref);
-        } else if(__analogVRef != DEFAULT_VREF){
-            log_i("ADC%u: Characterized using Vref to GPIO%u: %u\n", unit, __analogVRefPin, __analogCharacteristics[unit - 1]->vref);
-        } else {
-            log_i("ADC%u: Characterized using Default Vref: %u\n", unit, __analogCharacteristics[unit - 1]->vref);
+            log_i("ADC%u: Characterized using Two Point Value: %u\n", unit, chars.vref);
+        } 
+        else if (val_type == ESP_ADC_CAL_VAL_EFUSE_VREF) {
+            log_i("ADC%u: Characterized using eFuse Vref: %u\n", unit, chars.vref);
+        } 
+        #if CONFIG_IDF_TARGET_ESP32
+        else if(__analogVRef != DEFAULT_VREF){
+            log_i("ADC%u: Characterized using Vref to GPIO%u: %u\n", unit, __analogVRefPin, chars.vref);
         }
+        #endif
+        else {
+            log_i("ADC%u: Characterized using Default Vref: %u\n", unit, chars.vref);
+        }
+        print_chars_info = false;
     }
-    return esp_adc_cal_raw_to_voltage(adc_reading, __analogCharacteristics[unit - 1]);
-#else
-    uint16_t adc_reading = __analogRead(pin);
-    uint16_t max_reading = 8191;
-    uint16_t max_mv = 1100;
-    switch(__analogAttenuation){
-        case 3: max_mv = 3900; break;
-        case 2: max_mv = 2200; break;
-        case 1: max_mv = 1500; break;
-        default: break;
-    }
-    return (adc_reading * max_mv) / max_reading;
-#endif
+    return esp_adc_cal_raw_to_voltage((uint32_t)adc_reading, &chars);
 }
 
 #if CONFIG_IDF_TARGET_ESP32
@@ -297,4 +279,3 @@ extern void analogSetVRefPin(uint8_t pin) __attribute__ ((weak, alias("__analogS
 extern void analogSetWidth(uint8_t bits) __attribute__ ((weak, alias("__analogSetWidth")));
 extern int hallRead() __attribute__ ((weak, alias("__hallRead")));
 #endif
-