Fix for issue #2589 - i2Csetup for ESP 32-C3

boards/ESP32.py

@@ -188,9 +188,11 @@ def get_pins():
   pinutils.findpin(pins, "PD32", True)["functions"]["USART1_RX"]=0; # doesn't match jshardwareUart?
   pinutils.findpin(pins, "PD16", True)["functions"]["USART3_RX"]=0;
   pinutils.findpin(pins, "PD17", True)["functions"]["USART3_TX"]=0; 
+  pinutils.findpin(pins, "PD16", True)["functions"]["I2C2_SCL"]=1;  # added for issue #2589 fix
+  pinutils.findpin(pins, "PD17", True)["functions"]["I2C2_SDA"]=1;  # added for issue #2589 fix
 
-  pinutils.findpin(pins, "PD21", True)["functions"]["I2C1_SCL"]=0;
-  pinutils.findpin(pins, "PD22", True)["functions"]["I2C1_SDA"]=0;
+  pinutils.findpin(pins, "PD22", True)["functions"]["I2C1_SCL"]=0; # SCL moved from P21 for issue #2589
+  pinutils.findpin(pins, "PD21", True)["functions"]["I2C1_SDA"]=0; # SDA moved from P22 for issue #2589
   pinutils.findpin(pins, "PD14", True)["functions"]["SPI1_SCLK"]=0;
   pinutils.findpin(pins, "PD12", True)["functions"]["SPI1_MISO"]=0;
   pinutils.findpin(pins, "PD13", True)["functions"]["SPI1_MOSI"]=0;

targets/esp32/jshardwareI2c.c

@@ -84,46 +84,50 @@ int getI2cFromDevice( IOEventFlags device  ) {
   }
 }
 
-/** Set-up I2C master for ESP32, default pins are SCL:21, SDA:22. Only device I2C1 is supported
- *  and only master mode. */
+/** Set-up I2C master for ESP32, default pins are target dependent, defined in board.py file 
+ *  Master mode only - handles I2C1 and I2C2 (if available eg on ESP32) */
 void jshI2CSetup(IOEventFlags device, JshI2CInfo *info) {
   int i2c_master_port = getI2cFromDevice(device);
   if (i2c_master_port == -1) {
-    jsExceptionHere(JSET_ERROR,"Only I2C1 and I2C2 supported");
+    jsExceptionHere(JSET_ERROR,"Only I2C1 and I2C2 (if available on target) supported");
     return;
   }
   if(jshIsDeviceInitialised(device)){
-  i2c_driver_delete(i2c_master_port);
-  }
-  Pin scl;
-  Pin sda;
-  if ( i2c_master_port == I2C_NUM_0 ) {
-    scl = info->pinSCL != PIN_UNDEFINED ? info->pinSCL : 21;
-    sda = info->pinSDA != PIN_UNDEFINED ? info->pinSDA : 22;
-  }
-#if ESPR_I2C_COUNT>1
-  // Unsure on what to default these pins to?
-  if ( i2c_master_port == I2C_NUM_1 ) {
-    scl = info->pinSCL != PIN_UNDEFINED ? info->pinSCL : 16;
-    sda = info->pinSDA != PIN_UNDEFINED ? info->pinSDA : 17;
+    i2c_driver_delete(i2c_master_port);
   }
-#endif
+  JshPinFunction funcType = jshGetPinFunctionFromDevice(device);
+  if (!jshIsPinValid(info->pinSCL)) info->pinSCL = jshFindPinForFunction(funcType, JSH_I2C_SCL);
+  if (!jshIsPinValid(info->pinSDA)) info->pinSDA = jshFindPinForFunction(funcType, JSH_I2C_SDA);
+
+  #ifdef DEBUG
+    char funcTypeStr[50];
+    jshPinFunctionToString(funcType, JSPFTS_DEVICE | JSPFTS_DEVICE_NUMBER, funcTypeStr, sizeof(funcTypeStr));
+    jsDebug(DBG_INFO, "jshI2CSetup: I2C pins on device: %s, identified as sda: %d, scl: %d\n",
+          funcTypeStr, info->pinSDA, info->pinSCL);
+  #endif
 
   i2c_config_t conf;
   conf.mode = I2C_MODE_MASTER;
-  conf.sda_io_num = pinToESP32Pin(sda);
+  conf.sda_io_num = pinToESP32Pin(info->pinSDA);
   conf.sda_pullup_en = GPIO_PULLUP_ENABLE;
-  conf.scl_io_num = pinToESP32Pin(scl);
+  conf.scl_io_num = pinToESP32Pin(info->pinSCL);
   conf.scl_pullup_en = GPIO_PULLUP_ENABLE;
   conf.master.clk_speed = info->bitrate;
+
+  #if defined(CONFIG_IDF_TARGET_ESP32C3) || defined(CONFIG_IDF_TARGET_ESP32S3)     // added to resolve issue #2589 for IDF v4.x
+    conf.clk_flags = 0;     // will always select 2MZ XTAL clock - Although speed set as in conf.master.clk_speed
+    // conf.clk_flags = 1;  // or set driver to ignore XTAL clock and use 1MHz RTC clock (better for low power?)
+    // ref https://docs.espressif.com/projects/esp-idf/en/v4.4/esp32s3/api-reference/peripherals/i2c.html#source-clock-configuration
+  #endif
+
   esp_err_t err=i2c_param_config(i2c_master_port, &conf);
   if ( err == ESP_ERR_INVALID_ARG ) {
     jsExceptionHere(JSET_ERROR,"jshI2CSetup: Invalid arguments");
-  return;
+    return;
   }
   err=i2c_driver_install(i2c_master_port, conf.mode, 0, 0, 0);
   if ( err == ESP_OK ) {
-    jsDebug(DBG_INFO, "jshI2CSetup: driver installed, sda: %d scl: %d freq: %d, \n", sda, scl, info->bitrate);
+    jsDebug(DBG_INFO, "jshI2CSetup: driver installed with, sda: %d scl: %d freq: %d, \n", info->pinSDA, info->pinSCL, conf.master.clk_speed);
     jshSetDeviceInitialised(device, true);
   } else {
     checkError("jshI2CSetup",err);