support ESP32-S2 CPUs

Note: these don't have Bluetooth and only a single physical core.

arch/esp32/esp32s2.ini

@@ -0,0 +1,47 @@
+[esp32s2_base]
+extends = arduino_base
+platform = platformio/espressif32@^5.2.0
+build_src_filter = 
+  ${arduino_base.build_src_filter} -<platform/nrf52/> -<platform/stm32wl> -<platform/rp2040> -<mesh/eth/> -<nimble/>
+upload_speed = 961200
+monitor_speed = 115200
+debug_init_break = tbreak setup
+monitor_filters = esp32_exception_decoder
+board_build.filesystem = littlefs
+
+# Remove -DMYNEWT_VAL_BLE_HS_LOG_LVL=LOG_LEVEL_CRITICAL for low level BLE logging.
+# See library directory for BLE logging possible values: .pio/libdeps/tbeam/NimBLE-Arduino/src/log_common/log_common.h
+# This overrides the BLE logging default of LOG_LEVEL_INFO (1) from: .pio/libdeps/tbeam/NimBLE-Arduino/src/esp_nimble_cfg.h
+build_flags =
+  ${arduino_base.build_flags} 
+  -Wall 
+  -Wextra 
+  -Isrc/platform/esp32 
+  -std=c++11 
+  -DLOG_LOCAL_LEVEL=ESP_LOG_DEBUG 
+  -DCORE_DEBUG_LEVEL=ARDUHAL_LOG_LEVEL_DEBUG 
+  -DMYNEWT_VAL_BLE_HS_LOG_LVL=LOG_LEVEL_CRITICAL
+  -DAXP_DEBUG_PORT=Serial 
+  -DCONFIG_BT_NIMBLE_ENABLED 
+  -DCONFIG_NIMBLE_CPP_LOG_LEVEL=2
+  -DCONFIG_BT_NIMBLE_MAX_CCCDS=20
+  -DESP_OPENSSL_SUPPRESS_LEGACY_WARNING
+  -DHAS_BLUETOOTH=0
+  -DDEBUG_HEAP 
+  
+lib_deps =
+  ${arduino_base.lib_deps}
+  ${networking_base.lib_deps}
+  ${environmental_base.lib_deps}
+  https://github.com/meshtastic/esp32_https_server.git#23665b3adc080a311dcbb586ed5941b5f94d6ea2
+  https://github.com/lewisxhe/XPowersLib.git#84b7373faea3118b6c37954d52f98b8a337148d6
+  caveman99/ESP32 Codec2@^1.0.1
+
+lib_ignore = 
+  segger_rtt
+  ESP32 BLE Arduino
+
+; customize the partition table
+; http://docs.platformio.org/en/latest/platforms/espressif32.html#partition-tables
+board_build.partitions = partition-table.csv
+

src/modules/SerialModule.cpp

@@ -82,7 +82,7 @@ SerialModuleRadio::SerialModuleRadio() : MeshModule("SerialModuleRadio")
 
 int32_t SerialModule::runOnce()
 {
-#if (defined(ARCH_ESP32) || defined(ARCH_NRF52)) && !defined(TTGO_T_ECHO)
+#if (defined(ARCH_ESP32) || defined(ARCH_NRF52)) && !defined(TTGO_T_ECHO) && !defined(CONFIG_IDF_TARGET_ESP32S2)
     /*
         Uncomment the preferences below if you want to use the module
         without having to configure it from the PythonAPI or WebUI.
@@ -235,7 +235,7 @@ void SerialModuleRadio::sendPayload(NodeNum dest, bool wantReplies)
 
 ProcessMessage SerialModuleRadio::handleReceived(const MeshPacket &mp)
 {
-#if (defined(ARCH_ESP32) || defined(ARCH_NRF52)) && !defined(TTGO_T_ECHO)
+#if (defined(ARCH_ESP32) || defined(ARCH_NRF52)) && !defined(TTGO_T_ECHO) && !defined(CONFIG_IDF_TARGET_ESP32S2)
     if (moduleConfig.serial.enabled) {
 
         auto &p = mp.decoded;

src/platform/esp32/main-esp32.cpp

@@ -3,7 +3,9 @@
 #include "esp_task_wdt.h"
 #include "main.h"
 
+#if !defined(CONFIG_IDF_TARGET_ESP32S2)
 #include "nimble/NimbleBluetooth.h"
+#endif
 #include "BleOta.h"
 #include "mesh/http/WiFiAPClient.h"
 
@@ -16,13 +18,9 @@
 #include <nvs_flash.h>
 #include "soc/rtc.h"
 
+#if !defined(CONFIG_IDF_TARGET_ESP32S2)
 NimbleBluetooth *nimbleBluetooth;
 
-void getMacAddr(uint8_t *dmac)
-{
-    assert(esp_efuse_mac_get_default(dmac) == ESP_OK);
-}
-
 void setBluetoothEnable(bool on) {
 
     if (!isWifiAvailable() && config.bluetooth.enabled == true) {
@@ -36,6 +34,15 @@ void setBluetoothEnable(bool on) {
         }
     }
 }
+#else
+void setBluetoothEnable(bool on) { }
+void updateBatteryLevel(uint8_t level) { }
+#endif
+
+void getMacAddr(uint8_t *dmac)
+{
+    assert(esp_efuse_mac_get_default(dmac) == ESP_OK);
+}
 
 #ifdef HAS_32768HZ
 #define CALIBRATE_ONE(cali_clk) calibrate_one(cali_clk, #cali_clk)

src/sleep.cpp

@@ -300,6 +300,8 @@ void enableModemSleep()
 
 #if CONFIG_IDF_TARGET_ESP32S3
     esp32_config.max_freq_mhz = CONFIG_ESP32S3_DEFAULT_CPU_FREQ_MHZ;
+#elif CONFIG_IDF_TARGET_ESP32S2
+    esp32_config.max_freq_mhz = CONFIG_ESP32S2_DEFAULT_CPU_FREQ_MHZ;
 #else
     esp32_config.max_freq_mhz = CONFIG_ESP32_DEFAULT_CPU_FREQ_MHZ;
 #endif