From 500cc894b51f74f3c8b8d8d15a1bccab376645c0 Mon Sep 17 00:00:00 2001
From: Theo Arends <11044339+arendst@users.noreply.github.com>
Date: Mon, 11 Apr 2022 16:40:41 +0200
Subject: [PATCH] Fix USB CDC on ESP32C3

Fix USB CDC on ESP32C3 (https://github.com/espressif/arduino-esp32/issues/6264)
---
 tasmota/support_wifi.ino | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/tasmota/support_wifi.ino b/tasmota/support_wifi.ino
index d271de1cc..04d44e78b 100644
--- a/tasmota/support_wifi.ino
+++ b/tasmota/support_wifi.ino
@@ -116,7 +116,18 @@ void WifiConfig(uint8_t type)
   }
 }
 
+#ifdef CONFIG_IDF_TARGET_ESP32C3
+  // https://github.com/espressif/arduino-esp32/issues/6264#issuecomment-1040147331
+  // There's an include for this but it doesn't define the function if it doesn't think it needs it, so manually declare the function
+extern "C" void phy_bbpll_en_usb(bool en);
+#endif  // CONFIG_IDF_TARGET_ESP32C3
+
 void WifiSetMode(WiFiMode_t wifi_mode) {
+#ifdef CONFIG_IDF_TARGET_ESP32C3
+  // https://github.com/espressif/arduino-esp32/issues/6264#issuecomment-1094376906
+  // This brings the USB serial-jtag back to life. Suggest doing this immediately after wifi startup.
+  phy_bbpll_en_usb(true);
+#endif  // CONFIG_IDF_TARGET_ESP32C3
   if (WiFi.getMode() == wifi_mode) { return; }
 
   if (wifi_mode != WIFI_OFF) {