Apply SX1262 register 0x8B5 patch for improved GC1109 RX sensitivity

.gitignore

@@ -33,6 +33,7 @@ __pycache__
 *~
 
 venv/
+.venv/
 release/
 .vscode/extensions.json
 /compile_commands.json

src/mesh/SX126xInterface.cpp

@@ -194,6 +194,17 @@ template <typename T> bool SX126xInterface<T>::init()
         LOG_INFO("Set RX gain to power saving mode (boosted mode off); result: %d", result);
     }
 
+#ifdef USE_GC1109_PA
+    // Undocumented SX1262 register patch recommended by Heltec/Semtech for improved RX sensitivity
+    // on boards with the GC1109 FEM. Sets bit 0 of register 0x8B5.
+    // Reference: https://github.com/meshcore-dev/MeshCore/pull/1398
+    if (module.SPIsetRegValue(0x8B5, 0x01, 0, 0) == RADIOLIB_ERR_NONE) {
+        LOG_INFO("Applied SX1262 register 0x8B5 patch for GC1109 RX improvement");
+    } else {
+        LOG_WARN("Failed to apply SX1262 register 0x8B5 patch for GC1109");
+    }
+#endif
+
 #if 0
     // Read/write a register we are not using (only used for FSK mode) to test SPI comms
     uint8_t crcLSB = 0;