add additional permissions so we can use USB api

js/stm32dfu.js

@@ -53,6 +53,12 @@ var STM32DFU_protocol = function() {
         dfuUPLOAD_IDLE:         9, // The device is processing an upload operation. Expecting DFU_UPLOAD requests.
         dfuERROR:               10 // An error has occurred. Awaiting the DFU_CLRSTATUS request.
     };
+
+    this.usbDevices = {
+        F3DiscoveryDFU: {'vendorId': 1155, 'productId': 57105}
+    };
+
+    this.usbPermissions = {permissions: [{'usbDevices': [this.usbDevices.F3DiscoveryDFU]}]};
 };
 
 STM32DFU_protocol.prototype.openDevice = function(callback) {

manifest.json

@@ -23,6 +23,7 @@
         "https://*.github.com/",
         "https://*.githubusercontent.com/",
         "serial",
+        "usb",
         "storage",
         "fileSystem",
         "fileSystem.write",
@@ -30,6 +31,12 @@
         "notifications"
     ],
 
+    "optional_permissions": [
+        {"usbDevices": [
+            {"vendorId": 1155, "productId": 57105}
+        ]}
+    ],
+
     "icons": {
         "128": "images/icon_128.png"
     }