Add --udc argument

Allow the user to specify which udc controller to use.
DWC2 / usb-gadget / fe98000.usb is not the only one available.

Author: KreAch3R

README.md

@@ -131,6 +131,7 @@ OPTIONS:
     -l, --logfile <LOGFILE>           Log file path [default: /var/log/aa-proxy-rs.log]
     -s, --stats-interval <SECONDS>    Interval of showing data transfer statistics (0 = disabled)
                                       [default: 0]
+    -u, --udc <UDCNAME>               Specify UDC Controller to use
     -V, --version                     Print version information
 ```
 Most options are self explanatory, but these needs some more attention:<br>

src/main.rs

@@ -57,6 +57,14 @@ struct Args {
     /// Interval of showing data transfer statistics (0 = disabled)
     #[clap(short, long, value_name = "SECONDS", default_value_t = 0)]
     stats_interval: u16,
+
+    /// UDC Controller name
+    #[clap(
+        short,
+        long
+    )]
+    udc: Option<String>,
+    
 }
 
 fn logging_init(debug: bool, log_path: &PathBuf) {
@@ -106,6 +114,7 @@ async fn tokio_main(
     advertise: bool,
     legacy: bool,
     connect: Option<Address>,
+    udc: Option<String>,
     need_restart: Arc<Notify>,
     tcp_start: Arc<Notify>,
 ) {
@@ -117,7 +126,7 @@ async fn tokio_main(
         std::thread::spawn(|| uevent_listener(accessory_started_cloned));
     }
 
-    let mut usb = UsbGadgetState::new(legacy);
+    let mut usb = UsbGadgetState::new(legacy, udc);
     loop {
         if let Err(e) = usb.init() {
             error!("{} 🔌 USB init error: {}", NAME, e);
@@ -203,6 +212,7 @@ fn main() {
             args.advertise,
             args.legacy,
             args.connect,
+            args.udc,
             need_restart,
             tcp_start,
         )

src/usb_gadget.rs

@@ -53,27 +53,38 @@ pub struct UsbGadgetState {
     configfs_path: PathBuf,
     udc_name: String,
     legacy: bool,
+    udc: Option<String>,
 }
 
 impl UsbGadgetState {
-    pub fn new(legacy: bool) -> UsbGadgetState {
+    pub fn new(legacy: bool, udc: Option<String>) -> UsbGadgetState {
         let mut state = UsbGadgetState {
             configfs_path: PathBuf::from("/sys/kernel/config/usb_gadget"),
             udc_name: String::new(),
             legacy,
+            udc
         };
 
-        let udc_dir = PathBuf::from("/sys/class/udc");
-        if let Ok(entries) = fs::read_dir(&udc_dir) {
-            for entry in entries {
-                if let Ok(entry) = entry {
-                    info!("Using UDC: {:?}", entry.file_name());
-                    if let Ok(fname) = entry.file_name().into_string() {
-                        state.udc_name.push_str(fname.as_str());
-                        break;
+        // If UDC argument is passed, use it, otherwise check sys
+        match state.udc {
+            None => {
+                let udc_dir = PathBuf::from("/sys/class/udc");
+                if let Ok(entries) = fs::read_dir(&udc_dir) {
+                    for entry in entries {
+                        if let Ok(entry) = entry {
+                            info!("Using UDC: {:?}", entry.file_name());
+                            if let Ok(fname) = entry.file_name().into_string() {
+                                state.udc_name.push_str(fname.as_str());
+                                break;
+                            }
+                        }
                     }
                 }
             }
+            Some(ref udcname) => {
+                info!("Using UDC: {:?}", udcname);
+                state.udc_name.push_str(&udcname);
+            }
         }
 
         return state;