feat(hid): 支持 CH9329 + OTG 组合模式

CH9329 负责键鼠，OTG 提供虚拟媒体、USB 网络和音频；分别配置设备、报告运行状态，并在 OTG 配置变更和回滚时保留未变化的 CH9329 实例。补齐双设备校验、串口冲突检查、初始化引导和功能入口，修复组合模式下鼠标兼容选项缺失。验证：独立功能版本的 591 项 Rust 库测试、前端生产构建、3 项引导逻辑测试及 2 组浏览器回归通过。未进行目标 KVM 硬件验证。
2026-10-28 08:20:49 +08:00 · 2026-10-26 14:33:38 +08:00
parent b4161f3534
commit f303a8cb2f
30 changed files with 718 additions and 225 deletions
--- a/src/config/schema/hid.rs
+++ b/src/config/schema/hid.rs
@@ -56,11 +56,37 @@ impl BluetoothHidConfig {
 pub enum HidBackend {
    Otg,
    Ch9329,
+    #[serde(rename = "ch9329_otg")]
+    Ch9329Otg,
    Bluetooth,
    #[default]
    None,
 }

+impl HidBackend {
+    pub fn uses_ch9329(&self) -> bool {
+        matches!(self, Self::Ch9329 | Self::Ch9329Otg)
+    }
+
+    pub fn uses_otg_hid(&self) -> bool {
+        matches!(self, Self::Otg)
+    }
+
+    pub fn supports_otg_functions(&self) -> bool {
+        matches!(self, Self::Otg | Self::Ch9329Otg)
+    }
+
+    pub fn as_str(&self) -> &'static str {
+        match self {
+            Self::Otg => "otg",
+            Self::Ch9329 => "ch9329",
+            Self::Ch9329Otg => "ch9329_otg",
+            Self::Bluetooth => "bluetooth",
+            Self::None => "none",
+        }
+    }
+}
+
 #[typeshare]
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
 pub struct OtgDescriptorConfig {
@@ -141,6 +167,15 @@ pub struct OtgHidFunctions {
 }

 impl OtgHidFunctions {
+    pub fn disabled() -> Self {
+        Self {
+            keyboard: false,
+            mouse_relative: false,
+            mouse_absolute: false,
+            consumer: false,
+        }
+    }
+
    pub fn full() -> Self {
        Self {
            keyboard: true,
@@ -264,15 +299,49 @@ impl HidConfig {
    }

    pub fn effective_otg_keyboard_leds(&self) -> bool {
-        self.otg_keyboard_leds && self.effective_otg_functions().keyboard
+        self.otg_keyboard_leds && self.constrained_otg_functions().keyboard
    }

    pub fn constrained_otg_functions(&self) -> OtgHidFunctions {
-        self.effective_otg_functions()
+        if self.backend.uses_otg_hid() {
+            self.effective_otg_functions()
+        } else {
+            OtgHidFunctions::disabled()
+        }
+    }
+
+    pub fn validate_platform(&self) -> crate::error::Result<()> {
+        if self.backend == HidBackend::Ch9329Otg && !cfg!(target_os = "linux") {
+            return Err(crate::error::AppError::BadRequest(
+                "CH9329 + OTG requires Linux with a USB device controller".into(),
+            ));
+        }
+        Ok(())
+    }
+
+    pub fn validate_composite_selection(&self) -> crate::error::Result<()> {
+        if self.backend != HidBackend::Ch9329Otg {
+            return Ok(());
+        }
+        if self.ch9329_port.trim().is_empty()
+            || ![9600, 19200, 38400, 57600, 115200].contains(&self.ch9329_baudrate)
+        {
+            return Err(crate::error::AppError::BadRequest(
+                "CH9329 + OTG requires a serial port and a supported baudrate".into(),
+            ));
+        }
+        if !self.otg_udc.as_ref().is_some_and(|udc| {
+            !udc.trim().is_empty() && !udc.contains('/') && udc != "." && udc != ".."
+        }) {
+            return Err(crate::error::AppError::BadRequest(
+                "CH9329 + OTG requires an explicit USB device controller".into(),
+            ));
+        }
+        Ok(())
    }

    pub fn validate_otg_functions(&self) -> crate::error::Result<()> {
-        if self.backend != HidBackend::Otg {
+        if !self.backend.uses_otg_hid() {
            return Ok(());
        }

@@ -293,7 +362,7 @@ impl HidConfig {

    #[inline]
    pub fn resolved_otg_udc(&self) -> Option<String> {
-        if self.backend != HidBackend::Otg {
+        if !self.backend.supports_otg_functions() {
            return None;
        }
        self.otg_udc
@@ -301,6 +370,9 @@ impl HidConfig {
            .map(|s| s.trim().to_string())
            .filter(|s| !s.is_empty())
            .or_else(|| {
+                if !self.backend.uses_otg_hid() {
+                    return None;
+                }
                #[cfg(unix)]
                {
                    crate::otg::OtgGadgetManager::find_udc()
@@ -316,6 +388,53 @@ impl HidConfig {
 #[cfg(test)]
 mod bluetooth_tests {
    use super::*;
+    #[test]
+    fn composite_mode_preserves_usb_functions_and_saved_otg_profile() {
+        let mut config = crate::config::AppConfig::default();
+        config.hid.backend = HidBackend::Ch9329Otg;
+        config.hid.otg_profile = OtgHidProfile::LegacyKeyboard;
+        config.hid.otg_keyboard_leds = true;
+        config.hid.mouse_macos_drag = true;
+        config.msd.enabled = true;
+        config.otg_network.enabled = true;
+        config.uac.enabled = true;
+        config.enforce_invariants();
+        assert!(config.msd.enabled && config.otg_network.enabled && config.uac.enabled);
+        assert!(config.hid.constrained_otg_functions().is_empty());
+        assert!(!config.hid.effective_otg_keyboard_leds());
+        assert!(config.hid.validate_otg_functions().is_ok());
+        let saved = serde_json::to_value(&config.hid).unwrap();
+        assert_eq!(saved["backend"], "ch9329_otg");
+        assert_eq!(saved["otg_profile"], "legacy_keyboard");
+        config.hid = serde_json::from_value(saved).unwrap();
+        config.hid.backend = HidBackend::Otg;
+        assert!(config.hid.constrained_otg_functions().keyboard);
+        assert!(config.hid.effective_otg_keyboard_leds());
+        config.hid.backend = HidBackend::Ch9329;
+        config.enforce_invariants();
+        assert!(!config.msd.enabled && !config.otg_network.enabled && !config.uac.enabled);
+    }
+
+    #[test]
+    fn composite_selection_requires_both_devices_without_auto_udc_fallback() {
+        let mut config = HidConfig {
+            backend: HidBackend::Ch9329Otg,
+            ..Default::default()
+        };
+        assert!(config.validate_composite_selection().is_err());
+        assert!(config.resolved_otg_udc().is_none());
+        config.otg_udc = Some("test.udc".into());
+        assert!(config.validate_composite_selection().is_ok());
+        assert_eq!(config.resolved_otg_udc().as_deref(), Some("test.udc"));
+        for udc in ["", "../other", "/sys/class/udc/test", ".."] {
+            config.otg_udc = Some(udc.into());
+            assert!(config.validate_composite_selection().is_err());
+        }
+        config.otg_udc = Some("test.udc".into());
+        config.ch9329_port.clear();
+        assert!(config.validate_composite_selection().is_err());
+    }
+
    #[test]
    fn mouse_compatibility_defaults_alias_and_otg_validation() {
        let defaults: HidConfig = serde_json::from_str(r#"{"backend":"otg"}"#).unwrap();
--- a/src/config/schema/mod.rs
+++ b/src/config/schema/mod.rs
@@ -51,7 +51,7 @@ pub struct AppConfig {

 impl AppConfig {
    pub fn enforce_invariants(&mut self) {
-        if self.hid.backend != HidBackend::Otg {
+        if !self.hid.backend.supports_otg_functions() {
            self.msd.enabled = false;
            self.otg_network.enabled = false;
            self.uac.enabled = false;
--- a/src/hid/backend.rs
+++ b/src/hid/backend.rs
@@ -37,6 +37,27 @@ pub enum HidBackendType {
    None,
 }

+impl From<&crate::config::HidConfig> for HidBackendType {
+    fn from(config: &crate::config::HidConfig) -> Self {
+        use crate::config::HidBackend;
+        match config.backend {
+            HidBackend::Otg => Self::Otg {
+                macos_drag: config.mouse_macos_drag,
+            },
+            HidBackend::Ch9329 | HidBackend::Ch9329Otg => Self::Ch9329 {
+                port: config.ch9329_port.clone(),
+                baud_rate: config.ch9329_baudrate,
+                hybrid_mouse: config.ch9329_hybrid_mouse,
+                macos_drag: config.mouse_macos_drag,
+            },
+            HidBackend::Bluetooth => Self::Bluetooth {
+                config: config.bluetooth.clone(),
+            },
+            HidBackend::None => Self::None,
+        }
+    }
+}
+
 impl HidBackendType {
    pub fn name_str(&self) -> &str {
        match self {
--- a/src/hid/mod.rs
+++ b/src/hid/mod.rs
@@ -767,6 +767,60 @@ fn merge_pending_move(pending: &mut Option<MouseEvent>, event: MouseEvent) {
 #[cfg(test)]
 mod queue_tests {
    use super::*;
+    #[cfg(unix)]
+    #[tokio::test]
+    async fn composite_otg_updates_and_rollback_preserve_hid_instance() {
+        let mut old = crate::config::AppConfig::default();
+        old.hid.backend = crate::config::HidBackend::Ch9329;
+        old.enforce_invariants();
+        let otg = Arc::new(OtgService::new());
+        let controller = Arc::new(HidController::new(
+            HidBackendType::from(&old.hid),
+            Some(otg.clone()),
+        ));
+        let pressed = Arc::new(AtomicBool::new(true));
+        let (runtime, _) = tokio::sync::watch::channel(());
+        let backend: Arc<dyn HidBackend> = Arc::new(TestBackend {
+            pressed: pressed.clone(),
+            reset_done: Arc::new(tokio::sync::Notify::new()),
+            runtime,
+        });
+        *controller.backend.write().await = Some(backend.clone());
+        let data = tempfile::tempdir().unwrap();
+        let coordinator = crate::runtime::UsbCoordinator::new(
+            controller.clone(),
+            otg,
+            Arc::new(RwLock::new(None)),
+            Arc::new(RwLock::new(None)),
+            Arc::new(EventBus::new()),
+            data.path().into(),
+        );
+        let mut new = old.clone();
+        new.hid.backend = crate::config::HidBackend::Ch9329Otg;
+        new.hid.otg_udc = Some("test.udc".into());
+        new.hid.otg_descriptor.product = "Advanced USB".into();
+        new.hid.otg_keyboard_leds = true;
+        coordinator.apply_config(&old, &new).await.unwrap();
+        assert!(Arc::ptr_eq(
+            controller.backend.read().await.as_ref().unwrap(),
+            &backend
+        ));
+        coordinator.apply_config(&new, &old).await.unwrap();
+        assert!(Arc::ptr_eq(
+            controller.backend.read().await.as_ref().unwrap(),
+            &backend
+        ));
+        assert!(pressed.load(Ordering::Acquire));
+        // Invalid OTG configuration must not touch the healthy input backend.
+        new.uac.enabled = true;
+        new.uac.sample_rate = 8000;
+        assert!(coordinator.apply_config(&old, &new).await.is_err());
+        assert!(Arc::ptr_eq(
+            controller.backend.read().await.as_ref().unwrap(),
+            &backend
+        ));
+    }
+
    #[tokio::test]
    async fn screen_resolution_updates_backend_and_retains_valid_dimensions() {
        #[cfg(unix)]
--- a/src/otg/self_check.rs
+++ b/src/otg/self_check.rs
@@ -149,8 +149,11 @@ fn detect_libcomposite_available(gadget_root: &std::path::Path) -> bool {

 /// OTG self-check status for troubleshooting USB gadget issues
 pub fn run(config: &crate::config::AppConfig) -> OtgSelfCheckResponse {
-    let hid_backend_is_otg = matches!(config.hid.backend, crate::config::HidBackend::Otg);
-    let gadget_expected = hid_backend_is_otg || config.msd.enabled || config.otg_network.enabled;
+    let hid_backend_is_otg = config.hid.backend.uses_otg_hid();
+    let gadget_expected = hid_backend_is_otg
+        || config.msd.enabled
+        || config.otg_network.enabled
+        || config.uac.enabled;
    let mut checks = Vec::new();

    let build_response = |checks: Vec<OtgSelfCheckItem>,
@@ -173,7 +176,7 @@ pub fn run(config: &crate::config::AppConfig) -> OtgSelfCheckResponse {
            overall_ok: error_count == 0,
            error_count,
            warning_count,
-            hid_backend: format!("{:?}", config.hid.backend).to_lowercase(),
+            hid_backend: config.hid.backend.as_str().to_string(),
            selected_udc,
            bound_udc,
            udc_state,
@@ -415,7 +418,7 @@ pub fn run(config: &crate::config::AppConfig) -> OtgSelfCheckResponse {
                OtgSelfCheckLevel::Warn
            },
            "Check one-kvm gadget presence",
-            Some("Enable OTG HID, MSD, or USB Ethernet to create the one-kvm gadget"),
+            Some("Enable OTG HID, MSD, USB Ethernet, or USB audio to create the one-kvm gadget"),
            Some(one_kvm_path.display().to_string()),
        );
    }
@@ -459,7 +462,7 @@ pub fn run(config: &crate::config::AppConfig) -> OtgSelfCheckResponse {
                false,
                OtgSelfCheckLevel::Warn,
                "Check one-kvm UDC binding",
-                Some("Ensure HID/MSD is enabled and initialized successfully"),
+                Some("Ensure an OTG function is enabled and initialized successfully"),
                Some(one_kvm_udc_path.display().to_string()),
            );
        } else {
@@ -494,18 +497,19 @@ pub fn run(config: &crate::config::AppConfig) -> OtgSelfCheckResponse {
            })
            .cloned()
            .collect::<Vec<_>>();
-        if hid_functions.is_empty() {
+        let hid_functions_ok = hid_backend_is_otg != hid_functions.is_empty();
+        if !hid_functions_ok {
            push_otg_check(
                &mut checks,
                "hid_functions_present",
                false,
-                if hid_backend_is_otg {
-                    OtgSelfCheckLevel::Error
+                OtgSelfCheckLevel::Error,
+                "Check OTG HID function selection",
+                Some(if hid_backend_is_otg {
+                    "Check OTG HID config and enable at least one HID function"
                } else {
-                    OtgSelfCheckLevel::Warn
-                },
-                "Check HID function creation",
-                Some("Check OTG HID config and enable at least one HID function"),
+                    "OTG HID must be disabled when input is handled by another backend"
+                }),
                Some(functions_path.display().to_string()),
            );
        } else {
@@ -514,7 +518,7 @@ pub fn run(config: &crate::config::AppConfig) -> OtgSelfCheckResponse {
                "hid_functions_present",
                true,
                OtgSelfCheckLevel::Info,
-                "Check HID function creation",
+                "Check OTG HID function selection",
                None::<String>,
                Some(functions_path.display().to_string()),
            );
@@ -569,9 +573,13 @@ pub fn run(config: &crate::config::AppConfig) -> OtgSelfCheckResponse {
                                .map(|name| name.to_string_lossy().to_string())
                        })
                        .is_some_and(|name| {
-                            name == "okvm-br0" || name == config.otg_network.bridge_interface
+                            name == "okvm-br0"
+                                || name == config.otg_network.bridge_interface
                                || (config.otg_network.bridge_interface.is_empty()
-                                    && std::path::Path::new("/sys/class/net").join(name).join("bridge").is_dir())
+                                    && std::path::Path::new("/sys/class/net")
+                                        .join(name)
+                                        .join("bridge")
+                                        .is_dir())
                        });
                    push_otg_check(
                        &mut checks,
@@ -843,7 +851,7 @@ pub fn run(config: &crate::config::AppConfig) -> OtgSelfCheckResponse {
        overall_ok: error_count == 0,
        error_count,
        warning_count,
-        hid_backend: format!("{:?}", config.hid.backend).to_lowercase(),
+        hid_backend: config.hid.backend.as_str().to_string(),
        selected_udc,
        bound_udc,
        udc_state,
--- a/src/otg/service.rs
+++ b/src/otg/service.rs
@@ -8,8 +8,7 @@ use super::bridge::NetworkBridgeRuntime;
 use super::manager::{wait_for_hid_devices, GadgetDescriptor, OtgGadgetManager};
 use super::msd::{MsdFunction, MsdInquiryStrings, MsdLunConfig};
 use crate::config::{
-    HidBackend, HidConfig, MsdConfig, OtgDescriptorConfig, OtgHidFunctions, OtgNetworkConfig,
-    UacConfig,
+    HidConfig, MsdConfig, OtgDescriptorConfig, OtgHidFunctions, OtgNetworkConfig, UacConfig,
 };
 use crate::error::{AppError, Result};

@@ -40,6 +39,17 @@ pub struct OtgNetworkStatus {
    pub error: Option<String>,
 }

+#[typeshare]
+#[derive(Debug, Clone, serde::Serialize)]
+pub struct OtgRuntimeStatus {
+    pub enabled: bool,
+    pub health: OtgRuntimeHealth,
+    pub gadget_active: bool,
+    pub udc: Option<String>,
+    pub udc_state: Option<String>,
+    pub error: Option<String>,
+}
+
 impl HidDevicePaths {
    pub fn existing_paths(&self) -> Vec<PathBuf> {
        [
@@ -93,7 +103,7 @@ impl OtgDesiredState {
        network.validate()?;
        uac.validate()?;
        msd.validate()?;
-        let hid_functions = if hid.backend == HidBackend::Otg {
+        let hid_functions = if hid.backend.uses_otg_hid() {
            let functions = hid.constrained_otg_functions();
            Some(functions)
        } else {
@@ -107,7 +117,13 @@ impl OtgDesiredState {
                .as_ref()
                .map(|value| value.trim().to_string())
                .filter(|value| !value.is_empty())
-                .or_else(OtgGadgetManager::find_udc)
+                .or_else(|| {
+                    if hid.backend.uses_ch9329() {
+                        None
+                    } else {
+                        OtgGadgetManager::find_udc()
+                    }
+                })
        } else {
            None
        };
@@ -249,6 +265,25 @@ impl OtgService {
        }
    }

+    pub async fn runtime_status(&self, enabled: bool) -> OtgRuntimeStatus {
+        let state = self.state.read().await;
+        let udc_state = state.configured_udc.as_ref().and_then(|udc| {
+            // Only UDC names, never a path supplied through a configuration file.
+            if udc.contains('/') || udc == "." || udc == ".." {
+                return None;
+            }
+            crate::utils::read_trimmed(&PathBuf::from(format!("/sys/class/udc/{udc}/state")))
+        });
+        OtgRuntimeStatus {
+            enabled,
+            health: state.health,
+            gadget_active: state.gadget_active,
+            udc: state.configured_udc.clone(),
+            udc_state,
+            error: state.error.clone(),
+        }
+    }
+
    pub async fn apply_config(
        &self,
        hid: &HidConfig,
@@ -687,6 +722,38 @@ impl From<&OtgDescriptorConfig> for GadgetDescriptor {
 #[cfg(test)]
 mod tests {
    use super::*;
+    use crate::config::HidBackend;
+
+    #[test]
+    fn composite_gadget_supports_every_advanced_function_combination_without_hid() {
+        let hid = HidConfig {
+            backend: HidBackend::Ch9329Otg,
+            otg_udc: Some("test.udc".into()),
+            otg_keyboard_leds: true,
+            ..Default::default()
+        };
+        for mask in 0..8 {
+            let msd = MsdConfig {
+                enabled: mask & 1 != 0,
+                ..Default::default()
+            };
+            let network = OtgNetworkConfig {
+                enabled: mask & 2 != 0,
+                ..Default::default()
+            };
+            let uac = UacConfig {
+                enabled: mask & 4 != 0,
+                ..Default::default()
+            };
+            let desired = OtgDesiredState::from_config(&hid, &msd, &network, &uac).unwrap();
+            assert!(!desired.hid_enabled());
+            assert!(!desired.keyboard_leds);
+            assert_eq!(desired.msd_enabled, msd.enabled);
+            assert_eq!(desired.network_enabled(), network.enabled);
+            assert_eq!(desired.uac.enabled, uac.enabled);
+            assert_eq!(desired.udc.is_some(), mask != 0);
+        }
+    }

    #[test]
    fn service_new_and_availability_probe() {
--- a/src/platform/linux.rs
+++ b/src/platform/linux.rs
@@ -10,7 +10,7 @@ pub fn capabilities() -> PlatformCapabilities {
        encoder: FeatureCapability::available([
            "software", "vaapi", "nvenc", "qsv", "amf", "rkmpp", "v4l2m2m",
        ]),
-        hid: FeatureCapability::available(["otg", "ch9329", "bluetooth", "none"]),
+        hid: FeatureCapability::available(["otg", "ch9329", "ch9329_otg", "bluetooth", "none"]),
        atx: FeatureCapability::available(["gpio", "usb_relay", "serial", "wol", "none"]),
        msd: FeatureCapability::available(["configfs"]),
        otg: FeatureCapability::available(["configfs"]),
--- a/src/runtime/builder.rs
+++ b/src/runtime/builder.rs
@@ -6,7 +6,7 @@ use tokio::sync::broadcast;
 use crate::atx::AtxController;
 use crate::audio::{AudioController, AudioControllerConfig, AudioQuality};
 use crate::auth::{SessionStore, TwoFactorService, UserStore};
-use crate::config::{self, AppConfig, ConfigStore};
+use crate::config::{AppConfig, ConfigStore};
 use crate::db::{open_database_pool, DatabasePool};
 use crate::events::EventBus;
 use crate::extensions::ExtensionManager;
@@ -81,6 +81,7 @@ impl RuntimeBuilder {
            web_overrides,
        } = self;
        let (db, config_store, mut config) = load_runtime_config(&data_dir).await?;
+        config.hid.validate_platform()?;
        web_overrides.apply(&mut config);

        let sessions = SessionStore::new(config.auth.session_timeout_secs as i64);
@@ -400,26 +401,13 @@ async fn build_otg(config: &AppConfig) -> Arc<OtgService> {
        .await
    {
        tracing::warn!("Failed to apply OTG config: {}", error);
+        service.mark_degraded(error.to_string()).await;
    }
    service
 }

 fn hid_backend_type(config: &AppConfig) -> HidBackendType {
-    match config.hid.backend {
-        config::HidBackend::Otg => HidBackendType::Otg {
-            macos_drag: config.hid.mouse_macos_drag,
-        },
-        config::HidBackend::Ch9329 => HidBackendType::Ch9329 {
-            port: config.hid.ch9329_port.clone(),
-            baud_rate: config.hid.ch9329_baudrate,
-            hybrid_mouse: config.hid.ch9329_hybrid_mouse,
-            macos_drag: config.hid.mouse_macos_drag,
-        },
-        config::HidBackend::None => HidBackendType::None,
-        config::HidBackend::Bluetooth => HidBackendType::Bluetooth {
-            config: config.hid.bluetooth.clone(),
-        },
-    }
+    HidBackendType::from(&config.hid)
 }

 #[cfg(unix)]
--- a/src/runtime/usb.rs
+++ b/src/runtime/usb.rs
@@ -51,24 +51,31 @@ impl UsbCoordinator {
    }

    pub async fn apply_config(&self, old_config: &AppConfig, new_config: &AppConfig) -> Result<()> {
+        new_config.hid.validate_platform()?;
        #[cfg(unix)]
        {
            let transitioning_away_from_otg = old_config.hid.backend == HidBackend::Otg
                && new_config.hid.backend != HidBackend::Otg;
-            let hid_unchanged = old_config.hid == new_config.hid;
-            let gadget_rebuilt = old_config.msd != new_config.msd
-                || old_config.otg_network != new_config.otg_network
-                || old_config.uac != new_config.uac
-                || old_config.hid.otg_udc != new_config.hid.otg_udc
-                || old_config.hid.otg_descriptor != new_config.hid.otg_descriptor
-                || old_config.hid.backend != new_config.hid.backend
-                || old_config.hid.constrained_otg_functions()
-                    != new_config.hid.constrained_otg_functions()
-                || old_config.hid.effective_otg_keyboard_leds()
-                    != new_config.hid.effective_otg_keyboard_leds();
+            let hid_unchanged = !hid_requires_reload(&old_config.hid, &new_config.hid);
+            let gadget_rebuilt = crate::otg::service::OtgDesiredState::from_config(
+                &old_config.hid,
+                &old_config.msd,
+                &old_config.otg_network,
+                &old_config.uac,
+            )? != crate::otg::service::OtgDesiredState::from_config(
+                &new_config.hid,
+                &new_config.msd,
+                &new_config.otg_network,
+                &new_config.uac,
+            )?;
            let restart_uac =
                old_config.uac != new_config.uac || (new_config.uac.enabled && gadget_rebuilt);

+            if gadget_rebuilt {
+                // This is a no-op for CH9329, including the composite mode.
+                self.hid.prepare_otg_rebuild().await?;
+            }
+
            if restart_uac {
                let playback = self.uac_playback.write().await.take();
                if let Some(playback) = playback {
@@ -167,29 +174,11 @@ impl UsbCoordinator {
        uac_config: &UacConfig,
        options: ConfigApplyOptions,
    ) -> Result<()> {
+        new_config.validate_platform()?;
        new_config.validate_otg_functions()?;
        new_config.bluetooth.validate()?;

-        let descriptor_changed = old_config.otg_descriptor != new_config.otg_descriptor;
-        let hid_functions_changed =
-            old_config.constrained_otg_functions() != new_config.constrained_otg_functions();
-        let keyboard_leds_changed =
-            old_config.effective_otg_keyboard_leds() != new_config.effective_otg_keyboard_leds();
-        let mouse_compatibility_changed = old_config.ch9329_hybrid_mouse
-            != new_config.ch9329_hybrid_mouse
-            || old_config.mouse_macos_drag != new_config.mouse_macos_drag;
-
-        if old_config.backend == new_config.backend
-            && old_config.ch9329_port == new_config.ch9329_port
-            && old_config.ch9329_baudrate == new_config.ch9329_baudrate
-            && old_config.bluetooth == new_config.bluetooth
-            && !mouse_compatibility_changed
-            && old_config.otg_udc == new_config.otg_udc
-            && !descriptor_changed
-            && !hid_functions_changed
-            && !keyboard_leds_changed
-            && !options.force
-        {
+        if !hid_requires_reload(old_config, new_config) && !options.force {
            tracing::info!("HID config unchanged, skipping reload");
            return Ok(());
        }
@@ -256,7 +245,7 @@ impl UsbCoordinator {
        options: ConfigApplyOptions,
    ) -> Result<()> {
        let old_enabled = old_config.enabled;
-        let new_enabled = new_config.enabled && hid_config.backend == HidBackend::Otg;
+        let new_enabled = new_config.enabled && hid_config.backend.supports_otg_functions();
        let directory_changed = old_config.msd_dir != new_config.msd_dir;
        let inquiry_changed = old_config.flash_inquiry_string != new_config.flash_inquiry_string
            || old_config.cdrom_inquiry_string != new_config.cdrom_inquiry_string;
@@ -309,28 +298,72 @@ impl UsbCoordinator {
 }

 fn hid_backend_type(config: &HidConfig) -> HidBackendType {
-    match config.backend {
-        HidBackend::Otg => HidBackendType::Otg {
-            macos_drag: config.mouse_macos_drag,
-        },
-        HidBackend::Ch9329 => HidBackendType::Ch9329 {
-            port: config.ch9329_port.clone(),
-            baud_rate: config.ch9329_baudrate,
-            hybrid_mouse: config.ch9329_hybrid_mouse,
-            macos_drag: config.mouse_macos_drag,
-        },
-        HidBackend::None => HidBackendType::None,
-        HidBackend::Bluetooth => HidBackendType::Bluetooth {
-            config: config.bluetooth.clone(),
-        },
-    }
+    HidBackendType::from(config)
 }

-fn hid_otg_config_changed(old_config: &HidConfig, new_config: &HidConfig) -> bool {
-    old_config.backend == HidBackend::Otg
-        || new_config.backend == HidBackend::Otg
-        || old_config.otg_udc != new_config.otg_udc
-        || old_config.otg_descriptor != new_config.otg_descriptor
-        || old_config.constrained_otg_functions() != new_config.constrained_otg_functions()
-        || old_config.effective_otg_keyboard_leds() != new_config.effective_otg_keyboard_leds()
+fn hid_requires_reload(old: &HidConfig, new: &HidConfig) -> bool {
+    HidBackendType::from(old) != HidBackendType::from(new)
+        || (new.backend.uses_otg_hid() && hid_otg_config_changed(old, new))
+}
+
+fn hid_otg_config_changed(old: &HidConfig, new: &HidConfig) -> bool {
+    old.backend.uses_otg_hid() != new.backend.uses_otg_hid()
+        || old.otg_udc != new.otg_udc
+        || old.otg_descriptor != new.otg_descriptor
+        || old.constrained_otg_functions() != new.constrained_otg_functions()
+        || old.effective_otg_keyboard_leds() != new.effective_otg_keyboard_leds()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn composite_otg_preferences_do_not_reload_ch9329_but_input_changes_do() {
+        let old = HidConfig {
+            backend: HidBackend::Ch9329Otg,
+            otg_udc: Some("first.udc".into()),
+            ..Default::default()
+        };
+        let mut new = old.clone();
+        new.otg_udc = Some("second.udc".into());
+        new.otg_descriptor.product = "Advanced USB".into();
+        new.otg_keyboard_leds = !old.otg_keyboard_leds;
+        new.otg_profile = crate::config::OtgHidProfile::LegacyKeyboard;
+        assert!(!hid_requires_reload(&old, &new));
+        assert!(!hid_requires_reload(&new, &old));
+
+        let input_changes: [fn(&mut HidConfig); 4] = [
+            |hid: &mut HidConfig| hid.ch9329_port.push('1'),
+            |hid: &mut HidConfig| hid.ch9329_baudrate = 115200,
+            |hid: &mut HidConfig| hid.ch9329_hybrid_mouse = !hid.ch9329_hybrid_mouse,
+            |hid: &mut HidConfig| hid.mouse_macos_drag = !hid.mouse_macos_drag,
+        ];
+        for change in input_changes {
+            let mut changed = old.clone();
+            change(&mut changed);
+            assert!(hid_requires_reload(&old, &changed));
+            assert!(hid_requires_reload(&changed, &old));
+        }
+    }
+
+    #[test]
+    fn composite_mode_switch_only_reloads_when_input_driver_changes() {
+        let composite = HidConfig {
+            backend: HidBackend::Ch9329Otg,
+            otg_udc: Some("test.udc".into()),
+            ..Default::default()
+        };
+        for (backend, reload) in [
+            (HidBackend::Ch9329, false),
+            (HidBackend::Otg, true),
+            (HidBackend::Bluetooth, true),
+            (HidBackend::None, true),
+        ] {
+            let mut other = composite.clone();
+            other.backend = backend;
+            assert_eq!(hid_requires_reload(&composite, &other), reload);
+            assert_eq!(hid_requires_reload(&other, &composite), reload);
+        }
+    }
 }
--- a/src/web/handlers/config/atx.rs
+++ b/src/web/handlers/config/atx.rs
@@ -2,7 +2,7 @@ use axum::{extract::State, Json};
 use std::sync::Arc;

 use crate::atx::AtxDriverType;
-use crate::config::{AtxConfig, HidBackend, HidConfig};
+use crate::config::{AtxConfig, HidConfig};
 use crate::error::{AppError, Result};
 use crate::state::AppState;

@@ -17,12 +17,13 @@ pub async fn update_atx_config(
    State(state): State<Arc<AppState>>,
    Json(req): Json<AtxConfigUpdate>,
 ) -> Result<Json<AtxConfig>> {
+    let _usb_guard = try_apply_lock(&state.config_apply_locks.otg, "otg")?;
+    let _apply_guard = try_apply_lock(&state.config_apply_locks.atx, "atx")?;
    let current_config = state.config.get();
    let old_atx_config = current_config.atx.clone();

    req.validate_with_current(&old_atx_config)?;

-    let _apply_guard = try_apply_lock(&state.config_apply_locks.atx, "atx")?;
    let mut merged_atx_config = old_atx_config.clone();
    req.apply_to(&mut merged_atx_config);
    validate_windows_atx_backends(&merged_atx_config)?;
@@ -56,8 +57,8 @@ fn validate_windows_atx_backends(atx: &AtxConfig) -> Result<()> {
    Ok(())
 }

-fn validate_serial_device_conflict(atx: &AtxConfig, hid: &HidConfig) -> Result<()> {
-    if hid.backend != HidBackend::Ch9329 {
+pub(super) fn validate_serial_device_conflict(atx: &AtxConfig, hid: &HidConfig) -> Result<()> {
+    if !hid.backend.uses_ch9329() {
        return Ok(());
    }
    let reserved = hid.ch9329_port.trim();
@@ -78,6 +79,7 @@ fn validate_serial_device_conflict(atx: &AtxConfig, hid: &HidConfig) -> Result<(
 #[cfg(test)]
 mod tests {
    use super::*;
+    use crate::config::HidBackend;

    #[test]
    fn test_validate_serial_device_conflict_rejects_ch9329_overlap() {
@@ -90,6 +92,8 @@ mod tests {
        hid.ch9329_port = "/dev/ttyUSB0".to_string();

        assert!(validate_serial_device_conflict(&atx, &hid).is_err());
+        hid.backend = HidBackend::Ch9329Otg;
+        assert!(validate_serial_device_conflict(&atx, &hid).is_err());
    }

    #[test]
--- a/src/web/handlers/config/otg.rs
+++ b/src/web/handlers/config/otg.rs
@@ -2,7 +2,7 @@ use axum::{extract::State, Json};
 use serde::Serialize;
 use typeshare::typeshare;

-use crate::config::{HidConfig, MsdConfig, OtgNetworkConfig};
+use crate::config::{HidConfig, MsdConfig, OtgNetworkConfig, UacConfig};
 use crate::error::Result;
 use crate::otg::OtgNetworkStatus;
 use crate::web::state::UsbApiState;
@@ -16,6 +16,7 @@ pub struct OtgConfigResponse {
    pub hid: HidConfig,
    pub msd: MsdConfig,
    pub network: OtgNetworkConfig,
+    pub uac: UacConfig,
    pub status: OtgNetworkStatus,
 }

@@ -48,6 +49,10 @@ pub(super) async fn update_otg_config_inner(
        if let Some(ref update) = request.network {
            update.apply_to(&mut staged.otg_network);
        }
+        if let Some(ref uac) = request.uac {
+            uac.validate()?;
+            staged.uac = uac.clone();
+        }

        Ok(requested_ch9329_descriptor)
    })
@@ -57,6 +62,7 @@ pub(super) async fn update_otg_config_inner(
        hid: staged_config.hid,
        msd: staged_config.msd,
        network: staged_config.otg_network,
+        uac: staged_config.uac,
        status: state.otg.network_status().await,
    })
 }
--- a/src/web/handlers/config/types.rs
+++ b/src/web/handlers/config/types.rs
@@ -427,6 +427,7 @@ pub struct OtgConfigUpdate {
    pub hid: Option<HidConfigUpdate>,
    pub msd: Option<MsdConfigUpdate>,
    pub network: Option<OtgNetworkConfigUpdate>,
+    pub uac: Option<crate::config::UacConfig>,
 }

 impl HidConfigUpdate {
--- a/src/web/handlers/config/usb_update.rs
+++ b/src/web/handlers/config/usb_update.rs
@@ -47,6 +47,21 @@ where
    let requested_ch9329_descriptor = stage_update(&mut staged_config)?;

    staged_config.enforce_invariants();
+    staged_config.hid.validate_platform()?;
+    staged_config.hid.validate_composite_selection()?;
+    #[cfg(unix)]
+    if staged_config.hid.backend == HidBackend::Ch9329Otg
+        && (old_config.hid.backend != staged_config.hid.backend
+            || old_config.hid.otg_udc != staged_config.hid.otg_udc)
+        && !crate::otg::list_udc_devices()
+            .iter()
+            .any(|udc| Some(udc) == staged_config.hid.otg_udc.as_ref())
+    {
+        return Err(AppError::BadRequest(
+            "Selected USB device controller is missing".into(),
+        ));
+    }
+    super::atx::validate_serial_device_conflict(&staged_config.atx, &staged_config.hid)?;
    staged_config.hid.validate_otg_functions()?;

    #[cfg(unix)]
@@ -179,7 +194,7 @@ where
        }

        let descriptor_was_applied = if let Some(ref descriptor) = requested_ch9329_descriptor {
-            if staged_config.hid.backend == HidBackend::Ch9329 {
+            if staged_config.hid.backend.uses_ch9329() {
                match state.hid.apply_ch9329_descriptor(descriptor).await {
                    Ok(actual) => {
                        staged_config.hid.ch9329_descriptor = actual.descriptor;
@@ -250,7 +265,7 @@ async fn rollback_after_failure(
    {
        rollback_errors.push(format!("runtime rollback failed: {error}"));
    }
-    if restore_descriptor && old_config.hid.backend == HidBackend::Ch9329 {
+    if restore_descriptor && old_config.hid.backend.uses_ch9329() {
        if let Err(error) = state
            .hid
            .apply_ch9329_descriptor(&old_config.hid.ch9329_descriptor)
@@ -276,6 +291,31 @@ mod tests {
    use crate::config::HidBackend;
    use crate::web::handlers::config::types::Ch9329DescriptorConfigUpdate;

+    #[cfg(unix)]
+    #[test]
+    fn composite_advanced_features_can_be_submitted_in_one_usb_transaction() {
+        let request: super::super::types::OtgConfigUpdate = serde_json::from_value(serde_json::json!({
+            "hid": { "backend": "ch9329_otg", "ch9329_port": "/dev/ttyUSB1", "otg_udc": "test.udc" },
+            "msd": { "enabled": true },
+            "network": { "enabled": true },
+            "uac": { "enabled": true, "sample_rate": 48000, "channels": 2 }
+        })).unwrap();
+        let mut config = AppConfig::default();
+        stage_hid_config_update(&mut config.hid, request.hid.as_ref().unwrap()).unwrap();
+        request.msd.as_ref().unwrap().apply_to(&mut config.msd);
+        request
+            .network
+            .as_ref()
+            .unwrap()
+            .apply_to(&mut config.otg_network);
+        config.uac = request.uac.unwrap();
+        config.enforce_invariants();
+        assert!(config.msd.enabled && config.otg_network.enabled && config.uac.enabled);
+        assert!(config.hid.constrained_otg_functions().is_empty());
+        assert_eq!(config.hid.ch9329_port, "/dev/ttyUSB1");
+        assert_eq!(config.hid.otg_udc.as_deref(), Some("test.udc"));
+    }
+
    fn hid_update() -> HidConfigUpdate {
        HidConfigUpdate {
            bluetooth_reset_pairing: None,
--- a/src/web/handlers/hid_api.rs
+++ b/src/web/handlers/hid_api.rs
@@ -11,6 +11,9 @@ pub struct Ch9329DescriptorQuery {
 pub struct HidStatus {
    pub available: bool,
    pub backend: String,
+    pub configured_backend: String,
+    #[cfg(unix)]
+    pub otg: crate::otg::service::OtgRuntimeStatus,
    pub initialized: bool,
    pub online: bool,
    pub supports_absolute_mouse: bool,
@@ -34,9 +37,21 @@ pub async fn hid_otg_self_check(
 /// Get HID status
 pub async fn hid_status(State(state): State<Arc<AppState>>) -> Json<HidStatus> {
    let hid = state.hid.snapshot().await;
+    let config = state.config.get();
    Json(HidStatus {
        available: hid.available,
        backend: hid.backend,
+        configured_backend: config.hid.backend.as_str().to_string(),
+        #[cfg(unix)]
+        otg: state
+            .otg_service
+            .runtime_status(
+                config.hid.backend.uses_otg_hid()
+                    || config.msd.enabled
+                    || config.otg_network.enabled
+                    || config.uac.enabled,
+            )
+            .await,
        initialized: hid.initialized,
        online: hid.online,
        supports_absolute_mouse: hid.supports_absolute_mouse,
--- a/src/web/handlers/setup.rs
+++ b/src/web/handlers/setup.rs
@@ -69,6 +69,8 @@ impl SetupRequest {
        if let Some(enabled) = self.hid_otg_keyboard_leds {
            hid.otg_keyboard_leds = enabled;
        }
+        hid.validate_platform()?;
+        hid.validate_composite_selection()?;
        hid.bluetooth.validate()?;
        hid.validate_otg_functions()?;
        Ok(hid)
@@ -305,6 +307,21 @@ mod tests {
        assert!(hid.effective_otg_keyboard_leds());
    }

+    #[test]
+    #[cfg(target_os = "linux")]
+    fn setup_applies_composite_selection_to_both_usb_paths() {
+        let req = request(json!({
+            "hid_backend": "ch9329_otg", "hid_ch9329_port": "/dev/ttyUSB2",
+            "hid_ch9329_baudrate": 115200, "hid_otg_udc": "test.udc"
+        }));
+        let hid = req.hid_config(&HidConfig::default()).unwrap();
+        assert_eq!(hid.backend, HidBackend::Ch9329Otg);
+        assert_eq!(hid.ch9329_port, "/dev/ttyUSB2");
+        assert_eq!(hid.ch9329_baudrate, 115200);
+        assert_eq!(hid.otg_udc.as_deref(), Some("test.udc"));
+        assert!(hid.constrained_otg_functions().is_empty());
+    }
+
    #[test]
    fn setup_applies_selected_ch9329_port_and_baudrate() {
        let req = request(json!({
--- a/web/src/api/index.ts
+++ b/web/src/api/index.ts
@@ -164,7 +164,7 @@ export const systemApi = {
    video_width?: number
    video_height?: number
    video_fps?: number
-    hid_backend?: 'otg' | 'ch9329' | 'bluetooth' | 'none'
+    hid_backend?: 'otg' | 'ch9329' | 'ch9329_otg' | 'bluetooth' | 'none'
    hid_bluetooth?: { adapter: string; name: string }
    hid_ch9329_port?: string
    hid_ch9329_baudrate?: number
@@ -411,6 +411,8 @@ export const hidApi = {
    request<{
      available: boolean
      backend: string
+      configured_backend: string
+      otg?: import('@/lib/hidGuide').OtgDeviceStatus
      initialized: boolean
      online: boolean
      supports_absolute_mouse: boolean
--- a/web/src/components/ActionBar.vue
+++ b/web/src/components/ActionBar.vue
@@ -58,11 +58,7 @@ const systemStore = useSystemStore()

 const overflowMenuOpen = ref(false)

-const hidBackend = computed(() => (systemStore.hid?.backend ?? '').toLowerCase())
-const isCh9329Backend = computed(() => hidBackend.value.includes('ch9329'))
-const showMsd = computed(() => {
-  return !!systemStore.msd?.available && !isCh9329Backend.value
-})
+const showMsd = computed(() => !!systemStore.msd?.available)
 const props = defineProps<{
  layout?: ConsoleLayout
  mouseMode?: 'absolute' | 'relative'
--- a/web/src/components/HidConfigPopover.vue
+++ b/web/src/components/HidConfigPopover.vue
@@ -17,6 +17,7 @@ import { MousePointer, Move, Loader2 } from 'lucide-vue-next'
 import HelpTooltip from '@/components/HelpTooltip.vue'
 import { useConfigStore } from '@/stores/config'
 import { HidBackend, OtgHidProfile } from '@/types/generated'
+import { usesCh9329 } from '@/lib/hidGuide'

 const props = defineProps<{
  open: boolean
@@ -66,7 +67,7 @@ watch(showCursor, (newValue, oldValue) => {
 const buttonText = computed(() => t('actionbar.hidConfig'))
 const hidSaving = ref(false)
 const hidControlsDisabled = computed(() => hidSaving.value || configStore.hidLoading || !configStore.hid)
-const supportsLinuxCompatibility = computed(() => configStore.hid?.backend === HidBackend.Ch9329)
+const supportsLinuxCompatibility = computed(() => usesCh9329(configStore.hid?.backend))
 const supportsMacosCompatibility = computed(() =>
  supportsLinuxCompatibility.value || configStore.hid?.backend === HidBackend.Otg
 )
--- a/web/src/components/HidDeviceOverview.vue
+++ b/web/src/components/HidDeviceOverview.vue
@@ -3,7 +3,7 @@ import { computed } from 'vue'
 import { useI18n } from 'vue-i18n'
 import type { HidConfig } from '@/types/generated'
 import type { BluetoothStatus } from '@/types/bluetooth'
-import { hidDeviceError, hidDeviceStage, type HidDeviceStatus } from '@/lib/hidGuide'
+import { hidDeviceError, hidDeviceStage, otgDeviceStage, usesCh9329, supportsOtgFunctions, type HidDeviceStatus } from '@/lib/hidGuide'
 const props = defineProps<{ hid: HidConfig | null; status?: HidDeviceStatus | null; bluetooth?: BluetoothStatus | null; error?: string }>()
 const { t } = useI18n()
 const connectionError = computed(() => props.error || hidDeviceError(props.status) || props.bluetooth?.error)
@@ -13,8 +13,8 @@ const stage = computed(() => hidDeviceStage(props.status, props.bluetooth ?? nul
  <div class="space-y-2 text-sm">
    <p class="font-medium">{{ !hid ? t('hidGuide.unconfigured') : hid.backend === 'none' ? t('hidGuide.disabled') : t(`hidGuide.driver_${hid.backend}`) }}</p>
    <dl v-if="hid && hid.backend !== 'none'" class="space-y-1 break-words">
-      <div v-if="hid.backend === 'otg'"><dt class="inline text-muted-foreground">UDC: </dt><dd class="inline">{{ hid.otg_udc || status?.backend === 'otg' && t('hidGuide.legacyAuto') || '—' }}</dd></div>
-      <template v-if="hid.backend === 'ch9329'">
+      <div v-if="supportsOtgFunctions(hid.backend)"><dt class="inline text-muted-foreground">UDC: </dt><dd class="inline">{{ hid.otg_udc || status?.backend === 'otg' && t('hidGuide.legacyAuto') || '—' }}</dd></div>
+      <template v-if="usesCh9329(hid.backend)">
        <div><dt class="inline text-muted-foreground">{{ t('hidGuide.device_ch9329') }}: </dt><dd class="inline">{{ hid.ch9329_port || '—' }}</dd></div>
        <div><dt class="inline text-muted-foreground">{{ t('actionbar.baudrate') }}: </dt><dd class="inline">{{ hid.ch9329_baudrate }}</dd></div>
      </template>
@@ -25,9 +25,13 @@ const stage = computed(() => hidDeviceStage(props.status, props.bluetooth ?? nul
      </template>
    </dl>
    <p v-if="hid && hid.backend !== 'none'" role="status" :class="!connectionError && stage === 'ready' ? 'text-green-600 dark:text-green-400' : 'text-muted-foreground'">
-      {{ t(`hidGuide.${stage}`) }}
+      <span v-if="hid.backend === 'ch9329_otg'">{{ t('hidGuide.keyboardChannel') }}: </span>{{ t(`hidGuide.${stage}`) }}
      <span v-if="bluetooth?.pairing_seconds"> · {{ bluetooth.pairing_seconds }}s</span>
    </p>
+    <template v-if="hid?.backend === 'ch9329_otg'">
+      <p role="status" class="text-muted-foreground">{{ t('hidGuide.otgChannel') }}: {{ t(`hidGuide.${otgDeviceStage(status?.otg)}`) }}</p>
+      <p v-if="status?.otg?.error" role="alert" class="text-destructive break-words">{{ status.otg.error }}</p>
+    </template>
    <p v-if="connectionError" role="alert" class="text-destructive break-words">{{ connectionError }}</p>
  </div>
 </template>
--- a/web/src/components/HidDriverDialog.vue
+++ b/web/src/components/HidDriverDialog.vue
@@ -8,7 +8,7 @@ import { useSystemStore } from '@/stores/system'
 import { request } from '@/api/request'
 import type { HidConfig, MsdConfig } from '@/types/generated'
 import { useHidConnection } from '@/composables/useHidConnection'
-import { deviceRequest, matchesSelection, selectionFrom, type HidSelection } from '@/lib/hidGuide'
+import { deviceRequest, matchesSelection, selectionFrom, supportsOtgFunctions, type HidSelection } from '@/lib/hidGuide'
 import HidDriverForm from './HidDriverForm.vue'
 import HidWiringDiagram from './HidWiringDiagram.vue'
 import HidDeviceOverview from './HidDeviceOverview.vue'
@@ -127,7 +127,7 @@ async function load() {
    if (!systemStore.platform) await systemStore.fetchSystemInfo()
    await refreshHid()
    draft.value = selectionFrom(store.hid)
-    if (otgSupported.value && store.hid?.backend === 'otg') {
+    if (otgSupported.value && supportsOtgFunctions(store.hid?.backend)) {
      const [msd, network, audio] = await Promise.all([refreshMsd(), readConfig<{ enabled: boolean }>('/config/otg-network'), readConfig<{ enabled: boolean }>('/config/uac')])
      disabledUsb.value = [msd.enabled ? t('hidGuide.msd') : '', network.enabled ? t('hidGuide.network') : '', audio.enabled ? t('hidGuide.audio') : ''].filter(Boolean)
    }
@@ -162,7 +162,7 @@ onMounted(load)
          </template>
          <p v-if="connectionTimedOut && !ready && draft.backend !== 'bluetooth'" class="text-sm text-warning">{{ t('hidGuide.connectionTimeout') }}</p>
        </template>
-        <p v-if="!applied && store.hid?.backend === 'otg' && draft.backend !== 'otg' && disabledUsb.length" class="text-sm text-warning">{{ t('hidGuide.disableUsb', { functions: disabledUsb.join('、') }) }}</p>
+        <p v-if="!applied && supportsOtgFunctions(store.hid?.backend) && !supportsOtgFunctions(draft.backend) && disabledUsb.length" class="text-sm text-warning">{{ t('hidGuide.disableUsb', { functions: disabledUsb.join('、') }) }}</p>
        <p v-if="!applied && draft.backend === 'bluetooth'" class="text-sm text-warning">{{ t('hidGuide.resetWarning') }}</p>
        <p v-if="error" role="alert" class="text-sm text-destructive break-words">{{ error }}</p>
        <DialogFooter class="gap-2">
--- a/web/src/components/HidDriverForm.vue
+++ b/web/src/components/HidDriverForm.vue
@@ -9,57 +9,82 @@ import { Cable, RefreshCw } from 'lucide-vue-next'
 import { configApi, type PlatformCapabilities } from '@/api'
 import { request } from '@/api/request'
 import type { BluetoothAdapter } from '@/types/bluetooth'
-import { selectDevice, validName, type HidSelection, type Driver } from '@/lib/hidGuide'
+import { selectDevice, validName, usesCh9329, supportsOtgFunctions, type HidSelection, type Driver } from '@/lib/hidGuide'
 import HidWiringDiagram from './HidWiringDiagram.vue'
-const props = defineProps<{ modelValue: HidSelection; platform: PlatformCapabilities | null; locked?: boolean }>()
+const props = withDefaults(defineProps<{ modelValue: HidSelection; platform: PlatformCapabilities | null; locked?: boolean; deviceOnly?: boolean; idPrefix?: string }>(), { idPrefix: 'hid' })
 const emit = defineEmits<{ 'update:modelValue': [HidSelection]; valid: [boolean] }>()
 const { t } = useI18n()
 const EMPTY_SELECT_VALUE = '__one-kvm-empty-select-value__'
-const options = ref<Array<{ value: string; label: string }>>([])
-const loading = ref(false), error = ref(''), missing = ref('')
+type DeviceField = 'serial' | 'udc' | 'bluetooth'
+type DeviceOption = { value: string; label: string }
+const options = ref<Record<DeviceField, DeviceOption[]>>({ serial: [], udc: [], bluetooth: [] })
+const loading = ref(false), error = ref('')
 let generation = 0
-const drivers = computed(() => (['otg', 'ch9329', 'bluetooth', 'none'] as Driver[])
+const drivers = computed(() => (['otg', 'ch9329', 'ch9329_otg', 'bluetooth', 'none'] as Driver[])
  .filter(driver => props.platform?.hid.backends.includes(driver)))
-const selected = computed(() => props.modelValue.backend === 'otg' ? props.modelValue.otg_udc : props.modelValue.backend === 'ch9329' ? props.modelValue.ch9329_port : props.modelValue.bluetooth.adapter)
-function device(value: string) {
+const fields = computed<DeviceField[]>(() => {
+  if (props.modelValue.backend === 'bluetooth') return ['bluetooth']
+  const result: DeviceField[] = []
+  if (usesCh9329(props.modelValue.backend)) result.push('serial')
+  if (supportsOtgFunctions(props.modelValue.backend)) result.push('udc')
+  return result
+})
+function selected(field: DeviceField): string {
+  return field === 'serial' ? props.modelValue.ch9329_port : field === 'udc' ? props.modelValue.otg_udc : props.modelValue.bluetooth.adapter
+}
+function deviceLabel(field: DeviceField): string {
+  return options.value[field].find(option => option.value === selected(field))?.label
+    || selected(field) || t('hidGuide.selectDevice')
+}
+function assign(draft: HidSelection, field: DeviceField, value: string) {
+  if (field === 'serial') draft.ch9329_port = value
+  if (field === 'udc') draft.otg_udc = value
+  if (field === 'bluetooth') draft.bluetooth.adapter = value
+}
+function device(field: DeviceField, value: string) {
+  if (value === selected(field)) return
  const draft = { ...props.modelValue, bluetooth: { ...props.modelValue.bluetooth } }
-  if (draft.backend === 'otg') draft.otg_udc = value
-  if (draft.backend === 'ch9329') draft.ch9329_port = value
-  if (draft.backend === 'bluetooth') draft.bluetooth.adapter = value
+  assign(draft, field, value)
  emit('update:modelValue', draft)
 }
+function fieldLabel(field: DeviceField): string {
+  return field === 'udc' && props.deviceOnly ? t('hidPage.udcLabel') : t(`hidGuide.device_${field === 'serial' ? 'ch9329' : field === 'udc' ? 'otg' : 'bluetooth'}`)
+}
 async function refresh() {
  const own = ++generation
-  options.value = []; error.value = ''; missing.value = ''; loading.value = true
+  options.value = { serial: [], udc: [], bluetooth: [] }; error.value = ''; loading.value = true
  try {
    if (!drivers.value.includes(props.modelValue.backend) || props.modelValue.backend === 'none') return
-    let next: typeof options.value
+    const next: Record<DeviceField, DeviceOption[]> = { serial: [], udc: [], bluetooth: [] }
    if (props.modelValue.backend === 'bluetooth') {
-      next = (await request<BluetoothAdapter[]>('/hid/bluetooth/adapters')).map(a => ({ value: a.name, label: `${a.name} · ${a.address}` }))
+      next.bluetooth = (await request<BluetoothAdapter[]>('/hid/bluetooth/adapters')).map(a => ({ value: a.name, label: `${a.name} · ${a.address}` }))
    } else {
      const devices = await configApi.listDevices()
-      next = props.modelValue.backend === 'otg' ? devices.udc.map(d => ({ value: d.name, label: d.name })) : devices.serial.map(d => ({ value: d.path, label: `${d.name} · ${d.path}` }))
+      next.udc = devices.udc.map(d => ({ value: d.name, label: d.name }))
+      next.serial = devices.serial.map(d => ({ value: d.path, label: `${d.name} · ${d.path}` }))
    }
    if (own !== generation) return
    options.value = next
-    if (selected.value && !next.some(d => d.value === selected.value)) missing.value = t('hidGuide.missingDevice', { device: selected.value })
-    device(selectDevice(selected.value, next.map(d => d.value)))
-    if (!next.length) error.value = t('hidGuide.noDevices')
+    const draft = { ...props.modelValue, bluetooth: { ...props.modelValue.bluetooth } }
+    for (const field of fields.value) assign(draft, field, selectDevice(selected(field), next[field].map(d => d.value)))
+    if (JSON.stringify(draft) !== JSON.stringify(props.modelValue)) emit('update:modelValue', draft)
  } catch (e) { if (own === generation) error.value = e instanceof Error ? e.message : String(e) }
  finally { if (own === generation) loading.value = false }
 }
-const valid = computed(() => drivers.value.includes(props.modelValue.backend) && (props.modelValue.backend === 'none' || (!loading.value && !error.value && options.value.some(d => d.value === selected.value)
+const valid = computed(() => drivers.value.includes(props.modelValue.backend) && (props.modelValue.backend === 'none' || (!loading.value && !error.value
+  && fields.value.every(field => options.value[field].some(d => d.value === selected(field)))
  && (props.modelValue.backend !== 'bluetooth' || validName(props.modelValue.bluetooth.name))
-  && (props.modelValue.backend !== 'ch9329' || [9600, 19200, 38400, 57600, 115200].includes(props.modelValue.ch9329_baudrate)))))
+  && (!usesCh9329(props.modelValue.backend) || [9600, 19200, 38400, 57600, 115200].includes(props.modelValue.ch9329_baudrate)))))
 watch(valid, value => emit('valid', value), { immediate: true })
-watch(() => [props.modelValue.backend, drivers.value.includes(props.modelValue.backend)], refresh, { immediate: true })
+watch([() => props.modelValue.backend, () => drivers.value.includes(props.modelValue.backend)], refresh, { immediate: true })
 onUnmounted(() => generation++)
+defineExpose({ refresh, loading })
 </script>
 <template>
-  <fieldset :disabled="locked" class="space-y-4 min-w-0">
-    <div class="space-y-1 text-sm">
+  <fieldset :disabled="loading || locked" class="space-y-4 min-w-0">
+    <div v-if="!deviceOnly" class="space-y-1 text-sm">
      <div class="flex min-h-8 items-center justify-between gap-2">
-        <label for="hid-driver">{{ t('hidGuide.driver') }}</label>
+        <label :for="`${idPrefix}-driver`">{{ t('hidGuide.driver') }}</label>
        <div class="flex items-center gap-1">
          <HoverCard v-if="modelValue.backend !== 'none'" :open-delay="150" :close-delay="100">
            <HoverCardTrigger as-child>
@@ -77,7 +102,7 @@ onUnmounted(() => generation++)
            type="button"
            variant="ghost"
            size="icon-sm"
-            :disabled="loading"
+            :disabled="loading || locked"
            :aria-label="t('hidGuide.refreshDevices')"
            :title="t('hidGuide.refreshDevices')"
            @click="refresh"
@@ -88,9 +113,10 @@ onUnmounted(() => generation++)
      </div>
      <Select
        :model-value="modelValue.backend"
+        :disabled="loading || locked"
        @update:model-value="value => emit('update:modelValue', { ...modelValue, backend: String(value) as Driver })"
      >
-        <SelectTrigger id="hid-driver" class="w-full">
+        <SelectTrigger :id="`${idPrefix}-driver`" class="w-full">
          <SelectValue />
        </SelectTrigger>
        <SelectContent>
@@ -101,46 +127,48 @@ onUnmounted(() => generation++)
      </Select>
    </div>
    <p v-if="modelValue.backend === 'none'" class="text-sm text-muted-foreground">{{ t('hidGuide.disabledHelp') }}</p>
-    <label v-if="modelValue.backend !== 'none'" class="block space-y-1 text-sm">
-      <span>{{ t(`hidGuide.device_${modelValue.backend}`) }}</span>
-      <Select
-        :model-value="selected || EMPTY_SELECT_VALUE"
-        :disabled="loading"
-        @update:model-value="value => device(value === EMPTY_SELECT_VALUE ? '' : String(value))"
-      >
-        <SelectTrigger class="w-full">
-          <SelectValue :placeholder="t('hidGuide.selectDevice')" />
-        </SelectTrigger>
-        <SelectContent>
-          <SelectItem :value="EMPTY_SELECT_VALUE" disabled>{{ t('hidGuide.selectDevice') }}</SelectItem>
-          <SelectItem v-for="option in options" :key="option.value" :value="option.value">
-            {{ option.label }}
-          </SelectItem>
-        </SelectContent>
-      </Select>
-    </label>
-    <label v-if="modelValue.backend === 'ch9329'" class="block space-y-1 text-sm">
-      <span>{{ t('actionbar.baudrate') }}</span>
-      <Select
-        :model-value="String(modelValue.ch9329_baudrate)"
-        @update:model-value="value => emit('update:modelValue', { ...modelValue, ch9329_baudrate: Number(value) })"
-      >
-        <SelectTrigger class="w-full">
-          <SelectValue />
-        </SelectTrigger>
-        <SelectContent>
-          <SelectItem v-for="rate in [9600, 19200, 38400, 57600, 115200]" :key="rate" :value="String(rate)">
-            {{ rate }}
-          </SelectItem>
-        </SelectContent>
-      </Select>
-    </label>
-    <label v-if="modelValue.backend === 'bluetooth'" class="block space-y-1 text-sm">
+    <p v-if="!deviceOnly && modelValue.backend === 'ch9329_otg'" class="text-sm text-muted-foreground">{{ t('hidGuide.compositeHelp') }}</p>
+    <div v-for="field in fields" :key="field" class="grid min-w-0 gap-4"
+      :class="{ 'grid-cols-[minmax(0,1fr)_7rem]': field === 'serial' }">
+      <div class="min-w-0 space-y-1 text-sm">
+        <label :for="`${idPrefix}-device-${field}`">{{ fieldLabel(field) }}</label>
+        <Select :model-value="selected(field) || EMPTY_SELECT_VALUE" :disabled="loading || locked"
+          @update:model-value="value => device(field, value === EMPTY_SELECT_VALUE ? '' : String(value))">
+          <SelectTrigger :id="`${idPrefix}-device-${field}`" class="w-full">
+            <SelectValue :placeholder="t('hidGuide.selectDevice')">{{ deviceLabel(field) }}</SelectValue>
+          </SelectTrigger>
+          <SelectContent>
+            <SelectItem :value="EMPTY_SELECT_VALUE" disabled>{{ t('hidGuide.selectDevice') }}</SelectItem>
+            <SelectItem v-if="selected(field) && !options[field].some(d => d.value === selected(field))" :value="selected(field)" disabled>{{ selected(field) }}</SelectItem>
+            <SelectItem v-for="option in options[field]" :key="option.value" :value="option.value">{{ option.label }}</SelectItem>
+          </SelectContent>
+        </Select>
+        <p v-if="!loading && selected(field) && !options[field].some(d => d.value === selected(field))" class="text-warning">{{ t('hidGuide.missingDevice', { device: selected(field) }) }}</p>
+        <p v-if="!loading && !options[field].length" class="text-destructive">{{ fieldLabel(field) }}: {{ t('hidGuide.noDevices') }}</p>
+      </div>
+      <div v-if="field === 'serial'" class="min-w-0 space-y-1 text-sm">
+        <label :for="`${idPrefix}-baudrate`">{{ t('actionbar.baudrate') }}</label>
+        <Select
+          :model-value="String(modelValue.ch9329_baudrate)"
+          :disabled="loading || locked"
+          @update:model-value="value => emit('update:modelValue', { ...modelValue, ch9329_baudrate: Number(value) })"
+        >
+          <SelectTrigger :id="`${idPrefix}-baudrate`" class="w-full">
+            <SelectValue />
+          </SelectTrigger>
+          <SelectContent>
+            <SelectItem v-for="rate in [9600, 19200, 38400, 57600, 115200]" :key="rate" :value="String(rate)">
+              {{ rate }}
+            </SelectItem>
+          </SelectContent>
+        </Select>
+      </div>
+    </div>
+    <label v-if="modelValue.backend === 'bluetooth'" :for="`${idPrefix}-bluetooth-name`" class="block space-y-1 text-sm">
      <span>{{ t('bluetoothHid.name') }}</span>
-      <Input :model-value="modelValue.bluetooth.name" @update:model-value="emit('update:modelValue', { ...modelValue, bluetooth: { ...modelValue.bluetooth, name: String($event) } })" />
+      <Input :id="`${idPrefix}-bluetooth-name`" :disabled="loading || locked" :model-value="modelValue.bluetooth.name" @update:model-value="emit('update:modelValue', { ...modelValue, bluetooth: { ...modelValue.bluetooth, name: String($event) } })" />
      <span v-if="!validName(modelValue.bluetooth.name)" class="text-destructive text-xs">{{ t('hidGuide.nameInvalid') }}</span>
    </label>
-    <p v-if="missing" class="text-sm text-warning">{{ missing }}</p>
    <p v-if="error" role="alert" class="text-sm text-destructive break-words">{{ error }}</p>
  </fieldset>
 </template>
--- a/web/src/components/HidWiringDiagram.vue
+++ b/web/src/components/HidWiringDiagram.vue
@@ -8,7 +8,27 @@ const { t } = useI18n()
 </script>
 <template>
  <figure v-if="backend !== 'none'" class="wiring-diagram rounded-lg border border-border/60 bg-muted/20 p-3 space-y-2">
-    <svg viewBox="0 0 460 184" class="block w-full text-foreground" role="img" :aria-label="t(`hidGuide.wiring_${backend}`)">
+    <svg v-if="backend === 'ch9329_otg'" viewBox="0 0 480 190" class="block w-full text-foreground" role="img" :aria-label="t('hidGuide.wiring_ch9329_otg')">
+      <g fill="none" stroke="currentColor" stroke-width="1.2">
+        <rect x="8" y="51" width="112" height="100" rx="8" />
+        <rect x="174" y="24" width="112" height="35" rx="6" />
+        <rect x="332" y="19" width="140" height="151" rx="8" />
+      </g>
+      <g fill="currentColor" text-anchor="middle" font-size="12">
+        <text x="64" y="80">One-KVM</text>
+        <text x="230" y="46">CH9329</text>
+        <text x="402" y="43">{{ t('hidGuide.kvmSwitch') }}</text>
+        <text x="402" y="84">{{ t('hidGuide.dedicatedHidPort') }}</text>
+        <text x="402" y="143">{{ t('hidGuide.generalUsbPort') }}</text>
+        <text x="146" y="33">UART</text>
+        <text x="229" y="127">OTG USB</text>
+      </g>
+      <g class="connection" fill="none" stroke="currentColor" stroke-linejoin="round">
+        <path d="M120 90h22V42h32m112 0h20v35h26m-8-5 8 5-8 5" />
+        <path d="M120 136h212m-8-5 8 5-8 5" />
+      </g>
+    </svg>
+    <svg v-else viewBox="0 0 460 184" class="block w-full text-foreground" role="img" :aria-label="t(`hidGuide.wiring_${backend}`)">
      <!-- A faint ground plane anchors the perspective without shadows or filters. -->
      <g fill="none" stroke="currentColor" stroke-width=".65" opacity=".07" aria-hidden="true">
        <path d="m7 87 101-46 75 38-101 46Zm270-5 98-45 79 39-98 46M31 99l101-46m-77 58 101-46M302 94l98-45m-71 58 98-45" />
--- a/web/src/composables/useHidConnection.ts
+++ b/web/src/composables/useHidConnection.ts
@@ -1,5 +1,6 @@
 import { ref, watch, onMounted, onUnmounted, onDeactivated, onActivated, type Ref } from 'vue'
 import type { hidApi } from '@/api'
+import { runtimeBackend } from '@/lib/hidGuide'
 import { request } from '@/api/request'
 import type { BluetoothStatus } from '@/types/bluetooth'
 export function useHidConnection(active: Ref<boolean>, backend: Ref<string | undefined>) {
@@ -26,8 +27,8 @@ export function useHidConnection(active: Ref<boolean>, backend: Ref<string | und
      if (hidResult.status === 'rejected') throw hidResult.reason
      if (btResult.status === 'rejected') throw btResult.reason
      const hid = hidResult.value, bt = btResult.value
-      status.value = hid.backend === backend.value ? hid : null
-      bluetooth.value = hid.backend === backend.value ? bt : null
+      status.value = hid.backend === runtimeBackend(backend.value) ? hid : null
+      bluetooth.value = hid.backend === runtimeBackend(backend.value) ? bt : null
      error.value = ''
    } catch (e) {
      if (own !== generation) return
--- a/web/src/i18n/en-US.ts
+++ b/web/src/i18n/en-US.ts
@@ -1,5 +1,17 @@
 export default {
  hidGuide: {
+    driver_ch9329_otg: 'CH9329 + OTG composite mode',
+    compositeHelp: 'CH9329 handles keyboard and mouse. OTG provides virtual media, USB networking and USB audio. Enable advanced functions in their settings.',
+    wiring_ch9329_otg: 'Connect CH9329 to the dedicated keyboard/mouse port and OTG to a general USB port. Use an operation that switches video, keyboard/mouse and USB together.',
+    keyboardChannel: 'CH9329 input',
+    otgChannel: 'OTG functions',
+    kvmSwitch: 'KVM switch',
+    dedicatedHidPort: 'Keyboard/mouse port',
+    generalUsbPort: 'General USB port',
+    advancedFunctions: 'OTG advanced USB functions',
+    otgInactive: 'Not enabled',
+    otgConfigured: 'USB configured by host',
+    otgWaiting: 'Bound, waiting for host',
    missingDevice: 'The previous device {device} is unavailable. Check the current selection.',
    connectionTimeout: 'Connection timed out. Check the data cable and the controlled computer’s USB port. You can connect later or reconfigure.',
    "deviceTitle": "Driver and device",
@@ -50,7 +62,7 @@ export default {
    "pairTimeout": "The pairing window ended. You can open it again.",
    "reopenPairing": "Reopen pairing",
    "resetWarning": "Previous One-KVM HID bonds will be cleared. Remove the old device on the controlled computer before adding it again.",
-    "disableUsb": "Leaving USB OTG will disable: {functions}.",
+    "disableUsb": "Switching drivers will disable: {functions}.",
    "msd": "Virtual disk",
    "network": "USB network",
    "audio": "USB audio",
--- a/web/src/i18n/zh-CN.ts
+++ b/web/src/i18n/zh-CN.ts
@@ -1,5 +1,17 @@
 export default {
  hidGuide: {
+    driver_ch9329_otg: 'CH9329 + OTG 复合模式',
+    compositeHelp: 'CH9329 负责键盘和鼠标，OTG 负责虚拟磁盘、USB 网络和 USB 音频。高级功能需在各自设置中启用。',
+    wiring_ch9329_otg: 'CH9329 接 KVM 专用键鼠口，OTG 接通用 USB 口。请使用同时切换视频、键鼠和通用 USB 的操作。',
+    keyboardChannel: 'CH9329 键鼠',
+    otgChannel: 'OTG 高级功能',
+    kvmSwitch: 'KVM 切换器',
+    dedicatedHidPort: '专用键鼠口',
+    generalUsbPort: '通用 USB 口',
+    advancedFunctions: 'OTG 高级 USB 功能',
+    otgInactive: '未启用',
+    otgConfigured: '主机已配置 USB',
+    otgWaiting: '已绑定，等待主机连接',
    missingDevice: '原设备 {device} 已不可用，请检查当前选择。',
    connectionTimeout: '等待连接超时，请检查数据线及被控机 USB 端口。可稍后连接或重新配置。',
    "deviceTitle": "驱动与设备",
@@ -50,7 +62,7 @@ export default {
    "pairTimeout": "配对窗口已结束，可重新开启。",
    "reopenPairing": "重新开启配对",
    "resetWarning": "将清除原 One-KVM HID 绑定；请在被控机中删除旧设备后重新添加。",
-    "disableUsb": "切出 USB OTG 将关闭：{functions}。",
+    "disableUsb": "切换驱动将关闭：{functions}。",
    "msd": "虚拟磁盘",
    "network": "USB 网络",
    "audio": "USB 音频",
--- a/web/src/lib/hidGuide.ts
+++ b/web/src/lib/hidGuide.ts
@@ -1,6 +1,15 @@
 import type { HidConfig, HidConfigUpdate } from '../types/generated'
 import type { BluetoothStatus } from '../types/bluetooth'
-export type Driver = 'otg' | 'ch9329' | 'bluetooth' | 'none'
+export type Driver = 'otg' | 'ch9329' | 'ch9329_otg' | 'bluetooth' | 'none'
+export function usesCh9329(backend?: string): boolean {
+  return backend === 'ch9329' || backend === 'ch9329_otg'
+}
+export function supportsOtgFunctions(backend?: string): boolean {
+  return backend === 'otg' || backend === 'ch9329_otg'
+}
+export function runtimeBackend(backend?: string): string | undefined {
+  return backend === 'ch9329_otg' ? 'ch9329' : backend
+}
 export interface HidSelection {
  backend: Driver; otg_udc: string; ch9329_port: string; ch9329_baudrate: number
  bluetooth: { adapter: string; name: string }
@@ -11,7 +20,7 @@ export function selectionFrom(hid?: HidConfig | null): HidSelection {
    bluetooth: { adapter: hid?.bluetooth.adapter ?? '', name: hid?.bluetooth.name ?? 'One-KVM HID' } }
 }
 export function selectDevice(saved: string, candidates: string[]): string {
-  return candidates.includes(saved) ? saved : candidates.length === 1 ? candidates[0]! : ''
+  return saved || (candidates.length === 1 ? candidates[0]! : '')
 }
 export function validName(name: string): boolean {
  const length = new TextEncoder().encode(name).length
@@ -21,6 +30,7 @@ export function deviceRequest(draft: HidSelection): HidConfigUpdate {
  const backend = draft.backend as HidConfigUpdate['backend']
  switch (draft.backend) {
    case 'otg': return { backend, otg_udc: draft.otg_udc }
+    case 'ch9329_otg': return { backend, otg_udc: draft.otg_udc, ch9329_port: draft.ch9329_port, ch9329_baudrate: draft.ch9329_baudrate }
    case 'ch9329': return { backend, ch9329_port: draft.ch9329_port, ch9329_baudrate: draft.ch9329_baudrate }
    case 'bluetooth': return { backend, bluetooth: { ...draft.bluetooth }, bluetooth_reset_pairing: true }
    case 'none': return { backend }
@@ -30,6 +40,7 @@ export function matchesSelection(hid: HidConfig, draft: HidSelection): boolean {
  if (hid.backend !== draft.backend) return false
  switch (draft.backend) {
    case 'otg': return hid.otg_udc === draft.otg_udc
+    case 'ch9329_otg': return hid.otg_udc === draft.otg_udc && hid.ch9329_port === draft.ch9329_port && hid.ch9329_baudrate === draft.ch9329_baudrate
    case 'ch9329': return hid.ch9329_port === draft.ch9329_port && hid.ch9329_baudrate === draft.ch9329_baudrate
    case 'bluetooth': return hid.bluetooth.adapter === draft.bluetooth.adapter && hid.bluetooth.name === draft.bluetooth.name
    case 'none': return true
@@ -43,7 +54,25 @@ export function bluetoothStage(status: BluetoothStatus | null): string {
  if (status.pairing_seconds > 0) return 'pairing'
  return status.initialized ? 'waiting' : 'initializing'
 }
+export interface OtgDeviceStatus {
+  enabled: boolean
+  health: 'healthy' | 'applying' | 'degraded'
+  gadget_active: boolean
+  udc: string | null
+  udc_state: string | null
+  error: string | null
+}
+export function otgDeviceStage(status?: OtgDeviceStatus | null): string {
+  if (!status) return 'unknown'
+  if (!status.enabled) return 'otgInactive'
+  if (status.health === 'applying') return 'initializing'
+  if (status.health === 'degraded' || status.error) return 'unknown'
+  if (!status.gadget_active) return 'unknown'
+  return status.udc_state === 'configured' ? 'otgConfigured' : 'otgWaiting'
+}
 export interface HidDeviceStatus {
+  otg?: OtgDeviceStatus | null
+  configured_backend?: string
  backend: string; online: boolean; error?: string | null; error_code?: string | null
 }
 export function hidDeviceError(status?: HidDeviceStatus | null): string | null {
--- a/web/src/types/generated.ts
+++ b/web/src/types/generated.ts
@@ -25,6 +25,7 @@ export interface BluetoothHidConfig {
 export enum HidBackend {
 	Otg = "otg",
 	Ch9329 = "ch9329",
+	Ch9329Otg = "ch9329_otg",
 	Bluetooth = "bluetooth",
 	None = "none",
 }
@@ -548,7 +549,17 @@ export interface OtgNetworkStatus {
 	error?: string;
 }

+export interface OtgRuntimeStatus {
+	enabled: boolean;
+	health: OtgRuntimeHealth;
+	gadget_active: boolean;
+	udc?: string;
+	udc_state?: string;
+	error?: string;
+}
+
 export interface OtgConfigResponse {
+	uac: UacConfig;
 	hid: HidConfig;
 	msd: MsdConfig;
 	network: OtgNetworkConfig;
@@ -564,6 +575,7 @@ export interface OtgNetworkConfigUpdate {
 }

 export interface OtgConfigUpdate {
+	uac?: UacConfig;
 	hid?: HidConfigUpdate;
 	msd?: MsdConfigUpdate;
 	network?: OtgNetworkConfigUpdate;
--- a/web/src/views/ConsoleView.vue
+++ b/web/src/views/ConsoleView.vue
@@ -736,7 +736,7 @@ watch(videoLoading, (loading) => {


 const showMsdStatusCard = computed(() => {
-  return !!(systemStore.msd?.available && systemStore.hid?.backend !== 'ch9329')
+  return !!(systemStore.msd?.available)
 })

 const hidHoverAlign = computed<'start' | 'end'>(() => {
--- a/web/src/views/SettingsView.vue
+++ b/web/src/views/SettingsView.vue
@@ -1,4 +1,5 @@
 <script setup lang="ts">
+import { usesCh9329, supportsOtgFunctions } from '@/lib/hidGuide'
 import McpSettingsCard from '@/components/McpSettingsCard.vue'
 import HidDeviceSettings from '@/components/HidDeviceSettings.vue'
 import ConsoleLayoutPreview from '@/components/ConsoleLayoutPreview.vue'
@@ -1152,7 +1153,7 @@ function clearCh9329DescriptorState() {
 }

 const isCh9329DescriptorSourceCurrent = computed(() => {
-  if (config.value.hid_backend !== 'ch9329') return false
+  if (!usesCh9329(config.value.hid_backend)) return false
  const source = ch9329DescriptorSource.value
  if (!source) return false
  const current = currentCh9329DescriptorSource()
@@ -1160,7 +1161,7 @@ const isCh9329DescriptorSourceCurrent = computed(() => {
 })

 async function loadCh9329Descriptor() {
-  if (config.value.hid_backend !== 'ch9329') return
+  if (!usesCh9329(config.value.hid_backend)) return
  const source = currentCh9329DescriptorSource()
  ch9329DescriptorLoading.value = true
  ch9329DescriptorLoaded.value = false
@@ -1182,14 +1183,14 @@ async function loadCh9329Descriptor() {
 }

 const isCh9329DescriptorValid = computed(() => {
-  if (config.value.hid_backend !== 'ch9329') return true
+  if (!usesCh9329(config.value.hid_backend)) return true
  return utf8ByteLength(ch9329Manufacturer.value) <= 23
    && utf8ByteLength(ch9329Product.value) <= 23
    && utf8ByteLength(ch9329SerialNumber.value) <= 23
 })

 const canEditCh9329Descriptor = computed(() =>
-  config.value.hid_backend === 'ch9329'
+  usesCh9329(config.value.hid_backend)
  && ch9329DescriptorLoaded.value
  && isCh9329DescriptorSourceCurrent.value
  && !ch9329DescriptorLoading.value
@@ -1268,7 +1269,7 @@ const atxDevices = ref<AtxDevices>({
 })

 const ch9329ReservedSerialDevice = computed(() => {
-  if (config.value.hid_backend !== 'ch9329') return ''
+  if (!usesCh9329(config.value.hid_backend)) return ''
  return config.value.hid_serial_device.trim()
 })

@@ -1492,7 +1493,7 @@ async function saveConfig() {
        return
      }
      const hidUpdate: HidConfigUpdate = {}
-      if (config.value.hid_backend === 'ch9329' && isCh9329DescriptorDirty.value) {
+      if (usesCh9329(config.value.hid_backend) && isCh9329DescriptorDirty.value) {
        hidUpdate.ch9329_descriptor = {
          vendor_id: parseInt(ch9329VendorIdHex.value, 16) || 0x1a86,
          product_id: parseInt(ch9329ProductIdHex.value, 16) || 0xe129,
@@ -1501,7 +1502,7 @@ async function saveConfig() {
          serial_number: ch9329SerialNumber.value || '',
        }
      }
-      if (config.value.hid_backend === 'otg') {
+      if (supportsOtgFunctions(config.value.hid_backend)) {
        hidUpdate.otg_descriptor = {
          vendor_id: parseInt(otgVendorIdHex.value, 16) || 0x1d6b,
          product_id: parseInt(otgProductIdHex.value, 16) || 0x0104,
@@ -1509,12 +1510,14 @@ async function saveConfig() {
          product: otgProduct.value || 'One-KVM USB Device',
          serial_number: otgSerialNumber.value || undefined,
        }
-        hidUpdate.otg_profile = 'custom' as OtgHidProfile
-        hidUpdate.otg_functions = { ...config.value.hid_otg_functions }
-        hidUpdate.otg_keyboard_leds = config.value.hid_otg_keyboard_leds
+        if (config.value.hid_backend === 'otg') {
+          hidUpdate.otg_profile = 'custom' as OtgHidProfile
+          hidUpdate.otg_functions = { ...config.value.hid_otg_functions }
+          hidUpdate.otg_keyboard_leds = config.value.hid_otg_keyboard_leds
+        }
      }
-      if (configStore.hid?.backend === 'otg') {
-        const otgEnabled = config.value.hid_backend === 'otg'
+      if (supportsOtgFunctions(configStore.hid?.backend)) {
+        const otgEnabled = supportsOtgFunctions(config.value.hid_backend)
        const response = await configStore.updateOtg({
          hid: hidUpdate,
          msd: {
@@ -1528,15 +1531,14 @@ async function saveConfig() {
            driver_mode: config.value.otg_network_driver as any,
            bridge_interface: config.value.otg_network_interface,
          },
+          uac: {
+            enabled: otgEnabled && config.value.uac_enabled,
+            sample_rate: 48000,
+            channels: 2,
+          },
        })
        otgNetworkStatus.value = response.status
-
-        await uacApi.update({
-          enabled: otgEnabled && config.value.uac_enabled,
-          sample_rate: 48000,
-          channels: 2,
-        })
-      } else if (configStore.hid?.backend === 'ch9329') {
+      } else if (usesCh9329(configStore.hid?.backend)) {
        await configStore.updateHid(hidUpdate)
      }
      await loadConfig()
@@ -1632,11 +1634,11 @@ async function loadConfig() {
      otgSerialNumber.value = hid.otg_descriptor.serial_number || ''
    }
    if (hid.ch9329_descriptor) {
-      if (hid.backend !== 'ch9329') {
+      if (!usesCh9329(hid.backend)) {
        applyCh9329DescriptorForm(hid.ch9329_descriptor, true)
      }
    }
-    if (hid.backend === 'ch9329') {
+    if (usesCh9329(hid.backend)) {
      await loadCh9329Descriptor()
    } else {
      clearCh9329DescriptorState()
@@ -2773,7 +2775,7 @@ watch(updateChannel, async () => {
 watch(() => config.value.hid_backend, () => {
  otgSelfCheckResult.value = null
  otgSelfCheckError.value = ''
-  if (config.value.hid_backend === 'ch9329') {
+  if (usesCh9329(config.value.hid_backend)) {
    void loadCh9329Descriptor()
  } else {
    clearCh9329DescriptorState()
@@ -2783,7 +2785,7 @@ watch(() => config.value.hid_backend, () => {
 watch(
  () => [config.value.hid_serial_device, config.value.hid_serial_baudrate],
  () => {
-    if (config.value.hid_backend === 'ch9329' && !isCh9329DescriptorSourceCurrent.value) {
+    if (usesCh9329(config.value.hid_backend) && !isCh9329DescriptorSourceCurrent.value) {
      clearCh9329DescriptorState()
    }
  },
@@ -3170,10 +3172,10 @@ watch(isWindows, () => {
          <!-- HID Section -->
          <div v-show="activeSection === 'hid'" class="space-y-4">
            <HidDeviceSettings :active="activeSection === 'hid'" :dirty="hidFeaturesDirty" @applied="loadConfig" @discard="loadConfig" />
-            <Card v-if="configStore.hid?.backend === 'otg' || configStore.hid?.backend === 'ch9329'">
+            <Card v-if="supportsOtgFunctions(configStore.hid?.backend) || usesCh9329(configStore.hid?.backend)">
              <CardHeader><CardTitle>{{ t('hidGuide.features') }}</CardTitle></CardHeader>
              <CardContent class="space-y-4">
-                <template v-if="config.hid_backend === 'ch9329'">
+                <template v-if="usesCh9329(config.hid_backend)">
                  <Separator class="my-4" />
                  <div class="space-y-4">
                    <div>
@@ -3261,7 +3263,7 @@ watch(isWindows, () => {
                </template>

                <!-- OTG Descriptor Settings -->
-                <template v-if="config.hid_backend === 'otg'">
+                <template v-if="supportsOtgFunctions(config.hid_backend)">
                  <Separator class="my-4" />
                  <div class="space-y-4">
                    <div>
@@ -3323,10 +3325,10 @@ watch(isWindows, () => {
                  <Separator class="my-4" />
                  <div class="space-y-4">
                    <div>
-                      <h4 class="text-sm font-medium">{{ t('settings.otgHidProfile') }}</h4>
+                      <h4 class="text-sm font-medium">{{ t(config.hid_backend === 'otg' ? 'settings.otgHidProfile' : 'hidGuide.advancedFunctions') }}</h4>
                    </div>
                    <div class="space-y-3">
-                      <div class="grid gap-3 md:grid-cols-2">
+                      <div v-if="config.hid_backend === 'otg'" class="grid gap-3 md:grid-cols-2">
                        <div class="space-y-3 rounded-md border border-border/60 p-3">
                          <div class="flex items-center justify-between gap-4">
                            <div>
@@ -3364,13 +3366,13 @@ watch(isWindows, () => {
                            <Switch v-model="config.hid_otg_functions.mouse_absolute" />
                          </div>
                          <p v-if="hasMacosDragInterfaceConflict" class="text-xs text-warning">{{ t('settings.mouseMacosDragRequiresBoth') }}</p>
-                          <Separator />
-                          <div class="flex items-center justify-between gap-4">
-                            <Label>{{ t('settings.uacMic') }}</Label>
-                            <Switch v-model="config.uac_enabled" />
-                          </div>
+
                        </div>
                      </div>
+                      <div class="flex items-center justify-between gap-4 rounded-md border border-border/60 p-3">
+                        <Label>{{ t('settings.uacMic') }}</Label>
+                        <Switch v-model="config.uac_enabled" />
+                      </div>
                      <div class="space-y-3 rounded-md border border-border/60 p-3">
                        <div class="flex items-center justify-between gap-4">
                          <div>
@@ -3466,7 +3468,7 @@ watch(isWindows, () => {
                        </p>
                      </div>
                    </div>
-                    <p class="text-xs text-warning">
+                    <p v-if="config.hid_backend === 'otg'" class="text-xs text-warning">
                      {{ t('settings.otgProfileWarning') }}
                    </p>
                  </div>
@@ -5419,7 +5421,7 @@ watch(isWindows, () => {
          </div>

          <!-- Save Button (sticky) -->
-          <div v-if="activeSection === 'video' || (activeSection === 'hid' && ['otg', 'ch9329'].includes(configStore.hid?.backend ?? ''))" class="sticky bottom-0 pt-3 sm:pt-4 pb-3 bg-background/95 backdrop-blur supports-[backdrop-filter]:bg-background/80 border-t -mx-3 px-3 sm:-mx-6 sm:px-6 lg:-mx-8 lg:px-8">
+          <div v-if="activeSection === 'video' || (activeSection === 'hid' && (supportsOtgFunctions(configStore.hid?.backend) || usesCh9329(configStore.hid?.backend)))" class="sticky bottom-0 pt-3 sm:pt-4 pb-3 bg-background/95 backdrop-blur supports-[backdrop-filter]:bg-background/80 border-t -mx-3 px-3 sm:-mx-6 sm:px-6 lg:-mx-8 lg:px-8">
            <div class="flex items-center justify-between gap-2 sm:gap-3">
              <p v-if="activeSection === 'hid' && !isHidFunctionSelectionValid" class="flex min-w-0 items-center gap-1.5 text-xs text-warning">
                <AlertTriangle class="size-3.5 shrink-0" />
@@ -5433,7 +5435,7 @@ watch(isWindows, () => {
                <AlertTriangle class="size-3.5 shrink-0" />
                <span class="truncate">{{ t('settings.ch9329StringLengthWarning') }}</span>
              </p>
-              <p v-else-if="activeSection === 'hid' && config.hid_backend === 'ch9329' && ch9329DescriptorLoading" class="flex min-w-0 items-center gap-1.5 text-xs text-warning">
+              <p v-else-if="activeSection === 'hid' && usesCh9329(config.hid_backend) && ch9329DescriptorLoading" class="flex min-w-0 items-center gap-1.5 text-xs text-warning">
                <AlertTriangle class="size-3.5 shrink-0" />
                <span class="truncate">{{ t('settings.ch9329DescriptorLoading') }}</span>
              </p>
--- a/web/src/views/SetupView.vue
+++ b/web/src/views/SetupView.vue
@@ -387,10 +387,11 @@ async function handleSetup() {

  const hid = hidSelection.value
  setupData.hid_backend = hid.backend
-  if (hid.backend === 'ch9329') {
+  if (hid.backend === 'ch9329' || hid.backend === 'ch9329_otg') {
    setupData.hid_ch9329_port = hid.ch9329_port
    setupData.hid_ch9329_baudrate = hid.ch9329_baudrate
-  } else if (hid.backend === 'otg') {
+  }
+  if (hid.backend === 'otg' || hid.backend === 'ch9329_otg') {
    setupData.hid_otg_udc = hid.otg_udc
  } else if (hid.backend === 'bluetooth') {
    setupData.hid_bluetooth = { ...hid.bluetooth }