FIX #51

internal/modem/discovery.go

@@ -14,7 +14,13 @@ import (
 const (
 	djiVendorID    = "2ca3"
 	dji4GProductID = "4006"
+	// quectelVendorID covers Quectel USB modems exposed purely as serial or
+	// RNDIS/ECM devices (for example the EC200A at 2c7c:6005). Their control
+	// interface is not bound to qmi_wwan, so the QMI-binding gate would skip
+	// them even though they expose a usable AT serial port.
+	quectelVendorID = "2c7c"
 )
+
 type SysFSDiscoverer struct {
 	SysRoot string
 	DevRoot string
@@ -83,7 +89,15 @@ func (d *SysFSDiscoverer) Discover(ctx context.Context) ([]Candidate, error) {
 		vendorID := strings.ToLower(readTrimmed(filepath.Join(resolvedDevice, "idVendor")))
 		productID := strings.ToLower(readTrimmed(filepath.Join(resolvedDevice, "idProduct")))
 		if _, bound := qmiBound[deviceName]; !bound && !IsDJI4GUSB(vendorID, productID) {
-			continue
+			// A bound qmi_wwan interface is the strongest vendor-neutral "this is
+			// a live QMI modem" signal, but it excludes Quectel modules running
+			// in a serial or RNDIS/ECM USB composition (no qmi_wwan binding).
+			// Re-admit them by vendor so their AT serial ports stay discoverable;
+			// the candidate is only kept if a ttyUSB/ttyACM node is actually
+			// found below, which is exactly the AT-bearing composition we want.
+			if !isQuectelUSBModem(vendorID) {
+				continue
+			}
 		}
 
 		state := devices[deviceName]
@@ -142,11 +156,19 @@ func (d *SysFSDiscoverer) Discover(ctx context.Context) ([]Candidate, error) {
 		assignQuectelPortRoles(state.candidate.Ports)
 		state.candidate.ATPort = selectATPort(state.candidate.Ports)
 		if !state.candidate.HasATPort() {
-			// A bound QMI interface proves the modem is alive, but the snapshot,
-			// SMS, USSD and eSIM (AT+CSIM) paths all require an AT port. A missing
-			// ttyUSB/ttyACM node almost always means the option/qcserial driver
-			// does not claim the serial interfaces (often a missing PID in its
-			// device-ID table), not that the module lacks an AT interface.
+			// A modem without a usable AT port cannot be driven by vocat, but it
+			// is far more useful to surface it with a discovery issue than to
+			// silently drop it: the operator sees the device is present and gets
+			// told why it is unusable. Two shapes land here:
+			//   * qmi_wwan is bound but no ttyUSB/ttyACM exists — the option/qcserial
+			//     driver did not claim the serial interfaces (often a missing PID
+			//     in its device-ID table, common on Ubuntu for EG25-G carrier
+			//     builds). The modem is alive; it just lacks an AT node.
+			//   * no qmi_wwan binding (Quectel re-admitted by vendor) and no AT
+			//     port — typically an MBIM/RNDIS/ECM composition. The module is on
+			//     the bus but exposes no AT serial interface vocat can open.
+			// Both resolve the same operator action: add the PID to the option
+			// driver or switch the module to a QMI+AT composition.
 			state.candidate.DiscoveryIssue = "at_port_missing"
 		}
 		result = append(result, state.candidate)
@@ -168,6 +190,15 @@ func IsDJI4GUSB(vendorID, productID string) bool {
 		strings.EqualFold(strings.TrimSpace(productID), dji4GProductID)
 }
 
+// isQuectelUSBModem reports whether a USB identity belongs to a Quectel
+// module. Quectel's serial/RNDIS/ECM compositions (e.g. EC200A at 2c7c:6005)
+// do not bind qmi_wwan, so discovery must fall back to the vendor ID to keep
+// them visible. The candidate is only retained if it exposes an AT serial
+// port, which filters out unrelated Quectel-branded peripherals.
+func isQuectelUSBModem(vendorID string) bool {
+	return strings.EqualFold(strings.TrimSpace(vendorID), quectelVendorID)
+}
+
 type discoveredWWANDevice struct {
 	index    string
 	ports    []Port

internal/modem/discovery_test.go

@@ -444,6 +444,115 @@ func TestParseWWANPortName(t *testing.T) {
 	}
 }
 
+func TestSysFSDiscoveryFindsQuectelSerialModemWithoutQMIWWANBinding(t *testing.T) {
+	root := t.TempDir()
+	sysRoot := filepath.Join(root, "sys")
+	devRoot := filepath.Join(root, "dev")
+	usbRoot := filepath.Join(sysRoot, "bus", "usb", "devices")
+	// A Quectel EC200A in its USB-serial composition (2c7c:6005) exposes ttyUSB
+	// control ports but no qmi_wwan-bound interface, so discovery must re-admit
+	// it by vendor instead of skipping it.
+	mustWrite(t, filepath.Join(usbRoot, "1-6", "idVendor"), "2c7c\n")
+	mustWrite(t, filepath.Join(usbRoot, "1-6", "idProduct"), "6005\n")
+	for number, tty := range []string{"ttyUSB0", "ttyUSB1", "ttyUSB2", "ttyUSB3"} {
+		interfaceName := "1-6:1." + strconv.Itoa(number)
+		mustWrite(t, filepath.Join(usbRoot, interfaceName, "bInterfaceNumber"), fmt.Sprintf("%02x\n", number))
+		mustMkdir(t, filepath.Join(usbRoot, interfaceName, tty, "tty", tty))
+	}
+
+	candidates, err := NewSysFSDiscoverer(sysRoot, devRoot).Discover(context.Background())
+	if err != nil {
+		t.Fatalf("Discover: %v", err)
+	}
+	if len(candidates) != 1 {
+		t.Fatalf("got %d candidates, want 1", len(candidates))
+	}
+	candidate := candidates[0]
+	if candidate.VendorID != "2c7c" || candidate.ProductID != "6005" {
+		t.Fatalf("candidate = %#v", candidate)
+	}
+	if candidate.ID != "usb-2c7c-6005-1-6" {
+		t.Fatalf("ID = %q", candidate.ID)
+	}
+	if candidate.ATPort.Name != "ttyUSB2" || candidate.ATPort.Role != PortRoleAT {
+		t.Fatalf("AT port = %#v, want ttyUSB2 at role AT", candidate.ATPort)
+	}
+	if candidate.DiscoveryIssue != "" {
+		t.Fatalf("discovery issue = %q, want none", candidate.DiscoveryIssue)
+	}
+}
+
+func TestSysFSDiscoveryMarksQuectelPeripheralWithoutATPort(t *testing.T) {
+	root := t.TempDir()
+	sysRoot := filepath.Join(root, "sys")
+	devRoot := filepath.Join(root, "dev")
+	usbRoot := filepath.Join(sysRoot, "bus", "usb", "devices")
+	// A Quectel-branded peripheral exposing only a network interface (no
+	// ttyUSB/ttyACM, no qmi_wwan binding) cannot be driven yet, but vocat
+	// surfaces it with at_port_missing instead of silently dropping it so the
+	// operator sees the device is present and learns what to fix.
+	mustWrite(t, filepath.Join(usbRoot, "1-8", "idVendor"), "2c7c\n")
+	mustWrite(t, filepath.Join(usbRoot, "1-8", "idProduct"), "6005\n")
+	mustMkdir(t, filepath.Join(usbRoot, "1-8:1.0", "net", "enx001122334455"))
+
+	candidates, err := NewSysFSDiscoverer(sysRoot, devRoot).Discover(context.Background())
+	if err != nil {
+		t.Fatalf("Discover: %v", err)
+	}
+	if len(candidates) != 1 {
+		t.Fatalf("got %d candidates, want 1", len(candidates))
+	}
+	candidate := candidates[0]
+	if candidate.DiscoveryIssue != "at_port_missing" {
+		t.Fatalf("discovery issue = %q, want at_port_missing", candidate.DiscoveryIssue)
+	}
+	if candidate.HasATPort() {
+		t.Fatalf("candidate unexpectedly has an AT port: %#v", candidate.ATPort)
+	}
+	if candidate.NetworkInterface != "enx001122334455" {
+		t.Fatalf("network interface = %q", candidate.NetworkInterface)
+	}
+}
+
+func TestSysFSDiscoveryMarksQuectelMBIMCompositionWithoutATPort(t *testing.T) {
+	root := t.TempDir()
+	sysRoot := filepath.Join(root, "sys")
+	devRoot := filepath.Join(root, "dev")
+	usbRoot := filepath.Join(sysRoot, "bus", "usb", "devices")
+	// An EG25-G in MBIM composition (2c7c:0900) exposes cdc-wdm + net but no
+	// ttyUSB and has no qmi_wwan binding (cdc_mbim binds the control interface
+	// instead). vocat has no MBIM backend, so it must surface the device with
+	// at_port_missing rather than hiding it.
+	mustWrite(t, filepath.Join(usbRoot, "1-6", "idVendor"), "2c7c\n")
+	mustWrite(t, filepath.Join(usbRoot, "1-6", "idProduct"), "0900\n")
+	mustWrite(t, filepath.Join(usbRoot, "1-6", "product"), "EG25-G\n")
+	mustMkdir(t, filepath.Join(usbRoot, "1-6:1.0", "usbmisc", "cdc-wdm0"))
+	mustMkdir(t, filepath.Join(usbRoot, "1-6:1.0", "net", "wwp0s20f0u6"))
+
+	candidates, err := NewSysFSDiscoverer(sysRoot, devRoot).Discover(context.Background())
+	if err != nil {
+		t.Fatalf("Discover: %v", err)
+	}
+	if len(candidates) != 1 {
+		t.Fatalf("got %d candidates, want 1", len(candidates))
+	}
+	candidate := candidates[0]
+	if candidate.DiscoveryIssue != "at_port_missing" {
+		t.Fatalf("discovery issue = %q, want at_port_missing", candidate.DiscoveryIssue)
+	}
+	if candidate.HasATPort() {
+		t.Fatalf("candidate unexpectedly has an AT port: %#v", candidate.ATPort)
+	}
+	if candidate.Product != "EG25-G" {
+		t.Fatalf("product = %q", candidate.Product)
+	}
+	// cdc-wdm0 sits under usbmisc/, which scanUSBInterface reports as a QMI
+	// control name; either way the device must appear present, not vanish.
+	if candidate.QMIControl == "" && candidate.NetworkInterface == "" {
+		t.Fatalf("candidate has neither QMI control nor net interface: %#v", candidate)
+	}
+}
+
 func mustWrite(t *testing.T, path, value string) {
 	t.Helper()
 	mustMkdir(t, filepath.Dir(path))

web/src/components/devices/DiscoveredDeviceRow.tsx

@@ -23,7 +23,9 @@ export function DiscoveredDeviceRow({
     ? t("系统已发现 USB 读卡器，但 PC/SC 服务未运行；请安装并启动 pcscd 后重新扫描。")
     : device.discoveryIssue === "pcsc_driver_missing"
       ? t("系统已发现 USB 读卡器，但 PC/SC 驱动未加载；请安装 libccid 或厂商驱动后重新扫描。")
-      : "";
+      : device.discoveryIssue === "at_port_missing"
+        ? t("已发现该模组，但未找到 AT 串口：通常是 option 驱动未认该 PID 或模组处于 MBIM/RNDIS 组态。可 `echo 2c7c <pid> | sudo tee /sys/bus/usb-serial/drivers/option1/new_id` 后重扫，或用 AT+QCFG 切到 QMI+AT 组态。")
+        : "";
   return (
     <button
       type="button"

web/src/pages/DevicesPage.tsx

@@ -381,6 +381,10 @@ export default function DevicesPage() {
       message.warning(t("系统已发现 USB 读卡器，但 PC/SC 驱动未加载；请安装 libccid 或厂商驱动后重新扫描。"));
       return;
     }
+    if (d.discoveryIssue === "at_port_missing") {
+      message.warning(t("已发现该模组，但未找到 AT 串口：通常是 option 驱动未认该 PID 或模组处于 MBIM/RNDIS 组态。可 `echo 2c7c <pid> | sudo tee /sys/bus/usb-serial/drivers/option1/new_id` 后重扫，或用 AT+QCFG 切到 QMI+AT 组态。"));
+      return;
+    }
     if (d.degraded) {
       message.warning(t("无法读取该设备 IMEI（可能控制口挂死），请执行 AT!RESET 或切换组态后重试"));
       return;