diff --git a/src/UsbCameraImpl.cpp b/src/UsbCameraImpl.cpp
index c7ffda67fc..4dc35146f4 100644
--- a/src/UsbCameraImpl.cpp
+++ b/src/UsbCameraImpl.cpp
@@ -107,48 +107,6 @@ int UsbCameraImpl::PercentageToRaw(const UsbCameraProperty& rawProp,
          (rawProp.maximum - rawProp.minimum) * (percentValue / 100.0);
 }
 
-static std::unique_ptr<UsbCameraProperty> ExtCtrlIoctl(int fd, __u32* id) {
-  int rc;
-  std::unique_ptr<UsbCameraProperty> prop;
-#ifdef VIDIOC_QUERY_EXT_CTRL
-  v4l2_query_ext_ctrl qc_ext;
-  std::memset(&qc_ext, 0, sizeof(qc_ext));
-  qc_ext.id = *id;
-  rc = TryIoctl(fd, VIDIOC_QUERY_EXT_CTRL, &qc_ext);
-  if (rc == 0) {
-    *id = qc_ext.id;  // copy back
-    // We don't support array types
-    if (qc_ext.elems > 1 || qc_ext.nr_of_dims > 0) return nullptr;
-    prop = llvm::make_unique<UsbCameraProperty>(qc_ext);
-  }
-#endif
-  if (!prop) {
-    // Fall back to normal QUERYCTRL
-    struct v4l2_queryctrl qc;
-    std::memset(&qc, 0, sizeof(qc));
-    qc.id = *id;
-    rc = TryIoctl(fd, VIDIOC_QUERYCTRL, &qc);
-    *id = qc.id;  // copy back
-    if (rc != 0) return nullptr;
-    prop = llvm::make_unique<UsbCameraProperty>(qc);
-  }
-
-  // Cache enum property choices
-  if (prop->propKind == CS_PROP_ENUM) {
-    prop->enumChoices.resize(prop->maximum + 1);
-    v4l2_querymenu qmenu;
-    std::memset(&qmenu, 0, sizeof(qmenu));
-    qmenu.id = *id;
-    for (int i = prop->minimum; i <= prop->maximum; ++i) {
-      qmenu.index = static_cast<__u32>(i);
-      if (TryIoctl(fd, VIDIOC_QUERYMENU, &qmenu) != 0) continue;
-      prop->enumChoices[i] = reinterpret_cast<const char*>(qmenu.name);
-    }
-  }
-
-  return prop;
-}
-
 static bool GetDescriptionSysV4L(llvm::StringRef path, std::string* desc) {
   llvm::SmallString<64> ifpath{"/sys/class/video4linux/"};
   ifpath += path.substr(5);
@@ -1012,7 +970,7 @@ void UsbCameraImpl::DeviceCacheProperties() {
       ;
   __u32 id = nextFlags;
 
-  while (auto prop = ExtCtrlIoctl(fd, &id)) {
+  while (auto prop = UsbCameraProperty::DeviceQuery(fd, &id)) {
     DeviceCacheProperty(std::move(prop));
     id |= nextFlags;
   }
@@ -1020,12 +978,13 @@ void UsbCameraImpl::DeviceCacheProperties() {
   if (id == nextFlags) {
     // try just enumerating standard...
     for (id = V4L2_CID_BASE; id < V4L2_CID_LASTP1; ++id) {
-      if (auto prop = ExtCtrlIoctl(fd, &id))
+      if (auto prop = UsbCameraProperty::DeviceQuery(fd, &id))
         DeviceCacheProperty(std::move(prop));
     }
     // ... and custom controls
     std::unique_ptr<UsbCameraProperty> prop;
-    for (id = V4L2_CID_PRIVATE_BASE; (prop = ExtCtrlIoctl(fd, &id)); ++id)
+    for (id = V4L2_CID_PRIVATE_BASE;
+         (prop = UsbCameraProperty::DeviceQuery(fd, &id)); ++id)
       DeviceCacheProperty(std::move(prop));
   }
 }
diff --git a/src/UsbCameraProperty.cpp b/src/UsbCameraProperty.cpp
index 848d15fbe4..43456f0e10 100644
--- a/src/UsbCameraProperty.cpp
+++ b/src/UsbCameraProperty.cpp
@@ -8,6 +8,7 @@
 #include "UsbCameraProperty.h"
 
 #include "llvm/SmallString.h"
+#include "llvm/STLExtras.h"
 
 #include "UsbUtil.h"
 
@@ -202,6 +203,49 @@ UsbCameraProperty::UsbCameraProperty(const struct v4l2_queryctrl& ctrl)
       llvm::StringRef(reinterpret_cast<const char*>(ctrl.name), len), name_buf);
 }
 
+std::unique_ptr<UsbCameraProperty> UsbCameraProperty::DeviceQuery(int fd,
+                                                                  __u32* id) {
+  int rc;
+  std::unique_ptr<UsbCameraProperty> prop;
+#ifdef VIDIOC_QUERY_EXT_CTRL
+  v4l2_query_ext_ctrl qc_ext;
+  std::memset(&qc_ext, 0, sizeof(qc_ext));
+  qc_ext.id = *id;
+  rc = TryIoctl(fd, VIDIOC_QUERY_EXT_CTRL, &qc_ext);
+  if (rc == 0) {
+    *id = qc_ext.id;  // copy back
+    // We don't support array types
+    if (qc_ext.elems > 1 || qc_ext.nr_of_dims > 0) return nullptr;
+    prop = llvm::make_unique<UsbCameraProperty>(qc_ext);
+  }
+#endif
+  if (!prop) {
+    // Fall back to normal QUERYCTRL
+    struct v4l2_queryctrl qc;
+    std::memset(&qc, 0, sizeof(qc));
+    qc.id = *id;
+    rc = TryIoctl(fd, VIDIOC_QUERYCTRL, &qc);
+    *id = qc.id;  // copy back
+    if (rc != 0) return nullptr;
+    prop = llvm::make_unique<UsbCameraProperty>(qc);
+  }
+
+  // Cache enum property choices
+  if (prop->propKind == CS_PROP_ENUM) {
+    prop->enumChoices.resize(prop->maximum + 1);
+    v4l2_querymenu qmenu;
+    std::memset(&qmenu, 0, sizeof(qmenu));
+    qmenu.id = *id;
+    for (int i = prop->minimum; i <= prop->maximum; ++i) {
+      qmenu.index = static_cast<__u32>(i);
+      if (TryIoctl(fd, VIDIOC_QUERYMENU, &qmenu) != 0) continue;
+      prop->enumChoices[i] = reinterpret_cast<const char*>(qmenu.name);
+    }
+  }
+
+  return prop;
+}
+
 bool UsbCameraProperty::DeviceGet(std::unique_lock<std::mutex>& lock, int fd) {
   if (fd < 0) return true;
   unsigned idCopy = id;
diff --git a/src/UsbCameraProperty.h b/src/UsbCameraProperty.h
index eae9480495..502f0a65b4 100644
--- a/src/UsbCameraProperty.h
+++ b/src/UsbCameraProperty.h
@@ -8,6 +8,7 @@
 #ifndef CS_USBCAMERAPROPERTY_H_
 #define CS_USBCAMERAPROPERTY_H_
 
+#include <memory>
 #include <mutex>
 
 #ifdef __linux__
@@ -45,6 +46,8 @@ class UsbCameraProperty : public PropertyImpl {
 #endif
   UsbCameraProperty(const struct v4l2_queryctrl& ctrl);
 
+  static std::unique_ptr<UsbCameraProperty> DeviceQuery(int fd, __u32* id);
+
   bool DeviceGet(std::unique_lock<std::mutex>& lock, int fd);
   bool DeviceSet(std::unique_lock<std::mutex>& lock, int fd) const;
   bool DeviceSet(std::unique_lock<std::mutex>& lock, int fd, int newValue,