static void set_usb_port_removable(struct usb_device *udev)
{
	struct usb_device *hdev = udev->parent;
	struct usb_hub *hub;
	u8 port = udev->portnum;
	u16 wHubCharacteristics;
	bool removable = true;

	if (!hdev)
		return;

	hub = usb_hub_to_struct_hub(udev->parent);

	/*
	 * If the platform firmware has provided information about a port,
	 * use that to determine whether it's removable.
	 */
	switch (hub->ports[udev->portnum - 1]->connect_type) {
	case USB_PORT_CONNECT_TYPE_HOT_PLUG:
		udev->removable = USB_DEVICE_REMOVABLE;
		return;
	case USB_PORT_CONNECT_TYPE_HARD_WIRED:
	case USB_PORT_NOT_USED:
		udev->removable = USB_DEVICE_FIXED;
		return;
	default:
		break;
	}

	/*
	 * Otherwise, check whether the hub knows whether a port is removable
	 * or not
	 */
	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);

	if (!(wHubCharacteristics & HUB_CHAR_COMPOUND))
		return;

	if (hub_is_superspeed(hdev)) {
		if (le16_to_cpu(hub->descriptor->u.ss.DeviceRemovable)
				& (1 << port))
			removable = false;
	} else {
		if (hub->descriptor->u.hs.DeviceRemovable[port / 8] & (1 << (port % 8)))
			removable = false;
	}

	if (removable)
		udev->removable = USB_DEVICE_REMOVABLE;
	else
		udev->removable = USB_DEVICE_FIXED;

}

Unknown