usb: Use hub port data to determine whether a port is removable
authorMatthew Garrett <mjg@redhat.com>
Fri, 3 Feb 2012 22:11:55 +0000 (17:11 -0500)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 9 Feb 2012 16:40:11 +0000 (08:40 -0800)
Hubs have a flag to indicate whether a given port carries removable devices
or not. This is not strictly accurate in that some built-in devices
will be flagged as removable, but followup patches will make use of platform
data to make this more reliable.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/core/hub.c

index a0613d8..2d773cb 100644 (file)
@@ -1838,6 +1838,37 @@ fail:
        return err;
 }
 
+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 = hdev_to_hub(udev->parent);
+
+       wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
+
+       if (!(wHubCharacteristics & HUB_CHAR_COMPOUND))
+               return;
+
+       if (hub_is_superspeed(hdev)) {
+               if (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;
+}
 
 /**
  * usb_new_device - perform initial device setup (usbcore-internal)
@@ -1896,6 +1927,15 @@ int usb_new_device(struct usb_device *udev)
        announce_device(udev);
 
        device_enable_async_suspend(&udev->dev);
+
+       /*
+        * check whether the hub marks this port as non-removable. Do it
+        * now so that platform-specific data can override it in
+        * device_add()
+        */
+       if (udev->parent)
+               set_usb_port_removable(udev);
+
        /* Register the device.  The device driver is responsible
         * for configuring the device and invoking the add-device
         * notifier chain (used by usbfs and possibly others).