USB: skip Set-Interface(0) if already in altsetting 0

[h-e-n] / drivers / usb / core / driver.c

diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index 3d7793d..8c08130 100644 (file)
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -279,7 +279,9 @@ static int usb_unbind_interface(struct device *dev)
         * altsetting means creating new endpoint device entries).
         * When either of these happens, defer the Set-Interface.
         */
-       if (!error && intf->dev.power.status == DPM_ON)
+       if (intf->cur_altsetting->desc.bAlternateSetting == 0)
+               ;       /* Already in altsetting 0 so skip Set-Interface */
+       else if (!error && intf->dev.power.status == DPM_ON)
                usb_set_interface(udev, intf->altsetting[0].
                                desc.bInterfaceNumber, 0);
        else