USB: Add a new quirk: USB_QUIRK_HONOR_BNUMINTERFACES
Add a new quirk USB_QUIRK_HONOR_BNUMINTERFACES, when this quirk is
set and a device has more interface descriptors in a configuration
then it claims to have in config->bNumInterfaces, ignore all additional
interfaces.
This is needed for devices which try to hide unused interfaces by only
lowering config->bNumInterfaces, and which can't handle if you try to talk
to the "hidden" interfaces.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/include/linux/usb/quirks.h b/include/linux/usb/quirks.h
index 0a555dd..16b7f33 100644
--- a/include/linux/usb/quirks.h
+++ b/include/linux/usb/quirks.h
@@ -22,4 +22,8 @@
/*device will morph if reset, don't use reset for handling errors */
#define USB_QUIRK_RESET_MORPHS 0x00000010
+/* device has more interface descriptions than the bNumInterfaces count,
+ and can't handle talking to these interfaces */
+#define USB_QUIRK_HONOR_BNUMINTERFACES 0x00000020
+
#endif /* __LINUX_USB_QUIRKS_H */