1 files changed, 15 insertions, 1 deletions

diff --git a/include/linux/usb/composite.h b/include/linux/usb/composite.h
index 882a084a8411..b78cba466d3d 100644
--- a/include/linux/usb/composite.h
+++ b/include/linux/usb/composite.h
@@ -37,6 +37,14 @@
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
 
+/*
+ * USB function drivers should return USB_GADGET_DELAYED_STATUS if they
+ * wish to delay the data/status stages of the control transfer till they
+ * are ready. The control transfer will then be kept from completing till
+ * all the function drivers that requested for USB_GADGET_DELAYED_STAUS
+ * invoke usb_composite_setup_continue().
+ */
+#define USB_GADGET_DELAYED_STATUS       0x7fff  /* Impossibly large value */
 
 struct usb_configuration;
 
@@ -285,6 +293,7 @@ struct usb_composite_driver {
 extern int usb_composite_probe(struct usb_composite_driver *driver,
                                int (*bind)(struct usb_composite_dev *cdev));
 extern void usb_composite_unregister(struct usb_composite_driver *driver);
+extern void usb_composite_setup_continue(struct usb_composite_dev *cdev);
 
 
 /**
@@ -342,7 +351,12 @@ struct usb_composite_dev {
          */
         unsigned                        deactivations;
 
-        /* protects at least deactivation count */
+        /* the composite driver won't complete the control transfer's
+         * data/status stages till delayed_status is zero.
+         */
+        int                             delayed_status;
+
+        /* protects deactivations and delayed_status counts*/
         spinlock_t                      lock;
 };