USB: gadget: composite device-level suspend/resume hooks

Address one open question in the composite gadget framework:
Yes, we should have device-level suspend/resume callbacks
in addition to the function-level ones.  We have at least one
scenario (with gadget zero in OTG test mode) that's awkward
to handle without it.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 40f1da7..59e8523 100644 (file)
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -1014,7 +1014,7 @@ composite_suspend(struct usb_gadget *gadget)
        struct usb_composite_dev        *cdev = get_gadget_data(gadget);
        struct usb_function             *f;
 
-       /* REVISIT:  should we have config and device level
+       /* REVISIT:  should we have config level
         * suspend/resume callbacks?
         */
        DBG(cdev, "suspend\n");
@@ -1024,6 +1024,8 @@ composite_suspend(struct usb_gadget *gadget)
                                f->suspend(f);
                }
        }
+       if (composite->suspend)
+               composite->suspend(cdev);
 }
 
 static void
@@ -1032,10 +1034,12 @@ composite_resume(struct usb_gadget *gadget)
        struct usb_composite_dev        *cdev = get_gadget_data(gadget);
        struct usb_function             *f;
 
-       /* REVISIT:  should we have config and device level
+       /* REVISIT:  should we have config level
         * suspend/resume callbacks?
         */
        DBG(cdev, "resume\n");
+       if (composite->resume)
+               composite->resume(cdev);
        if (cdev->config) {
                list_for_each_entry(f, &cdev->config->functions, list) {
                        if (f->resume)

diff --git a/include/linux/usb/composite.h b/include/linux/usb/composite.h
index 935c380..acd7b0f 100644 (file)
--- a/include/linux/usb/composite.h
+++ b/include/linux/usb/composite.h
@@ -244,6 +244,10 @@ int usb_add_config(struct usb_composite_dev *,
  *     value; it should return zero on successful initialization.
  * @unbind: Reverses @bind(); called as a side effect of unregistering
  *     this driver.
+ * @suspend: Notifies when the host stops sending USB traffic,
+ *     after function notifications
+ * @resume: Notifies configuration when the host restarts USB traffic,
+ *     before function notifications
  *
  * Devices default to reporting self powered operation.  Devices which rely
  * on bus powered operation should report this in their @bind() method.
@@ -268,6 +272,10 @@ struct usb_composite_driver {
 
        int                     (*bind)(struct usb_composite_dev *);
        int                     (*unbind)(struct usb_composite_dev *);
+
+       /* global suspend hooks */
+       void                    (*suspend)(struct usb_composite_dev *);
+       void                    (*resume)(struct usb_composite_dev *);
 };
 
 extern int usb_composite_register(struct usb_composite_driver *);