USB: gpio_vbus: add delayed vbus_session calls

Call usb_gadget_vbus_connect() and ...disconnect() from a
workqueue rather than from an irq handler, allowing msleep()
calls in vbus_session.  Update kerneldoc to match.

[ dbrownell@users.sourceforge.net: more kerneldoc updates ]

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 8 insertions, 2 deletions

diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 0460a746480c..bbf45d500b6d 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -598,6 +598,7 @@ static inline int usb_gadget_clear_selfpowered(struct usb_gadget *gadget)
 /**
  * usb_gadget_vbus_connect - Notify controller that VBUS is powered
  * @gadget:The device which now has VBUS power.
+ * Context: can sleep
  *
  * This call is used by a driver for an external transceiver (or GPIO)
  * that detects a VBUS power session starting.  Common responses include
@@ -636,6 +637,7 @@ static inline int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
 /**
  * usb_gadget_vbus_disconnect - notify controller about VBUS session end
  * @gadget:the device whose VBUS supply is being described
+ * Context: can sleep
  *
  * This call is used by a driver for an external transceiver (or GPIO)
  * that detects a VBUS power session ending.  Common responses include
@@ -792,19 +794,20 @@ struct usb_gadget_driver {
 /**
  * usb_gadget_register_driver - register a gadget driver
  * @driver:the driver being registered
+ * Context: can sleep
  *
  * Call this in your gadget driver's module initialization function,
  * to tell the underlying usb controller driver about your driver.
  * The driver's bind() function will be called to bind it to a
  * gadget before this registration call returns.  It's expected that
  * the bind() functions will be in init sections.
- * This function must be called in a context that can sleep.
  */
 int usb_gadget_register_driver(struct usb_gadget_driver *driver);
 
 /**
  * usb_gadget_unregister_driver - unregister a gadget driver
  * @driver:the driver being unregistered
+ * Context: can sleep
  *
  * Call this in your gadget driver's module cleanup function,
  * to tell the underlying usb controller that your driver is
@@ -813,7 +816,6 @@ int usb_gadget_register_driver(struct usb_gadget_driver *driver);
  * to unbind() and clean up any device state, before this procedure
  * finally returns.  It's expected that the unbind() functions
  * will in in exit sections, so may not be linked in some kernels.
- * This function must be called in a context that can sleep.
  */
 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver);
 
diff --git a/include/linux/usb/otg.h b/include/linux/usb/otg.h
index 94df4fe6c6c0..60a52576fd5c 100644
--- a/include/linux/usb/otg.h
+++ b/include/linux/usb/otg.h
@@ -86,6 +86,7 @@ extern int otg_set_transceiver(struct otg_transceiver *);
 extern struct otg_transceiver *otg_get_transceiver(void);
 extern void otg_put_transceiver(struct otg_transceiver *);
 
+/* Context: can sleep */
 static inline int
 otg_start_hnp(struct otg_transceiver *otg)
 {
@@ -102,6 +103,8 @@ otg_set_host(struct otg_transceiver *otg, struct usb_bus *host)
 
 
 /* for usb peripheral controller drivers */
+
+/* Context: can sleep */
 static inline int
 otg_set_peripheral(struct otg_transceiver *otg, struct usb_gadget *periph)
 {
@@ -114,6 +117,7 @@ otg_set_power(struct otg_transceiver *otg, unsigned mA)
         return otg->set_power(otg, mA);
 }
 
+/* Context: can sleep */
 static inline int
 otg_set_suspend(struct otg_transceiver *otg, int suspend)
 {