usb: gadget: move bind callback into driver struct usb_composite_driver

It was moved to be an argument in 07a18bd ("usb gadget: don't
save bind callback in struct usb_composite_driver"). The reason was to
avoid the section missmatch. The warning was shown because ->bind is
marked as __init becuase it is a one time init. The warning can be also
suppresed by whitelisting the variable i.e. rename it to lets say _probe.

Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/composite.c

@@ -32,7 +32,6 @@
 #define USB_BUFSIZ	1024
 
 static struct usb_composite_driver *composite;
-static int (*composite_gadget_bind)(struct usb_composite_dev *cdev);
 
 /* Some systems will need runtime overrides for the  product identifiers
  * published in the device descriptor, either numbers or strings or both.
@@ -1468,7 +1467,7 @@ static int composite_bind(struct usb_gadget *gadget)
 	 * serial number), register function drivers, potentially update
 	 * power state and consumption, etc
 	 */
-	status = composite_gadget_bind(cdev);
+	status = composite->bind(cdev);
 	if (status < 0)
 		goto fail;
 
@@ -1621,7 +1620,9 @@ static struct usb_gadget_driver composite_driver = {
 int usb_composite_probe(struct usb_composite_driver *driver,
 			       int (*bind)(struct usb_composite_dev *cdev))
 {
-	if (!driver || !driver->dev || !bind || composite)
+	if (!driver || !driver->dev || composite)
+		return -EINVAL;
+	if (!bind && !driver->bind)
 		return -EINVAL;
 
 	if (!driver->name)
@@ -1632,7 +1633,8 @@ int usb_composite_probe(struct usb_composite_driver *driver,
 	composite_driver.driver.name = driver->name;
 	composite_driver.max_speed = driver->max_speed;
 	composite = driver;
-	composite_gadget_bind = bind;
+	if (!driver->bind)
+		driver->bind = bind;
 
 	return usb_gadget_probe_driver(&composite_driver, composite_bind);
 }

include/linux/usb/composite.h

@@ -257,12 +257,16 @@ void usb_remove_config(struct usb_composite_dev *,
  *	not set.
  * @dev: Template descriptor for the device, including default device
  *	identifiers.
- * @strings: tables of strings, keyed by identifiers assigned during bind()
+ * @strings: tables of strings, keyed by identifiers assigned during @bind
  *	and language IDs provided in control requests
  * @max_speed: Highest speed the driver supports.
  * @needs_serial: set to 1 if the gadget needs userspace to provide
  * 	a serial number.  If one is not provided, warning will be printed.
- * @unbind: Reverses bind; called as a side effect of unregistering
+ * @bind: (REQUIRED) Used to allocate resources that are shared across the
+ *	whole device, such as string IDs, and add its configurations using
+ *	@usb_add_config(). This may fail by returning a negative errno
+ *	value; it should return zero on successful initialization.
+ * @unbind: Reverses @bind; called as a side effect of unregistering
  *	this driver.
  * @disconnect: optional driver disconnect method
  * @suspend: Notifies when the host stops sending USB traffic,
@@ -271,9 +275,9 @@ void usb_remove_config(struct usb_composite_dev *,
  *	before function notifications
  *
  * Devices default to reporting self powered operation.  Devices which rely
- * on bus powered operation should report this in their @bind() method.
+ * on bus powered operation should report this in their @bind method.
  *
- * Before returning from bind, various fields in the template descriptor
+ * Before returning from @bind, various fields in the template descriptor
  * may be overridden.  These include the idVendor/idProduct/bcdDevice values
  * normally to bind the appropriate host side driver, and the three strings
  * (iManufacturer, iProduct, iSerialNumber) normally used to provide user
@@ -291,6 +295,7 @@ struct usb_composite_driver {
 	enum usb_device_speed			max_speed;
 	unsigned		needs_serial:1;
 
+	int			(*bind)(struct usb_composite_dev *cdev);
 	int			(*unbind)(struct usb_composite_dev *);
 
 	void			(*disconnect)(struct usb_composite_dev *);