usb.h: take advantage of container_of_const()

Instead of rolling our own const-checking logic in to_usb_interface()
and to_usb_device() use the newly added container_of_const() instead,
making the logic much simpler overall.

Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20221205121206.166576-3-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/linux/usb.h b/include/linux/usb.h
index 4b463a5..010c681 100644 (file)
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -259,26 +259,7 @@ struct usb_interface {
        struct work_struct reset_ws;    /* for resets in atomic context */
 };
 
-static inline struct usb_interface *__to_usb_interface(struct device *d)
-{
-       return container_of(d, struct usb_interface, dev);
-}
-
-static inline const struct usb_interface *__to_usb_interface_const(const struct device *d)
-{
-       return container_of(d, struct usb_interface, dev);
-}
-
-/*
- * container_of() will happily take a const * and spit back a non-const * as it
- * is just doing pointer math.  But we want to be a bit more careful in the USB
- * driver code, so manually force any const * of a device to also be a const *
- * to a usb_device.
- */
-#define to_usb_interface(dev)                                          \
-       _Generic((dev),                                                 \
-                const struct device *: __to_usb_interface_const,       \
-                struct device *: __to_usb_interface)(dev)
+#define to_usb_interface(__dev)        container_of_const(__dev, struct usb_interface, dev)
 
 static inline void *usb_get_intfdata(struct usb_interface *intf)
 {
@@ -730,26 +711,7 @@ struct usb_device {
        unsigned use_generic_driver:1;
 };
 
-static inline struct usb_device *__to_usb_device(struct device *d)
-{
-       return container_of(d, struct usb_device, dev);
-}
-
-static inline const struct usb_device *__to_usb_device_const(const struct device *d)
-{
-       return container_of(d, struct usb_device, dev);
-}
-
-/*
- * container_of() will happily take a const * and spit back a non-const * as it
- * is just doing pointer math.  But we want to be a bit more careful in the USB
- * driver code, so manually force any const * of a device to also be a const *
- * to a usb_device.
- */
-#define to_usb_device(dev)                                     \
-       _Generic((dev),                                         \
-                const struct device *: __to_usb_device_const,  \
-                struct device *: __to_usb_device)(dev)
+#define to_usb_device(__dev)   container_of_const(__dev, struct usb_device, dev)
 
 static inline struct usb_device *__intf_to_usbdev(struct usb_interface *intf)
 {