[PATCH 3/4] usb.h: take advantage of container_of_const()

From: Greg Kroah-Hartman
Date: Thu Dec 01 2022 - 14:32:19 EST


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.

Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
include/linux/usb.h | 44 ++++----------------------------------------
1 file changed, 4 insertions(+), 40 deletions(-)

diff --git a/include/linux/usb.h b/include/linux/usb.h
index 4b463a5e4ba2..cd5637c950ae 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -259,26 +259,8 @@ 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(struct device, __dev, struct usb_interface, dev)

static inline void *usb_get_intfdata(struct usb_interface *intf)
{
@@ -730,26 +712,8 @@ 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(struct device, __dev, struct usb_device, dev)

static inline struct usb_device *__intf_to_usbdev(struct usb_interface *intf)
{
--
2.38.1