USB: make devnode() callback in usb_class_driver take a const *

With the changes to the driver core to make more pointers const, the USB
subsystem also needs to be modified to take a const * for the devnode
callback so that the driver core's constant pointer will also be
properly propagated.

Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: Juergen Stuber <starblue@users.sourceforge.net>
Reviewed-by: Johan Hovold <johan@kernel.org>
Acked-by: Pete Zaitcev <zaitcev@redhat.com>
Reviewed-by: Jiri Kosina <jkosina@suse.cz>
Link: https://lore.kernel.org/r/20221001165128.2688526-1-gregkh@linuxfoundation.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/hid/usbhid/hiddev.c

@@ -857,7 +857,7 @@ static const struct file_operations hiddev_fops = {
 	.llseek		= noop_llseek,
 };
 
-static char *hiddev_devnode(struct device *dev, umode_t *mode)
+static char *hiddev_devnode(const struct device *dev, umode_t *mode)
 {
 	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
 }

drivers/usb/class/usblp.c

@@ -1090,7 +1090,7 @@ static const struct file_operations usblp_fops = {
 	.llseek =	noop_llseek,
 };
 
-static char *usblp_devnode(struct device *dev, umode_t *mode)
+static char *usblp_devnode(const struct device *dev, umode_t *mode)
 {
 	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
 }

drivers/usb/misc/iowarrior.c

@@ -717,7 +717,7 @@ static const struct file_operations iowarrior_fops = {
 	.llseek = noop_llseek,
 };
 
-static char *iowarrior_devnode(struct device *dev, umode_t *mode)
+static char *iowarrior_devnode(const struct device *dev, umode_t *mode)
 {
 	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
 }

drivers/usb/misc/legousbtower.c

@@ -245,7 +245,7 @@ static const struct file_operations tower_fops = {
 	.llseek =	tower_llseek,
 };
 
-static char *legousbtower_devnode(struct device *dev, umode_t *mode)
+static char *legousbtower_devnode(const struct device *dev, umode_t *mode)
 {
 	return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
 }

include/linux/usb.h

@@ -1321,7 +1321,7 @@ struct usb_device_driver {
  */
 struct usb_class_driver {
 	char *name;
-	char *(*devnode)(struct device *dev, umode_t *mode);
+	char *(*devnode)(const struct device *dev, umode_t *mode);
 	const struct file_operations *fops;
 	int minor_base;
 };