debugfs: remove return value of debugfs_create_u32()

No one checks the return value of debugfs_create_u32(), as it's not
needed, so make the return value void, so that no one tries to do so in
the future.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200416145448.GA1380878@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/filesystems/debugfs.rst

@@ -79,8 +79,8 @@ created with any of::
 			   struct dentry *parent, u8 *value);
     void debugfs_create_u16(const char *name, umode_t mode,
 			    struct dentry *parent, u16 *value);
-    struct dentry *debugfs_create_u32(const char *name, umode_t mode,
-				      struct dentry *parent, u32 *value);
+    void debugfs_create_u32(const char *name, umode_t mode,
+			    struct dentry *parent, u32 *value);
     void debugfs_create_u64(const char *name, umode_t mode,
 			    struct dentry *parent, u64 *value);
 

fs/debugfs/file.c

@@ -506,20 +506,11 @@ DEFINE_DEBUGFS_ATTRIBUTE(fops_u32_wo, NULL, debugfs_u32_set, "%llu\n");
  * This function creates a file in debugfs with the given name that
  * contains the value of the variable @value.  If the @mode variable is so
  * set, it can be read from, and written to.
- *
- * This function will return a pointer to a dentry if it succeeds.  This
- * pointer must be passed to the debugfs_remove() function when the file is
- * to be removed (no automatic cleanup happens if your module is unloaded,
- * you are responsible here.)  If an error occurs, ERR_PTR(-ERROR) will be
- * returned.
- *
- * If debugfs is not enabled in the kernel, the value ERR_PTR(-ENODEV) will
- * be returned.
  */
-struct dentry *debugfs_create_u32(const char *name, umode_t mode,
-				 struct dentry *parent, u32 *value)
+void debugfs_create_u32(const char *name, umode_t mode, struct dentry *parent,
+			u32 *value)
 {
-	return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u32,
+	debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u32,
 				   &fops_u32_ro, &fops_u32_wo);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_u32);

include/linux/debugfs.h

@@ -103,8 +103,8 @@ void debugfs_create_u8(const char *name, umode_t mode, struct dentry *parent,
 		       u8 *value);
 void debugfs_create_u16(const char *name, umode_t mode, struct dentry *parent,
 			u16 *value);
-struct dentry *debugfs_create_u32(const char *name, umode_t mode,
-				  struct dentry *parent, u32 *value);
+void debugfs_create_u32(const char *name, umode_t mode, struct dentry *parent,
+			u32 *value);
 void debugfs_create_u64(const char *name, umode_t mode, struct dentry *parent,
 			u64 *value);
 struct dentry *debugfs_create_ulong(const char *name, umode_t mode,
@@ -250,12 +250,8 @@ static inline void debugfs_create_u8(const char *name, umode_t mode,
 static inline void debugfs_create_u16(const char *name, umode_t mode,
 				      struct dentry *parent, u16 *value) { }
 
-static inline struct dentry *debugfs_create_u32(const char *name, umode_t mode,
-						struct dentry *parent,
-						u32 *value)
-{
-	return ERR_PTR(-ENODEV);
-}
+static inline void debugfs_create_u32(const char *name, umode_t mode,
+				      struct dentry *parent, u32 *value) { }
 
 static inline void debugfs_create_u64(const char *name, umode_t mode,
 				      struct dentry *parent, u64 *value) { }