[PATCH] doc-guide: kernel-doc: tell about object-like macros

[Randy Dunlap]

Since 2014 kernel-doc has supported describing object-like macros
macros but it is not documented anywhere. I should have required
some documentation for it when I merged the patch. :(

There are currently only 3 uses of this (all in DRM headers, in
include/drm/*.h). There have recently been a few other attempts
at using kernel-doc for object-like macros, but they didn't use the
"define" keyword and I mistakenly told them that kernel-doc does
not support such documentation.  :( again.

Add object-like kernel-doc documentation now so that more may know
about it and use it.

Fixes: cbb4d3e6510b ("scripts/kernel-doc: handle object-like macros")
Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Cc: linux-doc@xxxxxxxxxxxxxxx
---
 Documentation/doc-guide/kernel-doc.rst |   21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff -- a/Documentation/doc-guide/kernel-doc.rst b/Documentation/doc-guide/kernel-doc.rst
--- a/Documentation/doc-guide/kernel-doc.rst
+++ b/Documentation/doc-guide/kernel-doc.rst
@@ -341,6 +341,27 @@ Typedefs with function prototypes can al
    */
    typedef void (*type_name)(struct v4l2_ctrl *arg1, void *arg2);
 
+Object-like macro documentation
+-------------------------------
+
+Object-like macros are distinct from function-like macros. They are
+differentiated by whether the macro name is immediately followed by a
+left parenthesis ('(') for function-like macros or not followed by one
+for object-like macros.
+
+Function-like macros are handled like functions by ``scripts/kernel-doc``.
+They may have a parameter list. Object-like macros have do not have a
+parameter list.
+
+The general format of an object-like macro kernel-doc comment is::
+
+  /**
+   * define object_name - Brief description.
+   *
+   * Description of the object.
+   */
+
+
 Highlights and cross-references
 -------------------------------