docs: media: v4l2-ioctl.h: document two global variables

The media kAPI has two global variables at v4l2-ioctl.h. Document
them.

Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <8ebe25ff579962fec09b586f00e77fae7802985f.1765894964.git.mchehab+huawei@kernel.org>

diff --git a/include/media/v4l2-ioctl.h b/include/media/v4l2-ioctl.h
index 6f7a58350441bedf4072d3f13ce05932c4ae8729..54c83b18d555bbd998ce7b596d3366a9dbc58fb7 100644 (file)
--- a/include/media/v4l2-ioctl.h
+++ b/include/media/v4l2-ioctl.h
@@ -663,7 +663,22 @@ void v4l_printk_ioctl(const char *prefix, unsigned int cmd);
 struct video_device;
 
 /* names for fancy debug output */
+
+/**
+ * var v4l2_field_names - Helper array mapping ``V4L2_FIELD_*`` to strings.
+ *
+ * Specially when printing debug messages, it is interesting to output
+ * the field order at the V4L2 buffers. This array associates all possible
+ * values of field pix format from V4L2 API into a string.
+ */
 extern const char *v4l2_field_names[];
+
+/**
+ * var v4l2_type_names - Helper array mapping ``V4L2_BUF_TYPE_*`` to strings.
+ *
+ * When printing debug messages, it is interesting to output the V4L2 buffer
+ * type number with a name that represents its content.
+ */
 extern const char *v4l2_type_names[];
 
 #ifdef CONFIG_COMPAT