v4l regression: V4L2_CID_[VH]CENTER disappeared without notice.

[David Woodhouse <dwmw2@infradead.org>]

These were removed in commit 26d507fcfef7f7d0cd2eec874a87169cc121c835:
V4L/DVB (7166): [v4l] Add new user class controls and deprecate others

> -#define V4L2_CID_HCENTER               (V4L2_CID_BASE+22)
> -#define V4L2_CID_VCENTER               (V4L2_CID_BASE+23)
> -#define V4L2_CID_LASTP1                        (V4L2_CID_BASE+24) /*
> last CID + 1 */
> +
> +/* Deprecated, use V4L2_CID_PAN_RESET and V4L2_CID_TILT_RESET */
> +#define V4L2_CID_HCENTER_DEPRECATED    (V4L2_CID_BASE+22)
> +#define V4L2_CID_VCENTER_DEPRECATED    (V4L2_CID_BASE+23)

But there was no warning in Documentation/feature-removal-schedule.txt
and I'm receiving reports that it's breaking userspace apps (the
gstreamer-v4l2 plugin breaks in Fedora rawhide). You can't just pull
things from the published userspace API like that.

Please can we revert the addition of _DEPRECATED to these ioctl
definitions. Perhaps we can add a runtime warning if they actually get
used? Or a compile-time warning if we can manage that?

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h
index c141118..4a535ea 100644
--- a/include/linux/videodev2.h
+++ b/include/linux/videodev2.h
@@ -865,9 +865,9 @@ struct v4l2_querymenu
 #define V4L2_CID_HFLIP			(V4L2_CID_BASE+20)
 #define V4L2_CID_VFLIP			(V4L2_CID_BASE+21)
 
-/* Deprecated, use V4L2_CID_PAN_RESET and V4L2_CID_TILT_RESET */
-#define V4L2_CID_HCENTER_DEPRECATED	(V4L2_CID_BASE+22)
-#define V4L2_CID_VCENTER_DEPRECATED	(V4L2_CID_BASE+23)
+/* Deprecated; use V4L2_CID_PAN_RESET and V4L2_CID_TILT_RESET */
+#define V4L2_CID_HCENTER		(V4L2_CID_BASE+22)
+#define V4L2_CID_VCENTER		(V4L2_CID_BASE+23)
 
 #define V4L2_CID_POWER_LINE_FREQUENCY	(V4L2_CID_BASE+24)
 enum v4l2_power_line_frequency {


-- 
dwmw2