Hi Steve,

On Friday 13 Jan 2017 15:13:33 Steve Longerbeam wrote:

On 01/13/2017 04:05 AM, Philipp Zabel wrote:

quoted

Am Freitag, den 06.01.2017, 18:11 -0800 schrieb Steve Longerbeam:

quoted

This adds a header file for use by userspace programs wanting to interact
with the i.MX media driver. It defines custom v4l2 controls and events
generated by the i.MX v4l2 subdevices.

Signed-off-by: Steve Longerbeam <redacted>
---

  include/uapi/media/Kbuild |  1 +
  include/uapi/media/imx.h  | 30 ++++++++++++++++++++++++++++++
  2 files changed, 31 insertions(+)
  create mode 100644 include/uapi/media/imx.h

diff --git a/include/uapi/media/Kbuild b/include/uapi/media/Kbuild
index aafaa5a..fa78958 100644
--- a/include/uapi/media/Kbuild
+++ b/include/uapi/media/Kbuild

@@ -1 +1,2 @@

  # UAPI Header export list

+header-y += imx.h

diff --git a/include/uapi/media/imx.h b/include/uapi/media/imx.h
new file mode 100644
index 0000000..2421d9c
--- /dev/null
+++ b/include/uapi/media/imx.h

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2014-2015 Mentor Graphics Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by

the + * Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version
+ */
+
+#ifndef __UAPI_MEDIA_IMX_H__
+#define __UAPI_MEDIA_IMX_H__
+
+/*
+ * events from the subdevs
+ */
+#define V4L2_EVENT_IMX_CLASS          V4L2_EVENT_PRIVATE_START
+#define V4L2_EVENT_IMX_NFB4EOF        (V4L2_EVENT_IMX_CLASS + 1)
+#define V4L2_EVENT_IMX_EOF_TIMEOUT    (V4L2_EVENT_IMX_CLASS + 2)
+#define V4L2_EVENT_IMX_FRAME_INTERVAL (V4L2_EVENT_IMX_CLASS + 3)

Aren't these generic enough to warrant common events? I would think
there have to be other capture IP cores that can signal aborted frames
or frame timeouts.

Yes, agreed. A frame capture timeout, or frame interval error, are
both generic concepts. At some point it would be great to make the
Frame Interval Monitor generally available under v4l2-core. As for the
EOF timeout event, I'll look into moving that into a generic V4L2 event.

I'd prefer generic events if possible, but regardless of whether that's 
possible, the events must be documented in the V4L2 specification.

-- 
Regards,

Laurent Pinchart