Re: [PATCH v3 15/24] media: Add userspace header file for i.MX

[Steve Longerbeam]

On 01/13/2017 04:05 AM, Philipp Zabel wrote:
> Am Freitag, den 06.01.2017, 18:11 -0800 schrieb Steve Longerbeam:
> > 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 <steve_longerbeam@xxxxxxxxxx>
> > ---
> >   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.

Steve