Hi Hans, On Fri, Dec 7, 2018 at 12:08 AM Hans Verkuil <hverkuil-cisco@xxxxxxxxx> wrote: > > Mauro raised a number of objections on irc regarding tags: > > https://linuxtv.org/irc/irclogger_log/media-maint?date=2018-12-06,Thu > > I would like to setup an irc meeting to discuss this and come to a > conclusion, since we need to decide this soon since this is critical > for stateless codec support. > > Unfortunately timezone-wise this is a bit of a nightmare. I think > that at least Mauro, myself and Tomasz Figa should be there, so UTC-2, > UTC+1 and UTC+9 (if I got that right). > > I propose 9 AM UTC which I think will work for everyone except Nicolas. > Any day next week works for me, and (for now) as well for Mauro. Let's pick > Monday to start with, and if you want to join in, then let me know. If that > day doesn't work for you, let me know what other days next week do work for > you. 9am UTC (which should be 6pm JST) works for me on any day this week. Best regards, Tomasz > > Regards, > > Hans > > On 12/05/18 11:20, hverkuil-cisco@xxxxxxxxx wrote: > > From: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> > > > > Add support for 'tags' to struct v4l2_buffer. These can be used > > by m2m devices so userspace can set a tag for an output buffer and > > this value will then be copied to the capture buffer(s). > > > > This tag can be used to refer to capture buffers, something that > > is needed by stateless HW codecs. > > > > The new V4L2_BUF_CAP_SUPPORTS_TAGS capability indicates whether > > or not tags are supported. > > > > Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> > > Reviewed-by: Paul Kocialkowski <paul.kocialkowski@xxxxxxxxxxx> > > Reviewed-by: Alexandre Courbot <acourbot@xxxxxxxxxxxx> > > --- > > include/uapi/linux/videodev2.h | 9 ++++++++- > > 1 file changed, 8 insertions(+), 1 deletion(-) > > > > diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h > > index 2db1635de956..9095d7abe10d 100644 > > --- a/include/uapi/linux/videodev2.h > > +++ b/include/uapi/linux/videodev2.h > > @@ -881,6 +881,7 @@ struct v4l2_requestbuffers { > > #define V4L2_BUF_CAP_SUPPORTS_DMABUF (1 << 2) > > #define V4L2_BUF_CAP_SUPPORTS_REQUESTS (1 << 3) > > #define V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS (1 << 4) > > +#define V4L2_BUF_CAP_SUPPORTS_TAGS (1 << 5) > > > > /** > > * struct v4l2_plane - plane info for multi-planar buffers > > @@ -940,6 +941,7 @@ struct v4l2_plane { > > * @length: size in bytes of the buffer (NOT its payload) for single-plane > > * buffers (when type != *_MPLANE); number of elements in the > > * planes array for multi-plane buffers > > + * @tag: buffer tag > > * @request_fd: fd of the request that this buffer should use > > * > > * Contains data exchanged by application and driver using one of the Streaming > > @@ -964,7 +966,10 @@ struct v4l2_buffer { > > __s32 fd; > > } m; > > __u32 length; > > - __u32 reserved2; > > + union { > > + __u32 reserved2; > > + __u32 tag; > > + }; > > union { > > __s32 request_fd; > > __u32 reserved; > > @@ -990,6 +995,8 @@ struct v4l2_buffer { > > #define V4L2_BUF_FLAG_IN_REQUEST 0x00000080 > > /* timecode field is valid */ > > #define V4L2_BUF_FLAG_TIMECODE 0x00000100 > > +/* tag field is valid */ > > +#define V4L2_BUF_FLAG_TAG 0x00000200 > > /* Buffer is prepared for queuing */ > > #define V4L2_BUF_FLAG_PREPARED 0x00000400 > > /* Cache handling flags */ > > >
