From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from perceval.ideasonboard.com ([95.142.166.194]:59574 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932080AbaDPOJf (ORCPT ); Wed, 16 Apr 2014 10:09:35 -0400 From: Laurent Pinchart To: Arun Kumar K Cc: linux-media@vger.kernel.org, linux-samsung-soc@vger.kernel.org, k.debski@samsung.com, s.nawrocki@samsung.com, hverkuil@xs4all.nl, posciak@chromium.org, arunkk.samsung@gmail.com Subject: Re: [PATCH 1/2] v4l: Add resolution change event. Date: Wed, 16 Apr 2014 16:09:37 +0200 Message-ID: <4943000.PTOl0cPirQ@avalon> In-Reply-To: <1397653162-10179-1-git-send-email-arun.kk@samsung.com> References: <1397653162-10179-1-git-send-email-arun.kk@samsung.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-media-owner@vger.kernel.org List-ID: Hi Arun, Thank you for the patch. On Wednesday 16 April 2014 18:29:21 Arun Kumar K wrote: > From: Pawel Osciak > > This event indicates that the decoder has reached a point in the stream, > at which the resolution changes. The userspace is expected to provide a new > set of CAPTURE buffers for the new format before decoding can continue. > > Signed-off-by: Pawel Osciak > Signed-off-by: Arun Kumar K > --- > .../DocBook/media/v4l/vidioc-subscribe-event.xml | 8 ++++++++ > include/uapi/linux/videodev2.h | 1 + > 2 files changed, 9 insertions(+) > > diff --git a/Documentation/DocBook/media/v4l/vidioc-subscribe-event.xml > b/Documentation/DocBook/media/v4l/vidioc-subscribe-event.xml index > 5c70b61..d848628 100644 > --- a/Documentation/DocBook/media/v4l/vidioc-subscribe-event.xml > +++ b/Documentation/DocBook/media/v4l/vidioc-subscribe-event.xml > @@ -155,6 +155,14 @@ > > > > + V4L2_EVENT_RESOLUTION_CHANGE > + 5 > + This event is triggered when a resolution change is detected > + during runtime by the video decoder. Application may need to > + reinitialize buffers before proceeding further. > + > + Would it make sense to report the new resolution in the event data ? I suppose it might not be available in all cases though. If we can't report it, would it make sense to document how applications should proceed to retrieve it ? A similar resolution change event might be useful on subdevs, in which case we would need to add a pad number to the event data. We could possibly leave that for later, but it would be worth considering the problem already. > + > V4L2_EVENT_PRIVATE_START > 0x08000000 > Base event number for driver-private events. > diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h > index 6ae7bbe..58488b7 100644 > --- a/include/uapi/linux/videodev2.h > +++ b/include/uapi/linux/videodev2.h > @@ -1733,6 +1733,7 @@ struct v4l2_streamparm { > #define V4L2_EVENT_EOS 2 > #define V4L2_EVENT_CTRL 3 > #define V4L2_EVENT_FRAME_SYNC 4 > +#define V4L2_EVENT_RESOLUTION_CHANGE 5 > #define V4L2_EVENT_PRIVATE_START 0x08000000 > > /* Payload for V4L2_EVENT_VSYNC */ -- Regards, Laurent Pinchart