From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from relay1.mentorg.com ([192.94.38.131]:64161 "EHLO relay1.mentorg.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751426AbcGBD7r (ORCPT ); Fri, 1 Jul 2016 23:59:47 -0400 Subject: Re: [PATCH 28/38] v4l: Add signal lock status to source change events To: Hans Verkuil , Steve Longerbeam , References: <1465944574-15745-1-git-send-email-steve_longerbeam@mentor.com> <1465944574-15745-29-git-send-email-steve_longerbeam@mentor.com> From: Steve Longerbeam Message-ID: <57773C2F.4040107@mentor.com> Date: Fri, 1 Jul 2016 20:59:43 -0700 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: On 07/01/2016 12:24 AM, Hans Verkuil wrote: > On 06/15/2016 12:49 AM, Steve Longerbeam wrote: >> Add a signal lock status change to the source changes bitmask. >> This indicates there was a signal lock or unlock event detected >> at the input of a video decoder. >> >> Signed-off-by: Steve Longerbeam >> --- >> Documentation/DocBook/media/v4l/vidioc-dqevent.xml | 12 ++++++++++-- >> include/uapi/linux/videodev2.h | 1 + >> 2 files changed, 11 insertions(+), 2 deletions(-) >> >> diff --git a/Documentation/DocBook/media/v4l/vidioc-dqevent.xml b/Documentation/DocBook/media/v4l/vidioc-dqevent.xml >> index c9c3c77..7758ad7 100644 >> --- a/Documentation/DocBook/media/v4l/vidioc-dqevent.xml >> +++ b/Documentation/DocBook/media/v4l/vidioc-dqevent.xml >> @@ -233,8 +233,9 @@ >> >> This event is triggered when a source parameter change is >> detected during runtime by the video device. It can be a >> - runtime resolution change triggered by a video decoder or the >> - format change happening on an input connector. >> + runtime resolution change or signal lock status change >> + triggered by a video decoder, or the format change happening >> + on an input connector. >> This event requires that the id >> matches the input index (when used with a video device node) >> or the pad index (when used with a subdevice node) from which >> @@ -461,6 +462,13 @@ >> from a video decoder. >> >> >> + >> + V4L2_EVENT_SRC_CH_LOCK_STATUS >> + 0x0002 >> + This event gets triggered when there is a signal lock or >> + unlock detected at the input of a video decoder. >> + >> + > I'm not entirely sure I like this. Typically losing lock means that this event > is triggered with the V4L2_EVENT_SRC_CH_RESOLUTION flag set, and userspace has > to check the new timings etc., which will fail if there is no lock anymore. > > This information is also available through ENUMINPUT. > > I would need to know more about why you think this is needed, because I don't > see what this adds. Hi Hans, At least on the ADV718x, a source resolution change (from an autodetected video standard change) and a signal lock status change are distinct events. For example there can be a temporary loss of input signal lock without a change in detected input video standard/resolution. Steve