From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steve Longerbeam Subject: Re: [PATCH v4 13/36] [media] v4l2: add a frame timeout event Date: Thu, 2 Mar 2017 15:07:21 -0800 Message-ID: <4b2bcee1-8da0-776e-4455-8d8e7a7abf0a@gmail.com> References: <1487211578-11360-1-git-send-email-steve_longerbeam@mentor.com> <1487211578-11360-14-git-send-email-steve_longerbeam@mentor.com> <20170302155342.GJ3220@valkosipuli.retiisi.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20170302155342.GJ3220@valkosipuli.retiisi.org.uk> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: driverdev-devel-bounces@linuxdriverproject.org Sender: "devel" To: Sakari Ailus Cc: mark.rutland@arm.com, andrew-ct.chen@mediatek.com, minghsiu.tsai@mediatek.com, sakari.ailus@linux.intel.com, nick@shmanahar.org, songjun.wu@microchip.com, hverkuil@xs4all.nl, Steve Longerbeam , pavel@ucw.cz, robert.jarzmik@free.fr, devel@driverdev.osuosl.org, markus.heiser@darmarIT.de, laurent.pinchart+renesas@ideasonboard.com, shuah@kernel.org, linux@armlinux.org.uk, geert@linux-m68k.org, linux-media@vger.kernel.org, devicetree@vger.kernel.org, kernel@pengutronix.de, arnd@arndb.de, mchehab@kernel.org, bparrot@ti.com, robh+dt@kernel.org, horms+renesas@verge.net.au, tiffany.lin@mediatek.com, linux-arm-kernel@lists.infradead.org, niklas.soderlund+renesas@ragnatech.se, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, jean-christophe.trotin@st.com, p.zabel@pengutronix.de, fabio.estevam@nxp.com, shawnguo@kernel.org, sudipm.mukherjee@gmail List-Id: devicetree@vger.kernel.org On 03/02/2017 07:53 AM, Sakari Ailus wrote: > Hi Steve, > > On Wed, Feb 15, 2017 at 06:19:15PM -0800, Steve Longerbeam wrote: >> Add a new FRAME_TIMEOUT event to signal that a video capture or >> output device has timed out waiting for reception or transmit >> completion of a video frame. >> >> Signed-off-by: Steve Longerbeam >> --- >> Documentation/media/uapi/v4l/vidioc-dqevent.rst | 5 +++++ >> Documentation/media/videodev2.h.rst.exceptions | 1 + >> include/uapi/linux/videodev2.h | 1 + >> 3 files changed, 7 insertions(+) >> >> diff --git a/Documentation/media/uapi/v4l/vidioc-dqevent.rst b/Documentation/media/uapi/v4l/vidioc-dqevent.rst >> index 8d663a7..dd77d9b 100644 >> --- a/Documentation/media/uapi/v4l/vidioc-dqevent.rst >> +++ b/Documentation/media/uapi/v4l/vidioc-dqevent.rst >> @@ -197,6 +197,11 @@ call. >> the regions changes. This event has a struct >> :c:type:`v4l2_event_motion_det` >> associated with it. >> + * - ``V4L2_EVENT_FRAME_TIMEOUT`` >> + - 7 >> + - This event is triggered when the video capture or output device >> + has timed out waiting for the reception or transmit completion of >> + a frame of video. > > As you're adding a new interface, I suppose you have an implementation > around. How do you determine what that timeout should be? The imx-media driver sets the timeout to 1 second, or 30 frame periods at 30 fps. Steve