From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933117AbdCKSwi (ORCPT ); Sat, 11 Mar 2017 13:52:38 -0500 Received: from pandora.armlinux.org.uk ([78.32.30.218]:57758 "EHLO pandora.armlinux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755409AbdCKSwa (ORCPT ); Sat, 11 Mar 2017 13:52:30 -0500 Date: Sat, 11 Mar 2017 18:51:37 +0000 From: Russell King - ARM Linux To: Steve Longerbeam Cc: Hans Verkuil , robh+dt@kernel.org, mark.rutland@arm.com, shawnguo@kernel.org, kernel@pengutronix.de, fabio.estevam@nxp.com, mchehab@kernel.org, nick@shmanahar.org, markus.heiser@darmarIT.de, p.zabel@pengutronix.de, laurent.pinchart+renesas@ideasonboard.com, bparrot@ti.com, geert@linux-m68k.org, arnd@arndb.de, sudipm.mukherjee@gmail.com, minghsiu.tsai@mediatek.com, tiffany.lin@mediatek.com, jean-christophe.trotin@st.com, horms+renesas@verge.net.au, niklas.soderlund+renesas@ragnatech.se, robert.jarzmik@free.fr, songjun.wu@microchip.com, andrew-ct.chen@mediatek.com, gregkh@linuxfoundation.org, shuah@kernel.org, sakari.ailus@linux.intel.com, pavel@ucw.cz, devel@driverdev.osuosl.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org Subject: Re: [PATCH v5 15/39] [media] v4l2: add a frame interval error event Message-ID: <20170311185137.GE21222@n2100.armlinux.org.uk> References: <1489121599-23206-1-git-send-email-steve_longerbeam@mentor.com> <1489121599-23206-16-git-send-email-steve_longerbeam@mentor.com> <5b0a0e76-2524-4140-5ccc-380a8f949cfa@xs4all.nl> <6b574476-77df-0e25-a4d1-32d4fe0aec12@xs4all.nl> <5d5cf4a4-a4d3-586e-cd16-54f543dfcce9@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5d5cf4a4-a4d3-586e-cd16-54f543dfcce9@gmail.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Mar 11, 2017 at 10:14:49AM -0800, Steve Longerbeam wrote: > On 03/11/2017 03:39 AM, Hans Verkuil wrote: > >It's fine to use an internal event as long as the end-user doesn't > >see it. But if you lose vsyncs, then you never capture another frame, > >right? > > No, that's not correct. By loss of vertical sync, I mean the IPU > captures portions of two different frames, resulting in a permanent > "split image", with one frame containing portions of two consecutive > images. Or, the video rolls continuously, if you remember the old CRT > television sets of yore, it's the same rolling effect. I have seen that rolling effect, but the iMX6 regains correct sync within one complete "roll" just fine here with IMX219. However, it has always recovered. So, I don't think there's a problem with the iMX6 part of the processing, and so I don't think we should cripple the iMX6 capture drivers for this problem. It seems to me that the problem is with the source. -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH v5 15/39] [media] v4l2: add a frame interval error event Date: Sat, 11 Mar 2017 18:51:37 +0000 Message-ID: <20170311185137.GE21222@n2100.armlinux.org.uk> References: <1489121599-23206-1-git-send-email-steve_longerbeam@mentor.com> <1489121599-23206-16-git-send-email-steve_longerbeam@mentor.com> <5b0a0e76-2524-4140-5ccc-380a8f949cfa@xs4all.nl> <6b574476-77df-0e25-a4d1-32d4fe0aec12@xs4all.nl> <5d5cf4a4-a4d3-586e-cd16-54f543dfcce9@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <5d5cf4a4-a4d3-586e-cd16-54f543dfcce9-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Steve Longerbeam Cc: Hans Verkuil , robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, shawnguo-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, kernel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org, fabio.estevam-3arQi8VN3Tc@public.gmane.org, mchehab-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, nick-gcszYUEDH4VrovVCs/uTlw@public.gmane.org, markus.heiser-O6JHGLzbNUwb1SvskN2V4Q@public.gmane.org, p.zabel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org, laurent.pinchart+renesas-ryLnwIuWjnjg/C1BVhZhaw@public.gmane.org, bparrot-l0cyMroinI0@public.gmane.org, geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org, arnd-r2nGTMty4D4@public.gmane.org, sudipm.mukherjee-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, minghsiu.tsai-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, tiffany.lin-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, jean-christophe.trotin-qxv4g6HH51o@public.gmane.org, horms+renesas-/R6kz+dDXgpPR4JQBCEnsQ@public.gmane.org, niklas.soderlund+renesas-1zkq55x86MTxsAP9Fp7wbw@public.gmane.org, robert.jarzmik-GANU6spQydw@public.gmane.org, songjun.wu-UWL1GkI3JZL3oGB3hsPCZA@public.gmane.org, andrew-ct.chen-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org, shuah-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, sakari.ailus-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, pavel-+ZI9xUNit7I@public.gmane.org, devel-gWbeCf7V1WCQmaza687I9mD2FQJk+8+b@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWMP3drIcvDWNA@public.gmane.org List-Id: devicetree@vger.kernel.org On Sat, Mar 11, 2017 at 10:14:49AM -0800, Steve Longerbeam wrote: > On 03/11/2017 03:39 AM, Hans Verkuil wrote: > >It's fine to use an internal event as long as the end-user doesn't > >see it. But if you lose vsyncs, then you never capture another frame, > >right? > > No, that's not correct. By loss of vertical sync, I mean the IPU > captures portions of two different frames, resulting in a permanent > "split image", with one frame containing portions of two consecutive > images. Or, the video rolls continuously, if you remember the old CRT > television sets of yore, it's the same rolling effect. I have seen that rolling effect, but the iMX6 regains correct sync within one complete "roll" just fine here with IMX219. However, it has always recovered. So, I don't think there's a problem with the iMX6 part of the processing, and so I don't think we should cripple the iMX6 capture drivers for this problem. It seems to me that the problem is with the source. -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@armlinux.org.uk (Russell King - ARM Linux) Date: Sat, 11 Mar 2017 18:51:37 +0000 Subject: [PATCH v5 15/39] [media] v4l2: add a frame interval error event In-Reply-To: <5d5cf4a4-a4d3-586e-cd16-54f543dfcce9@gmail.com> References: <1489121599-23206-1-git-send-email-steve_longerbeam@mentor.com> <1489121599-23206-16-git-send-email-steve_longerbeam@mentor.com> <5b0a0e76-2524-4140-5ccc-380a8f949cfa@xs4all.nl> <6b574476-77df-0e25-a4d1-32d4fe0aec12@xs4all.nl> <5d5cf4a4-a4d3-586e-cd16-54f543dfcce9@gmail.com> Message-ID: <20170311185137.GE21222@n2100.armlinux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Sat, Mar 11, 2017 at 10:14:49AM -0800, Steve Longerbeam wrote: > On 03/11/2017 03:39 AM, Hans Verkuil wrote: > >It's fine to use an internal event as long as the end-user doesn't > >see it. But if you lose vsyncs, then you never capture another frame, > >right? > > No, that's not correct. By loss of vertical sync, I mean the IPU > captures portions of two different frames, resulting in a permanent > "split image", with one frame containing portions of two consecutive > images. Or, the video rolls continuously, if you remember the old CRT > television sets of yore, it's the same rolling effect. I have seen that rolling effect, but the iMX6 regains correct sync within one complete "roll" just fine here with IMX219. However, it has always recovered. So, I don't think there's a problem with the iMX6 part of the processing, and so I don't think we should cripple the iMX6 capture drivers for this problem. It seems to me that the problem is with the source. -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net.