From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from perceval.ideasonboard.com ([95.142.166.194]:45833 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754176Ab3AGMSr (ORCPT ); Mon, 7 Jan 2013 07:18:47 -0500 From: Laurent Pinchart To: William Swanson Cc: Mauro Carvalho Chehab , "linux-media@vger.kernel.org" , Ken Petit Subject: Re: [PATCH] omap3isp: Add support for interlaced input data Date: Mon, 07 Jan 2013 13:20:23 +0100 Message-ID: <1489481.HbZGQ48duQ@avalon> In-Reply-To: <50E732FC.10203@fuel7.com> References: <1355796739-2580-1-git-send-email-william.swanson@fuel7.com> <20121227182709.5e89a61a@redhat.com> <50E732FC.10203@fuel7.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 William, On Friday 04 January 2013 11:52:28 William Swanson wrote: > > Laurent Pinchart escreveu: > >> On Monday 17 December 2012 18:12:19 William Swanson wrote: > >>> If the remote video sensor reports an interlaced video mode, the CCDC > >>> block should configure itself appropriately. > >> > >> What will the CCDC do in that case ? Will it capture fields or frames to > >> memory ? If frames, what's the field layout ? You will most likely need > >> to modify ispvideo.c as well, to support interlacing in the V4L2 API, and > >> possibly add interlaced formats support to the media bus API. > > Sorry for the delay in responding; today is my first day back at the > office. I do not know the answers to these questions, and the > documentation doesn't discuss interlacing much. Our application has the > following pipeline: > > composite video -> TVP5146 decoder > -> CCDC parallel interface -> memory -> application > > One of the wires in the parallel interface, cam_fld, indicates the > current field, and this patch simply enables that wire. Without the > patch, every other line in our memory buffer is garbage; with the patch, > the image comes out correctly. What do you get in the memory buffers ? Are fields captured in separate buffers or combined in a single buffer ? If they're combined, are they interleaved or sequential in memory ? > As a matter of fact, an earlier version of the ISP driver actually > contained code for dealing with this flag; it was removed in > cf7a3d91ade6c56bfd860b377f84bd58132f7a81 along with a bunch of other > cleanup work. This patch simply adds the code back, but in a way that is > compatible with the new media pipeline stuff. > > I believe that the CCDC simply captures image data a line at a time and > writes it directly to memory, at least in our use case. The CCDC_SDOFST > register controls the layout, and the default value (which is what the > driver uses now) is basically correct. I am not familiar enough with the > V4L2 architecture to tell you how the driver decides that it now has a > complete frame, or what that even means in an interlaced case. > > On 12/27/2012 12:27 PM, Mauro Carvalho Chehab wrote: > > Btw, you missed to add a Signed-off-by: line on it. > > Oops, this was a problem with my git setup. Both email addresses are > mine; I can re-send the patch with them both set to the same address if > you would prefer that. -- Regards, Laurent Pinchart