From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com (ext-mx07.extmail.prod.ext.phx2.redhat.com [10.5.110.11]) by int-mx04.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o24BTGHW009231 for ; Thu, 4 Mar 2010 06:29:17 -0500 Received: from smtp.positive-internet.com (pop3.positive-internet.com [80.87.128.64]) by mx1.redhat.com (8.13.8/8.13.8) with SMTP id o24BT2Tb028132 for ; Thu, 4 Mar 2010 06:29:03 -0500 Subject: Re: em28xx v4l-info returns gibberish on igepv2 From: John Banks To: Devin Heitmueller In-Reply-To: <829197381003030656q6b5cf73eybcf30b713ba9be37@mail.gmail.com> References: <1267621938.3066.46.camel@chimpin> <829197381003030656q6b5cf73eybcf30b713ba9be37@mail.gmail.com> Date: Thu, 04 Mar 2010 11:29:01 +0000 Message-ID: <1267702141.5175.15.camel@chimpin> Mime-Version: 1.0 Cc: video4linux-list@redhat.com List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: video4linux-list-bounces@redhat.com Errors-To: video4linux-list-bounces@redhat.com List-ID: On Wed, 2010-03-03 at 09:56 -0500, Devin Heitmueller wrote: > On Wed, Mar 3, 2010 at 8:12 AM, John Banks wrote: > > I have an usb capture card that accepts composite and svideo and outputs > > raw video through v4l2. > > > > When running the card on my laptop (ubuntu karmic) I am able to use > > gstreamer to dump the raw video to a file. It comes out as yuv and can > > be easily played back. > > Hi John > > I saw your question on #linuxtv yesterday, and reached out to you but > I guess you didn't see the message. > > I did some ARM work for the em28xx last year, and assuming there has > been no regression, it should be working fine. The fact that even the > enumstd ioctl is returning zero'd data suggests that you've got some > sort of basic userland/kernel communications problem, since that > command has no interaction with the hardware at all (the driver fills > out the result with statically defined data). It might also be some > sort of bug in v4l2-info. > > Have you tried writing a quick 50-line C program that performs the > ioctl and dumps the result? That might help you narrow down whether > it's a v4l2-info problem. > > Without a board though, I'm not quite sure how I could debug this. > > Devin > Hey Devin, Sorry I must have missed your message on irc, I had hung around for most of the day, must have just missed you at the end. Having never used ioctl before I spent most of the day reading up. I created a dump as you suggested and you are right, it seems to be a v4l-info problem. chimp@ll-1:~/source/ioctl$ ./ioctl index: 0 id: 34592 name: NTSC frameperiod-numerator: 1001 frameperiod-denominator: 30000 framelines: 525 reserved: As you can see I get the correct output. I think it has to do with the size of variables created in struct-v4l2.c as they don't match the declaration in videodev2.h Anyway this doesn't help to explain why I get the 0000's seen in the hexdump of the file. I had been hoping that it was incorrectly reading the variables it needed in order for it to create the output correctly. I was originally using the gstreamer v4l2src module that was in the repositories but I tried compiling the gstreamer provided by TI (it contains extra plugins for use on the dsp) but the same problem occurred. If I want to further track down this problem, where should I look? Cheers -- John Banks - Head of Engineering Noonan Media Ltd www.noonanmedia.com MB: +44 779 62 64 707 E: john.banks@noonanmedia.com -- video4linux-list mailing list Unsubscribe mailto:video4linux-list-request@redhat.com?subject=unsubscribe https://www.redhat.com/mailman/listinfo/video4linux-list