From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from lists.s-osg.org ([54.187.51.154]:36900 "EHLO lists.s-osg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752483AbaITKDF (ORCPT ); Sat, 20 Sep 2014 06:03:05 -0400 Date: Sat, 20 Sep 2014 07:03:00 -0300 From: Mauro Carvalho Chehab To: James Harper Cc: Hans Verkuil , James Harper , "linux-media@vger.kernel.org" Subject: Re: buffer delivery stops with cx23885 Message-ID: <20140920070300.0558859e@recife.lan> In-Reply-To: <609d00f585384d999c8e3522fe1352ee@SIXPR04MB304.apcprd04.prod.outlook.com> References: <778B08D5C7F58E4D9D9BE1DE278048B5C0B208@maxex1.maxsum.com> <541D469B.4000306@xs4all.nl> <609d00f585384d999c8e3522fe1352ee@SIXPR04MB304.apcprd04.prod.outlook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Em Sat, 20 Sep 2014 09:26:23 +0000 James Harper escreveu: > > > > On 09/20/2014 05:32 AM, James Harper wrote: > > > > > > My cx23885 based DViCO FusionHDTV DVB-T Dual Express2 (I submitted a > > > patch for this a little while ago) has been working great but over > > > the last few months it has started playing up. Nothing has really > > > changed that I can put my finger on. Basically mythtv stops recording > > > after a few minutes sometimes. Rarely when this happens I see some > > > i2c errors but mostly not. > > > > > > With cx23885 debug options turned on (debug=9 vbi_debug=9 > > v4l_debug=9 > > > video_debug=9 irq_debug=9 ci_dbg=9) it seems like the card just stops > > > delivering buffers (see dmesg output following). Well, running the driver with all debugs enabled is a bad idea. The printk mechanism on the Kernel is synchronous (currently - there are some proposals to change it), so it will cause delays. That's specially bad if you're using a serial console (not sure if this is your case). > > > If I stop mythtv, > > > all the buffers are cancelled (cx23885_stop_dma()) etc, and then > > > restarting mythtv will get the recording going again, for a short > > > time (minutes). > > > > > > Any suggestions to where I could start looking? Is it possible that > > > my card itself is broken? (apart from this it's flawless). > > > > I see nothing wrong in the log, but you can try to use the current media_tree > > code. The cx23885's DMA engine has effectively been rewritten there, > > simplifying > > the control flow. > > > > Oops I should have mentioned that. I'm using Debian "Jessie" with 3.16 kernel and already using the latest v4l as per link you sent (my DViCO FusionHDTV DVB-T Dual Express2 patch is in 3.17 I think, but that's not in Debian yet). > > I think it only broke since the rewrite. Before that it seemed to be bulletproof. That was why I asked about the patch just before - I can't tell yet if the driver stops supplying data or if mythtv stops asking for data. If there was something funny about the poll loop then that could cause it. I suppose I can try and go back to an older version of the code and see what happens? > > Would the bug fixed by your "fix VBI/poll regression" patch cause intermittent stalls, or would the application that relied on the missing behaviour simply not work at all? Yes, it may affect. > In any case I've just applied the patch and about to reboot. > > Thanks > > James >