From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from ffm.saftware.de ([83.141.3.46]:36471 "EHLO ffm.saftware.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753860Ab1HZMNZ (ORCPT ); Fri, 26 Aug 2011 08:13:25 -0400 Message-ID: <4E578DE1.80706@linuxtv.org> Date: Fri, 26 Aug 2011 14:13:21 +0200 From: Andreas Oberritter MIME-Version: 1.0 To: Chris Rankin CC: linux-media@vger.kernel.org, Mauro Carvalho Chehab Subject: Re: Is DVB ioctl FE_SET_FRONTEND broken? References: <1314358307.50448.YahooMailClassic@web121706.mail.ne1.yahoo.com> In-Reply-To: <1314358307.50448.YahooMailClassic@web121706.mail.ne1.yahoo.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: On 26.08.2011 13:31, Chris Rankin wrote: > --- On Fri, 26/8/11, Andreas Oberritter wrote: >> I first thought that you were talking about a >> regression in Linux 3.0.x. > > Heh, yes and no. I am talking about a regression that I am definitely seeing in 3.0.x. However, I cannot say which kernel the problem first appeared in. [...] > Debugging the problem has shown that the first event received after a FE_SET_FRONTEND ioctl() has frequency == 0, which is considered an error. OK, this is actually the problem, which the proposed patch tries to address: https://patchwork.kernel.org/patch/1036132/ What you're observing is the stale data mentioned in the patch description. You should definitely try the patch. >> Yes. The patch is restoring a different old behaviour. The >> behaviour you're referring to has never been in the kernel. ;-) > > Yikes! Documentation bug, anyone? Large parts of the documentation haven't been updated since about 10 years, besides some renamed enums and functions here and there, when it was merged into Linux 2.5. Contributions are welcome, of course. Regards, Andreas