From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?iso-8859-1?q?P=E9ter_Ujfalusi?= Subject: Re: [PATCH] ASoC: omap-mcbsp: Do not attempt to change DAI sysclk if stream is active Date: Fri, 10 Jun 2011 14:36:52 +0300 Message-ID: <201106101436.53099.peter.ujfalusi@ti.com> References: <1307705335-2836-1-git-send-email-jhnikula@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from arroyo.ext.ti.com (arroyo.ext.ti.com [192.94.94.40]) by alsa0.perex.cz (Postfix) with ESMTP id AB84A243C8 for ; Fri, 10 Jun 2011 13:36:56 +0200 (CEST) In-Reply-To: <1307705335-2836-1-git-send-email-jhnikula@gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org To: Jarkko Nikula Cc: "alsa-devel@alsa-project.org" , Mark Brown , "Girdwood, Liam" , "stable@kernel.org" List-Id: alsa-devel@alsa-project.org On Friday 10 June 2011 14:28:55 Jarkko Nikula wrote: > Attempt to change McBSP CLKS source while another stream is active is not > safe after commit d135865 ("OMAP: McBSP: implement functional clock > switching via clock framework") in 2.6.37. > > CLKS parent clock switching using clock framework have to idle the McBSP > before switching and then activate it again. This short break can cause a > DMA transaction error to already running stream which halts and recovers > only by closing and restarting the stream. > > This goes more fatal after commit e2fa61d ("OMAP3: l3: Introduce > l3-interconnect error handling driver") in 2.6.39 where l3 driver detects a > severe timeout error and does BUG_ON(). > > Fix this by checking is the McBSP active in omap_mcbsp_dai_set_dai_sysclk > before attempting to change any clocking configuration. This test should > have been here just from the beginning anyway. > > Signed-off-by: Jarkko Nikula > Cc: stable@kernel.org Acked-by: Peter Ujfalusi