From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lars-Peter Clausen Subject: Re: ASoC: Failed to create DAPM debugfs Date: Thu, 09 Apr 2015 10:29:39 +0200 Message-ID: <55263873.108@metafoo.de> References: <55258272.2010205@metafoo.de> <55262C9D.5080005@metafoo.de> <20150409082246.GB62585@Asurada-CZ80> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: Received: from smtp-out-026.synserver.de (smtp-out-026.synserver.de [212.40.185.26]) by alsa0.perex.cz (Postfix) with ESMTP id 22C412651D2 for ; Thu, 9 Apr 2015 10:29:39 +0200 (CEST) In-Reply-To: <20150409082246.GB62585@Asurada-CZ80> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Nicolin Chen Cc: Russell King , "alsa-devel@alsa-project.org" , Mark Brown , Fabio Estevam , Kuninori Morimoto List-Id: alsa-devel@alsa-project.org On 04/09/2015 10:22 AM, Nicolin Chen wrote: > On Thu, Apr 09, 2015 at 09:39:09AM +0200, Lars-Peter Clausen wrote: > >> The whole thing is a bit confusing. The message you get is what >> you'd get if the 'dapm' sub-directory in the card debugfs directory >> can not be created. One of the few reasons why it would fail is if >> it already existed, but we should never register two dapm contexts >> for the card, so that's a bit strange. One of the few reasons I can >> imagine this could happen is if the parent directory could not be >> created and now we try to create multiple dapm directories at the >> top-level. >> >> Try to do some more debugging and see why and where exactly things >> go wrong. Can you also try this: >> >> diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c >> index b6f8820..7810262 100644 >> --- a/sound/soc/soc-dapm.c >> +++ b/sound/soc/soc-dapm.c >> @@ -1898,6 +1898,11 @@ >> { >> struct dentry *d; >> >> + if (!parent) { >> + dev_warn(dapm->dev, "No debugfs parent!\n"); > > I tried, yes, the parent is NULL. And I did a little tracing and found > that the card->debugfs_root, which is NULL, should be initialized in > the soc_init_card_debugfs() while snd_soc_dapm_debugfs_init() seems > to access this card->debugfs_root before calling soc_init_card_debugfs(). > > I think I must have missed something over here.... Looks like this is the culprit: http://git.kernel.org/cgit/linux/kernel/git/broonie/sound.git/commit/?h=for-next&id=4e2576bd36a12e78ac3786d05b99a820dffe687f