From patchwork Fri Jul 3 14:11:40 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Antonio Ospite X-Patchwork-Id: 33960 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n63ECr0P020369 for ; Fri, 3 Jul 2009 14:12:53 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752704AbZGCOMq (ORCPT ); Fri, 3 Jul 2009 10:12:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753806AbZGCOMq (ORCPT ); Fri, 3 Jul 2009 10:12:46 -0400 Received: from smtp-out26.alice.it ([85.33.2.26]:2932 "EHLO smtp-out26.alice.it" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752704AbZGCOMp (ORCPT ); Fri, 3 Jul 2009 10:12:45 -0400 Received: from fbcmmo06.fbc.local ([192.168.184.137]) by smtp-out26.alice.it with Microsoft SMTPSVC(6.0.3790.3959); Fri, 3 Jul 2009 16:12:47 +0200 Received: from FBCMCL01B07.fbc.local ([192.168.171.45]) by fbcmmo06.fbc.local with Microsoft SMTPSVC(6.0.3790.3959); Fri, 3 Jul 2009 16:11:49 +0200 Received: from badebec ([79.3.186.72]) by FBCMCL01B07.fbc.local with Microsoft SMTPSVC(6.0.3790.3959); Fri, 3 Jul 2009 16:11:47 +0200 Date: Fri, 3 Jul 2009 16:11:40 +0200 From: Antonio Ospite To: linux-media@vger.kernel.org Cc: Guennadi Liakhovetski , Robert Jarzmik Subject: Re: pxa_camera: Oops in pxa_camera_probe. Message-Id: <20090703161140.845950e8.ospite@studenti.unina.it> In-Reply-To: <20090701204325.2a277884.ospite@studenti.unina.it> References: <20090701204325.2a277884.ospite@studenti.unina.it> X-Mailer: Sylpheed 2.6.0 (GTK+ 2.16.3; i686-pc-linux-gnu) X-Face: z*RaLf`X<@C75u6Ig9}{oW$H; 1_\2t5)({*|jhM/Vb; ]yA5\I~93>J<_`<4)A{':UrE Mime-Version: 1.0 X-OriginalArrivalTime: 03 Jul 2009 14:11:47.0128 (UTC) FILETIME=[33785B80:01C9FBE8] Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org On Wed, 1 Jul 2009 20:43:25 +0200 Antonio Ospite wrote: > Hi, > > I get this with pxa-camera in mainline linux (from today). > I haven't touched my board code which used to work in 2.6.30 > I think I've tracked down the cause. The board code is triggering a bug in pxa_camera. The same should apply to mioa701 as well. > Linux video capture interface: v2.00 > Unable to handle kernel NULL pointer dereference at virtual address 00000060 > pgd = c0004000 > [00000060] *pgd=00000000 > Internal error: Oops: f5 [#1] PREEMPT > Modules linked in: > CPU: 0 Tainted: G W (2.6.31-rc1-ezxdev #1) > PC is at dev_driver_string+0x0/0x38 > LR is at pxa_camera_probe+0x144/0x428 The offending dev_driver_str() here is the one in the dev_warn() call in mclk_get_divisor(). This is what is happening: in struct pxacamera_platform_data I have: .mclk_10khz = 5000, which makes the > test in mclk_get_divisor() succeed calling dev_warn to report that the clock has been limited, but pcdev->soc_host.dev is still uninitialized at this time. I could lower the value in my platform data and avoid the bug, but it would be good to have this fixed ASAP anyway. The attached rough patch fixes the problem, but you will surely come out with a better one :) Thanks, Antonio mclk_get_divisor uses pcdev->soc_host.dev, make sure it is initialized. Signed-off-by: Antonio Ospite diff --git a/drivers/media/video/pxa_camera.c b/drivers/media/video/pxa_camera.c index 46e0d8a..e048d25 100644 --- a/drivers/media/video/pxa_camera.c +++ b/drivers/media/video/pxa_camera.c @@ -1579,6 +1579,7 @@ static int __devinit pxa_camera_probe(struct platform_device *pdev) pcdev->mclk = 20000000; } + pcdev->soc_host.dev = &pdev->dev; pcdev->mclk_divisor = mclk_get_divisor(pcdev); INIT_LIST_HEAD(&pcdev->capture); @@ -1644,7 +1645,6 @@ static int __devinit pxa_camera_probe(struct platform_device *pdev) pcdev->soc_host.drv_name = PXA_CAM_DRV_NAME; pcdev->soc_host.ops = &pxa_soc_camera_host_ops; pcdev->soc_host.priv = pcdev; - pcdev->soc_host.dev = &pdev->dev; pcdev->soc_host.nr = pdev->id; err = soc_camera_host_register(&pcdev->soc_host);