From: "Niklas Söderlund" <niklas.soderlund@ragnatech.se>
To: Wolfram Sang <wsa@the-dreams.de>
Cc: linux-sh@vger.kernel.org,
Guennadi Liakhovetski <g.liakhovetski@gmx.de>,
Mauro Carvalho Chehab <mchehab@osg.samsung.com>,
linux-media@vger.kernel.org
Subject: Re: [PATCH] soc_camera: cleanup control device on async_unbind
Date: Sun, 07 Feb 2016 13:23:07 +0000 [thread overview]
Message-ID: <20160207132307.GC3717@bigcity.dyn.berto.se> (raw)
In-Reply-To: <1451911723-10868-1-git-send-email-wsa@the-dreams.de>
* Wolfram Sang <wsa@the-dreams.de> [2016-01-04 13:48:24 +0100]:
> From: Wolfram Sang <wsa+renesas@sang-engineering.com>
>
> I got the following WARN on a simple unbind/bind cycle:
>
> root@Lager:/sys/bus/i2c/drivers/adv7180# echo 6-0020 > unbind
> root@Lager:/sys/bus/i2c/drivers/adv7180# echo 6-0020 > bind
> [ 31.097652] adv7180 6-0020: chip found @ 0x20 (e6520000.i2c)
> [ 31.123744] ------------[ cut here ]------------
> [ 31.128413] WARNING: CPU: 3 PID: 873 at drivers/media/platform/soc_camera/soc_camera.c:1463 soc_camera_async_bound+0x40/0xa0()
> [ 31.139896] CPU: 3 PID: 873 Comm: sh Not tainted 4.4.0-rc3-00062-ge8ae2c0b6bca2a #172
> [ 31.147815] Hardware name: Generic R8A7790 (Flattened Device Tree)
> [ 31.154056] Backtrace:
> [ 31.156575] [<c0014bc0>] (dump_backtrace) from [<c0014d80>] (show_stack+0x20/0x24)
> [ 31.164233] r6:c05c5b33 r5:00000009 r4:00000000 r3:00404100
> [ 31.170017] [<c0014d60>] (show_stack) from [<c01e2344>] (dump_stack+0x78/0x94)
> [ 31.177344] [<c01e22cc>] (dump_stack) from [<c0029e7c>] (warn_slowpath_common+0x98/0xc4)
> [ 31.185518] r4:00000000 r3:00000000
> [ 31.189172] [<c0029de4>] (warn_slowpath_common) from [<c0029fa0>] (warn_slowpath_null+0x2c/0x34)
> [ 31.198043] r8:eb38df28 r7:eb38c5d0 r6:eb38de80 r5:e6962810 r4:eb38de80
> [ 31.204898] [<c0029f74>] (warn_slowpath_null) from [<c0356348>] (soc_camera_async_bound+0x40/0xa0)
> [ 31.213955] [<c0356308>] (soc_camera_async_bound) from [<c03499a0>] (v4l2_async_test_notify+0x9c/0x108)
> [ 31.223430] r5:eb38c5ec r4:eb38de80
> [ 31.227084] [<c0349904>] (v4l2_async_test_notify) from [<c0349dd8>] (v4l2_async_register_subdev+0x88/0xd0)
> [ 31.236822] r7:c07115c8 r6:c071160c r5:eb38c5ec r4:eb38de80
> [ 31.242622] [<c0349d50>] (v4l2_async_register_subdev) from [<c0337040>] (adv7180_probe+0x2c8/0x3a4)
> [ 31.251753] r8:00000000 r7:00000001 r6:eb38de80 r5:ea973400 r4:eb38de10 r3:00000000
> [ 31.259660] [<c0336d78>] (adv7180_probe) from [<c032dd80>] (i2c_device_probe+0x1a0/0x1e4)
>
> This gets fixed by clearing the control device pointer on async_unbind.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Tested on Koelsch and the camera works fine after a unbind/bind
operation.
> ---
>
> I stumbled over this while playing with OF_DYNAMIC and rebinding various
> devices through that. I have to admit I am not actually using the camera
> interface besides binding to it. This shouldn't make a difference, though :)
>
> Stable material, I'd think.
>
> drivers/media/platform/soc_camera/soc_camera.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/media/platform/soc_camera/soc_camera.c b/drivers/media/platform/soc_camera/soc_camera.c
> index dc98122e78dc50..361275c9f770d7 100644
> --- a/drivers/media/platform/soc_camera/soc_camera.c
> +++ b/drivers/media/platform/soc_camera/soc_camera.c
> @@ -1493,6 +1493,8 @@ static void soc_camera_async_unbind(struct v4l2_async_notifier *notifier,
> struct soc_camera_async_client, notifier);
> struct soc_camera_device *icd = platform_get_drvdata(sasc->pdev);
>
> + icd->control = NULL;
> +
> if (icd->clk) {
> v4l2_clk_unregister(icd->clk);
> icd->clk = NULL;
> --
> 2.1.4
>
next prev parent reply other threads:[~2016-02-07 13:23 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-04 12:48 [PATCH] soc_camera: cleanup control device on async_unbind Wolfram Sang
2016-01-09 11:29 ` Guennadi Liakhovetski
2016-01-09 13:16 ` Wolfram Sang
2016-01-09 13:19 ` Wolfram Sang
2016-02-07 13:23 ` Niklas Söderlund [this message]
2016-02-07 22:08 ` Wolfram Sang
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