From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfram Sang Date: Mon, 04 Jan 2016 12:48:24 +0000 Subject: [PATCH] soc_camera: cleanup control device on async_unbind Message-Id: <1451911723-10868-1-git-send-email-wsa@the-dreams.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-sh@vger.kernel.org Cc: Wolfram Sang , Guennadi Liakhovetski , Mauro Carvalho Chehab , linux-media@vger.kernel.org From: Wolfram Sang 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] [] (dump_backtrace) from [] (show_stack+0x20/0x24) [ 31.164233] r6:c05c5b33 r5:00000009 r4:00000000 r3:00404100 [ 31.170017] [] (show_stack) from [] (dump_stack+0x78/0x94) [ 31.177344] [] (dump_stack) from [] (warn_slowpath_common+0x98/0xc4) [ 31.185518] r4:00000000 r3:00000000 [ 31.189172] [] (warn_slowpath_common) from [] (warn_slowpath_null+0x2c/0x34) [ 31.198043] r8:eb38df28 r7:eb38c5d0 r6:eb38de80 r5:e6962810 r4:eb38de80 [ 31.204898] [] (warn_slowpath_null) from [] (soc_camera_async_bound+0x40/0xa0) [ 31.213955] [] (soc_camera_async_bound) from [] (v4l2_async_test_notify+0x9c/0x108) [ 31.223430] r5:eb38c5ec r4:eb38de80 [ 31.227084] [] (v4l2_async_test_notify) from [] (v4l2_async_register_subdev+0x88/0xd0) [ 31.236822] r7:c07115c8 r6:c071160c r5:eb38c5ec r4:eb38de80 [ 31.242622] [] (v4l2_async_register_subdev) from [] (adv7180_probe+0x2c8/0x3a4) [ 31.251753] r8:00000000 r7:00000001 r6:eb38de80 r5:ea973400 r4:eb38de10 r3:00000000 [ 31.259660] [] (adv7180_probe) from [] (i2c_device_probe+0x1a0/0x1e4) This gets fixed by clearing the control device pointer on async_unbind. Signed-off-by: Wolfram Sang --- 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