From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6431FC2BA83 for ; Thu, 13 Feb 2020 12:50:57 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3267C2168B for ; Thu, 13 Feb 2020 12:50:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="iepZzxtK" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3267C2168B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=collabora.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=/uQX6B9ue0rt1U1YdT4YcDfFONyZeJTNlhwH5Pw5Nnc=; b=iepZzxtKGwqehFaElHfV4rqXj ou3ngVhA3Xb6MbkMz+rM41cszEOYL6YmXDS6bV7n3o+S7cjuQO39SUtkVl2SALgxZKm/Wt6D3yn9+ tWcM6nBfZlQiwdbHN3fq3dJuwZYlZ3z5yX6436cr43xLKqCMuzqHd8laiNsa7HPUISOd3OdC9/92P u6pAIsuG4X1luKS5hjTjtTULS65BRxGv1KVpqDHDeKxorTSJV5K+oDAyKtw0ivcvZ+Rie2bA8zacp nGTALacW44TRZgBvwOptQmUzlYa1I5C9k9lZ679rHgdpcQzYJh0dtfGtRlfqjahOo/J+2zqnpE/om 7P7JsvoTA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1j2DxC-0004lU-K9; Thu, 13 Feb 2020 12:50:50 +0000 Received: from bhuna.collabora.co.uk ([2a00:1098:0:82:1000:25:2eeb:e3e3]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1j2Dx9-0004kf-A8; Thu, 13 Feb 2020 12:50:48 +0000 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: dafna) with ESMTPSA id 4200629515E Subject: Re: [PATCH v8 05/14] media: rkisp1: add Rockchip ISP1 subdev driver To: Sakari Ailus References: <20190730184256.30338-1-helen.koike@collabora.com> <20190730184256.30338-6-helen.koike@collabora.com> <20190808091406.GQ21370@paasikivi.fi.intel.com> <20190815082422.GM6133@paasikivi.fi.intel.com> <20190815131748.GS6133@paasikivi.fi.intel.com> <78856358-1afd-31a7-86dd-22f7d6d7fb05@collabora.com> <20200212211317.GD3087@kekkonen.localdomain> From: Dafna Hirschfeld Message-ID: <3bc90001-8ebc-c55f-06b5-bbd6b58fa3cd@collabora.com> Date: Thu, 13 Feb 2020 13:50:41 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <20200212211317.GD3087@kekkonen.localdomain> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200213_045047_483459_1A5DF7DE X-CRM114-Status: GOOD ( 22.41 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, eddie.cai.linux@gmail.com, kernel@collabora.com, heiko@sntech.de, jacob2.chen@rock-chips.com, Dafna Hirschfeld , jeffy.chen@rock-chips.com, zyc@rock-chips.com, linux-kernel@vger.kernel.org, tfiga@chromium.org, Allon Huang , linux-rockchip@lists.infradead.org, Helen Koike , Jacob Chen , hans.verkuil@cisco.com, laurent.pinchart@ideasonboard.com, zhengsq@rock-chips.com, mchehab@kernel.org, ezequiel@collabora.com, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 12.02.20 22:13, Sakari Ailus wrote: > Hi Dafna, > > Apologies for the late reply. I learned the mail had got lost due to mail > server issues. > np:) > On Fri, Jan 31, 2020 at 08:38:34PM +0100, Dafna Hirschfeld wrote: >> Hi, >> I (Dafna Hirschfeld) will work in following months with Helen Koike to fix the issues >> in the TODO file of this driver: drivers/staging/media/rkisp1/TODO >> >> On 15.08.19 15:17, Sakari Ailus wrote: >>> On Thu, Aug 15, 2019 at 11:24:22AM +0300, Sakari Ailus wrote: >>>> Hi Helen, >>>> >>>> On Wed, Aug 14, 2019 at 09:58:05PM -0300, Helen Koike wrote: >>>> >>>> ... >>>> >>>>>>> +static int rkisp1_isp_sd_set_fmt(struct v4l2_subdev *sd, >>>>>>> + struct v4l2_subdev_pad_config *cfg, >>>>>>> + struct v4l2_subdev_format *fmt) >>>>>>> +{ >>>>>>> + struct rkisp1_device *isp_dev = sd_to_isp_dev(sd); >>>>>>> + struct rkisp1_isp_subdev *isp_sd = &isp_dev->isp_sdev; >>>>>>> + struct v4l2_mbus_framefmt *mf = &fmt->format; >>>>>>> + >>>>>> >>>>>> Note that for sub-device nodes, the driver is itself responsible for >>>>>> serialising the access to its data structures. >>>>> >>>>> But looking at subdev_do_ioctl_lock(), it seems that it serializes the >>>>> ioctl calls for subdevs, no? Or I'm misunderstanding something (which is >>>>> most probably) ? >>>> >>>> Good question. I had missed this change --- subdev_do_ioctl_lock() is >>>> relatively new. But setting that lock is still not possible as the struct >> >> 'the struct' - do you mean the 'vdev' struct allocated in >> 'v4l2_device_register_subdev_nodes' ? > > Yes. > >> >>>> is allocated in the framework and the device is registered before the >> >>>> driver gets hold of it. It's a good idea to provide the same serialisation >>>> for subdevs as well. >>>> >>>> I'll get back to this later. >>> >>> The main reason is actually that these ops are also called through the >>> sub-device kAPI, not only through the uAPI, and the locks are only taken >>> through the calls via uAPI. >> >> actually it seems that although 'subdev_do_ioctl_lock' exit, I wonder if >> any subdevice uses that vdev->lock in subdev_do_ioctl_lock. >> It is not initialized in v4l2_device_register_subdev_nodes where the vdev is allocated >> and I wonder if any subdevice actually initialize it somewhere else. For example it is null in this >> driver and in vimc. > > It needs to be set before the video device is registered, so indeed, it > seems no driver can make use it. > >> >>> >>> So adding the locks to uAPI calls alone would not address the issue. >> >> What I can do is add a mutex to every struct of a subdevice and lock it >> at the beginning of each subdevice operation. >> Is this an acceptable solution? > > Please do. That's what other drivers do at the moment as well. > I already sent it as the patchset "media: staging: rkisp1: add serialization to the isp and resizer ops" Thanks, Dafna _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel