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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,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 2674BC352A4 for ; Wed, 12 Feb 2020 21:15:36 +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 CEB0C206D7 for ; Wed, 12 Feb 2020 21:15:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="F5PV7Jj6" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CEB0C206D7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.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-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=p4zeARZ/bny9Xc0pGj/ipSOucegCMEMpmTlufOmQgwg=; b=F5PV7Jj6ylBr8T 8WCR2QrH+h9xSjpT3dih4Sqx7IOMepwT/bOrw21JPAymK8rHL83JEE7BOd90zS/9/PDmmDTTwhZgC /0kUQlzsjnhWFKvFjF5RZzb+PNPrfJzFedMc/9bt3KqiB3sXQFuFDb3tla423bUrTNACeHeoZql7q 79p/ithMTz2CjSra32eZkDFTIsGiWCiy3PbEWAZpcq5m15LCOm2SYZjNFOCdDqAy1LFwFH58T/SGH Yhz8x3KD419WwUrGVivf8cn6j8d3i0jZ4WsuzX++iXrqFGJu9uXST4adh7zRbzL6LMAbLCaFHh+tu 0TV3fn9i/YuIuDfLnttA==; 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 1j1zM0-0002Yg-QW; Wed, 12 Feb 2020 21:15:28 +0000 Received: from mga04.intel.com ([192.55.52.120]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1j1zLy-00019i-Bm; Wed, 12 Feb 2020 21:15:27 +0000 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 12 Feb 2020 13:13:25 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,434,1574150400"; d="scan'208";a="432449589" Received: from wendeand-mobl.ger.corp.intel.com (HELO kekkonen.fi.intel.com) ([10.252.52.16]) by fmsmga005.fm.intel.com with ESMTP; 12 Feb 2020 13:13:20 -0800 Received: by kekkonen.fi.intel.com (Postfix, from userid 1000) id 0320921D13; Wed, 12 Feb 2020 23:13:17 +0200 (EET) Date: Wed, 12 Feb 2020 23:13:17 +0200 From: Sakari Ailus To: Dafna Hirschfeld Subject: Re: [PATCH v8 05/14] media: rkisp1: add Rockchip ISP1 subdev driver Message-ID: <20200212211317.GD3087@kekkonen.localdomain> 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> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <78856358-1afd-31a7-86dd-22f7d6d7fb05@collabora.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200212_131526_425050_30A8A91B X-CRM114-Status: GOOD ( 25.15 ) 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-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Dafna, Apologies for the late reply. I learned the mail had got lost due to mail server issues. 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. -- Kind regards, Sakari Ailus _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel