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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 568C4EB64D9 for ; Sun, 2 Jul 2023 22:28:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc: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=GcUanfx61IH25BLORERIwhQHJvlo5TnR9j3SQD0yS5s=; b=k5jooCk8xZLRPZ dRa+tsXYthiCC/CY1S70v39Uf5GUyALshQSPTn259yeG0jSMJZqA3JndT1Dv46fT6+FxUhNmye5Oq mOt9Jla9Kvngncyg4VX0pLXWaqwzO+zpohVpMwQ8uSiYaY/Xz+NmYEy75loLClLe15bUNmqR9SzEr TQyTun++JZVQDyi+q3eOHkTRjnacY0XkoPjkLwsoypWO8iBS4OjesAAxsZ0n5EGE+oqiQKsL7SYSe daRecZKiOgxxbwzDsqWj+1Z46n558ycPxEwqrzoYPXPRzd9IR0rpVl/M3SCUiwuNxQEV9M40j0bs9 887V3NBe92YSLU/Ft78g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qG5Y7-008kxm-0A; Sun, 02 Jul 2023 22:28:07 +0000 Received: from perceval.ideasonboard.com ([213.167.242.64]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qG5Y4-008kxD-1u; Sun, 02 Jul 2023 22:28:05 +0000 Received: from pendragon.ideasonboard.com (85-160-45-219.reb.o2.cz [85.160.45.219]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id E252A6DE; Mon, 3 Jul 2023 00:27:19 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1688336840; bh=XkF0zOHhROpAoFlaqmgLQgzZVdldtalFw4OSvXP0aN8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=TUj6tKE2Gjdwo+OIwF6bQ1z30sDPB8Em+YpmNP2RWdeacN6uGeCpsD9ps7UF5774g u+dD78HhOMaRjjoTVtxxOLSx8bnybning+dFX5gWQyb+Pi+32cqf833QF5/4MwJPQO 5J3rO7JURTZxleXoSfFIaGE+ssletB8gUNcN6BlU= Date: Mon, 3 Jul 2023 01:28:03 +0300 From: Laurent Pinchart To: Sakari Ailus Cc: Jean-Michel Hautbois , dave.stevenson@raspberrypi.com, devicetree@vger.kernel.org, kernel-list@raspberrypi.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, lukasz@jany.st, mchehab@kernel.org, naush@raspberrypi.com, robh@kernel.org, tomi.valkeinen@ideasonboard.com, bcm-kernel-feedback-list@broadcom.com, stefan.wahren@i2se.com Subject: Re: [PATCH v5 04/11] media: bcm2835-unicam: Add support for CCP2/CSI2 camera interface Message-ID: <20230702222803.GF9285@pendragon.ideasonboard.com> References: <20220208155027.891055-1-jeanmichel.hautbois@ideasonboard.com> <20220208155027.891055-5-jeanmichel.hautbois@ideasonboard.com> <20230702152356.GA16995@pendragon.ideasonboard.com> <20230702214505.GB16995@pendragon.ideasonboard.com> <20230702214711.GC16995@pendragon.ideasonboard.com> <20230702220138.GE9285@pendragon.ideasonboard.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230702_152804_797177_BE013E68 X-CRM114-Status: GOOD ( 27.84 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sun, Jul 02, 2023 at 10:20:29PM +0000, Sakari Ailus wrote: > On Mon, Jul 03, 2023 at 01:01:38AM +0300, Laurent Pinchart wrote: > > > > > > > > If the hardware doesn't support lane remapping for CCP2, then that should > > > > > > > > be reflected in DT bindings, i.e. data-lanes isn't relevant. There's no > > > > > > > > need to check that here. > > > > > > > > > > > > > > Should the above check for CSI-2 be dropped as well then ? > > > > > > > > > > > > Same for CSI-2, too: if there's nothing to configure there (lane remapping) > > > > > > there's no need to validate that part of the DT either. > > > > > > > > > > OK, I'll drop that. > > > > > > > > Actually, I'm wondering if it would make sense to tell the parsing > > > > functions whether lane reordering is supported or not. The checks could > > > > then be moved to the framework. What do you think ? > > > > > > I'm not sure how useful this check would be in the first place: if you have > > > hardware that can reorder the lanes, the framework doesn't know what to > > > check there (if anything) and otherwise there's little point in the > > > entire check. > > > > Isn't it good to tell users that something is wrong instead of accepting > > the invalid configuration and let them wonder why the device isn't > > working ? Users in this case would be system integrators, not end > > users, but we have lots of debugging information in the kernel aimed for > > them already. > > In which of the two cases above the framework could do something useful > there? For devices where you can reorder the lanes or for those where you > can't? For devices where you can't, to detect DT that reorders lanes. -- Regards, Laurent Pinchart _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel