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=-10.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_PASS, URIBL_BLOCKED autolearn=ham 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 5081FC43387 for ; Tue, 8 Jan 2019 18:49:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 245AC20827 for ; Tue, 8 Jan 2019 18:49:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1546973366; bh=AsQY+3gjCTqOumZxVzn0aXwjO9eCpQizUUzA7OF/B4M=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=P7Y7DxIgSV7iwwdzAw973I+o43bK3kghmnQGKj2vE6B/1Zx+sXYVIeE2fezut1H1B QrGjW68AlB2VfL9dbk2gwBnsEAj6SmMAdS4amap0IUtg1+DK1W9oNzUNHvQHH3022L 9rYWPdDeH0t3dpOC1Kf9/RkBWbfYNC+8jmS8YDrY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728138AbfAHStZ (ORCPT ); Tue, 8 Jan 2019 13:49:25 -0500 Received: from casper.infradead.org ([85.118.1.10]:55992 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727829AbfAHStZ (ORCPT ); Tue, 8 Jan 2019 13:49:25 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:Content-Type: MIME-Version:References:In-Reply-To:Message-ID:Subject:Cc:To:From:Date:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=6lExWkuQjrMMKa/msQhHJQCpUBgjycvpg3BX+QN+CT0=; b=vQ9ChDQwC1mpDn14EWwHQRk5S8 x53NpvX6pwYi34ZnfOYlV1f/TFu7fyR8QwIHl/Ld/hwughCMkd9k3u0tknLH+B/F6xZGRyUDGYg5w vT+vEDEE60hto12qy4pjtVTTfCMEO9n2ut76TeAT4R3VV+ustTJGbuD0K6QEhixJahoiDqssZ7ydx z8Sf7/AXxQPCqdZG06lWavFgBrgdxPk5iIIy2/p/JKDcqUv2GmbRYIgUXRO2PvR2q39WUHh7a+qV6 X840yxo/VXq8JJ6VjNW2Yacn5GbXU69aH/CeaArUZ1eNECsKIk9RRcU2663L6TPW2lnTMhHvXk8t2 9Xdn/w2w==; Received: from 177.41.113.230.dynamic.adsl.gvt.net.br ([177.41.113.230] helo=coco.lan) by casper.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1ggwRG-000466-D3; Tue, 08 Jan 2019 18:49:22 +0000 Date: Tue, 8 Jan 2019 16:49:16 -0200 From: Mauro Carvalho Chehab To: Mikhail Gavrilov Cc: Laurent Pinchart , linux-media@vger.kernel.org Subject: Re: Kernel error "Unknown pixelformat 0x00000000" occurs when I start capture video Message-ID: <20190108164916.55aa9b93@coco.lan> In-Reply-To: References: <386743082.UsI2JZZ8BA@avalon> <32231660.SI74LuYRbz@avalon> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Em Tue, 8 Jan 2019 21:11:41 +0500 Mikhail Gavrilov escreveu: > On Tue, 8 Jan 2019 at 20:57, Laurent Pinchart > wrote: > > > > Thank you. > > > > Your device exposes five formats: YUY2 (YUYV), YV12 (YVU420), NV12, P010 and > > BGR3 (BGR24). They are all supported by V4L2 and the uvcvideo driver except > > for the P010 format. This would be easy to fix in the uvcvideo driver if it > > wasn't for the fact that the P010 format isn't support by V4L2. Adding support > > for it isn't difficult, but I don't have time to do this myself at the moment. > > Would you consider volunteering if I guide you ? :-) > > > > Sure, I'd be happy to help. What is required of me? It shouldn't be hard. First, you need to add the new format at include/uapi/linux/videodev2.h, like this one: #define V4L2_PIX_FMT_YUV420M v4l2_fourcc('Y', 'M', '1', '2') /* 12 YUV420 planar */ Please put it together with the other YUV formats. As the fourcc "P010" was not used on Linux yet, you could use it, e. g., something like: #define V4L2_PIX_FMT_YUV_P10 v4l2_fourcc('P', '0', '1', '0') /* 10 YUV420 planar */ You need then to document it. Each V4L2 format should have a description, like this: https://linuxtv.org/downloads/v4l-dvb-apis-new/uapi/v4l/pixfmt-yuv420m.html This is generated via a text file (using ReST syntax). On the above example, it is produced by this file: https://git.linuxtv.org/media_tree.git/tree/Documentation/media/uapi/v4l/pixfmt-yuv420m.rst Writing it would take a little more time, but, provided that you don't copy what's written from external docs, you could take a look at the Internet for the P010 descriptions, and use the pixfmt-yuy420m.rst file as the basis for a new pixfmt-p010.rst file. This will produce a patch similar to this one: https://git.linuxtv.org/media_tree.git/commit/?id=5df082e2312c Finally, you need to teach the uvc driver that it should report P010 format, instead of 0x00000000, by adding it at uvc_format_desc uvc_fmts, with the corresponding UVC GUID. We usually do this on a separate patch. Something like this: https://git.linuxtv.org/media_tree.git/commit/?id=6ea0d588d35b Once you have the patches, submit it to the ML :-) You could take a look at the LinuxTV wiki page about how to submit, at the developer's section: https://linuxtv.org/wiki/index.php/Developer_section In particular, take a look at "Submitting Your Work" section there. Thanks, Mauro