From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from tex.lwn.net ([70.33.254.29]:49319 "EHLO vena.lwn.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750784AbaLOOEK (ORCPT ); Mon, 15 Dec 2014 09:04:10 -0500 Date: Mon, 15 Dec 2014 09:04:04 -0500 From: Jonathan Corbet To: Geert Uytterhoeven Cc: Mauro Carvalho Chehab , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH/RESEND] [media] VIDEO_CAFE_CCIC should select VIDEOBUF2_DMA_SG Message-ID: <20141215090404.6d5cb86e@lwn.net> In-Reply-To: <1418651737-10016-1-git-send-email-geert@linux-m68k.org> References: <1418651737-10016-1-git-send-email-geert@linux-m68k.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8bit Sender: linux-media-owner@vger.kernel.org List-ID: On Mon, 15 Dec 2014 14:55:37 +0100 Geert Uytterhoeven wrote: > If VIDEO_CAFE_CCIC=y, but VIDEOBUF2_DMA_SG=m: > > drivers/built-in.o: In function `mcam_v4l_open': > mcam-core.c:(.text+0x1c2e81): undefined reference to `vb2_dma_sg_memops' > mcam-core.c:(.text+0x1c2eb0): undefined reference to `vb2_dma_sg_init_ctx' > drivers/built-in.o: In function `mcam_v4l_release': > mcam-core.c:(.text+0x1c34bf): undefined reference to `vb2_dma_sg_cleanup_ctx' I've been mildly resistant to this because I've never figured out how such a configuration can come about. The Cafe chip only appeared in the OLPC XO-1 and cannot even come close to doing S/G I/O. So this patch robs a bit of memory for no use on a platform that can ill afford it. OTOH, the number of people building contemporary kernels for the XO-1 has got to be pretty small. So, in the interest of mollifying randconfig users out there, you can add my: Acked-by: Jonathan Corbet jon