From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762526AbYD3LzE (ORCPT ); Wed, 30 Apr 2008 07:55:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757635AbYD3Lyw (ORCPT ); Wed, 30 Apr 2008 07:54:52 -0400 Received: from cantor.suse.de ([195.135.220.2]:36221 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758102AbYD3Lyv (ORCPT ); Wed, 30 Apr 2008 07:54:51 -0400 Date: Wed, 30 Apr 2008 13:54:49 +0200 Message-ID: From: Takashi Iwai To: David Miller Cc: mingo@elte.hu, mchehab@infradead.org, akpm@linux-foundation.org, linux-dvb-maintainer@linuxtv.org, video4linux-list@redhat.com, linux-kernel@vger.kernel.org, efault@gmx.de Subject: Re: [patch, -git] media/video/sound build fix, TEA5761/TEA5767 In-Reply-To: <20080430.041703.89847530.davem@davemloft.net> References: <20080430110115.GA5633@elte.hu> <20080430.041703.89847530.davem@davemloft.net> User-Agent: Wanderlust/2.15.5 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.7 (=?ISO-8859-4?Q?Sanj=F2?=) APEL/10.6 MULE XEmacs/21.5 (beta28) (fuki) (+CVS-20070806) (i386-suse-linux) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org At Wed, 30 Apr 2008 04:17:03 -0700 (PDT), David Miller wrote: > > From: Takashi Iwai > Date: Wed, 30 Apr 2008 13:11:31 +0200 > > > IMO, it's the reverse selection from sound to V4L that makes things > > complicated. I believe it's better to fix it as a normal dependency. > > > > How about the patch below? > > The question that remains is what does this mean for users? > > How does a user, who wants to enable this 'sound' driver, > learn that they must enable the v4l subsystem in order to > do so? > > This is typically why select constructs are used, to not bother the > user with such messy details. Yes, from the usability POV, select is better. > But like we see in this case, it can cause serious implementation > problems if not used properly. :( Indeed. The problem is that the select doesn't (can't?) resolve the dependecy in a reverse way. For example, select VIDEO_V4L1 won't turn on the dependent items such as VIDEO_DEV, VIDEO_V4L2_COMMON, VIDEO_ALLOW_V4L1, so and so. Thus, when another dependency is added to the selected target, it can easily break the depdency chain like this case... Takashi