Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422974Ab3FUOUF (ORCPT ); Fri, 21 Jun 2013 10:20:05 -0400 Received: from mail-oa0-f42.google.com ([209.85.219.42]:34357 "EHLO mail-oa0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1422901Ab3FUOUC (ORCPT ); Fri, 21 Jun 2013 10:20:02 -0400 MIME-Version: 1.0 In-Reply-To: <201306211600.04986.arnd@arndb.de> References: <1371762407-24544-1-git-send-email-joelagnel@ti.com> <51C427E1.2000800@ti.com> <201306211600.04986.arnd@arndb.de> Date: Fri, 21 Jun 2013 09:20:01 -0500 Message-ID: Subject: Re: [PATCH v12 05/11] edma: config: Enable config options for EDMA From: Joel A Fernandes To: Arnd Bergmann Cc: Sekhar Nori , Joel A Fernandes , Tony Lindgren , Matt Porter , Grant Likely , Rob Herring , Vinod Koul , Mark Brown , Benoit Cousson , Russell King , Rob Landley , Andrew Morton , Jason Kridner , Koen Kooi , Devicetree Discuss , Linux OMAP List , Linux ARM Kernel List , Linux DaVinci Kernel List , Linux Kernel Mailing List , Linux Documentation List , Linux MMC List , Linux SPI Devel List Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2314 Lines: 54 On Fri, Jun 21, 2013 at 9:00 AM, Arnd Bergmann wrote: > On Friday 21 June 2013, Joel A Fernandes wrote: >> >> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig >> >> index b1c66a4..7d58cd9 100644 >> >> --- a/arch/arm/Kconfig >> >> +++ b/arch/arm/Kconfig >> >> @@ -841,6 +841,7 @@ config ARCH_DAVINCI >> >> select HAVE_IDE >> >> select NEED_MACH_GPIO_H >> >> select TI_PRIV_EDMA >> >> + select DMADEVICES >> > >> > It is generally a bad idea to force select on something that can be >> > enabled using menuconfig. Unless used carefully, select causes "unmet >> > direct dependency" warnings which folks are already fighting hard to >> > fix. This leads to what Russell referred in the past as "select madness" [1] >> >> Are you concerned with bloat issues? I know your point of view but the idea >> was to build these options by default for these platforms even though >> in some cases >> it might not be used. I have seen folks including myself select the wrong >> option. Having the build system automatically select the correct option for the >> most common cases can be very useful I feel and not require manual >> configuration. > > For defaults, you should use the defconfig, not 'select' in Kconfig. > > A lot of the 'select' statements are actually wrong because they > do not take dependencies into account where A selects B but not C, > and B depends on C, which leads to broken builds when C is disabled > by a user (or randconfig). I haven't come across this problem but- are you saying there is a shortcoming in Kbuild/Kconfig that selects an option even if its dependency is not met? The problem with defconfig is also too many options I feel for a common case. CONFIG_DMADEVICES=y CONFIG_TI_EDMA=y Most if not all future OMAPs from will use EDMA. Why not we can be explicit about it and just built it in anyway. If ARCH_OMAP and DMADEVICES are selected, then we can just build EDMA in by default. I agree maybe the option can be dropped from Davinci but I suggest let's keep it for OMAP. Is that ok? Thanks, Joel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/