From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean Delvare Subject: Re: [PATCH] mfd: Combine MFD_SUPPORT and MFD_CORE Date: Fri, 2 Sep 2011 14:37:13 +0200 Message-ID: <20110902143713.307bbebe@endymion.delvare> References: <20110829102732.03f0f05d.rdunlap@xenotime.net> <1314643307-17780-1-git-send-email-coelho@ti.com> <201108311849.37273.arnd@arndb.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from zone0.gcu-squad.org ([212.85.147.21]:13929 "EHLO services.gcu-squad.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751846Ab1IBMhh (ORCPT ); Fri, 2 Sep 2011 08:37:37 -0400 In-Reply-To: <201108311849.37273.arnd@arndb.de> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Arnd Bergmann Cc: Luciano Coelho , Randy Dunlap , matti.j.aaltonen@nokia.com, johannes@sipsolutions.net, linux-kernel@vger.kernel.org, sameo@linux.intel.com, mchehab@infradead.org, linux-media@vger.kernel.org, linux-omap@vger.kernel.org, Tony Lindgren , Grant Likely Hi Arnd, On Wed, 31 Aug 2011 18:49:37 +0200, Arnd Bergmann wrote: > On Monday 29 August 2011, Luciano Coelho wrote: > > From: Randy Dunlap > > > > Combine MFD_SUPPORT (which only enabled the remainder of the MFD > > menu) and MFD_CORE. This allows other drivers to select MFD_CORE > > without needing to also select MFD_SUPPORT, which fixes some > > kconfig unmet dependency warnings. Modeled after I2C kconfig. > > > > [Forward-ported to 3.1-rc4. This fixes a warning when some drivers, > > such as RADIO_WL1273, are selected, but MFD_SUPPORT is not. -- Luca] > > > > Signed-off-by: Randy Dunlap > > Reported-by: Johannes Berg > > Cc: Jean Delvare > > Cc: Tony Lindgren > > Cc: Grant Likely > > Signed-off-by: Luciano Coelho > > --- > > > > I guess this should fix the problem. I've simple forward-ported > > Randy's patch to the latest mainline kernel. I don't know via which > > tree this should go in, though. > > > > NOTE: I have not tested this very thoroughly. But at least > > omap2plus stuff seems to work okay with this change. MFD_SUPPORT is > > also selected by a couple of "tile" platforms defconfigs, but I guess > > the Kconfig system should take care of it. > > Doing this is a good idea, but incidentally I have just spent some time > with the same problem and ended up with a solution that I like better, > which is removing CONFIG_MFD_SUPPORT altogether. > > The point is that there is no use enabling MFD_CORE if you don't also > enable any of the specific drivers. Same holds for pretty much every subsystem, right? > MFD_SUPPORT was added as a 'menuconfig' > before we had Kconfig warn about broken dependencies, so everything was > fine. Since Kconfig now issues the warnings, I think it would be better > to just turn the MFD menu into a plain 'menu' and remove all the > 'depends on MFD_SUPPORT' and 'select MFD_SUPPORT' lines from the other > Kconfig files. This would make it impossible to turn off all MFD drivers at once. I think this is considered a feature, at least I find it very convenient to be able to "kill" a subsystem completely. And in the past few years many subsystems were turned from menu to menuconfig for this reason. But maybe MFD is a special case here. Anyway, if you want your patch to be applied, you'll have to send it for review first, as at this point all we have is Luciano's proposal. -- Jean Delvare