From mboxrd@z Thu Jan  1 00:00:00 1970
Return-path: <linux-media-owner@vger.kernel.org>
Received: from moutng.kundenserver.de ([212.227.17.10]:57827 "EHLO
	moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1756860Ab1HaQuB (ORCPT
	<rfc822;linux-media@vger.kernel.org>);
	Wed, 31 Aug 2011 12:50:01 -0400
From: Arnd Bergmann <arnd@arndb.de>
To: Luciano Coelho <coelho@ti.com>
Subject: Re: [PATCH] mfd: Combine MFD_SUPPORT and MFD_CORE
Date: Wed, 31 Aug 2011 18:49:37 +0200
Cc: Randy Dunlap <rdunlap@xenotime.net>, 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,
	Jean Delvare <khali@linux-fr.org>,
	Tony Lindgren <tony@atomide.com>,
	Grant Likely <grant.likely@secretlab.ca>
References: <20110829102732.03f0f05d.rdunlap@xenotime.net> <1314643307-17780-1-git-send-email-coelho@ti.com>
In-Reply-To: <1314643307-17780-1-git-send-email-coelho@ti.com>
MIME-Version: 1.0
Content-Type: Text/Plain;
  charset="iso-8859-15"
Content-Transfer-Encoding: 7bit
Message-Id: <201108311849.37273.arnd@arndb.de>
Sender: linux-media-owner@vger.kernel.org
List-ID: <linux-media.vger.kernel.org>

On Monday 29 August 2011, Luciano Coelho wrote:
> From: Randy Dunlap <rdunlap@xenotime.net>
> 
> 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 <rdunlap@xenotime.net>
> Reported-by: Johannes Berg <johannes@sipsolutions.net>
> Cc: Jean Delvare <khali@linux-fr.org>
> Cc: Tony Lindgren <tony@atomide.com>
> Cc: Grant Likely <grant.likely@secretlab.ca>
> Signed-off-by: Luciano Coelho <coelho@ti.com>
> ---
> 
> 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. 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.

	Arnd