From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: Nokia N900: u-SD card in v4.2+ Date: Wed, 13 Jan 2016 20:12:40 +0100 Message-ID: <20160113191240.GA10717@amd> References: <20160106204627.GA21477@amd> <568DFA4B.7030308@ti.com> <20160107113408.GA26618@amd> <201601092344.44641@pali> <56936A77.9070803@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: <56936A77.9070803@ti.com> Sender: linux-kernel-owner@vger.kernel.org To: Kishon Vijay Abraham I Cc: Pali =?iso-8859-1?Q?Roh=E1r?= , tony@atomide.com, sre@debian.org, sre@ring0.de, kernel list , linux-arm-kernel , linux-omap@vger.kernel.org, khilman@kernel.org, aaro.koskinen@iki.fi, ivo.g.dimitrov.75@gmail.com, patrikbachan@gmail.com List-Id: linux-omap@vger.kernel.org On Mon 2016-01-11 14:10:23, Kishon Vijay Abraham I wrote: > Hi, >=20 > On Sunday 10 January 2016 04:14 AM, Pali Roh=E1r wrote: > > On Thursday 07 January 2016 12:34:09 Pavel Machek wrote: > >> Hi! > >> > >>> On Thursday 07 January 2016 02:16 AM, Pavel Machek wrote: > >>>> Hi! > >>>> > >>>> In v4.1, both internal MMC and u-SD cards work ok. > >>>> > >>>> In v4.2, only the internal MMC is detected. In v4.3, not even > >>>> internal MMC works. In v4.4, only the internal MMC is detected. > >>>> > >>>> Does it work for you? Any patches? > >>> > >>> I don't have Nokia N900 to check this, but can you share your > >>> config and kernel logs? Check if CONFIG_REGULATOR_PBIAS is presen= t > >>> in your config. CONFIG_REGULATOR_PBIAS is now mandatory for all > >>> omap3+ SoCs to work. > >> > >> I enabled CONFIG_REGULATOR_PBIAS and both MMCs now work. > >> > >> I wonder if we should add some selects, so that users updating fro= m > >> old kernels don't break their system? > >=20 > > Please add these selects. I had CONFIG_REGULATOR_PBIAS disabled too= ,=20 > > because I just updated defconfig from older kernel version. >=20 > 'select' is generally not recommended since it selects a config witho= ut > caring for the dependency. With adding 'depends on', MMC won't be ena= bled and > will end up in the same problem. Well... it really should "depend on". Not ideal, but you'll likely realize what went on. Silently compiling known-bad kernel is ... well.. bad. > Tony has already added a Documentation noting that CONFIG_REGULATOR_P= BIAS > should be enabled for MMCs to work. > commit d8e1f5ed11a39a68da00f05000466c4f6db4456e > Author: Tony Lindgren > Date: Mon Oct 12 16:19:54 2015 -0700 >=20 > Documentation: ARM: List new omap MMC requirements >=20 > Maybe we should also make the error message a little more verbose to = tell the > user that CONFIG_REGULATOR_PBIAS be selected? That would help. As would #error if we recognize broken config. Pavel --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses= /blog.html