From mboxrd@z Thu Jan 1 00:00:00 1970 From: kishon@ti.com (Kishon Vijay Abraham I) Date: Mon, 11 Jan 2016 14:10:23 +0530 Subject: Nokia N900: u-SD card in v4.2+ In-Reply-To: <201601092344.44641@pali> References: <20160106204627.GA21477@amd> <568DFA4B.7030308@ti.com> <20160107113408.GA26618@amd> <201601092344.44641@pali> Message-ID: <56936A77.9070803@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, On Sunday 10 January 2016 04:14 AM, Pali Roh?r 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 present >>> 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 from >> old kernels don't break their system? > > Please add these selects. I had CONFIG_REGULATOR_PBIAS disabled too, > because I just updated defconfig from older kernel version. 'select' is generally not recommended since it selects a config without caring for the dependency. With adding 'depends on', MMC won't be enabled and will end up in the same problem. Tony has already added a Documentation noting that CONFIG_REGULATOR_PBIAS should be enabled for MMCs to work. commit d8e1f5ed11a39a68da00f05000466c4f6db4456e Author: Tony Lindgren Date: Mon Oct 12 16:19:54 2015 -0700 Documentation: ARM: List new omap MMC requirements Maybe we should also make the error message a little more verbose to tell the user that CONFIG_REGULATOR_PBIAS be selected? Thanks Kishon