All OMAP platforms: MMC is broken

Tony Lindgren tony at
Tue Oct 6 08:37:11 PDT 2015

* Russell King - ARM Linux <linux at> [151006 08:04]:
> On Tue, Oct 06, 2015 at 02:44:25AM -0700, Tony Lindgren wrote:
> > 
> > Hmm DT-based boot finds the MMC card for LDP, dmesg below from DT boot [1].
> > Looks like you're on on -rc4 and not -rc3. My guess is that MMC is not
> > working for you with DT-based booting because you don't seem to have
> > CONFIG_REGULATOR_PBIAS in your seed config for. Care to try enabling that
> > for both your omap3 and omap4 seed config files?
> This is precisely the kind of crap I'm objecting to.  New kernel versions
> come along, and things break because people add extra Kconfig symbols that
> previous versions did not rely upon - and there's no communication of
> what's required for new kernel versions.
> This stuff needs documenting, so that people are aware what changes they
> need to make - please put something in Documentation/arm/OMAP which
> tracks what new additions are required to the Kconfig to keep things
> working.

Good idea, how about something like the following? AFAIK that's the
only .config option needed as MFD_SYSCON is selected by Kconfig



8< ----------
From: Tony Lindgren <tony at>
Date: Tue, 6 Oct 2015 08:33:16 -0700
Subject: [PATCH] Documentation: ARM: List new omap MMC requirements

Earlier the PBIAS regulator was optional, not so with recent
omap_hsmmc changes. To make things easier for people with
custom .config files, let's add minimal documentation for it
as suggested by Russell King <rmk+kernel at>.

Signed-off-by: Tony Lindgren <tony at>

--- /dev/null
+++ b/Documentation/arm/OMAP/README
@@ -0,0 +1,7 @@
+This file contains documentation for running mainline
+kernel on omaps.
+v4.3+		Update is needed for custom .config files to make sure
+		CONFIG_REGULATOR_PBIAS is enabled for MMC1 to work
+		properly.

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