[PATCH v2 0/8] mmc: dw_mmc-rockchip: allow tuning using the clk-phase api

Doug Anderson dianders at chromium.org
Fri Oct 9 10:19:58 PDT 2015


Hi,

On Fri, Oct 9, 2015 at 1:10 AM, Ulf Hansson <ulf.hansson at linaro.org> wrote:
> Dough, Heiko,
>
> This patchset seems to be causing a boot regression for exynos5800-peach-pi [1].
>
> Apparently, the vmmc regulator doesn't exist for one of the controller
> but vqmmc is. This leads to the following NULL pointer exception.

Ugh.  Hrm, it didn't used to be possible for vmmc to be NULL.  :-/  It
changed in v3.16:

  4d1f52f mmc: core: Improve support for deferred regulators

...and I didn't notice it (most of my development is done on 3.14).  :(


Is it sensible to have vqmmc without vmmc.  One option would be to
change mmc_regulator_get_supply() to not even bother trying to get
vqmmc if vmmc is not there.

Another option would be to just totally fail mmc_regulator_set_vqmmc()
always if vmmc is an error.  ...or assume that any bogus vmmc (either
vmmc is an error or regulator_get_voltage(vmmc) returns an error) is
3.3V?


I guess the safest is to assume that bogus vmmc means 3.3V...


-Doug



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