Re: [PATCH V2 1/3] mmc: dw_mmc: use mmc_regulator_get_supply to handle regulators

Doug Anderson
2014-10-01T15:38:19Z

Hi,

On Wed, Oct 1, 2014 at 6:06 AM, Bartlomiej Zolnierkiewicz
<b.zolnierkie@samsung.com> wrote:
>
> Hi,
>
> On Tuesday, September 30, 2014 10:22:34 AM Doug Anderson wrote:
>> Bartlomiej
>>
>> On Mon, Sep 29, 2014 at 5:31 AM, Bartlomiej Zolnierkiewicz
>> <b.zolnierkie@samsung.com> wrote:
>> >
>> > Hi,
>> >
>> > On Friday, August 29, 2014 01:34:44 PM Ulf Hansson wrote:
>> >> On 22 August 2014 15:47, Yuvaraj Kumar C D <yuvaraj.cd@gmail.com> wrote:
>> >> > This patch makes use of mmc_regulator_get_supply() to handle
>> >> > the vmmc and vqmmc regulators.Also it moves the code handling
>> >> > the these regulators to dw_mci_set_ios().It turned on the vmmc
>> >> > and vqmmc during MMC_POWER_UP and MMC_POWER_ON,and turned off
>> >> > during MMC_POWER_OFF.
>> >> >
>> >> > Signed-off-by: Yuvaraj Kumar C D <yuvaraj.cd@samsung.com>
>> >>
>> >> Thanks! Applied for next.
>> >
>> > Unfortunately this patch breaks mmc1 card (Kingston 32GB micro SDHC)
>> > detection on Exynos5420 Arndale Octa for me:
>> >
>> > [ 10.797979] dwmmc_exynos 12220000.mmc: no support for card's volts
>> > [ 10.797998] mmc1: error -22 whilst initialising SD card
>> >
>> > Without the patch:
>> >
>> > [ 10.866926] mmc_host mmc1: Bus speed (slot 0) = 50000000Hz (slot req 50000000Hz, actual 50000000HZ div = 0)
>> > [ 10.866977] mmc1: new high speed SDHC card at address 1234
>> > [ 10.868730] mmcblk1: mmc1:1234 SA32G 29.3 GiB
>> > [ 10.915054] mmcblk1: p1 p2 p3
>> >
>> > The config is attached (exynos_defconfig doesn't work correctly for
>> > this board yet).
>>
>> Yup, this is an expected behavior, unfortunately. This was talked
>> about extensively during the review of this patch series.
>
> Do you mean that a patch with a known regression has been merged
> into next branch of mmc tree? It would be quite sad if it would be
> true.

...so looking at your "dts" file, it looks like this _isn't_ your
problem. Your "vmmc" regulator is listed as "always on", so I believe
that you're OK. Your regulator probably _shouldn't_ be "always on"
(it prevents power cycling the SD card) but right now it's good that
it is...

If any board has a "vmmc" that is not listed as always on then it
would regress with the first two patches applied (and without the
3rd), but there are none that I personally know of that do.