Re: [PATCH V2 3/3] mmc: dw_mmc: Dont cut off vqmmc and vmmc

Doug Anderson
2014-08-27T15:52:51Z

Ulf,

On Wed, Aug 27, 2014 at 4:17 AM, Ulf Hansson <ulf.hansson@linaro.org> wrote:
>> Now, we've got MMC_CAP_NEEDS_POLL, so dw_mmc will periodically be
>> called to check the card detect line, but with vmmc and vqmmc off. It
>> will be unable to return a sensible value without actually turning on
>> vmmc and vqmmc.
>
> Currently MMC_CAP_NEEDS_POLL mean the mmc rescan work will reschedule
> itself with HZ interval. This to check for card insert/removal.
>
> Now, mmc_rescan() will, if present, invoke host's ->get_cd() callback
> to check whether it's worth to continue initialization sequence or if
> it should re-schedule itself again.
>
> If your host driver can distinguish whether a card is inserted, which
> in this case are when vccq is turned off, your ->get_cd() callback need
> to return 1. That will allow mmc_rescan() to continue it's
> initialization sequence and do mmc_power_up().

As per my other email, we can't tell whether a card is inserted when
vqmmc is off.

Does this mean that you have removed your objections to a solution
like Yuvaraj has posted? We still need to break it into two patches
(the core part and the dwmmc part), but otherwise is it OK? I can
post the original patch I sent Yuvaraj if it's helpful (or he can just
include my patch as part 1 of his series).

-Doug