Re: [PATCH 1/1] mmc: Some microSD cards are not recognized by PCIxx12 SDA controller

[Pierre Ossman <drzeus-list@drzeus.cx>]

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On Tue, 07 Apr 2009 01:30:28 +0200
José Marí­a Fernández González <josemariafg@gmail.com> wrote:

> It is curious. I have concentrated my tests on 2.6.29 with HZ=100 and no preemption, and I have done next tests with my microSD card and laptop:
> 
> *	mmc_delay(2) -> FAIL
> *	mdelay(2) -> FAIL
> *	mmc_delay(10) -> Works!
> *	mdelay(10) -> Works!
> 

Looks good. Although it would have been nice to also know exactly when
it starts working.

> And by mistake I found that:
> 
> *	msleep(2) -> Works!
> 

This is the scheduling effect I was talking about. Basically you can
never get msleep() to delay shorter than 1/HZ seconds.

I'll queue up your patch.

Rgds
-- 
     -- Pierre Ossman

  Linux kernel, MMC maintainer        http://www.kernel.org
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