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Date: Fri, 13 Jan 2012 16:52:16 +0200 (EET)
From: Aaro Koskinen <aaro.koskinen@nokia.com>
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To: Dmitry Antipov <dmitry.antipov@linaro.org>
cc: linaro-dev@lists.linaro.org, linux-mmc@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mmc: use usleep_range() in mmc_delay()
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Hi,

On Fri, 13 Jan 2012, Dmitry Antipov wrote:
> On 01/13/2012 05:22 PM, Aaro Koskinen wrote:
>
>> Anyway, I think the change is good. On systems with multiple MMC devices
>> the boot/probe can spend 100-200 ms alone just doing busylooping delays. I
>> think e.g. in mmc_rescan() the code uses frequently mmc_delay(10).
>
> I'm worrying about this:
>
> mmc_delay(DIV_ROUND_UP(card->ext_csd.sa_timeout, 10000))
>
> since I have no ideas about typical values for this timeout.
> If it may be too small (<=10 us), using usleep_range() makes no sense.

Hmm, but the code above is rounding it up to at least 1 ms?

A.