From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrei Warkentin <andreiw@motorola.com>
Subject: Re: [PATCH v3 01/12] mmc: sdhci: add support for auto CMD23
Date: Sat, 16 Apr 2011 03:20:49 -0500
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To: "Nath, Arindam" <Arindam.Nath@amd.com>
Cc: Subhash Jadavani <subhashj@codeaurora.org>, "linux-mmc@vger.kernel.org" <linux-mmc@vger.kernel.org>

On Sat, Apr 16, 2011 at 1:43 AM, Nath, Arindam <Arindam.Nath@amd.com> wrote:
>> and
>> then sending the CMD23 for multi block read/write. MMC cards also
>> supports
>> CMD23 so in that case again you have to check MMC EXT_CSD register for
>> CMD23
>
> Yes, you are right. I followed the Physical Layer Spec v3.01 as is, so in case the support is needed for MMC cards, we will need to take care of that too.

It's already done. In the block layer. All you need to do is honor
mmc_request->sbc and set Auto-CMD23 and the CMD23 argument.

>> support. All this logic is better be in core/block layer and let
>> core/block
>> layer inform host controller when to send CMD23 and when not to.
>
> Well in that case, Auto CMD23 will never make sense.

I am unsure why you think that. All Auto CMD23 means is that instead
of manually sending CMD23 (and incurring the extra interrupt penalty),
I have the host automatically do it. But this feature should only be
enabled when upper layers care to enabled it. This is what the CMD23
support plumbed in.

A