Re: [PATCH v3 5/13] mmc: sunxi: Mask DATA0 when updating the clock

From	Maxime Ripard <maxime.ripard@free-electrons.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v3 5/13] mmc: sunxi: Mask DATA0 when updating the clock
Date	2017-01-25 10:20 +0100
Message-ID	<t3rUe-8k5-21@gated-at.bofh.it> (permalink)
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On Tue, Jan 24, 2017 at 09:18:46AM +0100, Ulf Hansson wrote:
> On 16 January 2017 at 17:56, Maxime Ripard
> <maxime.ripard@free-electrons.com> wrote:
> > The A64 MMC controllers need DATA0 to be masked while updating the clock,
> > otherwise any subsequent command will result in a timeout.
> 
> Could you elaborate on what mask DATA0 really means? I don't follow.

To be honest, I don't really know :)

This is how it's called both in the vendor tree and the datasheet. I
*think* it might be the first data line on the bus, but I'm not sure
exactly why that would cause any issue when updating the clock.

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com

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Re: [PATCH v3 5/13] mmc: sunxi: Mask DATA0 when updating the clock Ulf Hansson <ulf.hansson@linaro.org> - 2017-01-24 09:20 +0100
  Re: [PATCH v3 5/13] mmc: sunxi: Mask DATA0 when updating the clock Maxime Ripard <maxime.ripard@free-electrons.com> - 2017-01-25 10:20 +0100

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