[PATCH 6/8] ARM: mvebu: enable SDHCI card detection using DAT3 pin on A388-GP

Marcin Wojtas mw at semihalf.com
Tue Oct 6 00:02:25 PDT 2015


Hi Andrew,

2015-10-06 5:31 GMT+02:00 Andrew Lunn <andrew at lunn.ch>:
> On Tue, Oct 06, 2015 at 03:22:40AM +0200, Marcin Wojtas wrote:
>> The newest revisions of A388-GP (v1.5 and higher) support only
>> DAT3-based card detection, which is enabled by this commit. Hitherto
>> revisions, without such modification, will be impacted with a broken
>> card detection - in order to operate the cards have to be present
>> during kernel boot.
>
> Humm. Is this acceptable, breaking old boards?
>
> I would say at minimum, there should be a big fat comment at the top
> of armada-388-gp.dts explaining that this DTS file is broken on
> v0.0-v1.4.
>
> Or we have two .dts files for the 388-gp file, and a dtsi file.
>

I expected this patch would be controversial, hence I propose a
compromise: set A388-GP SDHCI to 'broken-cd' by defeault. However
Marvell insisted on HW card detection, because software polling spoils
the SD/MMC benchmarks, but this way the user would decide whether to
stay with broken-cd or switch to GPIO/DAT3 detection. What do you
think?

Best regards,
Marcin



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