Re: [PATCH v2] mmc: sdhci: add quirk for broken write protect detection

[Eli Billauer]

Hello Michal.

The Zybo board doesn't have any WP pin connected to the MicroSD card. 
There is no physical possibility for the processor to know whether the 
card is write-protected or not.

As I mentioned earlier, the practical problem can be worked around by 
inverting the polarity of the WP bit, using wp-inverted. Practically 
speaking, there's no need for this patch.

I insisted on this patch, because I think that the device tree should 
reflect the hardware as it is, and not contain tricks for fooling the 
driver into doing what we want. But I guess this wasn't a reason good 
enough for adding yet another quirk (to the existing 38 or so).

Regards,
   Eli

On 20/03/14 14:26, Michal Simek wrote:
> we have got this from Mike (we couldn't reply because he has lost this email
> thread.
>
> Mike:
> "I think I found the issue. In ps7_init.c as generated by the tools, it sets the "WP" pin not to EMIO, but to MIO 0. We use pin 0 for a status LED.
>
> # devmem 0XF8000830
> 0x002E0000
>
> Register 0XF8000830 is SD0_WP_CD_SEL, and 0x002E0000 sets CD to pin 46 and WP to pin "0", not to EMIO as I specified in the design.
> "
>
> Eli: Maybe you have the same issue as Mike. Can you please check it?
>    


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