[PATCH 1/2] mmc: sdhci: set bus voltage before enabling bus power

Ludovic Desroches ludovic.desroches at atmel.com
Tue Nov 24 01:23:41 PST 2015

Hi Ulf,

On Mon, Nov 09, 2015 at 05:30:26PM +0100, Ludovic Desroches wrote:
> On Mon, Nov 09, 2015 at 05:00:46PM +0100, Ulf Hansson wrote:


> > Now, this discussion was interesting, but I forgot what problem you
> > actually where trying to solve? :-)
> There is this discussion because of two things:
> - Fixing something I consider as a bug: when I have a VMMC, only
>   setting/clearing bit 0. Our controller strictly obeys to the spec and
>   check the 'SD Bus Voltage Select' field. Since we put a reserved value
>   (000), the Power On is not performed.
> - I was trying to get help to understand what is this 'SD Bus Voltage'.
>   For our controller and sdhci_set_power(), it seems to stand for VMMC.
>   For me, everything concerning bus voltage is related to VQMMC, so I was
>   disappointed.

Do you plan to take the patch for VMMC? If yes, I will send a new patch
for the device tree (I'll only add vmmc, not vqmmc as discussed); if
not, forget these two patches.



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