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

From Ludovic Desroches <ludovic.desroches@atmel.com>
Newsgroups linux.kernel
Subject Re: [PATCH 1/2] mmc: sdhci: set bus voltage before enabling bus power
Date 2015-11-24 14:20 +0100
Message-ID <qylFL-9v-11@gated-at.bofh.it> (permalink)
References (4 earlier) <qsVVE-7IC-15@gated-at.bofh.it> <qsXb4-dY-5@gated-at.bofh.it> <qsXE6-pE-17@gated-at.bofh.it> <qyi5c-6fp-11@gated-at.bofh.it> <qyjDX-7lE-9@gated-at.bofh.it>
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On Tue, Nov 24, 2015 at 12:01:53PM +0100, Ulf Hansson wrote:
> On 24 November 2015 at 10:23, Ludovic Desroches
> <ludovic.desroches@atmel.com> wrote:
> > 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.
> >
> 
> Which patch do you refer to for "VMMC"?
> 

This one to not write an invalid voltage in the power control register
even if we have an external regulator for vmmc.

Regards

Ludovic
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Thread

Re: [PATCH 1/2] mmc: sdhci: set bus voltage before enabling bus power Ludovic Desroches <ludovic.desroches@atmel.com> - 2015-11-24 10:30 +0100
  Re: [PATCH 1/2] mmc: sdhci: set bus voltage before enabling bus power Ulf Hansson <ulf.hansson@linaro.org> - 2015-11-24 12:10 +0100
    Re: [PATCH 1/2] mmc: sdhci: set bus voltage before enabling bus power Ludovic Desroches <ludovic.desroches@atmel.com> - 2015-11-24 14:20 +0100
      Re: [PATCH 1/2] mmc: sdhci: set bus voltage before enabling bus power Ulf Hansson <ulf.hansson@linaro.org> - 2015-11-24 15:00 +0100
        Re: [PATCH 1/2] mmc: sdhci: set bus voltage before enabling bus power Ludovic Desroches <ludovic.desroches@atmel.com> - 2015-11-24 15:10 +0100
          Re: [PATCH 1/2] mmc: sdhci: set bus voltage before enabling bus power Ulf Hansson <ulf.hansson@linaro.org> - 2015-11-24 16:20 +0100

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