Re: [PATCH 1/2] ARM: dt: tegra: Add sdhci regulators

[Marc Dietrich]

On Tuesday 23 October 2012 12:42:11 Stephen Warren wrote:
> On 10/23/2012 12:07 PM, Marc Dietrich wrote:
> > Pavan,
> > 
> > On Tuesday 23 October 2012 12:48:59 Pavan Kunapuli wrote:
> >> Adding vmmc and vmmcq supplies for sdhci nodes
> >> in tegra dt files.
> > 
> > <...>
> > 
> >> diff --git a/arch/arm/boot/dts/tegra20-paz00.dts
> >> b/arch/arm/boot/dts/tegra20-paz00.dts index 6a93d14..e161b65 100644
> >> --- a/arch/arm/boot/dts/tegra20-paz00.dts
> >> +++ b/arch/arm/boot/dts/tegra20-paz00.dts
> >> @@ -422,13 +422,17 @@
> >> 
> >>  		status = "okay";
> >>  		cd-gpios = <&gpio 173 0>; /* gpio PV5 */
> >>  		wp-gpios = <&gpio 57 0>;  /* gpio PH1 */
> >> 
> >> -		power-gpios = <&gpio 169 0>; /* gpio PV1 */
> >> 
> >>  		bus-width = <4>;
> >> 
> >> +		vmmc-supply = <&vddio_sd_reg>;
> >> +		vqmmc-supply = <&vddio_sd_reg>;
> >> 
> >>  	};
> >>  	
> >>  	sdhci@c8000600 {
> >>  	
> >>  		status = "okay";
> >>  		bus-width = <8>;
> >> 
> >> +		vmmc-supply = <&vddio_sdmmc_reg>;
> >> +		vqmmc-supply = <&vddio_sdmmc_reg>;
> > 
> > to make it better, this should be:
> > 
> > vmmc-supply = <&vcore_mmc_reg>; and
> > vqmmc-supply = <&vddio_nand_reg>;
> > 
> > with vcore_mmc_reg is ldo5 and vddio_nand_reg is the fixed regulator
> > below.
> 
> I think for the eMMC (not SD card), the core supply is actually +3vs_s3,
> and hence fixed; it looks like LDO5 used to be used, but they changed
> it. See the note for the VCC connections on the eMMC chip.

yes, you are right. The schematic had a comment that this was changed.

> > By doing so, I get "sdhci-tegra sdhci-tegra.3: could not set regulator OCR
> > (-1)". MMC subsys wants to set ldo5 to 3.3V but it is fixed. I guess
> > that's
> > harmless for now.
> 
> What I mention above might end up fixing that?

yes, it does.

So the original patch is just fine. Sorry for the noise.

Marc

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