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

Stephen Warren swarren at wwwdotorg.org
Tue Oct 23 14:42:11 EDT 2012


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 at 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.

> 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?



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