Re: [PATCH v2 2/3] ARM: dts: exynos: Define vqmmc for eMMC card on Odroid X/X2/U3

[Javier Martinez Canillas]

Hello Krzysztof,

On 04/27/2016 10:00 AM, Krzysztof Kozlowski wrote:
> The eMMC card vmmc-supply contained incorrectly two regulators: LDO20
> and buck8. The second one is ignored. Additionally the buck8 is a vqmmc
> supply only on X and X2. On U3 the buck8 is providing power to the LAN
> (SMSC95xx) so instead the LDO22 should be used.
> 
> Fix this by defining proper vmmc and vqmmc supplies for respective
> boards.
> 
> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
> 
> ---
> 
> Changes since v1:
> 1. buck8 is used on X/X2 so differentiate the configuration (hint by
>    Tobias Jakobi).
> ---
>  arch/arm/boot/dts/exynos4412-odroid-common.dtsi | 13 ++++++++++---
>  arch/arm/boot/dts/exynos4412-odroidu3.dts       | 18 ++++++++++++++++++
>  arch/arm/boot/dts/exynos4412-odroidx.dts        | 11 +++++++++++
>  arch/arm/boot/dts/exynos4412-odroidx2.dts       | 11 +++++++++++
>  4 files changed, 50 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/arm/boot/dts/exynos4412-odroid-common.dtsi b/arch/arm/boot/dts/exynos4412-odroid-common.dtsi
> index 3d0d44581fbd..34a5b3daced0 100644
> --- a/arch/arm/boot/dts/exynos4412-odroid-common.dtsi
> +++ b/arch/arm/boot/dts/exynos4412-odroid-common.dtsi
> @@ -347,6 +347,13 @@
>  				regulator-boot-on;
>  			};
>  
> +			ldo22_reg: LDO22 {
> +				regulator-name = "LDO22";
> +				regulator-min-microvolt = <800000>;
> +				regulator-max-microvolt = <3950000>;
> +				regulator-boot-on;
> +			};
> +

I don't have a datasheet for the max77686 but I guess these min and max
values are the actual voltage range that the ldo22 regulator can support?

If that's the case, then I don't think setting these are correct since the
DT binding says that the regulator-{min,max}-microvolt properties describe
the voltage range that consumers may set. I've seen Mark mention this many
times, the last one I remember is at [0].

Probably would be better to leave the ldo22_reg definition to odroidu3.dts
to avoid setting these constraint in a .dtsi file.

>  			ldo25_reg: LDO25 {
>  				regulator-name = "VDDQ_LCD_1.8V";
>  				regulator-min-microvolt = <1800000>;
> @@ -411,8 +418,8 @@
>  
>  			buck8_reg: BUCK8 {
>  				regulator-name = "BUCK8_2.8V";
> -				regulator-min-microvolt = <2800000>;
> -				regulator-max-microvolt = <2800000>;
> +				regulator-min-microvolt = <750000>;
> +				regulator-max-microvolt = <3900000>;

Same here, since not all boards have the same constraint for this regulator,
it would be better to remove it from the .dtsi and let each dts to define it.

>  			};
>  		};
>  	};
> @@ -456,7 +463,7 @@
>  &mshc_0 {
>  	pinctrl-0 = <&sd4_clk &sd4_cmd &sd4_bus4 &sd4_bus8>;
>  	pinctrl-names = "default";
> -	vmmc-supply = <&ldo20_reg &buck8_reg>;
> +	vmmc-supply = <&ldo20_reg>;
>  	mmc-pwrseq = <&emmc_pwrseq>;
>  	status = "okay";
>  
> diff --git a/arch/arm/boot/dts/exynos4412-odroidu3.dts b/arch/arm/boot/dts/exynos4412-odroidu3.dts
> index dd89f7b37c9f..d73aa6c58fe3 100644
> --- a/arch/arm/boot/dts/exynos4412-odroidu3.dts
> +++ b/arch/arm/boot/dts/exynos4412-odroidu3.dts
> @@ -69,6 +69,24 @@
>  	};
>  };
>  
> +/* Supply for LAN9730/SMSC95xx */
> +&buck8_reg {
> +	regulator-name = "BUCK8_P3V3";

I think it would be better to name it "BUCK8_3.3V" for consistency. 

> +	regulator-min-microvolt = <3300000>;
> +	regulator-max-microvolt = <3300000>;
> +};
> +
> +/* VDDQ for MSHC (eMMC card) */
> +&ldo22_reg {
> +	regulator-name = "LDO22_VDDQ_MMC4_2.8V";
> +	regulator-min-microvolt = <2800000>;
> +	regulator-max-microvolt = <2800000>;
> +};
> +
> +&mshc_0 {
> +	vqmmc-supply = <&ldo22_reg>;
> +};
> +
>  &pwm {
>  	pinctrl-0 = <&pwm0_out>;
>  	pinctrl-names = "default";
> diff --git a/arch/arm/boot/dts/exynos4412-odroidx.dts b/arch/arm/boot/dts/exynos4412-odroidx.dts
> index bf7b21b817e4..2af235151301 100644
> --- a/arch/arm/boot/dts/exynos4412-odroidx.dts
> +++ b/arch/arm/boot/dts/exynos4412-odroidx.dts
> @@ -63,12 +63,23 @@
>  	};
>  };
>  
> +/* VDDQ for MSHC (eMMC card) */
> +&buck8_reg {
> +	regulator-name = "BUCK8_VDDQ_MMC4_2.8V";
> +	regulator-min-microvolt = <2800000>;
> +	regulator-max-microvolt = <2800000>;
> +};
> +
>  &ehci {
>  	port@1 {
>  		status = "okay";
>  	};
>  };
>  
> +&mshc_0 {
> +	vqmmc-supply = <&buck8_reg>;
> +};
> +
>  &pinctrl_1 {
>  	gpio_home_key: home_key {
>  		samsung,pins = "gpx2-2";
> diff --git a/arch/arm/boot/dts/exynos4412-odroidx2.dts b/arch/arm/boot/dts/exynos4412-odroidx2.dts
> index 6e33678562ae..3e3584270e00 100644
> --- a/arch/arm/boot/dts/exynos4412-odroidx2.dts
> +++ b/arch/arm/boot/dts/exynos4412-odroidx2.dts
> @@ -22,6 +22,17 @@
>  	};
>  };
>  
> +/* VDDQ for MSHC (eMMC card) */
> +&buck8_reg {
> +	regulator-name = "BUCK8_VDDQ_MMC4_2.8V";
> +	regulator-min-microvolt = <2800000>;
> +	regulator-max-microvolt = <2800000>;
> +};
> +
> +&mshc_0 {
> +	vqmmc-supply = <&buck8_reg>;
> +};
> +
>  &sound {
>  	simple-audio-card,name = "Odroid-X2";
>  	simple-audio-card,widgets =
> 

Rest looks good, so if you do those changes feel free to add:

Reviewed-by: Javier Martinez Canillas <javier@xxxxxxxxxxxxxxx>

[0]: http://www.spinics.net/lists/linux-omap/msg127035.html

Best regards,
-- 
Javier Martinez Canillas
Open Source Group
Samsung Research America