Re: [PATCH 09/10] ARM: dts: Add MSHC2 dt node for SD card for exynos3250-artik5-devel board

[Krzysztof Kozlowski]

On 14.03.2016 19:22, Chanwoo Choi wrote:
> On 2016ë 03ì 14ì 18:44, Krzysztof Kozlowski wrote:
>> On 14.03.2016 17:48, Chanwoo Choi wrote:
>>> On 2016ë 03ì 14ì 17:31, Krzysztof Kozlowski wrote:
>>>> On 14.03.2016 11:04, Chanwoo Choi wrote:
>>>>> From: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
>>>>>
>>>>> This patch adds MSHC (Mobile Storage Host Controller) dt node for
>>>>> Exynos3250 SoC. MSHC is an interface between the system and the SD card
>>>>>
>>>>> Signed-off-by: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
>>>>> Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
>>>>> ---
>>>>>  arch/arm/boot/dts/exynos3250-artik5-devel.dts | 16 ++++++++++++++++
>>>>>  1 file changed, 16 insertions(+)
>>>>>
>>>>> diff --git a/arch/arm/boot/dts/exynos3250-artik5-devel.dts b/arch/arm/boot/dts/exynos3250-artik5-devel.dts
>>>>> index d17c28969118..a371baf8536d 100644
>>>>> --- a/arch/arm/boot/dts/exynos3250-artik5-devel.dts
>>>>> +++ b/arch/arm/boot/dts/exynos3250-artik5-devel.dts
>>>>> @@ -21,6 +21,22 @@
>>>>>  			"samsung,exynos3250", "samsung,exynos3";
>>>>>  };
>>>>>  
>>>>> +&mshc_2 {
>>>>> +	num-slots = <1>;
>>>>> +	cap-sd-highspeed;
>>>>> +	disable-wp;
>>>>> +	card-detect-delay = <200>;
>>>>> +	clock-frequency = <100000000>;
>>>>> +	clock-freq-min-max = <400000 100000000>;
>>>>> +	samsung,dw-mshc-ciu-div = <1>;
>>>>> +	samsung,dw-mshc-sdr-timing = <0 1>;
>>>>> +	samsung,dw-mshc-ddr-timing = <1 2>;
>>>>> +	pinctrl-names = "default";
>>>>> +	pinctrl-0 = <&sd2_cmd &sd2_clk &sd2_cd &sd2_bus1 &sd2_bus4>;
>>>>> +	bus-width = <4>;
>>>>> +	status = "okay";
>>>>
>>>> vqmmc-supply = ldo3?
>>>
>>> ldo3 is always on state because ldo3 is used for various IP in exynos3250.
>>> I think that we had better to remain always on state for ldo3.
>>
>> Yes, I wasn't thinking about toggling ldo3 but about taking the
>> regulator here to model the dependencies between components.
> 
> Okay. I'll add it as following:
> 
> 	vmmc-supply = <&ldo18_reg>;
> 	vqmmc-supply = <&ldo3>;

ldo18 is not used by mshc2. At least my schematics show that LDO3 goes
to DVDD_MMC2 (on different board revision that would be ldo18 instead of
ldo3, but not both).

The card itself is powered by VDDFLASH_28/MAIN_BAT.

BR,
Krzysztof