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

[Jaehoon Chung]

On 03/15/2016 09:25 AM, Krzysztof Kozlowski wrote:
> 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).

It's confusing..but it seems that Krzysztof's opinion is right.

Best Regards,
Jaehoon Chung

> 
> The card itself is powered by VDDFLASH_28/MAIN_BAT.
> 
> BR,
> Krzysztof
> 
>