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

From: Chanwoo Choi
Date: Mon Mar 14 2016 - 21:47:02 EST


On 2016ë 03ì 15ì 10:45, Chanwoo Choi wrote:
> On 2016ë 03ì 15ì 09:56, Jaehoon Chung wrote:
>> 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).
>
> ARTIK5 schema document VLDO18 and VLDO3 are connected to DVDD_MMC2_AP.
> But, I'm not sure what is meaning. So, I'll drop the 'vmmc-supply'

VLDO18 is not connected to DVDD_MMC2_AP. It is NC state.
Sorry for confusion.

Best Regards,
Chanwoo Choi

[snip]