Re: [PATCH 1/5] ARM: dts: at91: sama5d2_ptc_ek: fix sdmmc0 node description

From: <Ludovic.Desroches@microchip.com>
To: <Eugen.Hristev@microchip.com>, <Nicolas.Ferre@microchip.com>,
	<alexandre.belloni@bootlin.com>, <robh+dt@kernel.org>
Cc: <devicetree@vger.kernel.org>, <Tudor.Ambarus@microchip.com>,
	<linux-kernel@vger.kernel.org>, <stable@vger.kernel.org>,
	<linux-arm-kernel@lists.infradead.org>,
	<Codrin.Ciubotariu@microchip.com>,
	<Cristian.Birsan@microchip.com>
Subject: Re: [PATCH 1/5] ARM: dts: at91: sama5d2_ptc_ek: fix sdmmc0 node description
Date: Thu, 2 Apr 2020 10:07:43 +0000	[thread overview]
Message-ID: <5f762bdc-fe07-adbc-af8d-7670b5b4b286@microchip.com> (raw)
In-Reply-To: <b4fe14af-a812-8798-187e-704541a6a75f@microchip.com>

On 4/2/2020 11:20 AM, Eugen Hristev - M18282 wrote:
> On 02.04.2020 01:15, Ludovic Desroches wrote:
>> Remove non-removable and mmc-ddr-1_8v properties from the sdmmc0
>> node which come probably from an unchecked copy/paste.
>>
>> Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
>> Fixes:42ed535595ec "ARM: dts: at91: introduce the sama5d2 ptc ek board"
>> Cc: stable@vger.kernel.org # 4.19 and later
>> ---
>>    arch/arm/boot/dts/at91-sama5d2_ptc_ek.dts | 2 --
>>    1 file changed, 2 deletions(-)
>>
>> diff --git a/arch/arm/boot/dts/at91-sama5d2_ptc_ek.dts b/arch/arm/boot/dts/at91-sama5d2_ptc_ek.dts
>> index 1c24ac8019ba7..772809c54c1f3 100644
>> --- a/arch/arm/boot/dts/at91-sama5d2_ptc_ek.dts
>> +++ b/arch/arm/boot/dts/at91-sama5d2_ptc_ek.dts
>> @@ -125,8 +125,6 @@ sdmmc0: sdio-host@a0000000 {
>>    			bus-width = <8>;
>>    			pinctrl-names = "default";
>>    			pinctrl-0 = <&pinctrl_sdmmc0_default>;
>> -			non-removable;
>> -			mmc-ddr-1_8v;
> 
> Hi Ludovic,
> 
> I am not sure about the removal of mmc-ddr-1_8v; this means eMMCs
> connected on this slot won't work in high speed mode, some people use
> eMMC to SD-Card adapters and stick them into SD-Card slots.
> Would it be a problem to keep this property here ?

Hi Eugen,

It's not a problem to keep it, but I don't think it makes sense. In this 
case mmc-ddr-3_3v should be added too.

Will it work 'out of the box' with any eMMC to SD-Card adapters and 
eMMCs? I remember discussions where we said HW changes were needed to be 
able to select the voltage for the IOs other than using the VDDSEL 
signal of the controller.

Regards

Ludovic

> 
> Thanks,
> Eugen
> 
>>    			status = "okay";
>>    		};
>>    
>>
> 