Re: [PATCH 06/15] ARM: dts: ipq4019: Add ipq4019-ap.dk04.dtsi

[Sricharan R]

Hi Abhishek,

On 2/3/2018 4:47 PM, Abhishek Sahu wrote:
> On 2018-01-29 10:41, Sricharan R wrote:
>> Add the common parts for the dk04 boards.
>>
>> Signed-off-by: Sricharan R <sricharan@xxxxxxxxxxxxxx>
>> ---
>> Âarch/arm/boot/dts/qcom-ipq4019-ap.dk04.1.dtsi | 147
> 
> Â<snip>
>> +
>> +ÂÂÂÂÂÂÂÂÂÂÂ nand_pins: nand_pins {
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ pullups {
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ pins = "gpio52", "gpio53",
>> "gpio58",
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ "gpio59";
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ function = "qpic";
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ bias-pull-up;
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ };
>> +
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ pulldowns {
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ pins = "gpio54", "gpio55",
>> "gpio56",
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ "gpio57", "gpio60",
>> "gpio61",
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ "gpio62", "gpio63",
>> "gpio64",
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ "gpio65", "gpio66",
>> "gpio67",
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ "gpio68", "gpio69";
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ function = "qpic";
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ bias-pull-down;
>> +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ };
>> +ÂÂÂÂÂÂÂÂÂÂÂ };
> 
> ÂCan you please check once why do we need pull-up and
> Âpull-down for NAND pins. The NAND chip will be mounted
> Âover board itself so board design should take care of
> Ârequired pull up and pull downs.
> 

  Mostly because, these are always **weak** pull up/down as defaults
  and should be overridden by the ones in the board (if there).


> ÂAlso, some of the above pins like gpio52 will be only used
> Âfor LCD so we can remove those pins. Later on, when LCD
> Âsupport will be added, we can add those pins.
 ok

Regards,
 Sricharan

-- 
"QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation