Re: [PATCH] ARM: at91: at91sam9x5: sets NPCS0 (PA14) back to GPIO

Jiří Prchal
2014-07-25T08:59:40Z

Dne 25.7.2014 v 10:54 Alexandre Belloni napsal(a):
> On 25/07/2014 at 10:37:31 +0200, Jiří Prchal wrote :
>>
>>
>> Dne 25.7.2014 v 10:30 Alexandre Belloni napsal(a):
>>> Hi,
>>>
>>> On 25/07/2014 at 08:14:40 +0200, Jiří Prchal wrote :
>>>> I'm using custom board. My spi node:
>>>> spi0: spi@f0000000 {
>>>
>>> You should override the pinctrl here as you are using gpios for the cs.
>>> pinctrl-0 = <&pinctrl_spi0_custom>;
>>>
>>>> status = "okay";
>>>> cs-gpios = <&pioA 23 0
>>>> &pioA 22 0
>>>> &pioC 29 0
>>>> &pioA 14 0>;
>>>>
>>>
>>> pinctrl@fffff400 {
>>> spi0 {
>>> pinctrl_spi0_custom: spi0-custom {
>>> atmel,pins =
>>> <AT91_PIOA 23 AT91_PERIPH_GPIO AT91_PINCTRL_NONE>,
>>> <AT91_PIOA 22 AT91_PERIPH_GPIO AT91_PINCTRL_NONE>,
>>> <AT91_PIOC 29 AT91_PERIPH_GPIO AT91_PINCTRL_NONE>,
>>> <AT91_PIOA 14 AT91_PERIPH_GPIO AT91_PINCTRL_NONE>;
>>> };
>>> };
>>> };
>>>
>> Of course, it's the way, but in all other drivers, for example LEDS,
>> it's not needed. And in other way, if I will not use PA14 at all,
>> the pin will goes down every spi transfer.
>
> You must not assumed that the pins are muxed to their default state
> which is gpio and you should set the pinctrl accordingly for each
> device.
>
> If you don't use PA14 at all, then you don't really care about its
> state...
Yes and no, what about on board is populated some chip on PA14, but for some reason at this time I don't need it and not
defined in DT?
>
>