From: alexandre.belloni@free-electrons.com (Alexandre Belloni)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] ARM: at91: at91sam9x5: sets NPCS0 (PA14) back to GPIO
Date: Fri, 25 Jul 2014 10:54:36 +0200 [thread overview]
Message-ID: <20140725085436.GF9532@piout.net> (raw)
In-Reply-To: <53D2174B.4020403@aksignal.cz>
On 25/07/2014 at 10:37:31 +0200, Ji?? Prchal wrote :
>
>
> Dne 25.7.2014 v 10:30 Alexandre Belloni napsal(a):
> >Hi,
> >
> >On 25/07/2014 at 08:14:40 +0200, Ji?? Prchal wrote :
> >>I'm using custom board. My spi node:
> >> spi0: spi at 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 at 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...
--
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
next prev parent reply other threads:[~2014-07-25 8:54 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-07-11 10:22 [PATCH] ARM: at91: at91sam9x5: add clocks for usb device Bo Shen
2014-07-11 10:47 ` Alexandre Belloni
2014-07-11 10:55 ` Jiří Prchal
2014-07-24 13:38 ` [PATCH] ARM: at91: at91sam9x5: sets NPCS0 (PA14) back to GPIO Jiří Prchal
2014-07-24 14:26 ` Boris BREZILLON
2014-07-24 15:06 ` Jiří Prchal
2014-07-24 15:58 ` Boris BREZILLON
2014-07-25 6:14 ` Jiří Prchal
2014-07-25 7:53 ` Boris BREZILLON
2014-07-25 8:27 ` Jiří Prchal
2014-07-25 8:45 ` Boris BREZILLON
2014-07-25 8:54 ` Jiří Prchal
2014-07-25 9:01 ` Boris BREZILLON
2014-07-25 9:13 ` Jiří Prchal
2014-07-25 9:31 ` Boris BREZILLON
2014-07-25 10:06 ` Jiří Prchal
2014-07-25 10:18 ` Boris BREZILLON
2014-07-25 10:32 ` Jiří Prchal
2014-07-25 11:34 ` Boris BREZILLON
2014-07-25 8:33 ` Jiří Prchal
2014-07-25 8:30 ` Alexandre Belloni
2014-07-25 8:36 ` Boris BREZILLON
2014-07-25 8:50 ` Alexandre Belloni
2014-07-25 8:37 ` Jiří Prchal
2014-07-25 8:54 ` Alexandre Belloni [this message]
2014-07-25 8:59 ` Jiří Prchal
2014-07-25 9:02 ` Alexandre Belloni
2014-07-25 9:10 ` Boris BREZILLON
2014-07-25 9:40 ` Jiří Prchal
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