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

Alexandre Belloni alexandre.belloni at free-electrons.com
Fri Jul 25 02:02:06 PDT 2014


On 25/07/2014 at 10:59:03 +0200, Jiří Prchal wrote :
> >>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?
> >

If this is really an issue for that chip, I would think that you will
change the bootloader to not mux PA14 to periph A and stop it from
trying to read it like an spi flash ?

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com



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