[MinnowBoard] MinnowBoard MAX getting started with GPIO

[David Byte]

I haven't checked all the config options, but openSUSE 13.2 ships a 3.16 
kernel and it loads/boots fine on the Max.

On 11/11/2014 11:22 AM, Darren Hart wrote:
>
> On 11/10/14 16:14, Martin Oldfield wrote:
>> Thanks for the pointers.
>>
>> I compiled a new kernel from the 3.18rc3 source and made some progress.
>>
>> There are now gpio devices in /sys:
>>
>> seabass mjo # ls /sys/class/gpio/
>> export       gpiochip338/ gpiochip382/ gpiochip410/ unexport
>>
>> And you can export things:
>> seabass mjo # echo 338 > /sys/class/gpio/export
>> seabass mjo # ls /sys/class/gpio/
>> export       gpio338/     gpiochip338/ gpiochip382/ gpiochip410/ unexport
>>
>> But the GPIO numbers don't match the documentation:
>> seabass mjo # cat /sys/class/gpio/gpiochip*/base
>> 338
>> 382
>> 410
>> seabass mjo # cat /sys/class/gpio/gpiochip*/ngpio
>> 44
>> 28
>> 102
> Which documentation specifically?
>
> You will see all the GPIO lines and their pinmux configuration (set via
> the firmware lpss config) with:
>
> $ cat /sys/kernel/debug/gpio
>

-- 
David Byte
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SUSE
dbyte at suse.com
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