Re: [PATCH v5 1/3] gpio: Cygnus: define Broadcom Cygnus GPIO binding

Arnd Bergmann
2014-12-15T21:58:36Z

On Monday 15 December 2014 13:35:47 Ray Jui wrote:
>
> Like I said previously, dynamic GPIO allocation works fine in the
> kernel, as long as all of our GPIO clients in the kernel use gpiod based
> API, which is what we will enforce going forward. The only problem is
> with some of our customers who use GPIO through sysfs and expect fixed
> global GPIO numbers. Thinking about this more, it's probably not that
> difficult to add a script for those customers to convert/map the GPIO
> numbers based on readings parsed from sysfs, so I guess that's fine.
>

I think we discussed the user space interface a number of times
in the past, but I forgot the outcome. Either there is already
a way to name gpio lines uniquely in sysfs, or there should be
one.

Can you reach the gpio interfaces using /sys/devices/0001234.bus/1234566.gpiocontroller/...?

Arnd