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

Arnd Bergmann arnd at arndb.de
Mon Dec 15 13:57:36 PST 2014


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



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