[PATCH, v1 1/1] gpio: aspeed: Add gpio base address reading

Hongwei Zhang hongweiz at ami.com
Fri Feb 5 11:34:51 EST 2021


> Hello,
> 
> On Thu, 14 Jan 2021, at 09:08, Hongwei Zhang wrote:
> > Add gpio base address reading in the driver; in old code, it just 
> > returns -1 to gpio->chip.base.
> 
> Why do you want to do this? It feels hacky. The base address only affects the legacy sysfs number-space, 
> and even then if you're using the sysfs interface you can discover the base address for a specific gpiochip 
> via the associated attribute. For example:
> 
> # cat /sys/bus/platform/devices/1e780000.gpio/gpio/gpiochip*/base
> 816
> 
> I feel that you should instead be changing your userspace not to assume a fixed value.
> 
> Finally, the base value is a linux-specific thing and doesn't belong in the devicetree, and if it did, you 
> would also need to update the devicetree binding in Documentation/.
> 
> Cheers,
> 
> Andrew

Hi Andrew,

Thanks for your review and advice.

--Hongwei




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