Re: Interrupts on GPIO (on RPI, specifically, but also in general)

Manuel Bouyer <[email protected]> Fri, 20 Apr 2018 16:37:01 +0200
Newsgroups gmane.os.netbsd.devel.embedded
Message-ID <[email protected]>
On Thu, Apr 19, 2018 at 10:13:32AM -0700, Jason Thorpe wrote:
> 
> 
> > On Apr 19, 2018, at 9:40 AM, Manuel Bouyer <[email protected]> wrote:
> > 
> > The DTB is here to describe the hardware; with hardware such as RPIs
> > we indeed change the hardware when connecting something to the GPIOs or
> > i2c/spi busses. Both sides needs to cooperate and the device tree is there
> > to make the link between the different elements.
> 
> Fair enough, although with something like i2c, I think of it more like ?connecting something to a traditional serial port?.  Is there a tutorial on this that I can read?

Not really, but there is my picbmc example that you found on github.
There is the driver and the device tree here. Also, it's using a GPIO as
interrupt source.

The NetBSD FDT implementation follows the linux specifications, so looking
at Documentation/devicetree/bindings/ in a recent linux tree is usefull,
although sometimes out of date.

-- 
Manuel Bouyer <[email protected]>
     NetBSD: 26 ans d'experience feront toujours la difference
--