Re: User Space GPIO Interrupt programming - GSoC-2018

"Dr. Rolf Jansen" <[email protected]>
Newsgroups gmane.os.freebsd.devel.arm
Message-ID <[email protected]>
> Am 24.11.2020 um 17:32 schrieb Ian Lepore <[email protected]>:
> 
> On Tue, 2020-11-24 at 17:14 -0300, Dr. Rolf Jansen wrote:
>> Hello
>> 
>> Has anything of the GSoC-2018 efforts made it into the current code
>> base?
>> 
>> 
> https://wiki.freebsd.org/SummerOfCode2018Projects/UserSpaceGPIOinterrupts
>> 
>> I installed the recent 13.0-CURRENT snapshot (2020-11-19) on a
>> BeagleBone Black which was one of the implementation targets of said
>> project, but when running the test tools, I either see cannot
>> read/kevent/poll/aio_read - Operation not supported by device or
>> Inappropriate ioctl for device.
>> 
>> Perhaps I need to pull the project’s changes into the kernel by
>> myself. However, before this I would like to ask whether it is worth
>> the effort.
>> 
>> Please, can anyone shed some light on this.
>> 
>> Best regards
>> 
>> Rolf
>> 
> 
> I have had that webpage open (but docked) for literally a year,
> eternally hoping that I can find time to get to it and somehow get it
> committed, or maybe use it as the basis for something to be committed
> (I haven't even looked at it close enough to see if it's commit-quality 
> code or what).
> 
> I'm curious: What particular need do you have for userspace gpio
> interrupts?  What would you like the API to look like (do you like the
> things listed at that page, or would you prefer something else)?
> 
> Interrupts is probably not a good name, because it isn't really going
> to act like an interrupt does for kernel code.  It's really just pin-
> change notifications delivered to userland.

I was asked to jump into a project where push buttons and pulses from a rotary encoder (all connected to GPIO's) would invoke some programmed actions. Polling the GPIO's would be too faulty. To me "pin-change notifications delivered to userland" sounds not too bad for my purpose. However, I won't say no for a real threaded GPIO interrupt handler facility, which presumably would serve perfectly as well.

Thank you for answering

Best regards

Rolf
_______________________________________________
[email protected] mailing list
https://lists.freebsd.org/mailman/listinfo/freebsd-arm
To unsubscribe, send any mail to "[email protected]"
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.