Re: User Space GPIO Interrupt programming - GSoC-2018
"Dr. Rolf Jansen" <[email protected]>
| Newsgroups | gmane.os.freebsd.devel.arm |
|---|---|
| Message-ID | <[email protected]> |
Am 27.11.2020 um 15:04 schrieb Ian Lepore <[email protected]>: > On Fri, 2020-11-27 at 10:16 -0700, Ian Lepore wrote: >> On Fri, 2020-11-27 at 14:28 +0300, Vladimir Goncharov wrote: >>> Here it is. >>> There is struct gpioc_event with pin number and bintime which is send >>> to userspace. >>> >>> Also I'm thinking about to implementation notofication without extra >>> reading from socket via struct kevent's extra fields (fflags/ext[4]), >>> looks like it is possible. >>> >> >> Please don't top-post on freebsd mailing lists. >> >> I think we need a way for the app to choose whether it wants simple >> reporting of pin number (like the original code) perhaps along with a >> count, versus requesting detailed per-event data. I'm going to propose >> something more detailed about this as soon as I get my thoughts all >> organized. I also want to get the original code and the locking fixes >> I've done to it into a phab review for people to start looking at >> before starting to do new major changes to it. >> >> Allocating memory in the interrupt handler isn't a good idea, it will >> just increase latency on processing other pin interrupts and lead to >> inaccurate timestamps. IMO, it would be better to allocate a fixed >> array of events; when the app requests detailed event reporting it can >> request the number of stored events it wants handled and we could >> allocate all at once based on that. >> > > The gsoc2018 code, with locking and style(9) fixes, is now at: > > https://reviews.freebsd.org/D27398 I got it working, and as expected, by your comments the level interrupt mode has been disabled. I am OK with this. Later, I will add more comments on this in my response to you other e-mail. Best regards Rolf _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-arm To unsubscribe, send any mail to "[email protected]"