[HN Gopher] Upgrading my Chumby 8 kernel part 10: RTC
___________________________________________________________________
Upgrading my Chumby 8 kernel part 10: RTC
Author : todsacerdoti
Score : 67 points
Date : 2024-06-02 17:44 UTC (5 hours ago)
(HTM) web link (www.downtowndougbrown.com)
(TXT) w3m dump (www.downtowndougbrown.com)
| fragmede wrote:
| > If you can solve a problem in userspace, why bother force-
| fitting it into the kernel? Chumby probably could have figured
| out a way to make the STM32 show up as an actual /dev/rtc0
| device...but what would the advantage have been over the scripts
| they wrote? None.
|
| For something like the Chumby, where userland is basically fixed
| and doesn't have a half dozen distros building on top of it, I
| agree. But if this were commodity hardware that Debian, Ubuntu,
| Arch, Mint, etc wanted to pull in support for, the extra time
| spent making /dev/rtc0 would mean the distros don't have to
| implement their own non-standard implementation of setting the
| clock.
| dougg3 wrote:
| Author here. That's very much a fair point. I was thinking more
| from the perspective of firmware developers maintaining fixed
| userlands when I wrote that.
|
| It would definitely be an interesting challenge to figure out
| how to multiplex the UART between being a normal UART and
| accesses from an RTC driver in order to allow it to be a real
| RTC!
| kelnos wrote:
| Yeah, I was thinking this too. The benefit of making the STM32
| look like a real RTC to the kernel would mean that userspace
| would Just Work when it came to saving and restoring the time.
| The kernel would restore it on boot using its normal mechanism,
| and the 'hwclock' command would actually work properly, like
| someone unfamiliar with this particular quirk of the hardware
| would expect.
|
| Likely this was a bit easier and faster to implement from the
| perspective of the Chumby folks who were building the system.
| But I've seen enough weird non-standard things done on embedded
| Linux systems (and have unfortunately been involved in
| maintaining one or two of them) to believe that this sort of
| crap is annoying, and wish developers at the manufacturer would
| do things in ways that the platform expects.
| monocasa wrote:
| Even still, I'd love to see more low bandwidth devices use CUSE
| to expose standard device file interfaces.
| dougg3 wrote:
| Interesting, thanks for mentioning CUSE. If I'm understanding
| it correctly, it seems like it would be a perfect solution
| for this. Allows leaving the logic in userspace which is much
| easier to deal with (filesystem access, sharing the UART) but
| would still show up as an RTC device. I may need to play
| further with this!
| traspler wrote:
| I got one of the soft, ball-like chumbys when they came out.
| Really, really amazing design and packaging :) I tried to love it
| as much as it radiated good vibes but sadly from the very
| beginning it was kind of janky and at the time the usefulness was
| not that clear to me. Too bad the cheerfulness of such hardware
| got lost along the way.
| RajT88 wrote:
| I had a Chumby 8 for a while. It was cool - I was able to
| stream TV shows to it using the TVersity flash interface.
|
| It never really got enough software for it to ever get out of
| the "janky and promising" stage.
| sircastor wrote:
| I think the Chumby came out just a little too late. Great idea,
| but like so many things the post-iPhone-smartphone began to
| fill all the roles that those things filled
|
| I was thinking about the brief life of the dedicated flash
| video cameras. They were more capable than phones of the era,
| but they couldn't share on their own.
| duskwuff wrote:
| The Chumby also came out early enough that it had to rely on
| Flash Lite [1] for authoring content. This severely limited
| the audience that could build content for it; if it had came
| out a bit later, with better hardware, it could have
| potentially been used to display HTML content, and things
| might have gone differently.
|
| [1]: https://www.adobe.com/mena_en/products/flashlite/
| userbinator wrote:
| _I was thinking about the brief life of the dedicated flash
| video cameras. They were more capable than phones of the era,
| but they couldn't share on their own._
|
| Those are still used in environments where that is a feature,
| not a bug.
| dang wrote:
| Related:
|
| _Upgrading my Chumby 8 kernel part 7: touchscreen_ -
| https://news.ycombinator.com/item?id=38136590 - Nov 2023 (1
| comment)
|
| _Upgrading my Chumby 8 kernel part 5: graphics_ -
| https://news.ycombinator.com/item?id=36287963 - June 2023 (13
| comments)
|
| _Upgrading my Chumby 8 kernel part 4: reboot /poweroff_ -
| https://news.ycombinator.com/item?id=35184917 - March 2023 (10
| comments)
|
| _Upgrading my old Chumby 8 Linux kernel_ -
| https://news.ycombinator.com/item?id=34063931 - Dec 2022 (32
| comments)
___________________________________________________________________
(page generated 2024-06-02 23:00 UTC)