BeagleBoneBlack PWM instructions?

[chisleu]

I'm having a heck of a time getting PWM to work. It seems PWM_TEST is disabled on arch linux. I'm entirely unable to figure out how to mux the pins. There are so many conflicting information. Do I really have to recompile a custom patched kernel just to mux the pin type?

I'm so lost. I've tried multiple distros but can't find any of them that:
1) work the same
2) work with PWM's at all

[chisleu]

Apparently you need both a modified version of dtc and customized device tree files.... Totally wish I could just set it through the /sys/ files.

[chisleu]

Angstrom has a functional and patched kernel available. I'm guessing there is simply a lack of interest to hack things like the pwm_test patch instead of waiting for the linux mainline to get the pwm code working correctly with the new interface.

[chisleu]

I'm trying to use abs to not build the kernel now. I'll wiki if I figure anything out.

I got pin muxing to work today, although not for pwm's, thanks to some great videos by Derek Malloy: https://www.youtube.com/watch?v=wui_wU1AeQc

Fantastic video for those of us struggling with device trees. It's disgusting how little information is out there. All the documentation was outdated by the new kernel. Hopefully I can get dtc working with -@. I will document my success.

I found another thread where a guy was in the same boat and said he ran "makepkg --nobuild" and it appeared in the scripts folder. I don't know if it's been updated in the kernel source but not in the AUR package or what. Our Alarm AUR doesn't seem to be capable of letting me flag packages.

I've beat on angstrom for long enough... it's time to get alarm working correctly on the BBB.

[chisleu]

I copied the "dtc" binary from angstrom because I was unable to get it to compile on my BBB.

It allows me to compile dts files to enable the pwm and link them to userland interfaces. However without the pwm_test.c kernel patch, it doesn't seem to accomplish anything. Although I can create a "user interface", it doesn't contain the required period/duty/run files to accomplish anything.