Need to mask warranty bit when checking board revision for 64 bit as well

[akumpf]

I upgraded the firmware on a Pi Zero 2 running 64-bit Bullseye, and somehow the "warranty voided" bit got flipped on. Not a big deal, except then my LED code broke because it couldn't find that board revision anymore when using this library.

For 64 bit, I believe the warranty bit is not being masked (via /proc/device-tree/system/linux,revision). Here'e the relevant 2 lines of code that handle that in the 32 bit check.

rpi_ws281x/rpihw.c

Line 576 in 1ba8e38

// Take out warranty and manufacturer bits

And could be added here:

rpi_ws281x/rpihw.c

Line 536 in 1ba8e38

uint32_t hwver = rpi_hw_info[i].hwver;

Could this also be added to the 64 bit revision check as well? Thanks!

[Gadgetoid]

It's broadly my preference to just do away with this cursed hardware revision check nonsense once and for all.

I unfortunately don't have a lot of time to get lost in tweaking & testing the code- if you could figure out where this mask needs to be against your flipped board and raise a PR that would be very helpful.