Very simple, work in progress input driver for the SPI keyboard / trackpad found on 12" MacBooks.
To get this driver to work on a 2016 12" MacBook, you'll need to boot the kernel with intremap=nosid. Also, you'll need to modify your DSDT as described by Leif Liddy at https://bugzilla.kernel.org/attachment.cgi?id=206671. (but don't worry about applying patches. Also see https://wiki.archlinux.org/index.php/DSDT for a quicker way to load custom DSDTs without recompiling)
This should result in the intel-lpss driver attaching itself to the SPI controller, and exposing the APP000D device.
For this to work with the 2015 model, simply make sure that none of the intel-lpss kernel modules are installed.
- Basic Typing
- FN keys
- Driver unloading (no more hanging)
- Basic touchpad functionality (even right click, handled by libinput) (except for the 2015 12" Macbook)
- MT touchpad functionality (two finger scroll, probably others) (except for the 2015 12" Macbook)
- Interrupts!
- Suspend / resume
- Key rollover (properly)
- Wakeup on keypress / touchpad
- Occasionally, the SPI device can get itself into a state where it causes an interrupt storm. There should be a way of resetting it, or better yet avoiding this state altogether.
- You shouldn't have to modify your DSDT to get it running.
- For some reason, doing operations at 8MHz (the speed that the slave device should run at) fail. 400kHz works, but this should be investigated.
Interrupts are now working! This means that the driver is no longer polled, and should no longer be a massive battery drain. For more information on how the driver receives interrupts, see the discussion here
The touchpad protocol is the same as the bcm5974 driver. Perhaps there is a nice way of utilizing it? For now, bits of code have just been copy and pasted.