@RehabMan - I've recently upgraded my T440s to Sierra and I have it mostly working. I was able to apply this new brightness patch to get brightness working.
However, my key mappings (which I found from a guide on this site) are no longer correct. I was able to follow the ACPI-Keyboard guide to figure out which keys are mapping to which method in my EC device using the intercept method:
Mute: _Q43
Microphone Mute: _Q6A
Brightness Down: _Q15
Brightness Up: _Q14
Projector?: _Q16
Wifi Switch: _Q64
Settings: _Q66
Search: _Q67
View Programs: _Q68
View ALL Programs: _Q69
But where I'm confused is learning how to know what to put in these methods. Am I supposed to keep the RMKB device in my DSDT and then play around with the values in the ACPIKeyboard.cpp to invoke brightness? The older patches I found from Yosemite (
https://www.tonymacx86.com/threads/lenovo-t440s-working-fn-keys.158288/) are calling the KBD device directly.
Some guidance would be helpful!