sysfs_light handles every case sanely already, no need to be cute ;).
This prevents always setting the warmth when setting the FL on NL
devices with a mixer, because, besides being useless, it's also slow
(lua does mmap'ed io, so every handle requires an fstat + mmap).
It was subtly affecting the fluidity of the toggle ramp, and much less
subtly wreaking havoc on #5373 ;).
KA1 owners might want to investigate keeping the fds around one way or
another, like we do for the fl ioctl, to alleviate the overhead of doing
that for not one but three or four fds...
I won't be doing that, since I lack the hardware to test it, and FL+NL
stuff is pain.
* Do the same on Cervantes
* Bump base to pickup related ioctl tweaks
Companion PR to https://github.com/koreader/koreader-base/pull/884
* Basically flags devices known to be stable when using PxP inversion.
* Plus, random fix for #4870 ;).
* A few FrontLight tweaks & cleanups on Kobo:
* Moved the Kobo-specific startup status insanity to Kobo-specific init
* Made turnOff/turnOn frontlight do a smooth ramp down/up
* On Kobo, use turnOff/turnOn for suspend/resume, to get that smooth toggle
* On Kobo, for NaturalLight w/ a mixer, only set warmth for setWarmth, and only set Brightness for setBrightness, otherwise, it tried to set both with not in-sync values, which made the FL widget jittery.
* Enforce a known rotation on startup, to make sure we handle touch input coordinates properly.
* Proper FrontLight warmth support (thanks to @cairnsh & @pazos in #4291)!
* Fix the PageTurn buttons mapping to match Nickel's defaults
* Properly remap PageTurn buttons depending on the current rotation.
* Actually enable the Mk.7 screen refresh codepath on *all* Mk.7 devices (I'd messed up the device check...).
* Full accelerometer handling (includes a touch of refactoring regarding orientation handling in general).
* Fix insidiously broken USBMS behavior in Nickel after we exit on FW >4.8.
Fix#4291Fix#3002
