The same problem on MacBook Air 2014 in the transition to the standby mode. After that set the brightness below 90% is not possible, the screen goes off completely. I think the problem in the module wl.
WARNING: CPU: 3 PID: 86 at drivers/gpu/drm/i915/intel_pm.c:6585 intel_display_power_put+0x15c/0x170 [i915]() [i915]
The same problem on MacBook Air 2014 in the transition to the standby mode. After that set the brightness below 90% is not possible, the screen goes off completely. I think the problem in the module wl. gpu/drm/ i915/intel_ pm.c:6585 intel_display_ power_put+ 0x15c/0x170 [i915]() [i915]
WARNING: CPU: 3 PID: 86 at drivers/