Comment 238 for bug 1098216

(In reply to Aaron Lu from comment #109)
> Hi,
>
> Rafael has revised the patches and now the following two patches are
> available:
> https://patchwork.kernel.org/patch/2812951/ (expose OSI version)
> https://patchwork.kernel.org/patch/2827793/ (win8 video quirk)
>
> Please give it a test, thanks. Hopefully, this is the last update to this
> problem.

Ok, so I've tried those patches on top of 3.10.1 and it seems to work just fine for me. It seems that I have brightness keys working as soon as i915 is loaded (so even before X is even started, not to mention any desktop environment power management daemon).

In /sys/class/backlight there's only intel_backlight with:

grep -r . /sys/class/backlight/intel_backlight
/sys/class/backlight/intel_backlight/type:raw
/sys/class/backlight/intel_backlight/brightness:3219
/sys/class/backlight/intel_backlight/power/control:auto
/sys/class/backlight/intel_backlight/power/async:disabled
/sys/class/backlight/intel_backlight/power/runtime_enabled:disabled
/sys/class/backlight/intel_backlight/power/runtime_active_kids:0
/sys/class/backlight/intel_backlight/power/runtime_active_time:0
grep: /sys/class/backlight/intel_backlight/power/autosuspend_delay_ms: Input/output error
/sys/class/backlight/intel_backlight/power/runtime_status:unsupported
/sys/class/backlight/intel_backlight/power/runtime_usage:0
/sys/class/backlight/intel_backlight/power/runtime_suspended_time:0
/sys/class/backlight/intel_backlight/bl_power:0
/sys/class/backlight/intel_backlight/max_brightness:4438
/sys/class/backlight/intel_backlight/actual_brightness:3219

Although I now have warnings from thinkpad_acpi about unhandled key events:

Jul 16 13:54:36 balvenie kernel: [ 419.375753] thinkpad_acpi: unknown possible thermal alarm or keyboard event received
Jul 16 13:54:36 balvenie kernel: [ 419.375756] thinkpad_acpi: unhandled HKEY event 0x6050
Jul 16 13:54:36 balvenie kernel: [ 419.375758] thinkpad_acpi: please report the conditions when this event happened to <email address hidden>

each time I press one button. As far as I can tell they're harmless but Henrique would be better placed than me to assess that.