[Solved] Brightness up and down keys emit no keypress

My brightness up and down keys don’t emit a keypress. All of the other media keys do.

Here is what’s actually emitted.

FocusOut event, serial 44, synthetic NO, window 0x1600001,
    mode NotifyGrab, detail NotifyAncestor

FocusOut event, serial 44, synthetic NO, window 0x1600001,
    mode NotifyUngrab, detail NotifyPointer

FocusIn event, serial 44, synthetic NO, window 0x1600001,
    mode NotifyUngrab, detail NotifyAncestor

KeymapNotify event, serial 44, synthetic NO, window 0x0,
    keys:  2   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0
           0   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0

I’m trying to find a way to bind this to backlightctl in my i3 config but there’s just nothing there.

So, the brightness keys and the RF kill key (“airplane mode”) come in on separate input devices. On my machine, they are enumerated as /dev/input/event6 (“Wireless Radio Control”) and /dev/input/event7 (Consumer Control).

Perhaps that will help you find a lead?

# evtest /dev/input/event7
Input driver version is 1.0.1
Input device ID: bus 0x18 vendor 0x32ac product 0x6 version 0x100
Input device name: "FRMW0001:00 32AC:0006 Consumer Control"
...
Testing ... (interrupt to exit)
Event: time 1655408778.181509, type 4 (EV_MSC), code 4 (MSC_SCAN), value c006f
Event: time 1655408778.181509, type 1 (EV_KEY), code 225 (KEY_BRIGHTNESSUP), value 1
Event: time 1655408778.181509, -------------- SYN_REPORT ------------
Event: time 1655408778.209978, type 4 (EV_MSC), code 4 (MSC_SCAN), value c006f
Event: time 1655408778.209978, type 1 (EV_KEY), code 225 (KEY_BRIGHTNESSUP), value 0
Event: time 1655408778.209978, -------------- SYN_REPORT ------------

So my RFKill key did emit a XF86RFKill on xev.

evtest returns some info but does not catch any of the events

Input driver version is 1.0.1
Input device ID: bus 0x19 vendor 0x0 product 0x6 version 0x0
Input device name: "Video Bus"
Supported events:
  Event type 0 (EV_SYN)
  Event type 1 (EV_KEY)
    Event code 224 (KEY_BRIGHTNESSDOWN)
    Event code 225 (KEY_BRIGHTNESSUP)
    Event code 227 (KEY_SWITCHVIDEOMODE)
    Event code 241 (KEY_VIDEO_NEXT)
    Event code 242 (KEY_VIDEO_PREV)
    Event code 243 (KEY_BRIGHTNESS_CYCLE)
    Event code 244 (KEY_BRIGHTNESS_ZERO)
    Event code 245 (KEY_DISPLAY_OFF)
Properties:
Testing ... (interrupt to exit)

Okay it looks like an XF86MonBrightnessUp/Down is emitted, although xev doesn’t see it. My brightness command isn’t going through for some reason. If that doesn’t work I’ll open a new issue