Comment # 11 on bug 1192181 from Andreas Nordal

I'm happy to report that the brightness keys are now working!
Without me doing anything beyond keeping my system up to date.

* The kernel is upgraded since last time: Linux 5.14.6-1-default ��������� Linux
5.16.0-1-default
* I didn't need to upgrade the BIOS (thank goodness, because HP doesn't make it
easy): Still HP R70 Ver. 01.04.05

The 3 previously indistinguishable keys are now distinguishable in evtest:

Brightness down key:
Event: time 1643270483.474037, type 4 (EV_MSC), code 4 (MSC_SCAN), value 92
Event: time 1643270483.474037, type 1 (EV_KEY), code 224 (KEY_BRIGHTNESSDOWN),
value 1
Event: time 1643270483.474037, -------------- SYN_REPORT ------------
Event: time 1643270483.526190, type 4 (EV_MSC), code 4 (MSC_SCAN), value 92
Event: time 1643270483.526190, type 1 (EV_KEY), code 224 (KEY_BRIGHTNESSDOWN),
value 0
Event: time 1643270483.526190, -------------- SYN_REPORT ------------

Brightness up key:
Event: time 1643270486.207376, type 4 (EV_MSC), code 4 (MSC_SCAN), value 97
Event: time 1643270486.207376, type 1 (EV_KEY), code 225 (KEY_BRIGHTNESSUP),
value 1
Event: time 1643270486.207376, -------------- SYN_REPORT ------------
Event: time 1643270486.268492, type 4 (EV_MSC), code 4 (MSC_SCAN), value 97
Event: time 1643270486.268492, type 1 (EV_KEY), code 225 (KEY_BRIGHTNESSUP),
value 0
Event: time 1643270486.268492, -------------- SYN_REPORT ------------

Mic mute key (identical for mute and unmute):
Event: time 1643271216.192007, type 4 (EV_MSC), code 4 (MSC_SCAN), value 81
Event: time 1643271216.192007, type 1 (EV_KEY), code 190 (KEY_F20), value 1
Event: time 1643271216.192007, -------------- SYN_REPORT ------------
Event: time 1643271216.230921, type 4 (EV_MSC), code 4 (MSC_SCAN), value 81
Event: time 1643271216.230921, type 1 (EV_KEY), code 190 (KEY_F20), value 0
Event: time 1643271216.230921, -------------- SYN_REPORT ------------