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dimich

Member

From: Kharkiv, Ukraine

Registered: 2009-11-03

Posts: 414

Dell Latitude 5400: Mic Mute key stopped working in 6.15

I noticed that Mic Mute key (Fn+F4) stopped to work.
It is still working fine with linux-lts, so I bisected kernel versions and found that it's broken in v6.15.1-arch1, i.e. 6.14.10.arch1-1: good, 6.15.1.arch1-1: bad.

In working version (before 6.15.1) `libinput debug-events` produces following output:

-event8   KEYBOARD_KEY                 +21.508s KEY_MICMUTE (248) pressed
 event8   KEYBOARD_KEY                 +21.508s KEY_MICMUTE (248) released

and `xev`, first press:

MappingNotify event, serial 30, synthetic NO, window 0x0,
    request MappingKeyboard, first_keycode 8, count 248

KeymapNotify event, serial 31, synthetic NO, window 0x0,
    keys:  1   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0   
           0   0   0   0   0   0   0   0   64  0   0   0   0   0   0   0   

KeyRelease event, serial 31, synthetic NO, window 0x1a00001,
    root 0x4db, subw 0x0, time 517010, (75,134), root:(76,156),
    state 0x0, keycode 198 (keysym 0x1008ffb2, XF86AudioMicMute), same_screen YES,
    XLookupString gives 0 bytes: 
    XFilterEvent returns: False

next press:

KeymapNotify event, serial 29, synthetic NO, window 0x0,
    keys:  219 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   

KeymapNotify event, serial 29, synthetic NO, window 0x0,
    keys:  219 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   

(Wierd behavior with `xev` but XF86AudioMicMute is handled normally by fluxbox key bindings).

In non-working versions (6.15.1 and later) `xev` and `libinput debug-events` print no messages when the key is pressed.

UPD: neighbour keys (volume mute / down / up, keyboard backlight, screen backlight etc) still are working fine.

I didn't found any relevant changes in drivers/platform/x86/dell/ between v6.14.10 and v6.15.1.
So I'm not sure where to file a bug report.

Last edited by dimich (2025-06-17 17:43:54)

dimich

Member

From: Kharkiv, Ukraine

Registered: 2009-11-03

Posts: 414

Re: Dell Latitude 5400: Mic Mute key stopped working in 6.15

Upstream bug report: https://bugzilla.kernel.org/show_bug.cgi?id=220246