|
The tap-to-mute button of the HyperX QuadCast 2 (03f0:07b4) is handled
entirely in the device firmware. The firmware gates the audio internally
but never sends the Telephony "Phone Mute" usage (0x2f) that its own report
descriptor advertises, and it does not touch the UAC feature unit either.
Consequently neither an evdev key event nor an ALSA mixer change is ever
generated, and userspace has no way to learn that the microphone was muted:
desktops keep showing the microphone as live, and conferencing applications
keep displaying an unmuted microphone while transmitting silence.
The mute state is reported through a vendor-defined collection instead:
06 c0 ff Usage Page (Vendor-Defined 0xFFC0)
a1 01 Collection (Application)
06 c1 ff Usage Page (Vendor-Defined 0xFFC1)
85 77 Report ID (0x77)
09 f0 Usage (0xF0)
75 08 95 3f Report Size (8), Report Count (63)
81 02 Input (Data,Var,Abs)
Pressing the button emits a 64-byte report on that collection:
77 06 00 00 ... microphone unmuted
77 06 01 00 ... microphone muted
where byte 1 identifies the mute event and byte 2 carries the resulting
state. As the payload is an opaque vendor blob carrying no HID usages,
hid-input cannot map it and a hwdb entry cannot express it either.
Add a driver that decodes the report and emits KEY_MICMUTE, which makes the
button behave like any other microphone mute key.
Note that the device reports the resulting absolute state, whereas
KEY_MICMUTE is a momentary key that userspace acts on as a toggle, so the
driver emits one keypress per state change.
Tested on a HyperX QuadCast 2 (03f0:07b4).
Signed-off-by: Benjamin Blume <benjaminblume@posteo.de>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
|
