Dne 10. 03. 23 v 14:43 Pavel Hofman napsal(a):
Hi,
Speaker-webcam eMeet C980 Pro does not play, outputs only silent noise.
The digital volume seems to be down.
dmesg:
[22406.805176] input: HD Webcam eMeet C980 Pro: HD We as
/devices/pci0000:00/0000:00:01.2/0000:02:00.0/usb1/1-7/1-7.1/1-7.1:1.0/input/input27
[22406.829048] usb 1-7.1: current rate 16000 is different from the
runtime rate 48000
[22406.933044] usb 1-7.1: Warning! Unlikely big volume range (=10240),
cval->res is probably wrong.
[22406.933048] usb 1-7.1: [5] FU [PCM Playback Volume] ch = 1, val =
-7168/3072/1
[22407.001043] usb 1-7.1: Warning! Unlikely big volume range (=3072),
cval->res is probably wrong.
[22407.001047] usb 1-7.1: [6] FU [Headset Capture Volume] ch = 1, val =
-1536/1536/1
Maybe it's a problem with endianness, like e.g. reported in
https://www.mail-archive.com/linux-kernel@xxxxxxxxxxxxxxx/msg2181737.html
All the large numbers are divisible by 256.
But honestly I do not know what the fix should be - converting the
min/max (min >>=8) or the resolution (res >>=8)?
What difference do the two methods make?
What effect does rewriting the cval min/max/res values actually have,
with regards to the reading from the device (get) and writing to the
device (put) methods?
Thanks a lot for any hint.
Best regards,
Pavel.
amixer contents:
.....
numid=3,iface=MIXER,name='PCM Playback Switch'
; type=BOOLEAN,access=rw------,values=1
: values=on
numid=4,iface=MIXER,name='PCM Playback Volume'
; type=INTEGER,access=rw---R--,values=1,min=0,max=10240,step=0
: values=10240
| dBminmax-min=-28.00dB,max=12.00dB
numid=5,iface=MIXER,name='Headset Capture Switch'
; type=BOOLEAN,access=rw------,values=1
: values=on
numid=6,iface=MIXER,name='Headset Capture Volume'
; type=INTEGER,access=rw---R--,values=1,min=0,max=3072,step=0
: values=3072
| dBminmax-min=-6.00dB,max=6.00dB
.....
