[alsa-devel] Volume issues: Logitech S-150 USB Digital Speaker / "usb_audio: Warning! Unlikely big volume range"

[Daniel Mack]

On Thu, Dec 12, 2013 at 02:35:29AM +0100, Linus Lüssing wrote:
> I'm currently trying to use a Logitech S-150 USB Digital Speaker.
> Unfortunately, the volume range is way off, i.e. only 1% and 2%
> settings in the alsamixer are actually usable for general
> playback.
> 
> dmesg:
> -----
> [ 9850.768093] usb 1-1: new full-speed USB device number 2 using uhci_hcd
> [ 9850.948103] usb 1-1: New USB device found, idVendor=1130, idProduct=1620
> [ 9850.948123] usb 1-1: New USB device strings: Mfr=0, Product=2, SerialNumber=0
> [ 9850.948138] usb 1-1: Product: USB  AUDIO
> [ 9852.353857] hidraw: raw HID events driver (C) Jiri Kosina
> [ 9852.397038] usb_audio: Warning! Unlikely big volume range (=17152), cval->res is probably wrong.

You're facing a firmware bug, most probably just an endianess issue
(17152 = 0x4300). You can add a quirk for this device in order to fix
it up. Have a look at volume_control_quirks() in sound/usb/mixer.c if
you want, or tell me the name of the affected volume control.

> [ 9852.397054] usb_audio: [2] FU [PCM Playback Volume] ch = 2, val = 0/17152/1<6>[ 9852.399123] usbcore: registered new interface driver snd-usb-audio
> [ 9852.412386] usbcore: registered new interface driver usbhid
> [ 9852.412400] usbhid: USB HID core driver
> [ 9852.562358] input: USB  AUDIO   as /devices/pci0000:00/0000:00:1d.0/usb1/1-1/1-1:1.2/input/input12
> [ 9852.563157] hid-generic 0003:1130:1620.0001: input,hidraw0: USB HID v1.10 Device [USB  AUDIO  ] on usb-0000:00:1d.0-1/input2
> -----
> 
> lsusb -d 1130:1620 (for lsusb -vvv, see attachment)
> -----
> Bus 001 Device 002: ID 1130:1620 Tenx Technology, Inc.
> -----
> 
> The detected vendor does not seem to match, so all in all
> looks like a kernel bug?

No, lsusb just shows you the name of the company that registered the USB
vendor ID, 0x1130 in this case. Logitech seems to have licensed a design
from another company here.


Daniel