[alsa-devel] Lost dB volumes on USB headset between 2.6.38 and 3.0

[Colin Guthrie]

'Twas brillig, and Clemens Ladisch at 09/08/11 12:39 did gyre and gimble:
> David Henningsson wrote:
>> Hmm, I and Colin Guthrie have found a regression between kernels 2.6.38
>> and 3.0.
>>
>> When running "amixer -D hw:handset" for this device under 2.6.38, the
>> attached file is returned. Under 3.0, the dB information is missing.
>> This can't be intentional, can it?
> 
> There are patches that might have introduced bugs, but these two patches
> do remove dB information intentionally:
> 
> ALSA: usb-audio - Don't expose broken dB ranges:
> http://git.alsa-project.org/?p=alsa-kernel.git;a=commitdiff;h=59bb7f0eebe6
> ALSA: usb-audio - Add volume range check and warn if it too big:
> http://git.alsa-project.org/?p=alsa-kernel.git;a=commitdiff;h=80acefff3bc7
> 
> Are there any messages in the system log when loading the driver?
> What are the controls' dB ranges (see "amixer contents")?

Interesting thanks fpr the hints.

I get this when plugging in the device David mentioned previously.


usb 3-1: USB disconnect, device number 2
usbcore: deregistering interface driver snd-usb-audio
usb 2-1: new full speed USB device number 7 using uhci_hcd
usb 2-1: New USB device found, idVendor=1885, idProduct=0501
usb 2-1: New USB device strings: Mfr=2, Product=1, SerialNumber=0
usb 2-1: Product: BT Agile handset
usb 2-1: Manufacturer: Ascalade
input: Ascalade BT Agile handset as
/devices/pci0000:00/0000:00:1d.1/usb2/2-1/2-1:1.3/input/input14
generic-usb 0003:1885:0501.0006: input,hidraw0: USB HID v1.00 Device
[Ascalade BT Agile handset] on usb-0000:00:1d.1-1/input3
13:0: cannot get min/max values for control 2 (id 13)
14:0: cannot get min/max values for control 2 (id 14)
9:0: cannot get min/max values for control 2 (id 9)
10:0: cannot get min/max values for control 2 (id 10)
11:0: cannot get min/max values for control 2 (id 11)
9:0: cannot get min/max values for control 2 (id 9)
14:0: cannot get min/max values for control 2 (id 14)
11:0: cannot get min/max values for control 2 (id 11)
13:0: cannot get min/max values for control 2 (id 13)
10:0: cannot get min/max values for control 2 (id 10)
9:0: cannot get min/max values for control 2 (id 9)
usbcore: registered new interface driver snd-usb-audio


-- 

Colin Guthrie
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http://colin.guthr.ie/

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