'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