Can not tune DSB-R100 USB radio via Video4Linux v1 after upgrading to Karmic

[James Henstridge]

After upgrading to Karmic (kernel 2.6.31-14-generic, amd64), I found that I could no longer tune my USB radio with the "fm" command (from the package fmtools). I was able to tune it using Rhythmbox's FM radio plugin.

Once the radio had been tuned, the "fm" tool was capable of turning it on and off.

The main difference between these two apps is that one uses the Video4Linux v1 API while the other uses the v2 API. Poking around with the v4l-info command confirmed that the tuner capability was only available via V4L2.

Given that the dsb-r100 module's V4L1 support is provided via the v4l1_compat module, I'd guess that the bug lies in that layer.

ProblemType: Bug
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/pcmC0D1p: james 2288 F...m pulseaudio
 /dev/snd/controlC0: james 2288 F.... pulseaudio
 /dev/snd/controlC1: james 2288 F.... pulseaudio
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
 Card hw:0 'V8237'/'VIA 8237 with ALC850 at 0xd800, irq 22'
   Mixer name : 'Realtek ALC850 rev 0'
   Components : 'AC97a:414c4790'
   Controls : 49
   Simple ctrls : 30
Card1.Amixer.info:
 Card hw:1 'Headset'/'Logitech Logitech USB Headset at usb-0000:00:10.2-1, full speed'
   Mixer name : 'USB Mixer'
   Components : 'USB046d:0a02'
   Controls : 6
   Simple ctrls : 2
Date: Thu Nov 5 16:01:29 2009
DistroRelease: Ubuntu 9.10
HibernationDevice: RESUME=UUID=b9bf1e33-a801-4da4-a864-4e89a83e7ae5
IwConfig:
 lo no wireless extensions.

 eth0 no wireless extensions.

 pan0 no wireless extensions.
MachineType: To Be Filled By O.E.M. To Be Filled By O.E.M.
Package: linux-image-2.6.31-14-generic 2.6.31-14.48
ProcCmdLine: BOOT_IMAGE=/vmlinuz-2.6.31-14-generic root=UUID=ae671e3f-d861-46c9-858e-d4972a7d0499 ro quiet splash
ProcEnviron:
 PATH=(custom, user)
 LANG=en_AU.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.31-14.48-generic
RelatedPackageVersions:
 linux-backports-modules-2.6.31-14-generic N/A
 linux-firmware 1.24
RfKill:
 0: hci0: Bluetooth
  Soft blocked: no
  Hard blocked: no
SourcePackage: linux
Uname: Linux 2.6.31-14-generic x86_64
WifiSyslog:
 Nov 5 14:36:06 nibbler dhclient: DHCPREQUEST of 192.168.0.2 on eth0 to 192.168.0.1 port 67
 Nov 5 14:36:06 nibbler dhclient: DHCPACK of 192.168.0.2 from 192.168.0.1
 Nov 5 14:36:06 nibbler dhclient: bound to 192.168.0.2 -- renewal in 102660 seconds.
WpaSupplicantLog:

dmi.bios.date: 10/06/2005
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 1015.002
dmi.board.name: A8V Deluxe
dmi.board.vendor: ASUSTeK Computer Inc.
dmi.board.version: Rev 1.xx
dmi.chassis.asset.tag: Asset-1234567890
dmi.chassis.type: 3
dmi.chassis.vendor: Chassis Manufacture
dmi.chassis.version: Chassis Version
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr1015.002:bd10/06/2005:svnToBeFilledByO.E.M.:pnToBeFilledByO.E.M.:pvrToBeFilledByO.E.M.:rvnASUSTeKComputerInc.:rnA8VDeluxe:rvrRev1.xx:cvnChassisManufacture:ct3:cvrChassisVersion:
dmi.product.name: To Be Filled By O.E.M.
dmi.product.version: To Be Filled By O.E.M.
dmi.sys.vendor: To Be Filled By O.E.M.

[James Henstridge (jamesh)]

Attached is the output of "v4l-info /dev/radio0". Notice that the tuner info shows up under "v4l2 device info", but an ioctl error is printed under "video4linux device info".

[James Henstridge (jamesh)]

I found bug 422822 that is looks similar to the problems I've seen but with different hardware. I added some instructions to that bug that would let the reporter verify whether he can tune his card with v4l2.

If that does fix his problem, then these bugs would be duplicates and it would support the theory that the bug lies in v4l1_compat.

[James Henstridge (jamesh)]

I haven't tested it, but this commit looks like the fix for the bug:

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=707ca1e30f087f9a6d144693dafc4b67880678c2

[James Henstridge (jamesh)]

I've just tried out the radio tuner under Lucid, and can tune it via the V4L 1 interface. So the bug only affects Karmic.

Fixing this in Karmic would require backporting the above referenced kernel patch.

[Brad Figg (brad-figg)]

This bug was filed against a series that is no longer supported and so is being marked as Won't Fix. If this issue still exists in a supported series, please file a new bug.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.