[linux-dvb] KWORLD 323U, kernel panic when trying to access ALSA interface

Devin Heitmueller dheitmueller at kernellabs.com
Mon Sep 28 17:56:28 CEST 2009


On Mon, Sep 28, 2009 at 11:50 AM, Marios Andreopoulos
<opensource at andmarios.com> wrote:
> Hello,
> I own a KWORLD 323U USB hybrid tv tuner.
>
> My problem is about the analog sound. When I am trying to access the alsa audio interface of this device I get kernel panics.
> I use commands like these in order to transfer audio from the tuner to my sound card:
> $ sox -r 48000 -c 2 -v 1 -t alsa hw:1 -t alsa hw:0
> $ arecord -D hw:1 | aplay -D hw:0 -
>
> When I use OSS I generally do not get kernel panics, although I have them on some occasions:
> $ sox -r 48000 -c 2 -v 1 -t ossdsp /dev/dsp1 -t ossdsp /dev/dsp
>
> A couple of times, after playing with OSS (changing sample rate or number of channels) I managed to use ALSA without a kernel panic but I didn't manage to find a workflow that will allow me to use ALSA every time.
>
> I have tried both the in kernel drivers (kernel version 2.6.31) and the latest drivers from the Hg tree as described in http://www.linuxtv.org/wiki/index.php/How_to_Obtain,_Build_and_Install_V4L-DVB_Device_Drivers
>
> I would appreciate any help as OSS gives me a terrible audio lag and ALSA -both times I managed it to work- seemed to not have any significant audio lag.
>
> In case there is anyone interested in this tuner I will add that I haven't managed to get DVB-T or the remote to work.
>
> My dmesg output in case it helps:
>
> usb 2-1.2: new high speed USB device using ehci_hcd and address 9
> usb 2-1.2: configuration #1 chosen from 1 choice
> em28xx: New device USB 2883 Device @ 480 Mbps (eb1a:e323, interface 0, class 0)
> em28xx #0: chip ID is em2882/em2883
> em28xx #0: i2c eeprom 00: 1a eb 67 95 1a eb 23 e3 d0 12 5c 00 6a 22 00 00
> em28xx #0: i2c eeprom 10: 00 00 04 57 4e 07 00 00 00 00 00 00 00 00 00 00
> em28xx #0: i2c eeprom 20: 46 00 01 00 f0 10 01 00 00 00 00 00 5b 1e 00 00
> em28xx #0: i2c eeprom 30: 00 00 20 40 20 80 02 20 10 01 00 00 00 00 00 00
> em28xx #0: i2c eeprom 40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> em28xx #0: i2c eeprom 50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> em28xx #0: i2c eeprom 60: 00 00 00 00 00 00 00 00 00 00 22 03 55 00 53 00
> em28xx #0: i2c eeprom 70: 42 00 20 00 32 00 38 00 38 00 33 00 20 00 44 00
> em28xx #0: i2c eeprom 80: 65 00 76 00 69 00 63 00 65 00 00 00 00 00 00 00
> em28xx #0: i2c eeprom 90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> em28xx #0: i2c eeprom a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> em28xx #0: i2c eeprom b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> em28xx #0: i2c eeprom c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> em28xx #0: i2c eeprom d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> em28xx #0: i2c eeprom e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> em28xx #0: i2c eeprom f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> em28xx #0: EEPROM ID= 0x9567eb1a, EEPROM hash = 0x0d913542
> em28xx #0: EEPROM info:
> em28xx #0:      AC97 audio (5 sample rates)
> em28xx #0:      500mA max power
> em28xx #0:      Table at 0x04, strings=0x226a, 0x0000, 0x0000
> em28xx #0: Identified as Kworld VS-DVB-T 323UR (card=54)
> em28xx #0:
>
> em28xx #0: The support for this board weren't valid yet.
> em28xx #0: Please send a report of having this working
> em28xx #0: not to V4L mailing list (and/or to other addresses)
>
> tvp5150 2-005c: chip found @ 0xb8 (em28xx #0)
> tuner 2-0061: chip found @ 0xc2 (em28xx #0)
> xc2028 2-0061: creating new instance
> xc2028 2-0061: type set to XCeive xc2028/xc3028 tuner
> usb 2-1.2: firmware: requesting xc3028-v27.fw
> xc2028 2-0061: Loading 80 firmware images from xc3028-v27.fw, type: xc2028 firmware, ver 2.7
> xc2028 2-0061: Loading firmware for type=BASE (1), id 0000000000000000.
> xc2028 2-0061: Loading firmware for type=(0), id 000000000000b700.
> SCODE (20000000), id 000000000000b700:
> xc2028 2-0061: Loading SCODE for type=MONO SCODE HAS_IF_4320 (60008000), id 0000000000008000.
> em28xx #0: Config register raw data: 0xd0
> em28xx #0: AC97 vendor ID = 0xffffffff
> em28xx #0: AC97 features = 0x6a90
> em28xx #0: Empia 202 AC97 audio processor detected
> tvp5150 2-005c: tvp5150am1 detected.
> em28xx #0: v4l2 driver version 0.1.2
> em28xx #0: V4L2 video device registered as /dev/video0
> em28xx #0: V4L2 VBI device registered as /dev/vbi0
> em28xx-audio.c: probing for em28x1 non standard usbaudio
> em28xx-audio.c: Copyright (C) 2006 Markus Rechberger
> tvp5150 2-005c: tvp5150am1 detected.
>
>
> Thanks in advance for any help,
> Marios Andreopoulos.
>
> _______________________________________________
> linux-dvb users mailing list
> For V4L/DVB development, please use instead linux-media at vger.kernel.org
> linux-dvb at linuxtv.org
> http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb
>

Hello Marios,

I started doing some debugging em28xx audio on the HVR-950 and hit
what is probably the same panic (which occurs as soon as you run the
arecord command).  I've got a stack dump and am actively debugging the
issue.

It seems that a regression has been recently introduced.

Devin

-- 
Devin J. Heitmueller - Kernel Labs
http://www.kernellabs.com



More information about the linux-dvb mailing list