V4l2 :: Debugging an issue with cx8800 card.

"B. Bogart" <ben@xxxxxxxxx> · Thu, 04 Sep 2008 15:14:32 -0700

Hello all,

This issue has been lagging for years and I wanted to get some expert
advice on debugging it. It seems I'm the only one with a cx8800 card
that is having problems so I hope to take the challenge up and propose a
solution to the maintainer.

So the software I'm using is GEM. It has v4l2 support, and works fine
with my bt848 card. Problem is I can't get things working properly with
my cx8800 cards.

First HW info:

lspci reports my tuner as:

00:0d.0 Multimedia video controller: Conexant CX23880/1/2/3 PCI Video
and Audio Decoder (rev 05)

The card is branded as a Leadtek Winfast 2000XP Expert.

I'm sure the problem is with the v4l2 implementation in Gem as running
the following command gives me perfect video on this card at 640x480:

mplayer tv:// -tv driver=v4l2:device=/dev/video0:input=1:norm=NTSC-M

(the output follows this message).

So the card is capable of 640x480.

If I run Gem on this card as 320x240 all works fine. (pictured in
attachment 320x240.png)

As soon as I change the resolution to 640x480 I get the following errors
repeated:

VIDIOCMCAPTURE1: Invalid argument
VIDIOCMCAPTURE2: Invalid argument

And the image appears as in attachment 640x480.png

What should my steps for debugging be?

Is there dead-simple v4l2 example source (including output so I can
confirm its working) I can test with and compare with Gem sources?

Any advice appreciated.

B. Bogart

--
Here is the mplayer output:

MPlayer dev-SVN-r26940
CPU: AMD Athlon(tm) 64 Processor 3200+ (Family: 15, Model: 47, Stepping: 0)
CPUflags:  MMX: 1 MMX2: 1 3DNow: 1 3DNow2: 1 SSE: 1 SSE2: 1
Compiled with runtime CPU detection.
Can't open joystick device /dev/input/js0: No such file or directory
Can't init input joystick
mplayer: could not connect to socket
mplayer: No such file or directory
Failed to open LIRC support. You will not be able to use your remote
control.

Playing tv://.
TV file format detected.
Selected driver: v4l2
 name: Video 4 Linux 2 input
 author: Martin Olschewski <olschewski@xxxxxxxxxxxxxxxx>
 comment: first try, more to come ;-)
Selected device: Leadtek Winfast 2000XP Expert
 Tuner cap:
 Tuner rxs:
 Capabilites:  video capture  VBI capture device  tuner  read/write
streaming
 supported norms: 0 = PAL-BG; 1 = PAL-DK; 2 = PAL-I; 3 = PAL-M; 4 =
PAL-N; 5 = PAL-Nc; 6 = PAL-60; 7 = NTSC-M; 8 = NTSC-M-JP; 9 = NTSC-443;
10 = SECAM-DK; 11 = SECAM-L;
 inputs: 0 = Television; 1 = Composite1; 2 = S-Video;
 Current input: 1
 Current format: BGR24
v4l2: current audio mode is : MONO
v4l2: ioctl set format failed: Invalid argument
v4l2: ioctl set format failed: Invalid argument
open: No such file or directory
[MGA] Couldn't open: /dev/mga_vid
open: No such file or directory
[MGA] Couldn't open: /dev/mga_vid
[VO_TDFXFB] Can't open /dev/fb0: No such file or directory.
s3fb: can't open /dev/fb0: No such file or directory
==========================================================================
Opening video decoder: [raw] RAW Uncompressed Video
VDec: vo config request - 640 x 480 (preferred colorspace: Packed UYVY)
VDec: using Packed UYVY as output csp (no 0)
Movie-Aspect is undefined - no prescaling applied.
VO: [xv] 640x480 => 640x480 Packed UYVY
Selected video codec: [rawuyvy] vfm: raw (RAW UYVY)
==========================================================================
Audio: no sound
Starting playback...
v4l2: 40 frames successfully processed, -39 frames dropped.

Exiting... (Quit)