[mythtv-users] Some analog channels are bad in ivtv but OK on the analog TV

Sathish Vasudevaiah holla.net at gmail.com
Tue Sep 6 01:00:21 UTC 2011


Hi,

(I had earlier posted this on ivtv-users list, I repost here for
larger audience, hope it is not ter
Lately my PVR350 based mythtv setup has one major issue.
In this setup analog cable signal is fed both to the pvr350
card and the TV using a splitter.

Now the problem is there are some channels which look
 good on TV but the same channel look very grainy and
blurry in mythtv. But there are also some channels which
are equally good on both TV and mythtv.

Here are few things done but no breakthrough.

- swapped the TV and the  PVR inputs, but this made no difference

- Using v4l2-ctl tuned a channel from 885.25 MHz to 62.50 MHz
in steps of 1 MHz and observed the ivtv output. I was looking for
a pattern in the blurry channels frequency, but found none.

- checked the ivtv decoder output (/dev/video0) directly, Same problem
 existed.

- changed the recording bitrates iin mythtv recording profiles for LiveTV

- For one grainy/blurry channel, fine tuned on either side of the frequency
using v4l2-ctl. Again no difference.

Can you please give some more ideas for debugging this ?

thanks
holla


Some system info
------------------------
kernel: 2.6.39.4 running Intel Atom based D510mo board

ivtv-related modules loaded:

ivtvfb                 12085  4
ivtv                  139106  1 ivtvfb
cx2341x                17783  1 ivtv
i2c_algo_bit            4857  1 ivtv
tveeprom               11113  1 ivtv
msp3400                25815  1
saa7127                 8167  1
saa7115                13581  1
tuner                  17420  1
tuner_simple           13140  1
tuner_types            14698  1 tuner_simple
v4l2_common             6913  6 ivtv,cx2341x,msp3400,saa7127,saa7115,tuner
videodev               79083  7
ivtv,cx2341x,msp3400,saa7127,saa7115,tuner,v4l2_common

syslog (the recursive lock warning does not seem to have any impact)

[   69.220797] Linux video capture interface: v2.00
[   69.264828] i2c-core: driver [tuner] using legacy suspend method
[   69.264839] i2c-core: driver [tuner] using legacy resume method
[   69.297763] i2c-core: driver [msp3400] using legacy suspend method
[   69.297773] i2c-core: driver [msp3400] using legacy resume method
[   69.348542] ivtv: Start initialization, version 1.4.2
[   69.348721] ivtv0: Initializing card 0
[   69.348731] ivtv0: Autodetected Hauppauge card (cx23415 based)
[   69.350466] ACPI: PCI Interrupt Link [LNKF] enabled at IRQ 11
[   69.350481] ivtv 0000:05:00.0: PCI INT A -> Link[LNKF] -> GSI 11
(level, low) -> IRQ 11
[   69.422441] tveeprom 0-0050: Hauppauge model 48134, rev J321, serial# 2764033
[   69.422452] tveeprom 0-0050: tuner model is Philips FM1216 (idx 21, type 5)
[   69.422460] tveeprom 0-0050: TV standards PAL(B/G) (eeprom 0x04)
[   69.422466] tveeprom 0-0050: audio processor is MSP4418 (idx 25)
[   69.422473] tveeprom 0-0050: decoder processor is SAA7115 (idx 19)
[   69.422479] tveeprom 0-0050: has radio, has IR receiver, has no IR
transmitter
[   69.422486] ivtv0: Autodetected Hauppauge WinTV PVR-350
[   69.455442] saa7115 0-0021: saa7115 found (1f7115d0e100000) @ 0x42
(ivtv i2c driver #0)
[   69.591207]
[   69.591210] =============================================
[   69.591291] [ INFO: possible recursive locking detected ]
[   69.591340] 2.6.39.4 #1
[   69.591375] ---------------------------------------------
[   69.591441] modprobe/226 is trying to acquire lock:
[   69.591505]  (&hdl->lock){+.+.+.}, at: [<f81a8202>]
handler_new_ref+0xa2/0x1d0 [videodev]
[   69.591683]
[   69.591685] but task is already holding lock:
[   69.591790]  (&hdl->lock){+.+.+.}, at: [<f81a8919>]
v4l2_ctrl_add_handler+0x59/0xc0 [videodev]
[   69.591965]
[   69.591967] other info that might help us debug this:
[   69.592009] 3 locks held by modprobe/226:
[   69.592009]  #0:  (&__lockdep_no_validate__){+.+.+.}, at:
[<c042d350>] __driver_attach+0x50/0x90
[   69.592009]  #1:  (&__lockdep_no_validate__){+.+.+.}, at:
[<c042d35c>] __driver_attach+0x5c/0x90
[   69.592009]  #2:  (&hdl->lock){+.+.+.}, at: [<f81a8919>]
v4l2_ctrl_add_handler+0x59/0xc0 [videodev]
[   69.592009]
[   69.592009] stack backtrace:
[   69.592009] Pid: 226, comm: modprobe Not tainted 2.6.39.4 #1
[   69.592009] Call Trace:
[   69.592009]  [<c0603062>] ? printk+0x19/0x1f
[   69.592009]  [<c01743e5>] __lock_acquire+0x11b5/0x1860
[   69.592009]  [<c0173030>] ? mark_lock+0x190/0x390
[   69.592009]  [<c0174fcd>] lock_acquire+0x7d/0x100
[   69.592009]  [<f81a8202>] ? handler_new_ref+0xa2/0x1d0 [videodev]
[   69.592009]  [<c01394eb>] ? get_parent_ip+0xb/0x40
[   69.592009]  [<f81a8202>] ? handler_new_ref+0xa2/0x1d0 [videodev]
[   69.592009]  [<c060484c>] mutex_lock_nested+0x5c/0x330
[   69.592009]  [<f81a8202>] ? handler_new_ref+0xa2/0x1d0 [videodev]
[   69.592009]  [<f81a81db>] ? handler_new_ref+0x7b/0x1d0 [videodev]
[   69.592009]  [<f81a8202>] handler_new_ref+0xa2/0x1d0 [videodev]
[   69.592009]  [<f81a8919>] ? v4l2_ctrl_add_handler+0x59/0xc0 [videodev]
[   69.592009]  [<f81a8949>] v4l2_ctrl_add_handler+0x89/0xc0 [videodev]
[   69.592009]  [<f81a5019>] v4l2_device_register_subdev+0xd9/0x1b0 [videodev]
[   69.592009]  [<c01394eb>] ? get_parent_ip+0xb/0x40
[   69.592009]  [<f80194d3>] v4l2_i2c_new_subdev_board+0x103/0x1a0 [v4l2_common]
[   69.592009]  [<c0397bea>] ? strlcpy+0x3a/0x50
[   69.592009]  [<f80195bf>] v4l2_i2c_new_subdev+0x4f/0x60 [v4l2_common]
[   69.592009]  [<f873babc>] ivtv_i2c_register+0x27c/0x3c0 [ivtv]
[   69.592009]  [<f874a9bb>] ivtv_probe+0x105f/0x15ee [ivtv]
[   69.592009]  [<c01394eb>] ? get_parent_ip+0xb/0x40
[   69.592009]  [<c0139593>] ? sub_preempt_count+0x73/0xb0
[   69.592009]  [<c0606c89>] ? _raw_spin_unlock_irqrestore+0x39/0x70
[   69.592009]  [<c0430f84>] ? pm_runtime_enable+0x44/0x70
[   69.592009]  [<c03ade13>] local_pci_probe+0x43/0xb0
[   69.592009]  [<c03ae0f0>] pci_device_probe+0x60/0x80
[   69.592009]  [<c042d1ea>] driver_probe_device+0x7a/0x190
[   69.592009]  [<c042d389>] __driver_attach+0x89/0x90
[   69.592009]  [<c042d300>] ? driver_probe_device+0x190/0x190
[   69.592009]  [<c042c1b2>] bus_for_each_dev+0x42/0x70
[   69.592009]  [<c042ceda>] driver_attach+0x1a/0x20
[   69.592009]  [<c042d300>] ? driver_probe_device+0x190/0x190
[   69.592009]  [<c042cb17>] bus_add_driver+0xb7/0x280
[   69.592009]  [<c03ae570>] ? store_new_id+0x100/0x100
[   69.592009]  [<c042d686>] driver_register+0x66/0x110
[   69.592009]  [<c03a05d3>] ? __raw_spin_lock_init+0x33/0x60
[   69.592009]  [<c03ae335>] __pci_register_driver+0x55/0xc0
[   69.592009]  [<f875a073>] module_start+0x73/0x9a [ivtv]
[   69.592009]  [<c0101101>] do_one_initcall+0x31/0x170
[   69.592009]  [<f875a000>] ? 0xf8759fff
[   69.592009]  [<c017e996>] sys_init_module+0x116/0x19c0
[   69.592009]  [<c0607790>] sysenter_do_call+0x12/0x36
[   69.607742] saa7127 0-0044: saa7127 found @ 0x88 (ivtv i2c driver #0)
[   69.661646] msp3400 0-0040: MSP4418G-A2 found @ 0x80 (ivtv i2c driver #0)
[   69.661725] msp3400 0-0040: msp3400 supports nicam and radio, mode
is autodetect and autoselect
[   69.685194] tuner 0-0061: Tuner -1 found with type(s) Radio TV.
[   69.687530] tuner-simple 0-0061: creating new instance
[   69.687624] tuner-simple 0-0061: type set to 5 (Philips PAL_BG
(FI1216 and compatibles))
[   69.703132] ivtv0: Registered device video0 for encoder MPG (16384 kB)
[   69.703482] ivtv0: Registered device video32 for encoder YUV (2048 kB)
[   69.703735] ivtv0: Registered device vbi0 for encoder VBI (8192 kB)
[   69.703979] ivtv0: Registered device video24 for encoder PCM (320 kB)
[   69.705327] ivtv0: Registered device radio0 for encoder radio
[   69.705917] ivtv0: Registered device video16 for decoder MPG (1024 kB)
[   69.706200] ivtv0: Registered device vbi8 for decoder VBI (64 kB)
[   69.707902] ivtv0: Registered device vbi16 for decoder VOUT
[   69.710185] ivtv0: Registered device video48 for decoder YUV (1024 kB)
[   69.710264] ivtv0: Initialized card: Hauppauge WinTV PVR-350
[   69.710395] ivtv: End initialization
[   70.383320] ivtv0: Loaded v4l-cx2341x-enc.fw firmware (376836 bytes)
[   70.412114] ivtv0: Loaded v4l-cx2341x-dec.fw firmware (262144 bytes)
[   70.612502] ivtv0: Encoder revision: 0x02060039
[   70.612746] ivtv0: Decoder revision: 0x02020023
[   70.692074] ivtv0: Loaded v4l-cx2341x-init.mpg firmware (155648 bytes)
[   70.873745] ivtvfb0: Framebuffer at 0xe1510000, mapped to
0xf9510000, size 1665k
[   71.169245] Console: switching to colour frame buffer device 90x36
[   71.280594] ivtvfb0: Framebuffer registered on ivtv0


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