bttv module intialization takes much time on kernel-2.4.x

bttv module intialization takes much time on kernel-2.4.x

[Tetsuji Rai]

Title says it all.  I use bttv module.   When invoking "modprobe bttv" it 
takes several minutes to initialize.  When I used kernel-2.2.x it was very 
quick, but with kernel-2.4.x it takes a while.   But after that, it works 
fine.
   I don't know why.  Any solutions??  or am I doing anything wrong?
For your reference, I use BT878 based card, kernel-2.4.15-pre8 for now and 
dmesg gives these messages:
----snip----snip-----
i2c-core.o: i2c core module
i2c-algo-bit.o: i2c bit algorithm module
bttv: driver version 0.7.83 loaded
bttv: using 2 buffers with 2080k (4160k total) for capture
bttv: Host bridge is Intel Corp. 82815 815 Chipset Host Bridge and Memory 
Controller Hub
bttv: Bt8xx card found (0).
PCI: Found IRQ 5 for device 02:05.0
PCI: Sharing IRQ 5 with 02:05.1
bttv0: Bt878 (rev 17) at 02:05.0, irq: 5, latency: 32, memory: 0xe0000000
bttv0: using: BT878( *** UNKNOWN/GENERIC **) [card=0,autodetected]
i2c-core.o: adapter bt848 #0 registered as adapter 0.
bttv0: i2c: checking for MSP34xx @ 0x80... not found
bttv0: i2c: checking for TDA9875 @ 0xb0... not found
bttv0: i2c: checking for TDA7432 @ 0x8a... not found
i2c-core.o: driver i2c TV tuner driver registered.
------snip-----snip------
TIA

-- 
Tetsuji Rai (in Tokyo)
http://www.geocities.com/tetsuji_rai
Fax: +1-708-570-4868 (in the US)

Re: bttv module intialization takes much time on kernel-2.4.x

[Gerd Knorr]

Tetsuji Rai wrote:
>  Title says it all.  I use bttv module.   When invoking "modprobe bttv" it 
>  takes several minutes to initialize.  When I used kernel-2.2.x it was very 
>  quick, but with kernel-2.4.x it takes a while.   But after that, it works 
>  fine.
>     I don't know why.  Any solutions??

RTFM?

Documentation/video4linux/bttv/README says:

If bttv takes very long to load (happens sometimes with the cheap
cards which have no tuner), try adding this to your modules.conf:
        options i2c-algo-bit bit_test=1

HTH,

  Gerd

Re: bttv module intialization takes much time on kernel-2.4.x

[Adrian Cox]

Gerd Knorr wrote:


> RTFM?
> 
> Documentation/video4linux/bttv/README says:
> 
> If bttv takes very long to load (happens sometimes with the cheap
> cards which have no tuner), try adding this to your modules.conf:
>         options i2c-algo-bit bit_test=1


This is a nuisance on embedded systems which don't use modules, and 
which don't have tuners. I've ended up maintaining a local patch to 
force this on. It affects every user of i2c-algo-bit, but nothing else 
on this particular board suffers as a consequence.

What might be useful would be a config option to build bttv without 
tuners and i2c to reduce code size and sidestep this problem. Would you 
take a patch that did that?


-- 
Adrian Cox   http://www.humboldt.co.uk/