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Linux内核源代码 为压缩文件 是<<Linux内核>>一书中的源代码

IMPORTANT:  Don't send me mails with images attached unless I ask you
to do so.  Mails with images attached will go to /dev/null unseen.


Release notes for bttv-0.7.x
============================

This version is based on Ralphs 0.6.4 release.  There are alot of
changes.  Bugfixes, merged patches from other people, merged fixes
from the kernel version, port to the new i2c stack, removed support
for 2.0.x, code cleanups, ...

To compile this bttv version, you'll the new i2c stack.  Kernels
newer than 2.3.34 have this already included.  If you have a older
kernel, download it from:
	http://www2.lm-sensors.nu/~lm78/download.html

You'll need at least these i2c config options for bttv:
CONFIG_I2C=m
CONFIG_I2C_ALGOBIT=m

The latest bttv version is available here:
	http://www.strusel007.de/linux/bttv/

You'll find Ralphs original (mostly outdated) documentation in the
ralphs-doc subdirectory.


Compile bttv
------------

If you are compiling the kernel version, just say 'm' if you are asked
for bttv.  I /strongly/ recommend to compile bttv as module, because
there are some insmod options for configuring the driver.  Starting
with 0.7.49 the most important ones are available as kernel args too.

If you downloaded the separate bttv bundle:  You need configured kernel
sources to compile the bttv driver.  The driver uses some Makefile
magic to compile the modules with your kernel's configuration
(wrt. module-versions, SMP, ...).  If you already have compiled the
kernel at least once, you probably don't have do worry about this.  If
not, go to /usr/src/linux and run at least "make config".  Even
better, compile your own kernel, you'll never become a real hacker
else ;-)
Note that you have to turn on video4linux support (CONFIG_VIDEO_DEV)
in the kernel to get the videodev.o module which is required by bttv.


Make bttv work with your card
-----------------------------

Of course you have to load the modules as very first thing.  The
separate bttv bundle comes with a script called "update".  I use this
one to load a new version while doing driver hacking.  You can use it
too, but check the module arguments first.  They work for my setup,
and probably do *not* for yours.  Another way is to setup your
/etc/modules.conf file and let kmod load the modules.  See also:

Modules.conf:	some sample entries for /etc/modules.conf
Insmod-options:	list of all insmod options available for bttv and
		the helper modules.
MAKEDEV:	a script to create the special files for v4l
CARDLIST:	List of all supported cards

Loading just the bttv modules isn't enouth for most cards.  The
drivers for the i2c tuner/sound chips must also be loaded.  bttv tries
to load them automagically by calling request_module() now, but this
obviously works only with kmod enabled.

The most important insmod option for bttv is "card=n" to select the
correct card type.  If you get video but no sound you've very likely
specified the wrong (or no) card type.  A list of supported cards is
in CARDLIST.

If your card isn't listed in CARDLIST or if you have trouble making
audio work, you should read the Sound-FAQ.


Still doesn't work?
-------------------

I do NOT have a lab with 30+ different grabber boards and a
PAL/NTSC/SECAM test signal generator at home, so I often can't
reproduce your problems.  This makes debugging very difficult for me.
If you have some knowledge and spare time, please try to fix this
yourself (patches very welcome of course...)  You know: The linux
slogan is "Do it yourself".

There is a mailing list: [e-mail].  If you have
trouble with some specific TV card, try to ask there instead of
mailing me directly.  The chance that someone with the same card
listens there is much higher...

For problems with sound:  There are alot of different systems used
for TV sound all over the world.  And there are also different chips
which decode the audio signal.  Reports about sound problems ("stereo
does'nt work") are pretty useless unless you include some details
about your hardware and the TV sound scheme used in your country (or
at least the country you are living in).


Finally: If you mail some patches for bttv around the world (to
linux-kernel/Alan/Linus/...), please Cc: me.


Have fun with bttv,

  Gerd

--
Gerd Knorr <[e-mail]>