android_kernel_xiaomi_sm8350/Documentation/video4linux/bttv/README

Release notes for bttv
======================

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

The latest bttv version is available from http://bytesex.org/bttv/


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

Just try "modprobe bttv" and see if that works.

If it doesn't bttv likely could not autodetect your card and needs some
insmod options.  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.bttv

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

For the WinTV/PVR you need one firmware file from the driver CD:
hcwamc.rbf.  The file is in the pvr45xxx.exe archive (self-extracting
zip file, unzip can unpack it).  Put it into the /etc/pvr directory or
use the firm_altera=<path> insmod option to point the driver to the
location of the file.

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


Autodetecting cards
-------------------

bttv uses the PCI Subsystem ID to autodetect the card type.  lspci lists
the Subsystem ID in the second line, looks like this:

00:0a.0 Multimedia video controller: Brooktree Corporation Bt878 (rev 02)
	Subsystem: Hauppauge computer works Inc. WinTV/GO
	Flags: bus master, medium devsel, latency 32, IRQ 5
	Memory at e2000000 (32-bit, prefetchable) [size=4K]

only bt878-based cards can have a subsystem ID (which does not mean
that every card really has one).  bt848 cards can't have a Subsystem
ID and therefore can't be autodetected.  There is a list with the ID's
in bttv-cards.c (in case you are intrested or want to mail patches
with updates).


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: video4linux-list@redhat.com.
https://listman.redhat.com/mailman/listinfo/video4linux-list

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 <kraxel@bytesex.org>