[linux-dvb] Newbie driver writer's questions

[Patrick Boettcher]

On Wed, 23 Feb 2005, Roberto Ragusa wrote:

Hi,

> Leonid Podolny wrote:
>> Where an actual software demuxing takes place? Do I have to reimplement 
>> it at the driver or does a framework take care of it for me?

Linux DVB contains a software demuxer. You can easily register and feed 
it.

>> 3) Is there some sort of a skeleton driver existing?
>
> Have a look at the skystar2 driver.

No offense, Roberto, but for a newbie to dvb and linux drivers, the 
skystar2.c is not so good. I for myself referred to the usb drivers, when 
I started to work on a drivers last year.

And, I heard, that the PCI initialization in the skystar2.c is not yet a 
good reference, too.

Leonid,

Probably you'll have to write two drivers. A bus driver (PCI or USB or 
whatever) and a frontend driver.

Your bus driver needs to register some dvb-stuff (dvb_adapter, 
demux-device, maybe an i2c-adapter). For the dibusb-driver I put every 
bigger part in a separate file. For the dvb stuff (which is located
in the bus-driver) you can look into dvb-dibusb-dvb.c for an example.

Additionally you have to register an i2c adapter, if your 
frontend/demodulator is connected via i2c. See the dvb-dibusb-fe-i2c.c 
or flexcop-i2c.c in current dvb-kernel (b2c2/) for an example.

Then of course you have to write a frontend-driver, or (with some luck) 
you can use an existing driver. Depending on your type (-T/-S/-C) you 
should refer to appropriate, existing frontend-source. It's not too
complicated.

Will you driver be OpenSource?

best regards,
Patrick.

--
   Mail: patrick.boettcher at desy.de
   WWW:  http://www.wi-bw.tfh-wildau.de/~pboettch/