[linux-dvb] Newbie driver writer's questions

Roberto Ragusa mail at robertoragusa.it
Wed Feb 23 17:09:39 CET 2005

Leonid Podolny wrote:
> 1) The PDF file at LinuxTV.org seems to explain the upper API, i.e. the
> API from the application to the linuxtv framework. I'm unable to find
> the bottom API, i.e. the functions that I have to implement as a driver
> writer.
> 2) The cards don't do any demuxing -- they provide the transport stream
> as-is. 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?
> 3) Is there some sort of a skeleton driver existing?

Have a look at the skystar2 driver.
The chip has hardware filters and uses them to reduce the data moved on
the PCI bus, but when too many PIDs are requested at the same time it
switches into "whole bandwith" mode, that is the transport stream
is fully passed to the upper layer which take cares of demuxing
according to what the apps have requested.

You will be always in "whole bandwidth mode" as you have no filters, so
your driver will be simpler than the Skystar2.

I assume your card will be very cheap (so, interesting). Can you say
something more about it? DVB-S? DVB-T?

Best regards.

    Roberto Ragusa    mail at robertoragusa.it

More information about the linux-dvb mailing list