[linux-dvb] Re: Twinhan CA

[Manu Abraham <manu@kromtek.com>]

On Sat November 27 2004 10:17 pm, Johannes Stezenbach wrote:
> Manu Abraham wrote:
> > On Sat November 27 2004 5:26 pm, Ralph Metzler wrote:
> > > I wrote a small test program which will get the PMT for a given
> > > PNR/ServiceID, convert it to CA_PMT and send it (with just the CA
> > > system ids suported by the CAM) to the CAM. This is working fine.
> >
> > The ASIC requires the info as per EN50221 CA PMT list management, plus a
> > couple of magic words to the MCU. Only PID's and program numbers does not
> > work with all CAM's. Some CAM's do work. With the CA PMT List management
> > everything works fine.
> >
> > I got this verified from the manufacturer.
>
> ...
>
> > > standard En50221 packets minus header and length field plus their own
> > > header we could also just send those. The driver would just have to
> > > exchange the headers from standard En50221 to Twinhan and vice versa.
> > > Or do you want to use extra ioctls like Twinhan does in their API?
> >
> > I think the extra ioctl's would be useful, considering the release of the
> > new CI cards. One more is due in Dec.
>
> My 2¢ on this issue: If the Twinhan CI interface doesn't prevent
> you from sending/receiving raw TPDUs, then we should use that
> and be done with it. There are working solutions (libdvb, vdr)
> which implement the remainder in user space. 

There is no Transport Layer.. There is only Application layer.
> Vendor specific 
> ioctls for CI are bad.

They are required in this case, if full features need be exploited. Else the 
driver would become jut like the initial original application which Twinhan 
had, reads from the DMA buffer in userspace in large chunks

Manu
>
> Johannes