[linux-dvb] [PATCH] dst_ca: ca_info and application_info

Henrik Sjöberg hsjo at epact.se
Tue Jan 17 15:32:16 CET 2006

> -----Original Message-----
> From: Sigmund Augdal Helberg [mailto:sigmund at snap.tv]
> Sent: den 17 januari 2006 12:27
> To: Henrik Sjoberg
> Cc: linux-dvb at linuxtv.org
> Subject: Re: [linux-dvb] [PATCH] dst_ca: ca_info and application_info
> On Tue, 2006-01-17 at 10:09 +0100, Henrik Sjoberg wrote:
> > > On Mon, 2006-01-09 at 14:33 +0100, Henrik Sjoberg wrote:
> > >> Hi,
> > >> Today, application info can be enquired from the dst_ca ca using the
> > ioctl
> > >> CA_APP_INFO_ENQUIRY. However, the answer which is returned is the raw
> > data
> > >> of the answer from the HW and not formatted as described in EN-50221.
> > (Which is probably why there is a "only for debugging"-comment in the
> code).
> > >> I have made patch which
> > >> 1. Restructures the answer from CA_APP_INFO_ENQUIRY to conform with
> > application_info (EN50221:1997, p.28).
> > >> 2. Adds support for CA Info Enquiry, conforming to EN50221:1997,
> > Since this will break dst_test -a, a patch is also needed for dvb-apps
> to
> > >> correct dst_test for application info and add support for ca info. It
> > would be great if anyone more familiar with the specs. could take a look
> > at it and see if it looks ok. It would also be good to have some testing
> > from some Twinhan CI-card users as well.
> > > I'm really happy to see someone pick up on the twinhan ci code. As
> soon
> > as I find some time I will try this out and proof-read the code
> > > somewhat. And if it turns out to be correct I'll update vlc to handle
> > the correct app info, and use the ca info as well.
> > >
> > > Where did you get the magic command? And do you have commands for
> > remaining en50221 objects? I'm particularly interrested in the mmi
> > >
> > > Regards,
> > > Sigmund
> >
> > I have implemented a rudimentary HLCI support for mythtv and the
> structure
> > there needed the ca_info to be implemented in the driver.
> All my tests shows that the ca_info isn't actually needed for hlci.
> ca_info is normally used to filter away ca descriptors not supported by
> the cam, but all evidence shows that the twinhan firmware does this for
> us. Anyway I can imagine the code looking prettier when ca_info is
> known.
> >
> > By 'magic command' I assume you mean command to the hardware. I
> discovered
> > that all information that was needed for the ca_info was present in the
> > request for the slots_caps.
> >From your patch:
> +       static u8 slot_command[8] = {0x07, 0x40, 0x00, 0x00, 0x02, 0x00,
> 0x00, 0xff};
> This is different from the slot_caps query which is:
>         static u8 slot_command[8] = {0x07, 0x40, 0x02, 0x00, 0x02, 0x00,
> 0x00, 0xff};

Ah, yes. I was interested in what the different commands to the hw was used
for and was disassembling the windows driver. I noticed that the caps
command in those drivers differed on the third byte and I tried it out. It
seemed like it didn't change anything for me.
As I said, I'm lacking documentation of the hardware.
> So I imagined you had some kind of listing of usable commands, that you
> used to find this one, and that this list included the needed parts for
> mmi. If you don't have such a list I'll have to wait for Manu.

I noticed some mmi commands as well when disassembling. However, I don't
know exactly what they do and how the answer is interpreted.
> Btw: Have you experienced i2c errors in the logs ("trying to recover
> from previous errors" and "RDC 8820 RESET"), and if so, do descrambling
> stop for you at these points?
Not that I have noticed. I haven’t used the descrambling for a longer time
on channels. I have only tried it out and tested that it works to switch
between channels and so. 

> Regards,
> Sigmund
> >
> > For the mmi commands I can not help you much for now on how to access it
> > in the hardware. Maybe Manu can be of assistance?
> >
> > Regards,
> > Henrik
> >

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