[linux-dvb] Problem with init some CAM blocks on TT Budget-S1500 + CI

Akiva Sadovski akivas at scopus.net
Thu Jul 19 23:01:34 CEST 2007

Evgen, all,
   I'm only a stupid newbie in the linuxtv world,
but from my experience with CAM cards it seems to me that Eugen's observation is correct but not precious:
IMHO, the sequence should be (from the DVB-CI standard):
  1) "host now tells the module to use this buffer size by writing a '1' to the SW bit in the Command Register"
   2) "waiting until the FR bit is set"
   3) "writing the size as 2 bytes of data, most significant byte first..."
   4) "At the end of the transfer the host sets the SW bit to '0'. "
this is actually what is coded in  dvb_ca_en50221.c, but I GUESS - I HAVEN'T TESTED IT!!
that the problem is that one have to introduce some delay between writing the buffer size
and setting the SW bit to zero - since according to the standard we have to wait until the transfer (and not
simply the write operation) is finished
         if ((ret = dvb_ca_en50221_write_data(ca, slot, buf, 2)) != 2)
                 return -EIO;
         if ((ret = ca->pub->write_cam_control(ca->pub, slot, 
                 return ret;
Now my question:
  I'm writing the DVB-CI driver for customer made HW developed by the firm I'm working for.
  I'm going to use the dvb-core infrastructure.
  Is there any card which driver already uses the dvb_ca part of the dvb-core ?
  I put an eye on Twinhan 1030 card, but it has the vendor-specific driver which has nothing in common
with dvb-core
Thanks in advance,
Akiva Sadovski
Scopus Video Networks
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