[linux-dvb] no write access to CAM? /dev/dvb/adapter0/ca0

[Manu Abraham]

Simon Baxter wrote:
>> I've just added an Irdeto CI adapter to my TT-1500 Budget card.  But I
> can't
>> decrypt channels, and get the following errors:
>>
>> In /var/log/messages:
>> Apr 30 19:31:26 media1 vdr: [2774] CAM 1: module present
>> Apr 30 19:31:28 media1 kernel: dvb_ca adapter 0: DVB CAM detected and
>> initialised successfully
>> Apr 30 19:31:28 media1 vdr: [2774] CAM 1: module ready
>> Apr 30 19:31:29 media1 vdr: [2774] ERROR: can't write to CI adapter on
>> device 0: Input/output error
>>
>>
>> In dmesg:
>> dvb_ca adapter 0: DVB CAM detected and initialised successfully
>> dvb_ca adapter 0: DVB CAM detected and initialised successfully
>> dvb_ca adapter 0: DVB CAM detected and initialised successfully
>> (etc)
> 
> I've tried this with gnutv and get similar results:
> 
> [root at media1 gnutv]# dmesg | grep DVB
> DVB: registering new adapter (TT-Budget-C-CI PCI).
> DVB: registering frontend 0 (ST STV0297 DVB-C)...
> dvb_ca adapter 0: DVB CAM detected and initialised successfully
> dvb_ca adapter 0: DVB CAM detected and initialised successfully
> 
> 
> [root at media1 gnutv]# ./gnutv -cammenu
> en50221_tl_poll: CAWrite failed
> en50221_stdcam_llci_poll: Error reported by stack:-2

Have been looking at that bug. The bug is that the driver times out. The
bug was discovered by julian (adding his CC)

> 
> What is going on here?  Can anyone help?

The bug is that the debi bus looks unlocked and that debiread/write
doesn't look serialized, using uselocks creates it's own set of problems.