[linux-dvb] Problem with latest v4l-dvb hg -Patch?

timf timf at iinet.net.au
Sun Jun 8 04:02:06 CEST 2008


hermann pitton wrote:
> Am Samstag, den 07.06.2008, 13:42 +0800 schrieb timf:
>   
>> timf wrote:
>>     
>>> Mauro Carvalho Chehab wrote:
>>>   
>>>       
>>>> On Fri, 06 Jun 2008 22:59:10 +0200
>>>> hermann pitton <hermann-pitton at arcor.de> wrote:
>>>>
>>>>   
>>>>     
>>>>         
>>>>> Hi,
>>>>>
>>>>> Am Samstag, den 07.06.2008, 03:00 +0800 schrieb timf:
>>>>>     
>>>>>       
>>>>>           
>> <snip>
>>
>> Hi all,
>>
>> Something very strange:
>> If in saa7134-dvb.c I do this:
>>
>> <snip>
>> static int configure_tda827x_fe_kw210(struct saa7134_dev *dev,
>>                 struct tda1004x_config *cdec_conf,
>>                 struct tda827x_config *tuner_conf)
>> {
>>     dev->dvb.frontend = dvb_attach(tda10046_attach, cdec_conf, 
>> &dev->i2c_adap);
>>     if (dev->dvb.frontend) {
>> /*        if (cdec_conf->i2c_gate)
>>             dev->dvb.frontend->ops.i2c_gate_ctrl = tda8290_i2c_gate_ctrl; */
>>         if (dvb_attach(tda827x_attach, dev->dvb.frontend,
>>                    cdec_conf->tuner_address,
>>                    &dev->i2c_adap, tuner_conf))
>>             return 0;
>>
>>         wprintk("no tda827x tuner found at addr: %02x\n",
>>                 cdec_conf->tuner_address);
>>     }
>>     return -EINVAL;
>> }
>> <snip>
>>     case SAA7134_BOARD_KWORLD_DVBT_210:
>> /*        if (configure_tda827x_fe(dev, &kworld_dvb_t_210_config, */
>>         if (configure_tda827x_fe_kw210(dev, &kworld_dvb_t_210_config,
>>                      &tda827x_cfg_2) < 0)
>>             goto dettach_frontend;
>>         break;
>> <snip>
>> then I can scan all available DVB-T channels, and view them.
>> If I leave it as original, it won't scan/view SBS.
>>
>> Can someone tell me what part does this play?
>>
>>         if (cdec_conf->i2c_gate)
>>             dev->dvb.frontend->ops.i2c_gate_ctrl = tda8290_i2c_gate_ctrl;
>>     
>
> Tim,
>
> without looking in any detail, choosed to have enough for myself.
>
> Almost all, but not all, use the tda8290 analog IF demodulator within
> the saa7131e, on prior saa7135 stuff also present as a sepatate chip,
> as an i2c bridge to control the tuner, also if in DVB-T mode ...
>
> To deminish interference on the bus, it is only opened to send the
> tuning bytes and then closed again.
>
> IIRC, on your card are two tda8275a, which could serve as hybrid tuners,
> but on that early design it was choosen to burn some money in favor to
> have a first analog and DVB-T at once solution.
>
> Since you have two tuners, you are not depending on the DVB-T gate stuff
> for DVB-T, which is a point for swichting issues from analog to DVB else
> on single hybrid tuners. To have a digital tuner controlled from the
> analog IF demod some still don't get and cause a lot of trouble.
>
> Cheers,
> Hermann
>
>   
>> I use this:
>> # Australia / Perth (Roleystone transmitter)
>> # T freq bw fec_hi fec_lo mod transmission-mode guard-interval hierarchy
>> # SBS
>> T 704500000 7MHz 2/3 NONE QAM64 8k 1/8 NONE
>> # ABC
>> T 725500000 7MHz 3/4 NONE QAM64 8k 1/16 NONE
>> # Seven
>> T 746500000 7MHz 2/3 NONE QAM64 8k 1/16 NONE
>> # Nine
>> T 767500000 7MHz 3/4 NONE QAM64 8k 1/16 NONE
>> # Ten
>> T 788500000 7MHz 3/4 NONE QAM64 8k 1/16 NONE
>>
>> Regards,
>> Timf
>>     
>
>   
Hi Hermann,

Ah-Hah! So that's it!
I can't tell you how much time I have spent trying to track this fault down!
Very many thanks, Hermann. I am most grateful.
Best Regards,
Timf

P.S.
Should I send in a patch for this?
I am very close to having a patch ready for Avermedia A16D, Avermedia 
E506 (both xc2028-saa7134).



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