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Typhoon DVB-T Duo Cardbus tuning problems



Hi, Andreas

Andreas Deresch wrote:
When inserting the card after all modules are already loaded (e.g. after
previously ejecting it) tuning digital channels will fail. When opening a
player the card's LEDs dim and the fan slows down.

This is normal, the module has an enormous power consumption if its
fully active.

Loading the tuner module with debug=1 reveals the following dmesg output in
non-working state which is otherwise not present:

tuner 1-004b: Cmd VIDIOC_S_STD accepted for analog TV
tuner 1-004b: switching to v4l2
tuner 1-004b: tv freq set to 400.00
tuner 1-004b: setting tda8290 to system B
tuner 1-004b: tda8290 not locked, no signal?
tuner 1-004b: adjust gain, step 1. Agc: 226, ADC stat: 0, lock: 0
tuner 1-004b: adjust gain, step 2. Agc: 126, lock: 0
tuner 1-004b: adjust gain, step 3. Agc: 24
tuner 1-004b: tv freq set to 400.00
tuner 1-004b: setting tda8290 to system B
tuner 1-004b: tda8290 not locked, no signal?
tuner 1-004b: adjust gain, step 1. Agc: 226, ADC stat: 0, lock: 0
tuner 1-004b: adjust gain, step 2. Agc: 126, lock: 0
tuner 1-004b: adjust gain, step 3. Agc: 24

AFAICT this is due to the call to set_tvnorm(dev,&tvnorms[0]) in
saa7134_video_init2. AFAIK the tda8290 is in fact the analog tuner on duo
cards!? I don't see any other differences, though.

These messages are normal. The TDA8290 actually is the IF chip for analog TV.

Upon first insertion of the card the tuner module seems to be autoloaded
after this line of code is executed. Tuning and watching DVB-T then works as
expected. Only when the tuner module is already loaded when the card is
inserted does it fail.


Obvious workaround is to remove the tuner module after each card ejection,
but what is the correct fix? I don't know enough about the inner workings of
the driver(s), otherwise I would have submitted a patch.


That is interesting...
I developed the driver for the module labeled Lifeview but i still think
they are identical. I will get one let again tomorrow.
I must say i never tried to  remove and reinsert the card with the driver
loaded. So..
What i don't understand right now is: the saa7134-dvb module is independent
of the tuner module. If this one causes a side effect, i right now have no
idea what it is.
In your experiment, did you also unload all other modules?
Can you please repeat your experiment with the debug=1 option to saa7134?
Does the driver report "hwinit1" in both cases?

Best regards
   Hartmut

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