Add bias-T support for RTL-SDR

[jirjirjir]

Hi!

Is it possible to add configurtion checkbox to control bias tee in (supported) RTL-SDR dongles?

e.g.:
https://www.rtl-sdr.com/rtl-sdr-blog-v-3-dongles-user-guide/

Thanx!

[jirjirjir]

Looks like we should manipulate by GPIO#0 with standard rtl-sdr library's func: rtlsdr_set_bias_tee_gpio():

https://github.com/osmocom/rtl-sdr/blob/master/src/rtl_biast.c

[andynoack]

As long as the driver/API supports this setting, this shouldn't be a problem. I think, the challenging point is that it has to be a generic solution for URH, i.e. work with ALL RTL-SDR devices. Thus the driver must be able to identify whether the used RTL-SDR is suitable.

[jirjirjir]

Open pull request:

#1056

[andynoack]

Hey, thanks for opening that pull request. I will have a look but I currently do not have a RTLSDR with me to verify that the code doesn't break anything.

[jirjirjir]

Great, don't hesitate to contact me if you need some assistance for verifying it
Thanx!

[andynoack]

Hey @jirjirjir
there was an error in the ci.yml that made your checks fail. Could you make a new PR with the current master?

[jirjirjir]

Hi!

Done:
#1057