[linux-dvb] Re: [RFC][ANNOUNCE] blindscan: auto search everything

[Holger Waechtler <holger@qanu.de>]

Johannes Stezenbach wrote:
> Roberto Ragusa wrote:
>
> > Holger Waechtler <holger@qanu.de> wrote:
> >
> >
> > > struct dvb_fe_scan_spec {
> > > 	unsigned freq_start;
> > > 	unsigned freq_end;
> > > 	unsigned srate_start;
> > > 	unsigned srate_end;
> > > }
> > >
> > > A similiar approach works for the mt352 DVB-T demod, there the srate 
> > > fields are not required but bandwidth and the scan_weak_channels bit 
> > > have to be configured. What do you think?
> > The auto symbol rate capability is not exactly a scan.
> > Between a start frequency and an end frequency you can find many signals.
> > But in a sr range you can only find one signal.
> >
> > So, the idea of suspending and resuming is not applicable.
> > Having freq and sr together in a struct doesn't look right, as freq
> > is tipically fixed.
> >
> > After rereading what you wrote... are you saying that the core of the
> > blindscan program should be moved into the kernel?
>
> IIRC Holger told me that the mt3?2 frontends can do the whole scan
> automatically? Doing it in the kernel sounds wrong.
No need to do anything in the kernel -- basically the ioctls map pretty 
well the hardware states and the flow charts in the mt312/mt352 Design 
manuals, just fetch them from the Zarlink website and take a look.


> We can always add new ioctls. To me it doesn't feel right
> to cram the scan functionality into the normal FE_SET_FRONTEND ioctl.
I would suggest a new set of FE_SCAN_START/CANCEL/CONTINUE/XXXXX ioctls 
to ensure binary-compability.

Holger