On Tue, 2 May 2006, Manu Abraham wrote:
> Trent Piepho wrote:
> > can be moved into the core at that time. The modcod enum doesn't belong in
> > the public header file since nothing in the public interface uses it.
> >
> >
>
> No, since it is part of the spec and not having anything to do with the
> driver as it is. Some drivers return this explicitly as part of register
> settings , not all drivers do comply.
Why aren't there other enums for constants found in section data? What makes
modcod special?
> > First, how about adding QAM_512 and QAM_1024 in the expected spot. There is
> > already DOCSIS cable modem cardware than can use these modulations. You might
> > want to add VSB_16 too, it's part of the ATSC spec.
> >
> >
>
> ok, will add QAM_512 and QAM_1024
No VSB_16? It's defined in A/53.
> > Third, FE_MOD_AUTO isn't enough. Take the or51132 demodulator. It can
> > demodulate VSB-16, QAM-64, and QAM-256. It can automatically detect QAM-64 vs
> > QAM-256, but not QAM vs VSB. If an app sets the demodulator to MOD_AUTO, what
> > firmware should it load, qam or vsb? There is no way for the driver to know.
> > There is no way for an app to know that it can't just say 'AUTO', it needs to
> > choose QAM or VSB. Maybe it would be enough to add QAM_AUTO and PSK_AUTO
> > demodulations?
> >
>
> The driver has to choose the relevant modulation. Modulation Auto is
> used in the case where the hardware can tell the driver whether it can
> support the same. Or the driver is capable. Current single standard
> (delivery system) drivers/hardware do not support this.
So what you are saying is that the ability of some demodulators to
automatically detect the QAM constellation will no longer be supported?
> > +struct pad_params {
> > + __u8 pad[512];
> > +};
> >
> > You could just make __u8 pad[512] one of members of the delsys union, then you
> > wouldn't have to define this struct at all.
> >
>
> If you see the structure, i have put this struct only for maintaining
> the naming consistency. If i put the pad[512] into the union
> straightaway, that consistency is lost.
You could name it __u8 pad_parms[512].
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