[linux-dvb] [PATCH] add DVB-S2 support to frontend.h

[Johannes Stezenbach]

On Thu, Mar 02, 2006, Marcel Siegert wrote:
> On Thursday 02 March 2006 00:53, Johannes Stezenbach wrote:
> > On Wed, Mar 01, 2006, Marcel Siegert wrote:
> > > On Wednesday 01 March 2006 20:08, Johannes Stezenbach wrote:
> > > > On Mon, Feb 27, 2006, Marcel Siegert wrote:
> > 
> > typedef enum fe_type {
> >       FE_QPSK, // legacy, do not use in new applications
> >       FE_QAM,  // legacy, do not use in new applications
> >       FE_OFDM, // legacy, do not use in new applications
> >       FE_ATSC   = 3,
> >       FE_DVB_S  = (1 << 2),
> >       FE_DVB_C  = (1 << 3),
> >       FE_DVB_T  = (1 << 4),
> >       FE_DVB_S2 = (1 << 6)
> > } fe_type_t;
> > 
> > A bit ugly, but would work for both old apps and reporting supported
> > standards for new apps.
> agreed. fixed within my tree, one trap is left :/
> if new frontend driver just return e.g. FE_DVB_T automatically old applications would assume that
> it is an FE_QPSK (which has enum value 0) frontend and fail. 
> i think i will overwork the return values within the frontend drivers to prevent this. 
> patch would be supplied afterwards.

I think FE_GET_INFO should only return the old values 0...3.
We can add a WARN_ON() in dvb_frontend.c to check that
drivers conform.

> so, what are your thoughts on this?
> take the v3 e.g. fe_modulation and let them be enum constants?
> e.g.
> typedef enum fe_code_rate {
> 	FEC_NONE = 0,
> 	FEC_1_2 = 1,
> 	FEC_2_3 = 2,
> 	FEC_3_4 = 3,
> 	FEC_4_5 = 4,
> 	FEC_5_6 = 5,
> 	FEC_6_7 = 6,
> 	FEC_7_8 = 7,
> 	FEC_8_9 = 8,
> 	FEC_AUTO = 9
> } fe_code_rate_t;
> 
> of course i would extend them also to contain the new given modulations fec rates ect.

(A bit confused, I don't get it.)

Maybe we could keep using the existing definitions of
fe_modulation_t etc., and just add new values,
and return a bitset of (1 << VSB_8) etc. in the capabilites.

This would decrease the number of changed lines in frontend.h
dramatically (although, for fe_modulation_t we might want to
add the MOD_ prefix because of 8PSK etc. and provide backwards
comapt #defines).


Johannes