[linux-dvb] [PATCH] 8PSK/BPSK DVB-S/S2 support

Marcel Siegert mws at linuxtv.org
Wed Feb 22 16:10:41 CET 2006

On Saturday 18 February 2006 16:08, Alan Nisota wrote:
> This is a trivial patch which adds capabilities for 8PSK (QPSK_8) and
> BPSK (QPSK_B) modes to frontend .h
> The change does not affect the size of the dvb_frontend_parameters, so
> it is backwards compatible with all software (for cards that don't
> utilize the 'modulation' value.
> I am not sure what to do about mixing software that does not support
> 8PSK modulation with hardware that does.  In this case, there is the
> small chance that a program does not initialize the
> dvb_frontend_parameters, structure and that the value in the
> 'modulation' variable equals QPSK_8 or QPSK_B in which case any card
> looking for these will be switched to the wrong mode.
> Perhaps an additional 'union' is necessary to prevent that, however,
> these cards obey  qpsk commands as well, and software I've looked at
> seems to assume a card uses only one of the available modes
> (qpsk/qam/vsb/ofdm) so it would mean a lot more coding to applications
> to treat 8PSK/BPSK as different from QPSK.
> Additionally, there is now only room for 8 additional capabilities in
> the fe_caps enum.
> I am open to other suggestions.
> This patch only includes the changes needed for frontend.h.  As the
> last of three patches, I'll include one which uses these changes to
> support 8psk/bpsk on the genpix board, but I'd prefer to get feedback
> that the implementation I used here s the right strategy
> Signed off by: Alan Nisota <alannisota at gmail.com>
hi alan,

last november we discussed parts of the dvb-s2 issue.

we came to some agreements, that binary compatibility is absolutely important.

at the moment i am preparing some patches to provide dvb-s2 functionallity,
keeping backwards compability.

if you won't mind, i will add your additional defines within my set.

would that be ok for you?


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