[linux-dvb] Setting parameters for or51132 vs. DVB API

Krzysztof Rusocki kszysiu at gmail.com
Mon Mar 13 03:48:22 CET 2006


Got recently HD-3000 and decided to code around it a bit.

I found that or51132 (which is a dual VSB/QAM-B FE?)
driver examines modulation type from dvb_vsb_parameters
structure (which is a member of the union in dvb_frontend_parameters
structure) - see line ~326 (function or51132_set_parameters)
in or51132.c (as of 2.6.16-rc6).

Unless I'm seeing something incorrectly, it causes a problem
in scenario where one wishes to set QAM modulation via
FE_SET_FRONTEND ioctl. Since fe_modulation_t field does
not lie in the same place in dvb_vsb_parameters and
dvb_qam_parameters structures switch() gets the symbol
rate value there (from dvb_qam_parameters).
The call results in the following message:

or51132:Modulation type(5361000) UNSUPPORTED

I worked the problem around by putting fe_modulation_t field as first
in dvb_qam_parameters struct.

How does the API deal with multi-frontends? I mean, what can be
done to fix this? (maybe it doesn't need fixing at all - by current

Would making frontend{0,1} (for or51132) be a reasonable thing to do?


Don't beat too much, first post here

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