On 27-12-2011 10:11, Andreas Oberritter wrote:
> On 27.12.2011 02:07, Mauro Carvalho Chehab wrote:
>> DVB-S and DVB-T, as those were the standards supported by DVBv3.
>
> The description seems to be incomplete.
>
>> New standards like DSS, ISDB and CTTB don't fit on any of the
>> above types.
>>
>> while there's a way for the drivers to explicitly change whatever
>> default DELSYS were filled inside the core, still a fake value is
>> needed there, and a "compat" code to allow DVBv3 applications to
>> work with those delivery systems is needed. This is good for a
>> short term solution, while applications aren't using DVBv5 directly.
>>
>> However, at long term, this is bad, as the compat code runs even
>> if the application is using DVBv5. Also, the compat code is not
>> perfect, and only works when the frontend is capable of auto-detecting
>> the parameters that aren't visible by the faked delivery systems.
>>
>> So, let the frontend fill the supported delivery systems at the
>> device properties directly, and, in the future, let the core to use
>> the delsys to fill the reported info::type based on the delsys.
>>
>> Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
>> ---
>> drivers/media/dvb/dvb-core/dvb_frontend.c | 13 +++++++++++++
>> drivers/media/dvb/dvb-core/dvb_frontend.h | 8 ++++++++
>> 2 files changed, 21 insertions(+), 0 deletions(-)
>>
>> diff --git a/drivers/media/dvb/dvb-core/dvb_frontend.c b/drivers/media/dvb/dvb-core/dvb_frontend.c
>> index 8dedff4..f17c411 100644
>> --- a/drivers/media/dvb/dvb-core/dvb_frontend.c
>> +++ b/drivers/media/dvb/dvb-core/dvb_frontend.c
>> @@ -1252,6 +1252,19 @@ static void dtv_set_default_delivery_caps(const struct dvb_frontend *fe, struct
>> const struct dvb_frontend_info *info = &fe->ops.info;
>> u32 ncaps = 0;
>>
>> + /*
>> + * If the frontend explicitly sets a list, use it, instead of
>> + * filling based on the info->type
>> + */
>> + if (fe->ops.delsys[ncaps]) {
>> + while (fe->ops.delsys[ncaps] && ncaps < MAX_DELSYS) {
>> + p->u.buffer.data[ncaps] = fe->ops.delsys[ncaps];
>> + ncaps++;
>> + }
>> + p->u.buffer.len = ncaps;
>> + return;
>> + }
>> +
>
> I don't understand what this is trying to solve. This is already handled
> by the get_property driver callback.
>
> dtv_set_default_delivery_caps() only sets some defaults for drivers not
> implementing get_property yet.
dtv_set_default_delivery_caps() does the wrong thing for delivery systems
like ISDB-T, ISDB-S, DSS, DMB-TH, as it fills data with a fake value that
is there at fe->ops.info.type.
The fake values there should be used only for DVBv3 legacy calls emulation
on those delivery systems that are not fully compatible with a DVBv3 call.
At the end, I think we should deprecate the fe->ops.info.type, as its
contents is not reliable (as it can represent something else).
Btw, there are several places at dvb_frontend.c that uses the info.type
to assume the delivery system. This leads DVB core to do the wrong assumptions
for non-DVBv3 supported systems. The right way is to use a new field that
really represents the supported delivery systems by a given frontend, instead
of relying on fe->ops.info.type.
> --
> To unsubscribe from this list: send the line "unsubscribe linux-media" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
