On 21/01/2021 21:30, Pierre-Louis Bossart wrote:
Am looking at intel_hw_params(). Isn't sdw_stream_add_master() called
for every dai in the dai link.
Yes, that's correct, but again a dai may use one or more ports.
if you defined each port as a dai, and want to call
sdw_stream_add_master() for each port you are doing something the API
was not designed for. There is a 'num_ports' argument for a reason :-)
per master, and that master_rt deals with one or more ports - your
choice. >
A 'stream' is an abstract data transport which can be split across
multiple masters/sales and for each master/slave use multiple ports.
When calling sdw_stream_add_master/slave, you need to provide a
port_config/num_ports to state which ports will be used on that
master/slave when using the stream. That's how we e.g. deal with 4ch
streams that are handled by two ports on each side.
To up-level a bit, the notion of 'stream' is actually very very
similar to the notion of dailink. And in fact, the 'stream' is
actually created for Intel in the dailink .startup callback, so I am
quite in the dark on what you are trying to accomplish.
In qcom case stream is also allocated for in dai startup().
I think we are talking about two different issues,
1>one is the failure I see in sdw_stream_add_master() when I try to
use dai-link dai-id style approach suggested. I will dig this bit more
and collect more details!
2>(Main issue) Ability for slave to select different combination of
ports at runtime based on the mixer setting or active dapm.
All this patch is trying do is the pass this *CURRENT/ACTIVE* static
port mapping between slave and master while setting up the stream.
With the dailink approach number of ports are pretty much static and
may not be required for particular use case. As above example if we
have a headset with button click suppression we would need 2 Ports and
similarly without we only need one port.
As I said above you cannot enable the button click suppression
dynamically *after* the headset capture hw_params/prepare.
That is not true, the ports in this case are selected based on mixer
setting or register state even before stream is setup/started in
hw_params/prepare.
WSA881x codec has pretty much similar setup.
This is not possible with dai-link approach, unless we create two
different dai links for the above example usecase!
The current approach is a worst-case one, where you would create a
single 'headset capture' dailink.
Are you suggesting that we have dailink for each usecase like:
"headset capture"
"Analog MIC1 capture"
"Analog MIC2 Capture"
...
"Analog MIC4 Capture"
...
"DMIC0 capture"
"DMIC1 Capture"
"DMIC2 Capture"
...
"DMIC7 Capture"
..
"Headset Playback"
"Ear Playback"
..
"Aux Playback"
...
this is not really doable!
All am saying is that codec can decide which ports it has to select
based on mixer setting before the stream is setup/started. This updated
mapping between slv port and master ports is passed as part of the
port_config in sdw_stream_add_slave().
--srini
We never envisioned a case where you modify what the definition of
'headset capture' is based on control events, and I really challenge the
fact that it is feasible/realistic. This is really about streaming data
across a bus, and we are limited on what we can do. It's the same
problem that we never modify the number of channels dynamically on a PCM
device.
