On Fri, 2008-04-25 at 11:42 +0200, Takashi Iwai wrote:
At Fri, 25 Apr 2008 11:30:40 +0200, Daniel Mack wrote:
On Fri, Apr 25, 2008 at 11:22:10AM +0200, Takashi Iwai wrote:
Add more routing controls to AIC3x chips to allow things like routing the left PGA input to right line out.
Signed-off-by: Daniel Mack daniel@caiaq.de
It should be implemented rather with stereo mixer switches in general...
Not necessarily as left and right inputs of let's say the line input can be used for entierly different things. Same is counts for the outputs. This is the case in my setup and I guess for mobile phone (what the chip is made for) there will be more cases.
Controlling them with stereo mixers would just cause more confusion in the already over-engineered chip, I fear.
Well, for such a complex system, switches don't suite well as the end point representation. A switch is the easiest way to implement in a driver, but you'll have a mess in the end if there are too many switches.
We can hide these in an higher abstraction layer (e.g. alsa-lib mixer interface) if it were implemented. Otherwise, think about a more reasonable (can be less-flexible though) setup, e.g. using enum controls to represent the hardware configuration intead of combination of lots of switches.
I'm not too keen on using custom enums to represent the use cases on embedded devices - I don't think it's very application independent. I'd rather provide all the controls in the codec and have user space abstract the use cases (as above) in a standard device neutral API.
The main problem I think we have on phones is that the audio routing is incredibly complex compared to a PC. i.e. a lot of mixers/controls have to be changed when we have a use case change.
Honestly, in the case of existing asoc drivers, I don't care much, and likely I'll let it be. But, this is an issue we need to reconsider for the future development.
Fwiw, the ALSA scenario/use case library (future/current development to handle the above abstractions) now has a public git. The code compiles, although doesn't do much atm except parsing and storing the current sound card state. :-/
I'm looking for some help in completing the library as it's quite low on my todo list atm. Imo it's probably only about a couple of days work involved (by someone knowledgeable with alsa-lib) to get something basic working. I can give git commit access if required. Any takers ?
Liam