On Fri, Aug 16, 2013 at 12:55:41AM +0100, Mark Brown wrote: > On Fri, Aug 16, 2013 at 09:05:04AM +1000, James Cameron wrote: > > On Thu, Aug 15, 2013 at 11:55:34PM +0100, Mark Brown wrote: > > > > End users aren't supposed to see the configuration, the system > > > sound server is supposed to do that - there's some work going on > > > to improve this in PulseAudio at the minute and there's a > > > standard set of helpers in alsa-lib (UCM) which should help > > > implement this for anything else. > > > We certainly don't use PulseAudio, and probably don't use UCM. > > I guess the Fedora installs will? You'd have to try not to. In > general I'd recommend it for any use; it's really rather advanced in > terms of features (I've not seen anything else that has the > dynamically adjusted buffer sizes during playback) and does a great > job of simplifying the system setup down for the applications.
Yes, we try not to. I do not recall the technical arguments in full, Daniel would, but they included very limited processing power, very limited memory, it didn't work when we first tried it, and a suite of applications that use the ALSA controls directly that we would have to port. > > Therefore the number and type of controls exposed to user space > > were actually quite important to us. We have had bad experiences > > with controls being set by uncontrolled applications, being saved > > by alsactl for next boot, and resulting in laptops in the field > > without working audio. For many weeks during development and > > board bringup the default controls didn't get us sound, but > > developers with suitable saved controls had no trouble. This > > delayed us significantly, as test results could not be reproduced. > > Right, this is where not having use case management in your sound > server tends to cause trouble - if your userspace just uses whatever > happens to be lying around on the box and worse saves user settings > then things are going to go wrong. To be honest I'm surprised that > there still aren't problems even with cutting down the number of > controls, so long as there's any configurability people are going to > be able to cause problems. We handle the remaining controls manually in a startup script to ensure their sanity. > You're kind of not supposed to have working audio with the out of > the box setup, or at least you're supposed to just have the default > setup for the CODEC when tends to have everything off. Heh. > > > There's some work going on on this upstream for PulseAudio, it > > > might be good to > > > Your message ends abruptly at this point. > > Oops. I think all I was going to say was something about checking > in with them about what they're up to, it'd probably be useful to > make sure that what they're doing plays nicely. *nod*. -- James Cameron http://quozl.linux.org.au/ _______________________________________________ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
