At Tue, 02 Jun 2009 08:58:03 +0200, Hector Martin wrote: > > Getting this one to work has annoyed me to no end. > > Short story: this laptop has 5.1 built-in speakers which you *really* > want to use (the not-so-"sub" woofer is what makes the audio above > average for a laptop), so 6-channel support is important (plus a decent > asound.conf to upmix stereo). It also has the 3 typical jacks that ought > to have a selectable mode. And it's based on ALC889, which sucks. > > Rationale/explanations: > > The const_channel_count stuff was added because, for a laptop like this, > you always have 6 channels available (internal speakers) but still need > to set the mode for the 3 external jacks. Therefore, the device always > needs to be in 6-channel mode but there still needs to be a mixer > control for the jack mode. You could use line/mic-in at the same time as > the 6 internal speakers, for example. You might be tempted to make it > even smarter by dynamically switching the max channel count when > headphones are plugged in (therefore muting the internal speakers and > reducing the physical channel count to the jack channel mode), but as a > user I consider this to be harmful because I want the audio to blow up > to 6 channels / upmixed as soon as I unplug the headphones, and having > opened the device while in 2-channel mode would prevent this from > working (and always making 6-channel mode available doesn't do any harm). This change looks OK. > The hardware needs EAPD turned on and the DACs routed to the internal > speaker pins, so the patch adds those verbs. > > The ALC889 CLFE and subsequent (side/aux, here unused) DACs do NOT work > by default, at least here. I wasted much time trying to talk to > Realtek/pshou about this, but they just kept sending me useless updates > to patch_realtek.c that did nothing relevant. In the end I gave up and > brute forced the issue by trying to flip every bit in the proprietary > coefficient registers, and eventually found the two magic registers that > need to be cleared to enable all DACs. I have only heard Acer users > complain, but that might be because ALC889 is pretty new and using 5.1 > (and noticing the missing center/lfe channels) might not be that common. > If this is a generalized issue with all ALC889 systems then those verbs > should probably be moved to a common verb array. Oh, it's a good finding. > The internal mic is untested and probably doesn't work. > > These settings will probably work for other Acer Gemstone laptops with > the same 5.1 speaker config. When identified, those should be added to > the PCI subsystem ID list. The changes you made are fine, but could you reformat the patch as checkpatch.pl-clean and repost? thanks, Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
