At Mon, 18 Aug 2008 15:28:00 +0300, Ilkka Tengvall wrote: > > >> the reasoning for the original patch sounds reasonable. The > >> mic volume is tunable, only at the very low range. I recall the laptop > >> came with Win98, and there was no problem then with the sound -> not a > >> HW problem. I have never got this laptop mic working with linux, so > >> this is not anything that broke recently. I see there is > >> check_volume_resolution function which tries to guess some of the > >> register ranges, but maybe it get's it wrong with this HW. > > > > Maybe, maybe not. You should check rather ac97 registers in > > /proc/asound/card0/codec97#0/ac97#0-0+regs. If build with > > CONFIG_SND_DEBUG=y, you can write to the register directly, too. > > See Documentaiton[/sound/alsa]/Procfile.txt. > > > > I checked this file. It seems it gets the regs right for the mic > (range 0x1f). The capture range is 0xf. I don't have the specs to > compare it against, so I assume there is nothing to do more here. Which registers, exactly? > It seems mic value decreases while going up to full, where as capture > increases. I guess the former one is the mic loopback volume (attenuation), so no wonder it behaves so. > Another difference is maybe stereo / mono related, the > capture changes both bytes whereas mic only the other one. Also one > thing, should the mic level be around 0x40 - 0x5f, not 0x0 - 0x1f. The bit 0x40 indicates the mic boost +20dB. Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
