Re: [gentoo-user] The Great Macbook Update 1: Audio

[Bruce Hill <bruce@slackwarebox.com>]

On Thu, Dec 24, 2009 at 09:53:43PM +0000, bn wrote:
> Hi,
> 
> I am updating my Macbook Pro installation. While many programs I updated
> often, the basics (Xorg, kernel, etc.) were taking dust since... well, a
> lot. I only found time with these holidays. This is therefore probably
> the first thread of a long series...
> 
> To make it short: The machine is a late-2007 Macbook Pro which I updated
> from vanilla-sources 2.6.24-rc6 to gentoo-sources-2.6.31.6. Everything
> essential seems to work fine, apart from audio. Audio card is
> recognized, the hardware (from lshw) is:
> 
> description: Audio device
> product: 82801H (ICH8 Family) HD Audio Controller
> vendor: Intel Corporation
> physical id: 1b
> bus info: pci@0000:00:1b.0
> version: 03
> width: 64 bits
> clock: 33MHz
> capabilities: pm msi pciexpress bus_master cap_list
> configuration: driver=HDA Intel latency=0 module=snd_hda_intel
> 
> The situation is a classic: everything *seems* recognized, no program
> compalins, *but* I hear only silence, no audio.
> 
> alsamixer and kmix agree on everything being turned on. Where should I
> try to look?

I've never done this for a Mac (and it's kernel) ... however, let's try:

First issue "cat /proc/asound/card0/codec#* | grep Codec"

Which codec does your HDA Intel use? Then check if it's in your kernel:

zgrep 'CONFIG_SND_HDA_CODEC' /proc/config.gz

Your codec might not be easy to determine, such as mine:
jeremiah ~ # cat /proc/asound/card0/codec#* | grep Codec
Codec: Analog Devices AD1984
jeremiah ~ # zgrep 'CONFIG_SND_HDA_CODEC' /proc/config.gz
# CONFIG_SND_HDA_CODEC_REALTEK is not set
CONFIG_SND_HDA_CODEC_ANALOG=y
# CONFIG_SND_HDA_CODEC_SIGMATEL is not set
# CONFIG_SND_HDA_CODEC_VIA is not set
# CONFIG_SND_HDA_CODEC_ATIHDMI is not set
# CONFIG_SND_HDA_CODEC_NVHDMI is not set
# CONFIG_SND_HDA_CODEC_INTELHDMI is not set
# CONFIG_SND_HDA_CODEC_CIRRUS is not set
# CONFIG_SND_HDA_CODEC_CONEXANT is not set
# CONFIG_SND_HDA_CODEC_CA0110 is not set
# CONFIG_SND_HDA_CODEC_CMEDIA is not set
# CONFIG_SND_HDA_CODEC_SI3054 is not set

However, in the Help for CONFIG_SND_HDA_CODEC_ANALOG we read:
Say Y here to include Analog Device HD-audio codec support in
snd-hda-intel driver, such as AD1986A.

Research told me that the AD1984 and AD1986A use the same module,
and I find AD1984 in this file:
/lib/modules/2.6.32.2/kernel/sound/pci/hda/snd-hda-codec-analog.ko

If you need more assistance, post the output of:
"cat /proc/asound/card0/codec#* | grep Codec" and
"zgrep 'CONFIG_SND_HDA_CODEC' /proc/config.gz"

If those are correct, it's time to look at alsa settings. Run this:
http://slackwarebox.dyndns.org:88/HOW-TOs/alsa-info.sh
ALSA-Info script v 0.4.58 and give a link to the location of your
output.
-- 
"Experience is a hard teacher because she gives the test first, the
lesson afterward. But properly learned, the lesson forever changes
the man."