Re: regression on imac G3: problems with sound

[risto.suominen@gmail.com]

2008/10/1, Mariusz Kozlowski <m.kozlowski@tuxland.pl>:
> Hello,
>
> 	I found that on my old iMac G3 aumix behaves weird on newer (up to
> 2.6.27-rc8) kernels. The sound is only present _when_ muted and is quiet
> I'd say 10% of 'normal' max level. If you turn the volume up - the box is
> silent.
> If you unmute - the box is silent. 100% reproducible.
>
> Bisection result is a bit surprising as it seems it was introduced some time
> ago,
> in 2.6.25 ~ 2.6.26-rc1 window:
>
> commit a8c2a6bf464d983c642c8b8b001a57aabbf76673
> Author: Risto Suominen <Risto.Suominen@gmail.com>
> Date:   Thu Apr 17 17:55:30 2008 +0200
>
>     [ALSA] snd-powermac: AWACS and Screamer mixers for PM7500, Beige, and
> iMac SL
>
>     Add mixer controls and correct headphone detection bits for PowerMacs
>     7300/7500 (AWACS) and G3 Beige (Screamer), and iMac G3 Slot-loading
>     (Screamer).
>
>
> 	Mariusz
>
>
>
> processor       : 0
> cpu             : 740/750
> temperature     : 52 C (uncalibrated)
> clock           : 400.000000MHz
> revision        : 2.2 (pvr 0008 0202)
> bogomips        : 49.79
> timebase        : 24967326
> platform        : PowerMac
> model           : PowerMac2,1
> machine         : PowerMac2,1
> motherboard     : PowerMac2,1 MacRISC2 MacRISC Power Macintosh
> detected as     : 66 (iMac FireWire)
> pmac flags      : 00000014
> L2 cache        : 512K unified
> pmac-generation : NewWorld
>
> 0000:00:0b.0 Host bridge: Apple Computer Inc. UniNorth AGP
> 0000:00:10.0 Display controller: ATI Technologies Inc Rage 128 RL/VR AGP
> 0001:10:0b.0 Host bridge: Apple Computer Inc. UniNorth PCI
> 0001:10:12.0 FireWire (IEEE 1394): Texas Instruments TSB12LV23 IEEE-1394
> Controller
> 0001:10:13.0 Ethernet controller: Digital Equipment Corporation DECchip
> 21142/43 (rev 41)
> 0001:10:17.0 Class ff00: Apple Computer Inc. KeyLargo Mac I/O (rev 02)
> 0001:10:18.0 USB Controller: Apple Computer Inc. KeyLargo USB
> 0001:10:19.0 USB Controller: Apple Computer Inc. KeyLargo USB
> 0002:20:0b.0 Host bridge: Apple Computer Inc. UniNorth Internal PCI
>
>
Mariusz, thank you for the report. This is my fault. Sorry.

PowerMac2,1 seems to have the mute bit reversed compared to later
models, PowerMac2,2 and PowerMac4,1, which I was using for testing my
changes.

This has been fixed in a later patch that should be included in kernel
2.6.27, I believe.

Takashi, when was this (or will be) included? I sent two patches on 2008-08-25.

Risto