2.6.25-git regression with snd-hda-intel on Dell XPS M1330, no analog sound

[Andre Tomt <andre@tomt.net>]

[Rafael & Matthew: this is a resend - original was sent to wrong 
linux-kernel address. Also updated, so just ignore the earlier emails.]

With 2.6.25-git I lost sound on my Dell XPS M1330 laptop. There seems to 
be two issues at hand here: 1. Analog output is listed, but emits no 
sound (just silence), and 2. Digital out device is missing.

Issue #1 is bisected in this thread. #2 is still work in progress, and 
will be posted as a separate thread.

git bisect nailed down the missing audio issue to this commit:
> 2f32d909f3a85a96074801f6cf20f93324f87646 is first bad commit
> commit 2f32d909f3a85a96074801f6cf20f93324f87646
> Author: Matthew Ranostay <mranostay@embeddedalley.com>
> Date:   Thu Jan 10 13:06:26 2008 +0100
> 
>     [ALSA] hda: STAC9228 VT fixes
> 
>     Moved 2 systems PCI_QUIRK values to STAC_DELL_BIOS. Also the second
>     front HP jack is incorrect defined in the BIOS VT's for some laptops,
>     this patch corrects this.
> 
>     Signed-off-by: Matthew Ranostay <mranostay@embeddedalley.com>
>     Signed-off-by: Takashi Iwai <tiwai@suse.de>
>     Signed-off-by: Jaroslav Kysela <perex@perex.cz>
> 
> :040000 040000 98d7878c8addc0b1595d4b42524cf9cb6cf8759a e32416d5e02694320e8aac369b260d86b2eb2508 M   sound

lspci:
> 00:1b.0 Audio device [0403]: Intel Corporation 82801H (ICH8 Family) HD Audio Controller [8086:284b] (rev 02)
>         Subsystem: Dell Unknown device [1028:0209]
>         Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx+
>         Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
>         Latency: 0, Cache Line Size: 64 bytes
>         Interrupt: pin A routed to IRQ 217
>         Region 0: Memory at febfc000 (64-bit, non-prefetchable) [size=16K]
>         Capabilities: [50] Power Management version 2
>                 Flags: PMEClk- DSI- D1- D2- AuxCurrent=55mA PME(D0+,D1-,D2-,D3hot+,D3cold+)
>                 Status: D0 PME-Enable- DSel=0 DScale=0 PME-
>         Capabilities: [60] Message Signalled Interrupts: Mask- 64bit+ Queue=0/0 Enable+
>                 Address: 00000000fee0300c  Data: 414a
>         Capabilities: [70] Express (v1) Root Complex Integrated Endpoint, MSI 00
>                 DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s unlimited, L1 unlimited
>                         ExtTag- RBE- FLReset-
>                 DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
>                         RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop+
>                         MaxPayload 128 bytes, MaxReadReq 128 bytes
>                 DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr+ TransPend-
>                 LnkCap: Port #0, Speed unknown, Width x0, ASPM unknown, Latency L0 <64ns, L1 <1us
>                         ClockPM- Suprise- LLActRep- BwNot-
>                 LnkCtl: ASPM Disabled; Disabled- Retrain- CommClk-
>                         ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
>                 LnkSta: Speed unknown, Width x0, TrErr- Train- SlotClk- DLActive- BWMgmt- ABWMgmt-
>         Capabilities: [100] Virtual Channel <?>
>         Capabilities: [130] Root Complex Link <?>
>         Kernel driver in use: HDA Intel
>         Kernel modules: snd-hda-intel
> 00: 86 80 4b 28 06 05 10 00 02 00 03 04 10 00 00 00
> 10: 04 c0 bf fe 00 00 00 00 00 00 00 00 00 00 00 00
> 20: 00 00 00 00 00 00 00 00 00 00 00 00 28 10 09 02
> 30: 00 00 00 00 50 00 00 00 00 00 00 00 0a 01 00 00
> 40: 01 00 00 03 00 00 00 00 00 00 00 00 00 00 00 00
> 50: 01 60 42 c8 00 00 00 00 00 00 00 00 00 00 00 00
> 60: 05 70 81 00 0c 30 e0 fe 00 00 00 00 4a 41 00 00
> 70: 10 00 91 00 c0 0f 00 00 00 08 10 00 00 00 00 00
> 80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> 90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> c0: 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 00
> d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> f0: 00 00 00 00 00 00 00 00 86 0f 05 00 00 00 00 00