[alsa-devel] [REGRESSION] Sound goes too fast due to 798cb7e897210

[David Henningsson]

(Sorry for removing some CC people from this mail, seems to be a mail 
problem at this end)

2011-10-18 10:46, Takashi Iwai skrev:
> At Tue, 18 Oct 2011 10:38:06 +0200,
> Éric Piel wrote:
>> Op 18-10-11 10:23, Takashi Iwai schreef:
>>> At Tue, 18 Oct 2011 10:10:14 +0200,
>>> Éric Piel wrote:
>> :
>>> If that commit affects, the best fix would be to give a quirk specific
>>> to your device.  Try to pass either position_fix=1 or position_fix=2.
>>> Only one of them should work (likely 2).
>>>
>>> After checking it, you can add it to position_fix_list[] in
>>> sound/pci/hda/hda_intel.c together with PCI SSID.
>> Hello,
>> Thanks for the quick response. Indeed forcing position_fix=1 does fix
>> the bug. I'll not try to make a patch for my device.
> Hm, interesting.  So, in your case, the position-buffer exists and
> reports some valid values, but the values are sloppy actually.
> It's hard to detect in the driver, unfortunately.  The relevant commit
> (and its original fix) were the attempts to detect better, but it
> seems that it fails...
>
> FWIW, the patch below is what I'm committing to the tree.

I'm wondering if quirking this based on PCI Vendor-ID would be better 
than PCI SSID. After all, a broken position buffer should be more of a 
controller chip problem than a controller/codec/config problem, right?

> ---
> From: Takashi Iwai<tiwai at suse.de>
> Subject: [PATCH] ALSA: hda - Add position_fix quirk for Dell Inspiron 1010
>
> The previous fix for the position-buffer check gives yet another
> regression on a Dell laptop.  The safest fix right now is to add a
> static quirk for this device (and better to apply it for stable
> kernels too).
>
> Reported-by: Éric Piel<Eric.Piel at tremplin-utc.net>
> Cc:<stable at kernel.org>
> Signed-off-by: Takashi Iwai<tiwai at suse.de>
> ---
>   sound/pci/hda/hda_intel.c |    1 +
>   1 files changed, 1 insertions(+), 0 deletions(-)
>
> diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
> index e9a2a87..191284a 100644
> --- a/sound/pci/hda/hda_intel.c
> +++ b/sound/pci/hda/hda_intel.c
> @@ -2370,6 +2370,7 @@ static int azx_dev_free(struct snd_device *device)
>   static struct snd_pci_quirk position_fix_list[] __devinitdata = {
>   	SND_PCI_QUIRK(0x1028, 0x01cc, "Dell D820", POS_FIX_LPIB),
>   	SND_PCI_QUIRK(0x1028, 0x01de, "Dell Precision 390", POS_FIX_LPIB),
> +	SND_PCI_QUIRK(0x1028, 0x02c6, "Dell Inspiron 1010", POS_FIX_LPIB),

As seen here there are several relatively similar IDs - even more reason 
to suspect they share the same controller chip perhaps?

// David