[alsa-devel] [PATCH] ALSA: HDA: Use LPIB Position fix for Intel SCH Poulsbo

[Takashi Iwai]

At Wed, 14 Dec 2011 16:01:08 +0800,
David Henningsson wrote:
> 
> Hi Takashi,
> 
> I just got another position_fix=1 report for the same vendor/deviceID 
> [1] as I sent you the other day, and I assume Eric Piel (a month ago on 
> this list) have the same chipset as well, although I cannot see his 
> alsa-info. I think you have it, can you verify?

You can find it in
	https://lkml.org/lkml/2011/10/18/54
Yes, the controller is same.  Just a different SSID.

> So...can we consider quirking the entire chip to use LPIB, like in the 
> attached patch (untested)?

I guess this would be good.  A question is whether to put this into
3.2 or 3.3.  I think it can be put to 3.2-rc6, although it's a bit
late.  Changing to LPIB is basically harmless.

> If so I'll send another patch later to remove existing quirks for this 
> chipset.

Thanks.


Takashi

> 
> // David
> 
> [1] 
> http://www.alsa-project.org/db/?f=b7421521b8d8a4db3842ee14cdb54b4f440cae5e
> [2 0001-ALSA-HDA-Use-LPIB-Position-fix-for-Intel-SCH-Poulsbo.patch <text/x-patch (7bit)>]
> >From 4f6630ecafc2246c4237f0be5008d4a15cfce733 Mon Sep 17 00:00:00 2001
> From: David Henningsson <david.henningsson at canonical.com>
> Date: Wed, 14 Dec 2011 15:52:30 +0800
> Subject: [PATCH] ALSA: HDA: Use LPIB Position fix for Intel SCH Poulsbo
> 
> Several people with this chipset have reported inconsistent/sloppy
> values for position reporting when the DMA position buffer is used,
> and that setting position_fix=1 have fixed their problems.
> 
> BugLink: https://bugs.launchpad.net/bugs/825709
> Signed-off-by: David Henningsson <david.henningsson at canonical.com>
> ---
>  sound/pci/hda/hda_intel.c |    3 ++-
>  1 files changed, 2 insertions(+), 1 deletions(-)
> 
> diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
> index 0746ab4..f19d7fa 100644
> --- a/sound/pci/hda/hda_intel.c
> +++ b/sound/pci/hda/hda_intel.c
> @@ -2971,7 +2971,8 @@ static DEFINE_PCI_DEVICE_TABLE(azx_ids) = {
>  	/* SCH */
>  	{ PCI_DEVICE(0x8086, 0x811b),
>  	  .driver_data = AZX_DRIVER_SCH | AZX_DCAPS_SCH_SNOOP |
> -	  AZX_DCAPS_BUFSIZE},
> +	  AZX_DCAPS_BUFSIZE | AZX_DCAPS_POSFIX_LPIB }, /* Poulsbo */
> +	/* ICH */
>  	{ PCI_DEVICE(0x8086, 0x2668),
>  	  .driver_data = AZX_DRIVER_ICH | AZX_DCAPS_OLD_SSYNC |
>  	  AZX_DCAPS_BUFSIZE },  /* ICH6 */
> -- 
> 1.7.5.4
>