[alsa-devel] [PATCH] ALSA: hda - Use LPIB position fix for Acer AO751h

[David Henningsson]

On 02/28/2013 10:29 AM, Takashi Iwai wrote:
> At Thu, 28 Feb 2013 09:49:23 +0100,
> David Henningsson wrote:
>>
>> On 02/28/2013 08:21 AM, Takashi Iwai wrote:
>>> At Thu, 28 Feb 2013 08:18:30 +0100,
>>> David Henningsson wrote:
>>>>
>>>> The user reports a regression (choppy audio), and that
>>>> position_fix=1 (or position_fix=4) fixes the issue.
>>>>
>>>> This is a Poulsbo controller (8086:811b (rev 07)), so might be
>>>> worth checking if other Poulsbo machines suffer from the same bug.
>>>>
>>>> Cc: stable at vger.kernel.org [v3.7+]
>>>> BugLink: https://bugs.launchpad.net/bugs/1132562
>>>> Signed-off-by: David Henningsson <david.henningsson at canonical.com>
>>>
>>> Please check whether the latest sound git tree works as is.
>>> We enabled the LPIB delay counting for Poulsbo there, and it may fix
>>> most cases.
>>
>> The test was done on a 3.8 based kernel. Isn't LPIB delay counting
>> enabled there as well?
>
> No, it was added fairly recently.
> I didn't put Cc to stable for the commit
> f748abcc5bf62de007019d841f7caba81cc3d673.  If this is confirmed to
> work in general for Poulsbo, we can merge to stable.
>
> But, overall I wonder why POSFIX_LPIB is needed for this device.
> In the recent kernels up to 3.8, LPIB is used as default for Poulsbo.

According to "git describe --contains", this commit was added to 
v3.8-rc6, and released into Ubuntu before this bug was filed. Probably 
this commit is was what caused the regression then, and so the cc to 
stable should be to 3.8+, not 3.7+.

> Takashi
>
>
> Takashi

Have you cloned yourself, or is it just a race condition? :-)

>
>>
>> (Alsa-info is here: https://launchpadlibrarian.net/132247367/AlsaInfo.txt )
>>
>>>
>>>
>>> Takashi
>>>
>>>
>>>> ---
>>>>    sound/pci/hda/hda_intel.c |    1 +
>>>>    1 file changed, 1 insertion(+)
>>>>
>>>> diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
>>>> index 4cea6bb6..3505f1e 100644
>>>> --- a/sound/pci/hda/hda_intel.c
>>>> +++ b/sound/pci/hda/hda_intel.c
>>>> @@ -3114,6 +3114,7 @@ static bool check_hdmi_disabled(struct pci_dev *pci)
>>>>     * white/black-listing for position_fix
>>>>     */
>>>>    static struct snd_pci_quirk position_fix_list[] = {
>>>> +	SND_PCI_QUIRK(0x1025, 0x0244, "Acer AO751h", POS_FIX_LPIB),
>>>>    	SND_PCI_QUIRK(0x1028, 0x01cc, "Dell D820", POS_FIX_LPIB),
>>>>    	SND_PCI_QUIRK(0x1028, 0x01de, "Dell Precision 390", POS_FIX_LPIB),
>>>>    	SND_PCI_QUIRK(0x103c, 0x306d, "HP dv3", POS_FIX_LPIB),
>>>> --
>>>> 1.7.9.5
>>>>
>>>
>>
>>
>>
>> --
>> David Henningsson, Canonical Ltd.
>> https://launchpad.net/~diwic
>>
>



-- 
David Henningsson, Canonical Ltd.
https://launchpad.net/~diwic