From: pjohn@mvista•com (Philby John)
To: linux-arm-kernel@lists•infradead.org
Subject: AACI broken with commit 29a4f2d3
Date: Fri, 26 Mar 2010 19:30:45 +0530 [thread overview]
Message-ID: <4BACBE0D.4000104@mvista.com> (raw)
In-Reply-To: <1269611685.807.55.camel@e102109-lin.cambridge.arm.com>
On 03/26/2010 07:24 PM, Catalin Marinas wrote:
> On Fri, 2010-03-26 at 13:10 +0000, Philby John wrote:
>> On 03/26/2010 06:30 PM, Catalin Marinas wrote:
>>> On Fri, 2010-03-26 at 11:28 +0000, Philby John wrote:
>>>> --- a/sound/arm/aaci.c
>>>> +++ b/sound/arm/aaci.c
>>>> @@ -863,7 +863,11 @@ static int __devinit aaci_probe_ac97(struct aaci *aaci)
>>>> struct snd_ac97 *ac97;
>>>> int ret;
>>>>
>>>> - writel(0, aaci->base + AC97_POWERDOWN);
>>>> + /*
>>>> + * Fix: ac97 read back fail errors by reading
>>>> + * from Power down register
>>>> + */
>>>> + readw(aaci->base + 0x26);
>>>
>>> I still don't understand this. Does aaci->base point to the AACI
>>> registers? There is no register at offset 0x26 but there is one at 0x24
>>> (32-bit AACIIE2).
>>>
>>
>> I think there is a register at 0x26 for AACI, except that its not
>> defined in aaci.h. References in the manual such as "The AC-link signals
>> can be placed in low-power mode, when the power down control
>> and status register (0x26) of the CODEC is programmed to the
>> appropriate value, both AACIBITCLK and AACISDATAIN are brought to, and
>> held at 0.", refer to this register IMHO.
>
> But the above says "the power down control and status register (0x26) of
> the CODEC". So this refers to the AC97 registers rather than the AACI
> registers. Your patch reads from the AACI registers. The AC97 registers
> I think are access with aaci_ac97_(read|write) functions.
>
I think its snd_ac97_read(). But they internally again use readl/writel.
Won't these cause alignment issues again?
next prev parent reply other threads:[~2010-03-26 14:00 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-03-24 13:51 AACI broken with commit 29a4f2d3 Catalin Marinas
2010-03-24 15:10 ` Catalin Marinas
2010-03-24 15:18 ` Will Deacon
2010-03-25 11:12 ` Takashi Iwai
2010-03-25 11:30 ` Russell King - ARM Linux
2010-03-25 11:36 ` Takashi Iwai
2010-03-25 11:50 ` Philby John
2010-03-25 12:02 ` Catalin Marinas
2010-03-25 12:16 ` Russell King - ARM Linux
2010-03-26 11:28 ` Philby John
2010-03-26 13:00 ` Catalin Marinas
2010-03-26 13:10 ` Philby John
2010-03-26 13:24 ` Mark Brown
2010-03-26 13:54 ` Catalin Marinas
2010-03-26 14:00 ` Philby John [this message]
2010-03-26 14:05 ` Catalin Marinas
2010-03-26 14:08 ` Mark Brown
2010-03-26 14:12 ` Catalin Marinas
2010-03-26 14:15 ` Mark Brown
2010-03-26 16:07 ` Philby John
2010-03-26 21:11 ` Takashi Iwai
2010-03-29 7:45 ` Philby John
2010-03-29 7:57 ` Takashi Iwai
2010-04-06 8:12 ` Takashi Iwai
2010-04-06 17:41 ` Russell King - ARM Linux
2010-04-06 18:07 ` Takashi Iwai
2010-04-12 18:31 ` Russell King - ARM Linux
2010-04-13 7:48 ` Takashi Iwai
2010-03-26 22:56 ` Russell King - ARM Linux
2010-03-26 18:15 ` Russell King - ARM Linux
2010-03-25 12:06 ` Russell King - ARM Linux
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