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Date: Mon, 25 May 2009 11:21:01 -0400
Message-ID: <9e4733910905250821nf433121s6c161d3f2104b453@mail.gmail.com>
Subject: Re: [PATCH V3 2/4] AC97 driver for mpc5200
From: Jon Smirl <jonsmirl@gmail.com>
To: grant.likely@secretlab.ca
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Cc: linuxppc-dev@ozlabs.org, alsa-devel@alsa-project.org,
	Mark Brown <broonie@opensource.wolfsonmicro.com>
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On Mon, May 25, 2009 at 6:26 AM, Mark Brown
<broonie@opensource.wolfsonmicro.com> wrote:
>> + =A0 =A0 =A0 =A0 =A0 =A0 spin_lock(&psc_dma->lock);
>> + =A0 =A0 =A0 =A0 =A0 =A0 out_be32(&psc_dma->psc_regs->ac97_slots, psc_d=
ma->slots);
>> + =A0 =A0 =A0 =A0 =A0 =A0 spin_unlock(&psc_dma->lock);
>> + =A0 =A0 =A0 =A0 =A0 =A0 break;
>
> This locking looks wrong - I'd expect it to also cover the modification
> of psc_dma->slots? =A0Otherwise it's hard to see what it buys you.

Grant, why are you spin locking around register access?


--=20
Jon Smirl
jonsmirl@gmail.com