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Date: Fri, 9 Sep 2011 09:31:43 +0800
From: Yong Zhang <yong.zhang0@gmail.com>
To: Clemens Ladisch <clemens@ladisch.de>
Cc: linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@elte.hu,
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        Dan Carpenter <error27@gmail.com>, Joe Perches <joe@perches.com>,
        alsa-devel@alsa-project.org
Subject: Re: [RFC] [PATCH 02/62] mpu401:snd_mpu401_uart_new(): split semantic
 of irq_flags
Message-ID: <20110909013143.GB18249@zhy>
Reply-To: Yong Zhang <yong.zhang0@gmail.com>
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On Thu, Sep 08, 2011 at 10:27:43PM +0200, Clemens Ladisch wrote:
> Yong Zhang wrote:
> > On Thu, Sep 08, 2011 at 03:58:45PM +0200, Clemens Ladisch wrote:
> > > ...
> > > Here, "no interrupt" and "already reserved" actually mean the same thing,
> > > i.e., that the interrupt handling is the responsibility of some other
> > > driver.
> 
> Sorry, after checking the code, I've realized that my description was
> wrong.  irq_flags==0 ("already reserved") means that snd_mpu401_uart_new
> should not try to allocate the interrupt, while irq==-1 ("no interrupt")
> means that the device never issues mpu401 interrupts, so that the mpu401
> code must use a timer to poll the device.
> 
> I'll write a patch that changes this function so that irq<0 means
> "already reserved", and that "no interrupt" gets another bit in the
> info_flags parameter.

Sounds good.

So my patch will be based on yours; or if you have other plan,
how about let's take this patch as a temporary workaroud?

Anyway, you decide it :)

Thanks,
Yong