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Date: Fri, 2 Dec 2005 00:45:40 -0800
From: Eugene Surovegin <ebs@ebshome.net>
To: Sam Song <samlinuxppc@yahoo.com.cn>
Message-ID: <20051202084540.GA16031@gate.ebshome.net>
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Cc: linuxppc-embedded@ozlabs.org
Subject: Re: Can I operate i2c device in a tasklet?
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On Fri, Dec 02, 2005 at 02:20:07PM +0800, Sam Song wrote:
> Hi all,
> 
> I found that once I operated i2c bus like 
> read from i2c device in 2.4.31 kernl in a
> interrupt handler or tasklet, kernel panic
> would happen. Is there any way to make it
> in such case? I need to write sth on RTC
> alarm register with an interrupt event.
> 
> ......
> Scheduling in interrupt
> kernel BUG at sched.c:564!

You cannot access i2c layer from non-process context. Please, search 
mail list archives, this matter was discussed countless number of 
times.

-- 
Eugene