Date: Thu, 06 Nov 2008 15:47:54 -0800 (PST)
Message-Id: <20081106.154754.02648408.davem@davemloft.net>
To: khc@pm.waw.pl
Cc: linux-kernel@vger.kernel.org, khali@linux-fr.org,
       linux-i2c@vger.kernel.org
Subject: Re: I2C from interrupt context?
From: David Miller <davem@davemloft.net>
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References: <m3bpws8ln3.fsf@maximus.localdomain>
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From: Krzysztof Halasa <khc@pm.waw.pl>
Date: Fri, 07 Nov 2008 00:44:48 +0100

[ Fixed i2c list address, it's now hosted at vger ]

> I'm updating my EEPROM console logger and have encountered a problem
> - the logger (as any console) can be called with hardware interrupts
> disabled and/or from interrupt context. It needs to write to I^2C
> (using ARM (Xscale) GPIO) and possibly SMBUS-only EEPROM chip. Is it
> at all supposed to be possible?

Not really.  The I2C operations need to be able to sleep and that's
not allowed in interrupt context.

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