linux-kernel - Re: [RFC] w1: Disable irqs in critical section

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Message-ID: <20110907175059.GA12074@ioremap.net>
Date:	Wed, 7 Sep 2011 21:50:59 +0400
From:	Evgeniy Polyakov <zbr@...emap.net>
To:	Jan Weitzel <j.weitzel@...tec.de>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: [RFC] w1: Disable irqs in critical section

On Wed, Sep 07, 2011 at 10:48:32AM +0200, Jan Weitzel (j.weitzel@...tec.de) wrote:
> Interrupting w1_delay in w1_read_bit results in missing the low level
> on the w1 line and receiving "1" instead of "0".
> Adding local_irq_save / local_irq_restore around the critical section

This means that CPU will be essentially stuck for 15 useconds for every
bit transferred, doesn't really look like a good idea.

Are you absolutely sure that missing bit is because of timings and not
some other bug?

-- 
	Evgeniy Polyakov
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