Date: Tue, 10 Mar 2009 15:35:37 +0000
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Timur Tabi <timur@freescale.com>
Cc: linux-kernel@vger.kernel.org, rdreier@cisco.com, jirislaby@gmail.com,
       peterz@infradead.org, will.newton@gmail.com, hancockrwd@gmail.com,
       jeremy@goop.org
Subject: Re: [PATCH v4] introduce macro spin_event_timeout()
Message-ID: <20090310153537.5fd5d84d@lxorguk.ukuu.org.uk>
In-Reply-To: <1236699004-1863-1-git-send-email-timur@freescale.com>
References: <1236699004-1863-1-git-send-email-timur@freescale.com>
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> This primary purpose of this macro is to poll on a hardware register until a
> status bit changes.  The timeout ensures that the loop still terminates if the
> bit doesn't change as expected.  This macro makes it easier for driver
> developers to perform this kind of operation properly.

NAK this - on a lot of platforms 1uS is the wrong timescale. Also we
shouldn't be encouraging this kind of polling by making it very easy to
write.

It might be a useful internal macro for some freescale drivers but if so
it doesn't belong in the core headers

Alan
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