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To: linux-arm-kernel@lists.infradead.org
Subject: Re: Locking in the clk API
Cc: linux-sh@vger.kernel.org, linux-kernel@vger.kernel.org,
        Ben Herrenschmidt <benh@kernel.crashing.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        "Uwe =?iso-8859-1?q?Kleine-K=F6nig?=" 
	<u.kleine-koenig@pengutronix.de>
From: Jeremy Kerr <jeremy.kerr@canonical.com>
Date: Mon, 17 Jan 2011 09:27:43 +0800
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Hi all,

Based on the discussion from this thread, my plan is to:

* Change the 'common struct clk' patches to only use a spinlock for locking. 
This means that clk_{en,dis}able will acquire a per-clk spinlock (for enable 
counts), and be callable from atomic contexts.

* Rework the initial docs (posted in the first mail of this thread) to 
illustrate the new locking requirements.

* Request input from the platforms that require clk_enable (etc) to sleep, 
about how we can merge the two implementations.

Russell - is this OK?

Cheers,


Jeremy