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Date:   Thu, 27 Apr 2023 09:46:55 +0000
From:   Charles Keepax <ckeepax@opensource.cirrus.com>
To:     Mark Brown <broonie@kernel.org>
CC:     Lee Jones <lee@kernel.org>, <patches@opensource.cirrus.com>,
        <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] mfd: wm831x: Use maple tree register cache
Message-ID: <20230427094655.GD68926@ediswmail.ad.cirrus.com>
References: <20230419-mfd-wm831x-maple-v1-1-e03e39d7bb0b@kernel.org>
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On Tue, Apr 25, 2023 at 07:03:33PM +0100, Mark Brown wrote:
> regmap has introduced a maple tree based register cache which makes use of
> this more advanced data structure which has been added to the kernel
> recently. Maple trees are much flatter than rbtrees, meaning that they do
> not grow to such depths when the register map is sparse which makes access
> a bit more efficient. The maple tree cache type is still a bit of a work
> in progress but should be effective for some devices already.
> 
> The wm831x devices have a pretty sparse register map and being always on
> devices never do cache syncs so don't hit the major current disadvantage
> so they should be good candiates for using the maple tree cache.  Update
> to do so, there should be little if any visible difference at runtime.
> 
> Signed-off-by: Mark Brown <broonie@kernel.org>
> ---

Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>

Thanks,
Charles