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Date:   Tue, 7 Aug 2018 19:06:27 +0200
From:   Boris Brezillon <boris.brezillon@bootlin.com>
To:     Janusz Krzysztofik <jmkrzyszt@gmail.com>
Cc:     Linus Walleij <linus.walleij@linaro.org>,
        Jonathan Corbet <corbet@lwn.net>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        David Woodhouse <dwmw2@infradead.org>,
        Brian Norris <computersforpeace@gmail.com>,
        Marek Vasut <marek.vasut@gmail.com>,
        Tony Lindgren <tony@atomide.com>,
        Aaro Koskinen <aaro.koskinen@iki.fi>,
        linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org,
        linux-mtd@lists.infradead.org, linux-doc@vger.kernel.org,
        linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH v2 05/12] mtd: rawnand: ams-delta: use GPIO API for
 data read/write
Message-ID: <20180807190627.4340aade@bbrezillon>
In-Reply-To: <20180806222918.12644-6-jmkrzyszt@gmail.com>
References: <20180718235710.18242-1-jmkrzyszt@gmail.com>
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        <20180806222918.12644-6-jmkrzyszt@gmail.com>
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On Tue,  7 Aug 2018 00:29:11 +0200
Janusz Krzysztofik <jmkrzyszt@gmail.com> wrote:

> Don't readw()/writew() data directly from/to GPIO port which is under
> control of gpio-omap driver, use GPIO API instead.
> 
> Degrade of performance on Amstrad Delta is completely not acceptable.

Can we have numbers along with information about where the overhead is
when using gpiod_{get,set}_raw_array_value()?

> 
> The driver should work with any 8+-bit bidirectional GPIO port, not
> only OMAP.

That's cool!