From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Brezillon Subject: Re: [RFC PATCH v2 05/12] mtd: rawnand: ams-delta: use GPIO API for data read/write Date: Tue, 7 Aug 2018 19:06:27 +0200 Message-ID: <20180807190627.4340aade@bbrezillon> References: <20180718235710.18242-1-jmkrzyszt@gmail.com> <20180806222918.12644-1-jmkrzyszt@gmail.com> <20180806222918.12644-6-jmkrzyszt@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180806222918.12644-6-jmkrzyszt@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Janusz Krzysztofik Cc: Linus Walleij , Jonathan Corbet , Miquel Raynal , Richard Weinberger , David Woodhouse , Brian Norris , Marek Vasut , Tony Lindgren , Aaro Koskinen , 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 List-Id: linux-gpio@vger.kernel.org On Tue, 7 Aug 2018 00:29:11 +0200 Janusz Krzysztofik 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!