From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f169.google.com ([209.85.192.169]:48807 "EHLO mail-pd0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751633Ab3G3Qeg (ORCPT ); Tue, 30 Jul 2013 12:34:36 -0400 Received: by mail-pd0-f169.google.com with SMTP id y11so1403473pdj.14 for ; Tue, 30 Jul 2013 09:34:35 -0700 (PDT) Date: Tue, 30 Jul 2013 09:34:41 -0700 From: Olof Johansson Subject: Re: [PATCH v2 1/4] mtd: nand: gpio: Determine bus width automatically Message-ID: <20130730163441.GB13634@quad.lixom.net> References: <1375182325-30003-1-git-send-email-shc_work@mail.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1375182325-30003-1-git-send-email-shc_work@mail.ru> Sender: devicetree-owner@vger.kernel.org To: Alexander Shiyan Cc: linux-mtd@lists.infradead.org, David Woodhouse , Artem Bityutskiy , Brian Norris , devicetree@vger.kernel.org, Rob Herring , Pawel Moll , Mark Rutland , Stephen Warren , Ian Campbell List-ID: On Tue, Jul 30, 2013 at 03:05:24PM +0400, Alexander Shiyan wrote: > This patch provide automatically determine of NAND bus width if > "bank-width" parameter is ommited. > Patch depends on "mtd: nand: fix NAND_BUSWIDTH_AUTO for x16 devices". > > Signed-off-by: Alexander Shiyan > --- > .../devicetree/bindings/mtd/gpio-control-nand.txt | 4 ++-- > drivers/mtd/nand/gpio.c | 15 ++++++++++----- > 2 files changed, 12 insertions(+), 7 deletions(-) > > diff --git a/Documentation/devicetree/bindings/mtd/gpio-control-nand.txt b/Documentation/devicetree/bindings/mtd/gpio-control-nand.txt > index 36ef07d..2ac14d8 100644 > --- a/Documentation/devicetree/bindings/mtd/gpio-control-nand.txt > +++ b/Documentation/devicetree/bindings/mtd/gpio-control-nand.txt > @@ -15,8 +15,8 @@ Required properties: > optional gpio and may be set to 0 if not present. > > Optional properties: > -- bank-width : Width (in bytes) of the device. If not present, the width > - defaults to 1 byte. > +- bank-width : Width (in bytes) of the device. If not present, the bus width > + of the device is determined automatically. > - chip-delay : chip dependent delay for transferring data from array to > read registers (tR). If not present then a default of 20us is used. > - gpio-control-nand,io-sync-reg : A 64-bit physical address for a read This would break backwards compatibility, something we're now starting to push back at. Instead what you can do is add a bank-width-auto property that, if present and bank-width being absent, will result in the automatic determination of bank width. -Olof