Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936401AbdCJMwz (ORCPT ); Fri, 10 Mar 2017 07:52:55 -0500 Received: from mail-wm0-f66.google.com ([74.125.82.66]:36833 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933901AbdCJMwv (ORCPT ); Fri, 10 Mar 2017 07:52:51 -0500 Subject: Re: [v2, 4/4] dt-bindings: mtd: Add Octal SPI support to Cadence QSPI. To: Artur Jedrysek , "devicetree@vger.kernel.org" , "linux-mtd@lists.infradead.org" References: <1488959932-6657-1-git-send-email-jartur@cadence.com> <1488960326-13858-1-git-send-email-jartur@cadence.com> <132a4818-11d1-263f-aae4-bac4e76c14c8@gmail.com> Cc: "linux-kernel@vger.kernel.org" , Cyrille Pitchen , David Woodhouse , Brian Norris , Boris Brezillon , Richard Weinberger , Rob Herring , Mark Rutland From: Marek Vasut Message-ID: <7d303436-77cf-fb11-30b6-c59014950ae6@gmail.com> Date: Fri, 10 Mar 2017 13:52:31 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Icedove/45.4.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2700 Lines: 73 On 03/10/2017 01:03 PM, Artur Jedrysek wrote: > >> From: Marek Vasut [mailto:marek.vasut@gmail.com] >> Sent: 10 March 2017 04:39 >> On 03/08/2017 09:05 AM, Artur Jedrysek wrote: >>> This patch updates Cadence QSPI Device Tree documentation to include >>> information about new compatible used to indicate, whether or not >>> Octal SPI transfers are supported by the device. >>> >>> Signed-off-by: Artur Jedrysek >>> --- >>> Changelog: >>> v2: Use new compatible, instead of boolean property, to indicate >>> Octal SPI support. >>> --- >>> Documentation/devicetree/bindings/mtd/cadence-quadspi.txt | 4 +++- >>> 1 file changed, 3 insertions(+), 1 deletion(-) >>> >>> diff --git a/Documentation/devicetree/bindings/mtd/cadence-quadspi.txt >> b/Documentation/devicetree/bindings/mtd/cadence-quadspi.txt >>> index f248056..41d1e98 100644 >>> --- a/Documentation/devicetree/bindings/mtd/cadence-quadspi.txt >>> +++ b/Documentation/devicetree/bindings/mtd/cadence-quadspi.txt >>> @@ -1,7 +1,9 @@ >>> * Cadence Quad SPI controller >>> >>> Required properties: >>> -- compatible : Should be "cdns,qspi-nor". >>> +- compatible : Should be "cdns,{qspi|ospi}-nor". >> >> Please explicitly list all compatibles , ie. >> Should be "cdns,qspi-nor" or "cdns,ospi-nor". >> > > Two possible options are also explicitly listed right below. I did that > in the way it was done in other driver for Cadence IP: > /Documentation/devicetree/bindings/net/macb.txt > Should I remove all of that and replace it with both options, separated > by an "or" word? Wait for Rob to confirm. >> But I think the ospi is backward compatible with qspi, right ? So the >> binding for ospi should list both, ie. >> compatible = "cdns,ospi-nor", "cdns,qspi-nor"; >> > > Yes, the ospi is backwards compatible with qspi. However, the sole point > of introducing new compatible was to differentiate between them (which > was previously done using a boolean flag, but that was criticized). > Listing both bindings for ospi would only help for kernels not > containing driver update being subject of this patch series, as both > ospi and qspi are handled by the same driver - just with a slight > difference. I apologize if I got something wrong here. You got it right, I was just curious about the compatibility. >>> + Use "cdns,qspi-nor" for Quad SPI controller. >>> + Use "cdns,ospi-nor" for Octal SPI controller. >>> - reg : Contains two entries, each of which is a tuple consisting of a >>> physical address and length. The first entry is the address and >>> length of the controller register set. The second entry is the >>> >> >> >> -- >> Best regards, >> Marek Vasut -- Best regards, Marek Vasut