From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751370AbaLERHR (ORCPT ); Fri, 5 Dec 2014 12:07:17 -0500 Received: from eusmtp01.atmel.com ([212.144.249.242]:61000 "EHLO eusmtp01.atmel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751183AbaLERHM (ORCPT ); Fri, 5 Dec 2014 12:07:12 -0500 Message-ID: <5481E63C.5020208@atmel.com> Date: Fri, 5 Dec 2014 18:07:08 +0100 From: Nicolas Ferre Organization: atmel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: Boris Brezillon , Brian Norris , , Josh Wu , Alexandre Belloni CC: David Woodhouse , Jean-Christophe Plagniol-Villard , Andrew Victor , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , "Kumar Gala" , , , Subject: Re: [PATCH 0/4] mtd: nand: atmel: Rework DT representation of NFC/NAND References: <1417732214-3292-1-git-send-email-boris.brezillon@free-electrons.com> In-Reply-To: <1417732214-3292-1-git-send-email-boris.brezillon@free-electrons.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 8bit X-Originating-IP: [10.161.30.18] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le 04/12/2014 23:30, Boris Brezillon a écrit : > Hello, > > While working on the EBI driver [1] I noticed that the relationship between > the NFC (NAND Flash Controller) and the NAND chip it is attached to would > make things harder to represent when moving the NAND node under the EBI bus > (another useless 'ranges' definition). > > Actually this representation might be even more problematic if one wants > decide to connect two NAND chips on his sama5 based board, because the NFC > node is a child of the NAND chip node, and thus can only be attached to a > single NAND chip. > > To address this problem the current series moves the NFC node outside of > the NAND chip device which then reference the NFC using the "atmel,nfc" > property. > > The series does not implement multi-chip support, but at least the new > representation should make it possible. > > Best Regards, > > Boris > > [1]https://lkml.org/lkml/2014/12/3/806 Boris, It sounds promising and for sure we have to think about a way to deal with SMC (EBI interface) and the NAND controller with its attributes (PMECC) or flavors (plain SMC or NFC). Let's consider this as a RFC and discuss how to deal with the DT modifications and the representation hierarchy all together. Thanks, bye. > Boris Brezillon (4): > mtd: nand: atmel: Rework driver to separate nfc and nand nodes > mtd: nand: atmel: Update DT documentation after splitting NFC and NAND > ARM: at91/dt: sama5: move NFC nodes outside of NAND nodes > ARM: at91/dt: sama5: move NAND nodes into board dts/dtsi > > .../devicetree/bindings/mtd/atmel-nand.txt | 46 +++++++------ > arch/arm/boot/dts/at91-sama5d3_xplained.dts | 18 ++++- > arch/arm/boot/dts/at91-sama5d4ek.dts | 16 ++++- > arch/arm/boot/dts/sama5d3.dtsi | 36 ++-------- > arch/arm/boot/dts/sama5d3xcm.dtsi | 18 ++++- > arch/arm/boot/dts/sama5d4.dtsi | 36 ++-------- > drivers/mtd/nand/atmel_nand.c | 76 +++++++++++++++++----- > 7 files changed, 149 insertions(+), 97 deletions(-) > -- Nicolas Ferre