From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7974AC54FD0 for ; Mon, 27 Apr 2020 14:22:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4E87F206B9 for ; Mon, 27 Apr 2020 14:22:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728018AbgD0OWc convert rfc822-to-8bit (ORCPT ); Mon, 27 Apr 2020 10:22:32 -0400 Received: from relay9-d.mail.gandi.net ([217.70.183.199]:49261 "EHLO relay9-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727073AbgD0OWc (ORCPT ); Mon, 27 Apr 2020 10:22:32 -0400 X-Originating-IP: 91.224.148.103 Received: from xps13 (unknown [91.224.148.103]) (Authenticated sender: miquel.raynal@bootlin.com) by relay9-d.mail.gandi.net (Postfix) with ESMTPSA id AB04AFF810; Mon, 27 Apr 2020 14:22:23 +0000 (UTC) Date: Mon, 27 Apr 2020 16:22:22 +0200 From: Miquel Raynal To: Ricardo Ribalda Delgado Cc: Richard Weinberger , Vignesh Raghavendra , linux-mtd@lists.infradead.org, LKML , Boris Brezillon , Tudor Ambarus Subject: Re: [PATCH v2] mtd: Fix mtd not the same name not registered if nvmem Message-ID: <20200427162222.1c2b2c85@xps13> In-Reply-To: References: <20200401100240.445447-1-ribalda@kernel.org> <20200402065953.9974-1-ribalda@kernel.org> Organization: Bootlin X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Ricardo, Ricardo Ribalda Delgado wrote on Tue, 14 Apr 2020 15:47:23 +0200: > Ping? > > On Thu, Apr 2, 2020 at 8:59 AM Ricardo Ribalda Delgado > wrote: > > > > When the nvmem framework is enabled, a nvmem device is created per mtd > > device/partition. > > > > It is not uncommon that a device can have multiple mtd devices with > > partitions that have the same name. Eg, when there DT overlay is allowed > > and the same device with mtd is attached twice. > > > > Under that circumstances, the mtd fails to register due to a name > > duplication on the nvmem framework. > > > > With this patch we add a _1, _2, _X to the subsequent names if there is > > a collition, and throw a warning, instead of not starting the mtd > > device. > > > > [ 8.948991] sysfs: cannot create duplicate filename '/bus/nvmem/devices/Production Data' > > [ 8.948992] CPU: 7 PID: 246 Comm: systemd-udevd Not tainted 5.5.0-qtec-standard #13 > > [ 8.948993] Hardware name: AMD Dibbler/Dibbler, BIOS 05.22.04.0019 10/26/2019 > > [ 8.948994] Call Trace: > > [ 8.948996] dump_stack+0x50/0x70 > > [ 8.948998] sysfs_warn_dup.cold+0x17/0x2d > > [ 8.949000] sysfs_do_create_link_sd.isra.0+0xc2/0xd0 > > [ 8.949002] bus_add_device+0x74/0x140 > > [ 8.949004] device_add+0x34b/0x850 > > [ 8.949006] nvmem_register.part.0+0x1bf/0x640 > > ... > > [ 8.948926] mtd mtd8: Failed to register NVMEM device > > > > Signed-off-by: Ricardo Ribalda Delgado Thanks for proposing this change. Indeed we are aware of the problem and the best solution that we could come up with was to create an additional "unique_name" field to the mtd_info structure. This new field would have the form: [] The separator might be '~' (but I am completely open on that), and that would give for instance: my-controller~my-device~my-part~mysub-part Then, you might use this mtd->unique_name instead of mtd->name. Would you give this logic a try? Thanks, Miquèl