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=-7.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED 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 6803FC04AB6 for ; Mon, 3 Jun 2019 07:21:11 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3B00827C95 for ; Mon, 3 Jun 2019 07:21:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="solyu5RI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3B00827C95 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=collabora.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=BwEf/CcrnZZiLY4fURbEICELhoXal2G9eyI98xeNM54=; b=solyu5RIim3eOA fU1tKiuf1H/D+crz13DOF52PRQ2dJ+nLpTFxiS17wD9DqdtyEImGzc1e4SLmVLohA1iZKISkiQP3c M8nqeKpgWNMLciPDwCn29aZDaPQNXlisHJoQO6Wc9lIj0MEA5IJMWhT+id6FJxMqILY7rlTcnRV3f HE+p5c6Kb4ahSbIBN/3Ui+dXQWkemHrA4w7l1m5DdLPQVh14RC0oz/++CYh/GumbcbXACuO8kL0Tj tHyLzBG0XtRtuIYIy9gg01M3Zy7qNsv78G52hhub0Dsk5mdHQjH9IJ60kjQXdoUk23aOESCqZqCzB aJzB/hztMHlr2ZD5FZcw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hXhHI-0007Cx-KJ; Mon, 03 Jun 2019 07:21:08 +0000 Received: from bhuna.collabora.co.uk ([46.235.227.227]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hXhHE-0007BU-D7 for linux-mtd@lists.infradead.org; Mon, 03 Jun 2019 07:21:07 +0000 Received: from localhost (unknown [IPv6:2a01:e0a:2c:6930:5cf4:84a1:2763:fe0d]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: bbrezillon) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 830CB26D296; Mon, 3 Jun 2019 08:20:59 +0100 (BST) Date: Mon, 3 Jun 2019 09:20:56 +0200 From: Boris Brezillon To: Zhuohao Lee Subject: Re: [PATCH v5 1/2] mtd: mtdcore: add debugfs nodes for querying the flash name and id Message-ID: <20190603092056.34f136d0@collabora.com> In-Reply-To: <20190603031451.60749-1-zhuohao@chromium.org> References: <20190603031451.60749-1-zhuohao@chromium.org> Organization: Collabora X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190603_002104_700719_E57748ED X-CRM114-Status: GOOD ( 25.77 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: drinkcat@chromium.org, bbrezillon@kernel.org, richard@nod.at, briannorris@chromium.org, marek.vasut@gmail.com, linux-mtd@lists.infradead.org, computersforpeace@gmail.com, dwmw2@infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org On Mon, 3 Jun 2019 11:14:50 +0800 Zhuohao Lee wrote: > Currently, we don't have vfs nodes for querying the underlying flash name > and flash id. This information is important especially when we want to > know the flash detail of the defective system. In order to support the > query, we add mtd_debugfs_populate() to create two debugfs nodes > (ie. partname and partid). The upper driver can assign the pointer to > partname and partid before calling mtd_device_register(). > > Signed-off-by: Zhuohao Lee > --- > Changes in V5: > - Move debugfs_create_dir() to mtd_debugfs_populate() > - Previous discussion: https://patchwork.ozlabs.org/patch/1107810/ > Changes in V4: > - Separate the change to two patches. The first patch is adding the general > handling for the partname and partid in the mtdcore.c. The second patch > is enabling the two debugfs nodes for spi-nor. > - Previous discussion: https://patchwork.ozlabs.org/patch/1097377/ > Changes in v3: > - Add partname and partid to mtd.h and create debugfs inside mtdcore.c > - Previous discussion: https://patchwork.ozlabs.org/patch/1095731/ > Changes in v2: > - Change to use debugfs to output flash name and id > - Previous discussion: https://patchwork.ozlabs.org/patch/1067763/ > --- > drivers/mtd/mtdcore.c | 88 ++++++++++++++++++++++++++++++++++++----- > include/linux/mtd/mtd.h | 4 ++ > 2 files changed, 83 insertions(+), 9 deletions(-) > > diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c > index 3ef01baef9b6..b1911c21eb1a 100644 > --- a/drivers/mtd/mtdcore.c > +++ b/drivers/mtd/mtdcore.c > @@ -357,6 +357,84 @@ static const struct device_type mtd_devtype = { > .release = mtd_release, > }; > > +static int mtd_partid_show(struct seq_file *s, void *p) > +{ > + struct mtd_info *mtd = s->private; > + > + if (!mtd->dbg.partid) > + return 0; > + > + seq_printf(s, "%s\n", mtd->dbg.partid); > + > + return 0; > +} > + > +static int mtd_partid_debugfs_open(struct inode *inode, struct file *file) > +{ > + return single_open(file, mtd_partid_show, inode->i_private); > +} > + > +static const struct file_operations mtd_partid_debug_fops = { > + .open = mtd_partid_debugfs_open, > + .read = seq_read, > + .llseek = seq_lseek, > + .release = single_release, > +}; > + > +static int mtd_partname_show(struct seq_file *s, void *p) > +{ > + struct mtd_info *mtd = s->private; > + > + if (!mtd->dbg.partname) > + return 0; > + > + seq_printf(s, "%s\n", mtd->dbg.partname); > + > + return 0; > +} > + > +static int mtd_partname_debugfs_open(struct inode *inode, struct file *file) > +{ > + return single_open(file, mtd_partname_show, inode->i_private); > +} > + > +static const struct file_operations mtd_partname_debug_fops = { > + .open = mtd_partname_debugfs_open, > + .read = seq_read, > + .llseek = seq_lseek, > + .release = single_release, > +}; > + > +static struct dentry *dfs_dir_mtd; > + > +static void mtd_debugfs_populate(struct mtd_info *mtd) > +{ > + struct device *dev = &mtd->dev; > + struct dentry *root, *dent; > + > + if (IS_ERR_OR_NULL(dfs_dir_mtd)) > + return; > + > + root = mtd->dbg.dfs_dir = debugfs_create_dir(dev_name(dev), > + dfs_dir_mtd); > + if (IS_ERR_OR_NULL(root)) { > + pr_debug("mtd device %s won't show data in debugfs\n", > + dev_name(dev)); > + return; > + } > + > + dent = debugfs_create_file("partid", S_IRUSR, root, mtd, > + &mtd_partid_debug_fops); > + if (IS_ERR_OR_NULL(dent)) { > + pr_err("cannot create debugfs entry for partid\n"); > + return; > + } > + dent = debugfs_create_file("partname", S_IRUSR, root, mtd, > + &mtd_partname_debug_fops); > + if (IS_ERR_OR_NULL(dent)) > + pr_err("cannot create debugfs entry for partname\n"); I wonder if it's not better to create those files only when mtd->dbg.part{name,id} != NULL. This way you could get rid of the if (!mtd->dbg.part{name,id}) test in the show funcs, and most importantly, the user would know when this fields are not present without having to read the file and test for an empty string. > +} > + > #ifndef CONFIG_MMU > unsigned mtd_mmap_capabilities(struct mtd_info *mtd) > { > @@ -534,8 +612,6 @@ static int mtd_nvmem_add(struct mtd_info *mtd) > return 0; > } > > -static struct dentry *dfs_dir_mtd; > - > /** > * add_mtd_device - register an MTD device > * @mtd: pointer to new MTD device info structure > @@ -621,13 +697,7 @@ int add_mtd_device(struct mtd_info *mtd) > if (error) > goto fail_nvmem_add; > > - if (!IS_ERR_OR_NULL(dfs_dir_mtd)) { > - mtd->dbg.dfs_dir = debugfs_create_dir(dev_name(&mtd->dev), dfs_dir_mtd); > - if (IS_ERR_OR_NULL(mtd->dbg.dfs_dir)) { > - pr_debug("mtd device %s won't show data in debugfs\n", > - dev_name(&mtd->dev)); > - } > - } > + mtd_debugfs_populate(mtd); > > device_create(&mtd_class, mtd->dev.parent, MTD_DEVT(i) + 1, NULL, > "mtd%dro", i); > diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h > index 677768b21a1d..c20f53c77899 100644 > --- a/include/linux/mtd/mtd.h > +++ b/include/linux/mtd/mtd.h > @@ -203,6 +203,10 @@ struct module; /* only needed for owner field in mtd_info */ > */ > struct mtd_debug_info { > struct dentry *dfs_dir; > + > + /* debugfs stuff starts here */ This comment is no longer valid: the whole struct contains debugfs stuff :P. > + const char *partname; > + const char *partid; > }; > > struct mtd_info { ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/