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=-17.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 A46B8C433E2 for ; Mon, 22 Mar 2021 14:45:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5A8F9619A2 for ; Mon, 22 Mar 2021 14:45:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229987AbhCVOoe (ORCPT ); Mon, 22 Mar 2021 10:44:34 -0400 Received: from fllv0015.ext.ti.com ([198.47.19.141]:37758 "EHLO fllv0015.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229673AbhCVOoA (ORCPT ); Mon, 22 Mar 2021 10:44:00 -0400 Received: from lelv0266.itg.ti.com ([10.180.67.225]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id 12MEhmt1015180; Mon, 22 Mar 2021 09:43:48 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1616424228; bh=WJL8DAAbzAlsFa5GLWTVFiPVxPG+FuITJus6PMJQUpM=; h=Date:From:To:CC:Subject:References:In-Reply-To; b=Uoc8iS1nUOm9YioVY3+/k1OGyDhP8hLCLFh/wykFqtT/639CgjI/ITd2xgo3muAnS AcW6bYTXZ4vlNv4bJ8VZXP3suV/wKfrmkvS9dyFLEM2qgp1maesjVSL4WRl2oj9gvI pdsJ86mSzVGuxAEXKsmptlczDIWUKo1EIVU3uuzQ= Received: from DFLE115.ent.ti.com (dfle115.ent.ti.com [10.64.6.36]) by lelv0266.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 12MEhm2s058620 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 22 Mar 2021 09:43:48 -0500 Received: from DFLE109.ent.ti.com (10.64.6.30) by DFLE115.ent.ti.com (10.64.6.36) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Mon, 22 Mar 2021 09:43:48 -0500 Received: from lelv0326.itg.ti.com (10.180.67.84) by DFLE109.ent.ti.com (10.64.6.30) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2 via Frontend Transport; Mon, 22 Mar 2021 09:43:47 -0500 Received: from localhost (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0326.itg.ti.com (8.15.2/8.15.2) with ESMTP id 12MEhlu4019810; Mon, 22 Mar 2021 09:43:47 -0500 Date: Mon, 22 Mar 2021 20:13:46 +0530 From: Pratyush Yadav To: Michael Walle CC: , , Tudor Ambarus , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra Subject: Re: [PATCH 2/2] mtd: spi-nor: add initial sysfs support Message-ID: <20210322144344.4hys4zs57hnsjyjy@ti.com> References: <20210318092406.5340-1-michael@walle.cc> <20210318092406.5340-3-michael@walle.cc> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20210318092406.5340-3-michael@walle.cc> User-Agent: NeoMutt/20171215 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Michael, I have not worked with sysfs much so only giving this patch a quick overview. On 18/03/21 10:24AM, Michael Walle wrote: > Add support to show the name and JEDEC identifier as well as to dump the > SFDP table. Not all flashes list their SFDP table contents in their > datasheet. So having that is useful. It might also be helpful in bug > reports from users. > > The idea behind the sysfs module is also to have raw access to the SPI > NOR flash device registers, which can also be useful for debugging. Your current patch does not add this feature. Why do you think it is important enough to mention it? > > Signed-off-by: Michael Walle > --- > drivers/mtd/spi-nor/Makefile | 2 +- > drivers/mtd/spi-nor/core.c | 5 +++ > drivers/mtd/spi-nor/core.h | 3 ++ > drivers/mtd/spi-nor/sysfs.c | 86 ++++++++++++++++++++++++++++++++++++ > 4 files changed, 95 insertions(+), 1 deletion(-) > create mode 100644 drivers/mtd/spi-nor/sysfs.c > > diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile > index 653923896205..aff308f75987 100644 > --- a/drivers/mtd/spi-nor/Makefile > +++ b/drivers/mtd/spi-nor/Makefile > @@ -1,6 +1,6 @@ > # SPDX-License-Identifier: GPL-2.0 > > -spi-nor-objs := core.o sfdp.o > +spi-nor-objs := core.o sfdp.o sysfs.o > spi-nor-objs += atmel.o > spi-nor-objs += catalyst.o > spi-nor-objs += eon.o > diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c > index 4a315cb1c4db..2eaf4ba8c0f3 100644 > --- a/drivers/mtd/spi-nor/core.c > +++ b/drivers/mtd/spi-nor/core.c > @@ -3707,6 +3707,10 @@ static int spi_nor_probe(struct spi_mem *spimem) > if (ret) > return ret; > > + ret = spi_nor_sysfs_create(nor); > + if (ret) > + return ret; > + > return mtd_device_register(&nor->mtd, data ? data->parts : NULL, > data ? data->nr_parts : 0); > } > @@ -3716,6 +3720,7 @@ static int spi_nor_remove(struct spi_mem *spimem) > struct spi_nor *nor = spi_mem_get_drvdata(spimem); > > spi_nor_restore(nor); > + spi_nor_sysfs_remove(nor); > > /* Clean up MTD stuff. */ > return mtd_device_unregister(&nor->mtd); > diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h > index 668f22011b1d..dd592f7b62d1 100644 > --- a/drivers/mtd/spi-nor/core.h > +++ b/drivers/mtd/spi-nor/core.h > @@ -488,4 +488,7 @@ static struct spi_nor __maybe_unused *mtd_to_spi_nor(struct mtd_info *mtd) > return mtd->priv; > } > > +int spi_nor_sysfs_create(struct spi_nor *nor); > +void spi_nor_sysfs_remove(struct spi_nor *nor); > + > #endif /* __LINUX_MTD_SPI_NOR_INTERNAL_H */ > diff --git a/drivers/mtd/spi-nor/sysfs.c b/drivers/mtd/spi-nor/sysfs.c > new file mode 100644 > index 000000000000..0de031e246c5 > --- /dev/null > +++ b/drivers/mtd/spi-nor/sysfs.c > @@ -0,0 +1,86 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +#include > +#include > +#include > +#include > + > +#include "core.h" > + > +static ssize_t name_show(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + struct spi_device *spi = to_spi_device(dev); > + struct spi_mem *spimem = spi_get_drvdata(spi); > + struct spi_nor *nor = spi_mem_get_drvdata(spimem); > + > + return sprintf(buf, "%s\n", nor->info->name); > +} > +static DEVICE_ATTR_RO(name); > + > +static ssize_t jedec_id_show(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + struct spi_device *spi = to_spi_device(dev); > + struct spi_mem *spimem = spi_get_drvdata(spi); > + struct spi_nor *nor = spi_mem_get_drvdata(spimem); > + > + return sprintf(buf, "%*phN\n", nor->info->id_len, nor->info->id); > +} > +static DEVICE_ATTR_RO(jedec_id); > + > +static struct attribute *spi_nor_sysfs_entries[] = { > + &dev_attr_name.attr, > + &dev_attr_jedec_id.attr, > + NULL > +}; > + > +static ssize_t sfdp_read(struct file *filp, struct kobject *kobj, > + struct bin_attribute *bin_attr, char *buf, > + loff_t off, size_t count) > +{ > + struct spi_device *spi = to_spi_device(kobj_to_dev(kobj)); > + struct spi_mem *spimem = spi_get_drvdata(spi); > + struct spi_nor *nor = spi_mem_get_drvdata(spimem); > + struct sfdp *sfdp = nor->sfdp; > + size_t sfdp_size = sfdp->num_dwords * sizeof(*sfdp->dwords); Is a NULL check needed here? If the flash does not have a SFDP table nor->sfdp will be NULL. > + > + return memory_read_from_buffer(buf, count, &off, nor->sfdp->dwords, > + sfdp_size); > +} > +static BIN_ATTR_RO(sfdp, PAGE_SIZE); > + > +static struct bin_attribute *spi_nor_sysfs_bin_entries[] = { > + &bin_attr_sfdp, > + NULL > +}; > + > +static umode_t spi_nor_sysfs_is_bin_visible(struct kobject *kobj, > + struct bin_attribute *attr, int n) > +{ > + struct spi_device *spi = to_spi_device(kobj_to_dev(kobj)); > + struct spi_mem *spimem = spi_get_drvdata(spi); > + struct spi_nor *nor = spi_mem_get_drvdata(spimem); > + > + if (attr == &bin_attr_sfdp && nor->sfdp) > + return 0444; > + > + return 0; > +} > + > +static struct attribute_group spi_nor_sysfs_attr_group = { > + .name = NULL, > + .is_bin_visible = spi_nor_sysfs_is_bin_visible, > + .attrs = spi_nor_sysfs_entries, > + .bin_attrs = spi_nor_sysfs_bin_entries, > +}; > + > +int spi_nor_sysfs_create(struct spi_nor *nor) > +{ > + return sysfs_create_group(&nor->dev->kobj, &spi_nor_sysfs_attr_group); > +} > + > +void spi_nor_sysfs_remove(struct spi_nor *nor) > +{ > + sysfs_remove_group(&nor->dev->kobj, &spi_nor_sysfs_attr_group); > +} > -- > 2.20.1 > Rest of it looks good to me. -- Regards, Pratyush Yadav Texas Instruments Inc.