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=-16.0 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 autolearn=unavailable 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 32C4CC4743C for ; Mon, 7 Jun 2021 09:31:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1A7CB611AB for ; Mon, 7 Jun 2021 09:31:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230287AbhFGJdI (ORCPT ); Mon, 7 Jun 2021 05:33:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:45098 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229436AbhFGJdH (ORCPT ); Mon, 7 Jun 2021 05:33:07 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0F992610A1; Mon, 7 Jun 2021 09:31:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1623058276; bh=LrBvHL3aolaWr2c2hTdDl2fLYXTXMYq/Ecg4VX6RQWQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=YfQUp1/pQra+W56MbgRlkpno1T22lOTw9m74WtDyVylyrNs/z6na/8M7dyt43yiE6 VP3ThltpOEN1PVkBsZfcXWwhU+ipr07pKfhKqCx21DCXnGsWAeYSPnjmTDRQesBnU3 NDhJiGnOlPHv5mrc8/gnx2g3zu0YMPMco7/vGx44= Date: Mon, 7 Jun 2021 11:31:14 +0200 From: Greg Kroah-Hartman To: Jiri Prchal Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Rob Herring , Christian Eggers , Arnd Bergmann Subject: Re: [PATCH v6 4/5] nvmem: eeprom: at25: export FRAM serial num Message-ID: References: <20210607082638.52409-1-jiri.prchal@aksignal.cz> <20210607082638.52409-5-jiri.prchal@aksignal.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210607082638.52409-5-jiri.prchal@aksignal.cz> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 07, 2021 at 10:26:37AM +0200, Jiri Prchal wrote: > This exports serial number of FRAM in sysfs file named "sernum". > Formatted in hex, each byte separated by space. > Example: > $ cat /sys/class/spi_master/spi0/spi0.0/sernum > 0000a43644f2ae6c > > Signed-off-by: Jiri Prchal > --- > v2: no change here > v3: resend and added more recipients > v4: resend > v5: reworked up on Greg comments: no spaces in string, sysfs done correctly > v6: no change here > --- > drivers/misc/eeprom/at25.c | 28 +++++++++++++++++++++++++++- > 1 file changed, 27 insertions(+), 1 deletion(-) > > diff --git a/drivers/misc/eeprom/at25.c b/drivers/misc/eeprom/at25.c > index 45a486994828..4e4fa8d3ba5d 100644 > --- a/drivers/misc/eeprom/at25.c > +++ b/drivers/misc/eeprom/at25.c > @@ -39,6 +39,7 @@ struct at25_data { > struct nvmem_config nvmem_config; > struct nvmem_device *nvmem; > int has_sernum; > + char *sernum; > }; > > #define AT25_WREN 0x06 /* latch the write enable */ > @@ -173,6 +174,25 @@ static int fm25_aux_read(struct at25_data *at25, char *buf, uint8_t command, > return status; > } > > +static ssize_t sernum_show(struct device *dev, struct device_attribute *attr, char *buf) > +{ > + struct at25_data *at25; > + int i; > + > + at25 = dev_get_drvdata(dev); > + for (i = FM25_SN_LEN - 1; i >= 0; i--) > + buf += sprintf(buf, "%02x", at25->sernum[i]); > + sprintf(buf, "\n"); Please use sysfs_emit() with the proper print modifier for an array of bytes in hex (I think there is one...) > + return (2 * FM25_SN_LEN + 1); > +} > +static DEVICE_ATTR(sernum, 0440, sernum_show, NULL); DEVICE_ATTR_RO() please. > + > +static struct attribute *sernum_attrs[] = { > + &dev_attr_sernum.attr, > + NULL, > +}; > +ATTRIBUTE_GROUPS(sernum); > + > static int at25_ee_write(void *priv, unsigned int off, void *val, size_t count) > { > struct at25_data *at25 = priv; > @@ -417,8 +437,13 @@ static int at25_probe(struct spi_device *spi) > else > at25->chip.flags |= EE_ADDR2; > > - if (id[8]) > + if (id[8]) { > at25->has_sernum = 1; > + at25->sernum = kzalloc(FM25_SN_LEN, GFP_KERNEL); Where do you free this memory? And why does it have to be 0 filled? thanks, greg k-h