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=-8.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,USER_AGENT_MUTT 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 DF2A9C43381 for ; Thu, 21 Feb 2019 22:14:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9CC692083B for ; Thu, 21 Feb 2019 22:14:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="vxrhw+Zh" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726989AbfBUWOJ (ORCPT ); Thu, 21 Feb 2019 17:14:09 -0500 Received: from perceval.ideasonboard.com ([213.167.242.64]:48418 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726191AbfBUWOI (ORCPT ); Thu, 21 Feb 2019 17:14:08 -0500 Received: from pendragon.ideasonboard.com (81-175-216-236.bb.dnainternet.fi [81.175.216.236]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 33081255; Thu, 21 Feb 2019 23:14:04 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1550787244; bh=PUlX7KVzDkkm3YAHbyDB0OiEtsMPiA6tO/4qL0MAltU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=vxrhw+ZhoPfflT9E8gIcnxX78jJQ2puCwrQRgb3cL+SePyju6FzCMAxjdUS0mZAnR gYViu1qbbOR5cDyIQ5jpcvox2g0FH8SvCJ686lTA4lCA4StjiIzVg6kmYFFFyq9D2B 5WF/B8326YtbYIp3hbsFB8VojWBrEArXVj8jfb5s= Date: Fri, 22 Feb 2019 00:13:59 +0200 From: Laurent Pinchart To: Bjorn Andersson Cc: Vaishali Thakkar , andy.gross@linaro.org, david.brown@linaro.org, gregkh@linuxfoundation.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, rafael@kernel.org, vkoul@kernel.org Subject: Re: [PATCH v2 3/5] soc: qcom: socinfo: Expose custom attributes Message-ID: <20190221221359.GD3485@pendragon.ideasonboard.com> References: <20190220045829.6852-1-vaishali.thakkar@linaro.org> <20190221121841.GA32108@pendragon.ideasonboard.com> <20190221155742.GD2122@tuxbook-pro> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20190221155742.GD2122@tuxbook-pro> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Bjorn, On Thu, Feb 21, 2019 at 07:57:42AM -0800, Bjorn Andersson wrote: > On Thu 21 Feb 04:18 PST 2019, Laurent Pinchart wrote: > > > Hi Vaishali, > > > > Thank you for the patch. > > > > On Wed, Feb 20, 2019 at 10:28:29AM +0530, Vaishali Thakkar wrote: > > > The Qualcomm socinfo provides a number of additional attributes, > > > add these to the socinfo driver and expose them via debugfs > > > functionality. > > > > What is the use case for these attributes ? I fear they will be used in > > production systems, and that would require debugfs in production, which > > isn't a good idea. If you need to expose those attributes for anything > > else than debugging then we need a proper API, likely sysfs-based. > > The use case of these attributes, beyond development/debugging, are > unfortunately somewhat unknown and is the reason why they where moved to > debugfs from the earlier attempts to upstream this. > > I think the production requirements at hand prohibits debugfs to be > present, so attributes that are required beyond development/debugging > purposes would have to be migrated out to sysfs - but the idea here is > that such migration would have come with the missing motivation to add > them there today. If the use case is just debug/development, would it be enough to print this information in the kernel log at boot time ? I may be a bit paranoid, but I always worry about API abuse :-( > > > Signed-off-by: Vaishali Thakkar > > > --- > > > Changes since v1: > > > - Remove unnecessary debugfs dir creation check > > > - Align ifdefs to left > > > - Fix function signatures for debugfs init/exit > > > --- > > > drivers/soc/qcom/socinfo.c | 198 +++++++++++++++++++++++++++++++++++++ > > > 1 file changed, 198 insertions(+) > > > > > > diff --git a/drivers/soc/qcom/socinfo.c b/drivers/soc/qcom/socinfo.c > > > index 02078049fac7..5f4bef216ae1 100644 > > > --- a/drivers/soc/qcom/socinfo.c > > > +++ b/drivers/soc/qcom/socinfo.c > > > @@ -4,6 +4,7 @@ > > > * Copyright (c) 2017-2019, Linaro Ltd. > > > */ > > > > > > +#include > > > #include > > > #include > > > #include > > > @@ -29,6 +30,28 @@ > > > */ > > > #define SMEM_HW_SW_BUILD_ID 137 > > > > > > +#ifdef CONFIG_DEBUG_FS > > > +/* pmic model info */ > > > +static const char *const pmic_model[] = { > > > + [0] = "Unknown PMIC model", > > > + [9] = "PM8994", > > > + [11] = "PM8916", > > > + [13] = "PM8058", > > > + [14] = "PM8028", > > > + [15] = "PM8901", > > > + [16] = "PM8027", > > > + [17] = "ISL9519", > > > + [18] = "PM8921", > > > + [19] = "PM8018", > > > + [20] = "PM8015", > > > + [21] = "PM8014", > > > + [22] = "PM8821", > > > + [23] = "PM8038", > > > + [24] = "PM8922", > > > + [25] = "PM8917", > > > +}; > > > +#endif /* CONFIG_DEBUG_FS */ > > > + > > > /* Socinfo SMEM item structure */ > > > struct socinfo { > > > __le32 fmt; > > > @@ -70,6 +93,10 @@ struct socinfo { > > > struct qcom_socinfo { > > > struct soc_device *soc_dev; > > > struct soc_device_attribute attr; > > > +#ifdef CONFIG_DEBUG_FS > > > + struct dentry *dbg_root; > > > +#endif /* CONFIG_DEBUG_FS */ > > > + struct socinfo *socinfo; > > > }; > > > > > > struct soc_of_id { > > > @@ -133,6 +160,171 @@ static const char *socinfo_machine(struct device *dev, unsigned int id) > > > return NULL; > > > } > > > > > > +#ifdef CONFIG_DEBUG_FS > > > + > > > +#define UINT_SHOW(name, attr) \ > > > +static int qcom_show_##name(struct seq_file *seq, void *p) \ > > > +{ \ > > > + struct socinfo *socinfo = seq->private; \ > > > + seq_printf(seq, "%u\n", le32_to_cpu(socinfo->attr)); \ > > > + return 0; \ > > > +} \ > > > +static int qcom_open_##name(struct inode *inode, struct file *file) \ > > > +{ \ > > > + return single_open(file, qcom_show_##name, inode->i_private); \ > > > +} \ > > > + \ > > > +static const struct file_operations qcom_ ##name## _ops = { \ > > > + .open = qcom_open_##name, \ > > > + .read = seq_read, \ > > > + .llseek = seq_lseek, \ > > > + .release = single_release, \ > > > +} > > > + > > > +#define DEBUGFS_UINT_ADD(name) \ > > > + debugfs_create_file(__stringify(name), 0400, \ > > > + qcom_socinfo->dbg_root, \ > > > + qcom_socinfo->socinfo, &qcom_ ##name## _ops) > > > + > > > +#define HEX_SHOW(name, attr) \ > > > +static int qcom_show_##name(struct seq_file *seq, void *p) \ > > > +{ \ > > > + struct socinfo *socinfo = seq->private; \ > > > + seq_printf(seq, "0x%x\n", le32_to_cpu(socinfo->attr)); \ > > > + return 0; \ > > > +} \ > > > +static int qcom_open_##name(struct inode *inode, struct file *file) \ > > > +{ \ > > > + return single_open(file, qcom_show_##name, inode->i_private); \ > > > +} \ > > > + \ > > > +static const struct file_operations qcom_ ##name## _ops = { \ > > > + .open = qcom_open_##name, \ > > > + .read = seq_read, \ > > > + .llseek = seq_lseek, \ > > > + .release = single_release, \ > > > +} > > > + > > > +#define DEBUGFS_HEX_ADD(name) \ > > > + debugfs_create_file(__stringify(name), 0400, \ > > > + qcom_socinfo->dbg_root, \ > > > + qcom_socinfo->socinfo, &qcom_ ##name## _ops) > > > + > > > + > > > +#define QCOM_OPEN(name, _func) \ > > > +static int qcom_open_##name(struct inode *inode, struct file *file) \ > > > +{ \ > > > + return single_open(file, _func, inode->i_private); \ > > > +} \ > > > + \ > > > +static const struct file_operations qcom_ ##name## _ops = { \ > > > + .open = qcom_open_##name, \ > > > + .read = seq_read, \ > > > + .llseek = seq_lseek, \ > > > + .release = single_release, \ > > > +} > > > + > > > +#define DEBUGFS_ADD(name) \ > > > + debugfs_create_file(__stringify(name), 0400, \ > > > + qcom_socinfo->dbg_root, \ > > > + qcom_socinfo->socinfo, &qcom_ ##name## _ops) > > > + > > > + > > > +static int qcom_show_build_id(struct seq_file *seq, void *p) > > > +{ > > > + struct socinfo *socinfo = seq->private; > > > + > > > + seq_printf(seq, "%s\n", socinfo->build_id); > > > + > > > + return 0; > > > +} > > > + > > > +static int qcom_show_accessory_chip(struct seq_file *seq, void *p) > > > +{ > > > + struct socinfo *socinfo = seq->private; > > > + > > > + seq_printf(seq, "%d\n", le32_to_cpu(socinfo->accessory_chip)); > > > + > > > + return 0; > > > +} > > > + > > > +static int qcom_show_platform_subtype(struct seq_file *seq, void *p) > > > +{ > > > + struct socinfo *socinfo = seq->private; > > > + int subtype = le32_to_cpu(socinfo->hw_plat_subtype); > > > + > > > + if (subtype < 0) > > > + return -EINVAL; > > > + > > > + seq_printf(seq, "%u\n", subtype); > > > + > > > + return 0; > > > +} > > > + > > > +static int qcom_show_pmic_model(struct seq_file *seq, void *p) > > > +{ > > > + struct socinfo *socinfo = seq->private; > > > + int model = SOCINFO_MINOR(le32_to_cpu(socinfo->pmic_model)); > > > + > > > + if (model < 0) > > > + return -EINVAL; > > > + > > > + seq_printf(seq, "%s\n", pmic_model[model]); > > > + > > > + return 0; > > > +} > > > + > > > +static int qcom_show_pmic_die_revision(struct seq_file *seq, void *p) > > > +{ > > > + struct socinfo *socinfo = seq->private; > > > + > > > + seq_printf(seq, "%u.%u\n", > > > + SOCINFO_MAJOR(le32_to_cpu(socinfo->pmic_die_rev)), > > > + SOCINFO_MINOR(le32_to_cpu(socinfo->pmic_die_rev))); > > > + > > > + return 0; > > > +} > > > + > > > +UINT_SHOW(raw_version, raw_ver); > > > +UINT_SHOW(hardware_platform, hw_plat); > > > +UINT_SHOW(platform_version, plat_ver); > > > +UINT_SHOW(foundry_id, foundry_id); > > > +HEX_SHOW(chip_family, chip_family); > > > +HEX_SHOW(raw_device_family, raw_device_family); > > > +HEX_SHOW(raw_device_number, raw_device_num); > > > +QCOM_OPEN(build_id, qcom_show_build_id); > > > +QCOM_OPEN(accessory_chip, qcom_show_accessory_chip); > > > +QCOM_OPEN(pmic_model, qcom_show_pmic_model); > > > +QCOM_OPEN(platform_subtype, qcom_show_platform_subtype); > > > +QCOM_OPEN(pmic_die_revision, qcom_show_pmic_die_revision); > > > + > > > +static void socinfo_debugfs_init(struct qcom_socinfo *qcom_socinfo) > > > +{ > > > + qcom_socinfo->dbg_root = debugfs_create_dir("qcom_socinfo", NULL); > > > + > > > + DEBUGFS_UINT_ADD(raw_version); > > > + DEBUGFS_UINT_ADD(hardware_platform); > > > + DEBUGFS_UINT_ADD(platform_version); > > > + DEBUGFS_UINT_ADD(foundry_id); > > > + DEBUGFS_HEX_ADD(chip_family); > > > + DEBUGFS_HEX_ADD(raw_device_family); > > > + DEBUGFS_HEX_ADD(raw_device_number); > > > + DEBUGFS_ADD(build_id); > > > + DEBUGFS_ADD(accessory_chip); > > > + DEBUGFS_ADD(pmic_model); > > > + DEBUGFS_ADD(platform_subtype); > > > + DEBUGFS_ADD(pmic_die_revision); > > > +} > > > + > > > +static void socinfo_debugfs_exit(struct qcom_socinfo *qcom_socinfo) > > > +{ > > > + debugfs_remove_recursive(qcom_socinfo->dbg_root); > > > +} > > > +#else > > > +static void socinfo_debugfs_init(struct qcom_socinfo *qcom_socinfo) { return 0; } > > > +static void socinfo_debugfs_exit(struct qcom_socinfo *qcom_socinfo) { } > > > +#endif /* CONFIG_DEBUG_FS */ > > > + > > > static int qcom_socinfo_probe(struct platform_device *pdev) > > > { > > > struct qcom_socinfo *qs; > > > @@ -165,6 +357,10 @@ static int qcom_socinfo_probe(struct platform_device *pdev) > > > if (IS_ERR(qs->soc_dev)) > > > return PTR_ERR(qs->soc_dev); > > > > > > + qs->socinfo = info; > > > + > > > + socinfo_debugfs_init(qs); > > > + > > > /* Feed the soc specific unique data into entropy pool */ > > > add_device_randomness(info, item_size); > > > > > > @@ -179,6 +375,8 @@ static int qcom_socinfo_remove(struct platform_device *pdev) > > > > > > soc_device_unregister(qs->soc_dev); > > > > > > + socinfo_debugfs_exit(qs); > > > + > > > return 0; > > > } > > > -- Regards, Laurent Pinchart