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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 59787C33CB3 for ; Tue, 28 Jan 2020 11:56:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3079624687 for ; Tue, 28 Jan 2020 11:56:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580212594; bh=cbY4qrepDwIPYuuvBAb/JcVe9z3yv1nJQYMwmA5VtU4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=mdiM+bl54C0/SxGPwlj082pKeAxSycwJgcjgVHA/xnduzD9kxmVKw5HzoLm60cIGw oo25BGdrmb7nNMIetOeXmNgrlz851sazJ8dbMWOfJhnkz5t+DPj0qligOXLjKGIlGn dwtHKVtJI1m0FAaDqW2Ahqk6Fy/7MxSbXgFi5KzU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726067AbgA1L4d (ORCPT ); Tue, 28 Jan 2020 06:56:33 -0500 Received: from mail.kernel.org ([198.145.29.99]:42900 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725903AbgA1L4d (ORCPT ); Tue, 28 Jan 2020 06:56:33 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A023D2173E; Tue, 28 Jan 2020 11:56:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580212592; bh=cbY4qrepDwIPYuuvBAb/JcVe9z3yv1nJQYMwmA5VtU4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=viTDkRB3SuwFFXB0GKABOuQzunieTBI6/i9ObGuRtbdMsW2YLYdo10WN1QWug2Ejt yCyWEfx56KdFPt/iQ9o2i4YX7AfK0mhJnQbvbvuFN9vD/ZsIPz2VTO9H+vDKMrose5 OUbGbV9VeIck5belq6/xIRFawGDNRKhGZsAAfFms= Date: Tue, 28 Jan 2020 12:56:29 +0100 From: Greg KH To: John Garry Cc: rjw@rjwysocki.net, lenb@kernel.org, jeremy.linton@arm.com, arnd@arndb.de, olof@lixom.net, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, guohanjun@huawei.com Subject: Re: [PATCH RFC 2/2] soc: Add a basic ACPI generic driver Message-ID: <20200128115629.GB2680602@kroah.com> References: <1580210059-199540-1-git-send-email-john.garry@huawei.com> <1580210059-199540-3-git-send-email-john.garry@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1580210059-199540-3-git-send-email-john.garry@huawei.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 28, 2020 at 07:14:19PM +0800, John Garry wrote: > Add a generic driver for platforms which populate their ACPI PPTT > processor package ID Type Structure according to suggestion in the ACPI > spec - see ACPI 6.2, section 5.2.29.3 ID structure Type 2. > > The soc_id is from member LEVEL_2_ID. > > For this, we need to use a whitelist of platforms which are known to > populate the structure as suggested. > > For now, only the vendor and soc_id fields are exposed. > > Signed-off-by: John Garry > --- > drivers/soc/Makefile | 1 + > drivers/soc/acpi_generic.c | 102 +++++++++++++++++++++++++++++++++++++ > 2 files changed, 103 insertions(+) > create mode 100644 drivers/soc/acpi_generic.c > > diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile > index 8b49d782a1ab..2a59a30a22cd 100644 > --- a/drivers/soc/Makefile > +++ b/drivers/soc/Makefile > @@ -3,6 +3,7 @@ > # Makefile for the Linux Kernel SOC specific device drivers. > # > > +obj-$(CONFIG_ACPI_PPTT) += acpi_generic.o > obj-$(CONFIG_ARCH_ACTIONS) += actions/ > obj-$(CONFIG_SOC_ASPEED) += aspeed/ > obj-$(CONFIG_ARCH_AT91) += atmel/ > diff --git a/drivers/soc/acpi_generic.c b/drivers/soc/acpi_generic.c > new file mode 100644 > index 000000000000..34a1f5f8e063 > --- /dev/null > +++ b/drivers/soc/acpi_generic.c > @@ -0,0 +1,102 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (c) John Garry, john.garry@huawei.com > + */ > + > +#define pr_fmt(fmt) "SOC ACPI GENERIC: " fmt You have a device, why do you need pr_fmt()? > + > +#include > +#include > + > +/* > + * Known platforms that fill in PPTT package ID structures according to > + * ACPI spec examples, that being: > + * - Custom driver attribute is in ID Type Structure VENDOR_ID member > + * - SoC id is in ID Type Structure LEVEL_2_ID member > + * See ACPI SPEC 6.2 Table 5-154 for PPTT ID Type Structure > + */ > +static struct acpi_platform_list plat_list[] = { > + {"HISI ", "HIP08 ", 0, ACPI_SIG_PPTT, all_versions}, > + { } /* End */ > +}; > + > +struct acpi_generic_soc_struct { > + struct soc_device_attribute dev_attr; > + u32 vendor; > +}; > + > +static ssize_t vendor_show(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + struct acpi_generic_soc_struct *soc = dev_get_drvdata(dev); > + u8 vendor_id[5] = {}; > + > + *(u32 *)vendor_id = soc->vendor; > + > + return sprintf(buf, "%s\n", vendor_id); > +} > + > +static DEVICE_ATTR_RO(vendor); > + > +static __init int soc_acpi_generic_init(void) > +{ > + int index; > + > + index = acpi_match_platform_list(plat_list); > + if (index < 0) > + return -ENOENT; > + > + index = 0; > + while (true) { > + struct acpi_pptt_package_info info; > + > + if (!acpi_pptt_get_package_info(index, &info)) { > + struct soc_device_attribute *soc_dev_attr; > + struct acpi_generic_soc_struct *soc; > + struct soc_device *soc_dev; > + u8 soc_id[9] = {}; > + > + *(u64 *)soc_id = info.LEVEL_2_ID; > + > + soc = kzalloc(sizeof(*soc), GFP_KERNEL); > + if (!soc) > + return -ENOMEM; > + > + soc_dev_attr = &soc->dev_attr; > + soc_dev_attr->soc_id = kasprintf(GFP_KERNEL, "%s", > + soc_id); > + if (!soc_dev_attr->soc_id) { > + kfree(soc); > + return -ENOMEM; > + } > + soc->vendor = info.vendor_id; > + > + soc_dev = soc_device_register(soc_dev_attr); > + if (IS_ERR(soc_dev)) { > + int ret = PTR_ERR(soc_dev); > + > + pr_info("could not register soc (%d) index=%d\n", > + ret, index); pr_err()? And shouldn't the core print out the error, not the person who calls it? > + kfree(soc_dev_attr->soc_id); > + kfree(soc); > + return ret; > + } > + dev_set_drvdata(soc_device_to_device(soc_dev), soc); > + device_create_file(soc_device_to_device(soc_dev), > + &dev_attr_vendor); You just raced with userspace and lost. Use the built-in api that I made _just_ because of SOC drivers to do this correctly. thanks, greg k-h