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=-10.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 D2C93C433E2 for ; Fri, 28 Aug 2020 07:43:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9D34920C56 for ; Fri, 28 Aug 2020 07:43:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598600629; bh=WexA/mvpkGUeqg62kxLVzIKks8M2SdxjyP7pEBESRxQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=yFKDvGWj6yEnQ1TzGAOtEfSwxm8cD11Y6lVJJN00tu/Jmgw6jlZoFC3vWp/ox+/n0 vJ97onjy1rZ5rUT7jQi5AehMiyq/B2ucTQezBTU5/6/jKuS9/GLDqeHFJjSRJTs3nU tKhYXAnQuM3AHDBa0dv7WRa3peIClJkvJ1Zx86yQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728515AbgH1Hns (ORCPT ); Fri, 28 Aug 2020 03:43:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:40224 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726566AbgH1Hnr (ORCPT ); Fri, 28 Aug 2020 03:43:47 -0400 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 EC24120776; Fri, 28 Aug 2020 07:43:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598600626; bh=WexA/mvpkGUeqg62kxLVzIKks8M2SdxjyP7pEBESRxQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=TYp4tXV89t7nHhHpv3B7rjSsgs/0xCFtEd+NcafOBU8wKFX9sfe2yzyfvtnRs/1cH 9EZSDfTVBO0ntxePdJ9qShHyW4HpL2g98DnlFtcANTyMNGRlFLeH5CToyNWqm+5LST Ey6cpRV89k7toL1NyiLEb7qaWV6Y+f/CLMfjKF1U= Date: Fri, 28 Aug 2020 09:43:59 +0200 From: Greg Kroah-Hartman To: Rajmohan Mani Cc: Darren Hart , Andy Shevchenko , Mika Westerberg , Dmitry Torokhov , Lee Jones , Ayman Bagabas , Masahiro Yamada , Jithu Joseph , =?utf-8?B?Qmxhxb4=?= Hrastnik , Srinivas Pandruvada , linux-kernel@vger.kernel.org, platform-driver-x86@vger.kernel.org, Heikki Krogerus , linux-usb@vger.kernel.org, pmalani@chromium.org, bleung@chromium.org Subject: Re: [PATCH v2 1/3] platform/x86: Add Intel Input Output Manager (IOM) driver Message-ID: <20200828074359.GC942935@kroah.com> References: <20200822040508.23510-1-rajmohan.mani@intel.com> <20200822040508.23510-2-rajmohan.mani@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200822040508.23510-2-rajmohan.mani@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 21, 2020 at 09:05:06PM -0700, Rajmohan Mani wrote: > Input Output Manager (IOM) is part of the Tiger Lake SoC that > configures the Type-C Sub System (TCSS). IOM is a micro controller > that handles Type-C topology, configuration and PM functions of > various Type-C devices connected on the platform. > > This driver helps read relevant information such as Type-C port > status (whether a device is connected to a Type-C port or not) and > the activity type on the Type-C ports (such as USB, Display Port, > Thunderbolt), for consumption by other drivers. > > Currently intel_iom_port_status() API is exported by this driver, > that has information about the Type-C port status and port activity > type. > > Signed-off-by: Rajmohan Mani > --- > drivers/platform/x86/Kconfig | 16 ++++ > drivers/platform/x86/Makefile | 1 + > drivers/platform/x86/intel_iom.c | 95 +++++++++++++++++++++ > include/linux/platform_data/x86/intel_iom.h | 49 +++++++++++ > 4 files changed, 161 insertions(+) > create mode 100644 drivers/platform/x86/intel_iom.c > create mode 100644 include/linux/platform_data/x86/intel_iom.h > > diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig > index 40219bba6801..f09b4b525ea5 100644 > --- a/drivers/platform/x86/Kconfig > +++ b/drivers/platform/x86/Kconfig > @@ -837,6 +837,22 @@ config INTEL_INT0002_VGPIO > To compile this driver as a module, choose M here: the module will > be called intel_int0002_vgpio. > > +config INTEL_IOM > + tristate "Intel Input Output Manager (IOM) driver" > + depends on ACPI && PCI > + help > + This driver helps read relevant information such as Type-C port > + status (whether a device is connected to a Type-C port or not) > + and the activity type on the Type-C ports (such as USB, Display > + Port, Thunderbolt), for consumption by other drivers. > + > + Currently intel_iom_port_status() API is exported by this driver, > + that has information about the Type-C port status and port activity > + type. > + > + To compile this driver as a module, choose M here: the module will > + be called intel_iom. > + > config INTEL_MENLOW > tristate "Thermal Management driver for Intel menlow platform" > depends on ACPI_THERMAL > diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile > index 5f823f7eff45..b44f706074c3 100644 > --- a/drivers/platform/x86/Makefile > +++ b/drivers/platform/x86/Makefile > @@ -77,6 +77,7 @@ intel_cht_int33fe-objs := intel_cht_int33fe_common.o \ > intel_cht_int33fe_microb.o > obj-$(CONFIG_INTEL_HID_EVENT) += intel-hid.o > obj-$(CONFIG_INTEL_INT0002_VGPIO) += intel_int0002_vgpio.o > +obj-$(CONFIG_INTEL_IOM) += intel_iom.o > obj-$(CONFIG_INTEL_MENLOW) += intel_menlow.o > obj-$(CONFIG_INTEL_OAKTRAIL) += intel_oaktrail.o > obj-$(CONFIG_INTEL_VBTN) += intel-vbtn.o > diff --git a/drivers/platform/x86/intel_iom.c b/drivers/platform/x86/intel_iom.c > new file mode 100644 > index 000000000000..cda7716410c6 > --- /dev/null > +++ b/drivers/platform/x86/intel_iom.c > @@ -0,0 +1,95 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Intel Core SoC Input Output Manager (IOM) driver. > + * > + * This driver provides access to the Input Output Manager (IOM) (that > + * is part of Tiger Lake SoC) registers that can be used to know about > + * Type-C Sub System related information (such as Type-C port status, > + * activity type on Type-C ports). > + * > + * Copyright (C) 2020, Intel Corporation > + * Author: Rajmohan Mani > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +#define IOM_PORT_STATUS_OFFSET 0x560 > + > +struct intel_iom { > + struct device *dev; > + void __iomem *regbar; > +}; > + > +static struct intel_iom *iom; > + > +/** > + * intel_iom_port_status() - Get status bits for the Type-C port > + * @port: Type-C port number > + * @status: pointer to receive the status bits > + * > + * Returns 0 on success, error otherwise. > + */ > +int intel_iom_port_status(u8 port, u32 *status) > +{ > + void __iomem *reg; > + > + if (!iom || !iom->dev || !iom->regbar) > + return -ENODEV; > + > + if (!status || (port > IOM_MAX_PORTS - 1)) > + return -EINVAL; > + > + reg = iom->regbar + IOM_PORT_STATUS_OFFSET + IOM_REG_LEN * port; > + > + *status = ioread32(reg); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(intel_iom_port_status); > + > +static int intel_iom_probe(struct platform_device *pdev) > +{ > + void __iomem *addr; > + > + /* only one IOM device is supported */ > + if (iom) > + return -EBUSY; > + > + iom = devm_kzalloc(&pdev->dev, sizeof(*iom), GFP_KERNEL); > + if (!iom) > + return -ENOMEM; > + > + addr = devm_platform_ioremap_resource(pdev, 0); > + if (IS_ERR(addr)) > + return PTR_ERR(addr); > + > + iom->regbar = addr; > + iom->dev = &pdev->dev; > + > + return 0; > +} > + > +static const struct acpi_device_id intel_iom_acpi_ids[] = { > + { "INTC1072" }, > + {} > +}; > +MODULE_DEVICE_TABLE(acpi, intel_iom_acpi_ids); > + > +static struct platform_driver intel_iom_driver = { > + .probe = intel_iom_probe, > + .driver = { > + .name = "intel_iom", > + .acpi_match_table = intel_iom_acpi_ids, > + }, > +}; > + > +module_platform_driver_probe(intel_iom_driver, intel_iom_probe); > + > +MODULE_AUTHOR("Rajmohan Mani "); > +MODULE_DESCRIPTION("Intel IOM driver"); > +MODULE_LICENSE("GPL v2"); I still find this crazy that a whole separate driver is created just to read a single 32bit value. Why not put this logic in the driver that wants to read that value? That would be much simpler, smaller, and more obvious. thanks, greg k-h