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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DA41EC433FE for ; Wed, 22 Dec 2021 16:55:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344068AbhLVQzo (ORCPT ); Wed, 22 Dec 2021 11:55:44 -0500 Received: from mail-qv1-f49.google.com ([209.85.219.49]:33511 "EHLO mail-qv1-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344065AbhLVQzn (ORCPT ); Wed, 22 Dec 2021 11:55:43 -0500 Received: by mail-qv1-f49.google.com with SMTP id kk22so2910039qvb.0; Wed, 22 Dec 2021 08:55:43 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=TIb3KCoZoalgYMtgmFngJ24Q0HvmYtjyPu5slr0rQdQ=; b=DLXkkMEszE1oHbruA0G7zDYTRjfuuidZ95XvuWhb0ILGj9Dv3vagFhggMr2cTZxagS lqgprkLYEJuJDzPWQ4EDgPfCWkSzyikwjIV5UxtR4QoJWnqyXZjUTn4Y4XdZ0wKENVBI mia6FUpW9gjLF1t/QgYSGoI1Dhv+/5Ui+8qREF4GR5DOdDaEzEKuGSI4a5Wnttww4sqv KXaGJjzLub8TRi52l79dOw+kWZ1zMYTTRwafBxQEeuy7j2Qva45waEbk/S0/p2WmJKja VIAL5FeBDB7SZJ13mGz9vrbTVGc2HXv7aFSQqKt4fcSU5ZTaIdjR6VlhPbMaPfdbNzN4 jaaQ== X-Gm-Message-State: AOAM532fQpSKWhjkln7tEhHxsMleLa4OlmdXn9GATSra+GF+RgK/P920 iSmTfRfdU8Gury522ZQLgJKNH+mmYtYGT8jGhcI= X-Google-Smtp-Source: ABdhPJymkX1fhwwH/6Txl9mzAlT7e0it1er0umoDlgwA2LuTswxYFbPjBNHrPwaxC0z+TuDOwadxxbZp2j33dAamR8Q= X-Received: by 2002:a05:6214:2345:: with SMTP id hu5mr3191985qvb.130.1640192142943; Wed, 22 Dec 2021 08:55:42 -0800 (PST) MIME-Version: 1.0 References: <20211222143258.82305-1-heikki.krogerus@linux.intel.com> <20211222143258.82305-3-heikki.krogerus@linux.intel.com> In-Reply-To: <20211222143258.82305-3-heikki.krogerus@linux.intel.com> From: "Rafael J. Wysocki" Date: Wed, 22 Dec 2021 17:55:32 +0100 Message-ID: Subject: Re: [PATCH v4 2/5] acpi: Store CRC-32 hash of the _PLD in struct acpi_device To: Heikki Krogerus Cc: "Rafael J. Wysocki" , Greg Kroah-Hartman , Andy Shevchenko , Sakari Ailus , Prashant Malani , ACPI Devel Maling List , "open list:ULTRA-WIDEBAND (UWB) SUBSYSTEM:" , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On Wed, Dec 22, 2021 at 3:33 PM Heikki Krogerus wrote: > > Storing CRC-32 hash of the Physical Location of Device > object (_PLD) with devices that have it. The hash is stored > to a new struct acpi_device member "pld_crc". > > The hash makes it easier to find devices that share a > location, as there is no need to evaluate the entire object > every time. Knowledge about devices that share a location > can be used in device drivers that need to know the > connections to other components inside a system. USB3 ports > will for example always share their location with a USB2 > port. > > Signed-off-by: Heikki Krogerus > --- > drivers/acpi/scan.c | 16 ++++++++++++++++ > include/acpi/acpi_bus.h | 14 +++++++++++++- > 2 files changed, 29 insertions(+), 1 deletion(-) > > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > index 7ff55a197a583..113414c46b713 100644 > --- a/drivers/acpi/scan.c > +++ b/drivers/acpi/scan.c > @@ -19,6 +19,7 @@ > #include > #include > #include > +#include > > #include "internal.h" > > @@ -667,6 +668,19 @@ static int acpi_tie_acpi_dev(struct acpi_device *adev) > return 0; > } > > +static void acpi_store_pld_crc(struct acpi_device *adev) > +{ > + struct acpi_pld_info *pld; > + acpi_status status; > + > + status = acpi_get_physical_device_location(adev->handle, &pld); > + if (ACPI_FAILURE(status)) > + return; > + > + adev->pld_crc = crc32(~0, pld, sizeof(*pld)); > + ACPI_FREE(pld); > +} > + > static int __acpi_device_add(struct acpi_device *device, > void (*release)(struct device *)) > { > @@ -725,6 +739,8 @@ static int __acpi_device_add(struct acpi_device *device, > if (device->wakeup.flags.valid) > list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list); > > + acpi_store_pld_crc(device); > + > mutex_unlock(&acpi_device_lock); > > if (device->parent) > diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h > index 8e87ead2af341..1977db19458ed 100644 > --- a/include/acpi/acpi_bus.h > +++ b/include/acpi/acpi_bus.h > @@ -356,10 +356,23 @@ struct acpi_device_data { > struct list_head subnodes; > }; > > +/* > + * struct acpi_device_location - Device location based on _PLD > + * @devices: List of devices that share this location > + * @node: Entry in the internal list of locations > + * @pld_crc: CRC-32 hash of the _PLD > + */ > +struct acpi_device_location { > + struct list_head devices; > + struct list_head node; > + u32 pld_crc; > +}; Does this get used anywhere or is it a leftover from the previous version? > + > struct acpi_gpio_mapping; > > /* Device */ > struct acpi_device { > + u32 pld_crc; > int device_type; > acpi_handle handle; /* no handle for fixed hardware */ > struct fwnode_handle fwnode; > @@ -739,7 +752,6 @@ static inline void acpi_bus_put_acpi_device(struct acpi_device *adev) > > static inline int register_acpi_bus_type(void *bus) { return 0; } > static inline int unregister_acpi_bus_type(void *bus) { return 0; } > - > #endif /* CONFIG_ACPI */ > > #endif /*__ACPI_BUS_H__*/ > -- > 2.34.1 >