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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * ACPI support for platform bus type.4 *5 * Copyright (C) 2012, Intel Corporation6 * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>7 * Mathias Nyman <mathias.nyman@linux.intel.com>8 * Rafael J. Wysocki <rafael.j.wysocki@intel.com>9 */10 11#include <linux/acpi.h>12#include <linux/bits.h>13#include <linux/device.h>14#include <linux/err.h>15#include <linux/kernel.h>16#include <linux/module.h>17#include <linux/dma-mapping.h>18#include <linux/pci.h>19#include <linux/platform_device.h>20 21#include "internal.h"22 23/* Exclude devices that have no _CRS resources provided */24#define ACPI_ALLOW_WO_RESOURCES BIT(0)25 26static const struct acpi_device_id forbidden_id_list[] = {27 {"ACPI0009", 0}, /* IOxAPIC */28 {"ACPI000A", 0}, /* IOAPIC */29 {"PNP0000", 0}, /* PIC */30 {"PNP0100", 0}, /* Timer */31 {"PNP0200", 0}, /* AT DMA Controller */32 {ACPI_SMBUS_MS_HID, ACPI_ALLOW_WO_RESOURCES}, /* ACPI SMBUS virtual device */33 { }34};35 36static struct platform_device *acpi_platform_device_find_by_companion(struct acpi_device *adev)37{38 struct device *dev;39 40 dev = bus_find_device_by_acpi_dev(&platform_bus_type, adev);41 return dev ? to_platform_device(dev) : NULL;42}43 44static int acpi_platform_device_remove_notify(struct notifier_block *nb,45 unsigned long value, void *arg)46{47 struct acpi_device *adev = arg;48 struct platform_device *pdev;49 50 switch (value) {51 case ACPI_RECONFIG_DEVICE_ADD:52 /* Nothing to do here */53 break;54 case ACPI_RECONFIG_DEVICE_REMOVE:55 if (!acpi_device_enumerated(adev))56 break;57 58 pdev = acpi_platform_device_find_by_companion(adev);59 if (!pdev)60 break;61 62 platform_device_unregister(pdev);63 put_device(&pdev->dev);64 break;65 }66 67 return NOTIFY_OK;68}69 70static struct notifier_block acpi_platform_notifier = {71 .notifier_call = acpi_platform_device_remove_notify,72};73 74static void acpi_platform_fill_resource(struct acpi_device *adev,75 const struct resource *src, struct resource *dest)76{77 struct device *parent;78 79 *dest = *src;80 81 /*82 * If the device has parent we need to take its resources into83 * account as well because this device might consume part of those.84 */85 parent = acpi_get_first_physical_node(acpi_dev_parent(adev));86 if (parent && dev_is_pci(parent))87 dest->parent = pci_find_resource(to_pci_dev(parent), dest);88}89 90static unsigned int acpi_platform_resource_count(struct acpi_resource *ares, void *data)91{92 bool *has_resources = data;93 94 *has_resources = true;95 96 return AE_CTRL_TERMINATE;97}98 99/**100 * acpi_create_platform_device - Create platform device for ACPI device node101 * @adev: ACPI device node to create a platform device for.102 * @properties: Optional collection of build-in properties.103 *104 * Check if the given @adev can be represented as a platform device and, if105 * that's the case, create and register a platform device, populate its common106 * resources and returns a pointer to it. Otherwise, return %NULL.107 *108 * Name of the platform device will be the same as @adev's.109 */110struct platform_device *acpi_create_platform_device(struct acpi_device *adev,111 const struct property_entry *properties)112{113 struct acpi_device *parent = acpi_dev_parent(adev);114 struct platform_device *pdev = NULL;115 struct platform_device_info pdevinfo;116 const struct acpi_device_id *match;117 struct resource_entry *rentry;118 struct list_head resource_list;119 struct resource *resources = NULL;120 int count;121 122 /* If the ACPI node already has a physical device attached, skip it. */123 if (adev->physical_node_count)124 return NULL;125 126 match = acpi_match_acpi_device(forbidden_id_list, adev);127 if (match) {128 if (match->driver_data & ACPI_ALLOW_WO_RESOURCES) {129 bool has_resources = false;130 131 acpi_walk_resources(adev->handle, METHOD_NAME__CRS,132 acpi_platform_resource_count, &has_resources);133 if (has_resources)134 return ERR_PTR(-EINVAL);135 } else {136 return ERR_PTR(-EINVAL);137 }138 }139 140 INIT_LIST_HEAD(&resource_list);141 count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);142 if (count < 0)143 return NULL;144 if (count > 0) {145 resources = kcalloc(count, sizeof(*resources), GFP_KERNEL);146 if (!resources) {147 acpi_dev_free_resource_list(&resource_list);148 return ERR_PTR(-ENOMEM);149 }150 count = 0;151 list_for_each_entry(rentry, &resource_list, node)152 acpi_platform_fill_resource(adev, rentry->res,153 &resources[count++]);154 155 acpi_dev_free_resource_list(&resource_list);156 }157 158 memset(&pdevinfo, 0, sizeof(pdevinfo));159 /*160 * If the ACPI node has a parent and that parent has a physical device161 * attached to it, that physical device should be the parent of the162 * platform device we are about to create.163 */164 pdevinfo.parent = parent ? acpi_get_first_physical_node(parent) : NULL;165 pdevinfo.name = dev_name(&adev->dev);166 pdevinfo.id = PLATFORM_DEVID_NONE;167 pdevinfo.res = resources;168 pdevinfo.num_res = count;169 pdevinfo.fwnode = acpi_fwnode_handle(adev);170 pdevinfo.properties = properties;171 172 if (acpi_dma_supported(adev))173 pdevinfo.dma_mask = DMA_BIT_MASK(32);174 else175 pdevinfo.dma_mask = 0;176 177 pdev = platform_device_register_full(&pdevinfo);178 if (IS_ERR(pdev))179 dev_err(&adev->dev, "platform device creation failed: %ld\n",180 PTR_ERR(pdev));181 else {182 set_dev_node(&pdev->dev, acpi_get_node(adev->handle));183 dev_dbg(&adev->dev, "created platform device %s\n",184 dev_name(&pdev->dev));185 }186 187 kfree(resources);188 189 return pdev;190}191EXPORT_SYMBOL_GPL(acpi_create_platform_device);192 193void __init acpi_platform_init(void)194{195 acpi_reconfig_notifier_register(&acpi_platform_notifier);196}197