1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * ACPI support for platform bus type. 4 * 5 * Copyright (C) 2012, Intel Corporation 6 * 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/device.h> 13 #include <linux/err.h> 14 #include <linux/kernel.h> 15 #include <linux/module.h> 16 #include <linux/dma-mapping.h> 17 #include <linux/pci.h> 18 #include <linux/platform_device.h> 19 20 #include "internal.h" 21 22 ACPI_MODULE_NAME("platform"); 23 24 static const struct acpi_device_id forbidden_id_list[] = { 25 {"PNP0000", 0}, /* PIC */ 26 {"PNP0100", 0}, /* Timer */ 27 {"PNP0200", 0}, /* AT DMA Controller */ 28 {"ACPI0009", 0}, /* IOxAPIC */ 29 {"ACPI000A", 0}, /* IOAPIC */ 30 {"SMB0001", 0}, /* ACPI SMBUS virtual device */ 31 {"", 0}, 32 }; 33 34 static struct platform_device *acpi_platform_device_find_by_companion(struct acpi_device *adev) 35 { 36 struct device *dev; 37 38 dev = bus_find_device_by_acpi_dev(&platform_bus_type, adev); 39 return dev ? to_platform_device(dev) : NULL; 40 } 41 42 static int acpi_platform_device_remove_notify(struct notifier_block *nb, 43 unsigned long value, void *arg) 44 { 45 struct acpi_device *adev = arg; 46 struct platform_device *pdev; 47 48 switch (value) { 49 case ACPI_RECONFIG_DEVICE_ADD: 50 /* Nothing to do here */ 51 break; 52 case ACPI_RECONFIG_DEVICE_REMOVE: 53 if (!acpi_device_enumerated(adev)) 54 break; 55 56 pdev = acpi_platform_device_find_by_companion(adev); 57 if (!pdev) 58 break; 59 60 platform_device_unregister(pdev); 61 put_device(&pdev->dev); 62 break; 63 } 64 65 return NOTIFY_OK; 66 } 67 68 static struct notifier_block acpi_platform_notifier = { 69 .notifier_call = acpi_platform_device_remove_notify, 70 }; 71 72 static void acpi_platform_fill_resource(struct acpi_device *adev, 73 const struct resource *src, struct resource *dest) 74 { 75 struct device *parent; 76 77 *dest = *src; 78 79 /* 80 * If the device has parent we need to take its resources into 81 * account as well because this device might consume part of those. 82 */ 83 parent = acpi_get_first_physical_node(adev->parent); 84 if (parent && dev_is_pci(parent)) 85 dest->parent = pci_find_resource(to_pci_dev(parent), dest); 86 } 87 88 /** 89 * acpi_create_platform_device - Create platform device for ACPI device node 90 * @adev: ACPI device node to create a platform device for. 91 * @properties: Optional collection of build-in properties. 92 * 93 * Check if the given @adev can be represented as a platform device and, if 94 * that's the case, create and register a platform device, populate its common 95 * resources and returns a pointer to it. Otherwise, return %NULL. 96 * 97 * Name of the platform device will be the same as @adev's. 98 */ 99 struct platform_device *acpi_create_platform_device(struct acpi_device *adev, 100 struct property_entry *properties) 101 { 102 struct platform_device *pdev = NULL; 103 struct platform_device_info pdevinfo; 104 struct resource_entry *rentry; 105 struct list_head resource_list; 106 struct resource *resources = NULL; 107 int count; 108 109 /* If the ACPI node already has a physical device attached, skip it. */ 110 if (adev->physical_node_count) 111 return NULL; 112 113 if (!acpi_match_device_ids(adev, forbidden_id_list)) 114 return ERR_PTR(-EINVAL); 115 116 INIT_LIST_HEAD(&resource_list); 117 count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL); 118 if (count < 0) { 119 return NULL; 120 } else if (count > 0) { 121 resources = kcalloc(count, sizeof(struct resource), 122 GFP_KERNEL); 123 if (!resources) { 124 dev_err(&adev->dev, "No memory for resources\n"); 125 acpi_dev_free_resource_list(&resource_list); 126 return ERR_PTR(-ENOMEM); 127 } 128 count = 0; 129 list_for_each_entry(rentry, &resource_list, node) 130 acpi_platform_fill_resource(adev, rentry->res, 131 &resources[count++]); 132 133 acpi_dev_free_resource_list(&resource_list); 134 } 135 136 memset(&pdevinfo, 0, sizeof(pdevinfo)); 137 /* 138 * If the ACPI node has a parent and that parent has a physical device 139 * attached to it, that physical device should be the parent of the 140 * platform device we are about to create. 141 */ 142 pdevinfo.parent = adev->parent ? 143 acpi_get_first_physical_node(adev->parent) : NULL; 144 pdevinfo.name = dev_name(&adev->dev); 145 pdevinfo.id = -1; 146 pdevinfo.res = resources; 147 pdevinfo.num_res = count; 148 pdevinfo.fwnode = acpi_fwnode_handle(adev); 149 pdevinfo.properties = properties; 150 151 if (acpi_dma_supported(adev)) 152 pdevinfo.dma_mask = DMA_BIT_MASK(32); 153 else 154 pdevinfo.dma_mask = 0; 155 156 pdev = platform_device_register_full(&pdevinfo); 157 if (IS_ERR(pdev)) 158 dev_err(&adev->dev, "platform device creation failed: %ld\n", 159 PTR_ERR(pdev)); 160 else { 161 set_dev_node(&pdev->dev, acpi_get_node(adev->handle)); 162 dev_dbg(&adev->dev, "created platform device %s\n", 163 dev_name(&pdev->dev)); 164 } 165 166 kfree(resources); 167 168 return pdev; 169 } 170 EXPORT_SYMBOL_GPL(acpi_create_platform_device); 171 172 void __init acpi_platform_init(void) 173 { 174 acpi_reconfig_notifier_register(&acpi_platform_notifier); 175 } 176