1 /* 2 * ACPI support for platform bus type. 3 * 4 * Copyright (C) 2012, Intel Corporation 5 * Authors: Mika Westerberg <mika.westerberg@linux.intel.com> 6 * Mathias Nyman <mathias.nyman@linux.intel.com> 7 * Rafael J. Wysocki <rafael.j.wysocki@intel.com> 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License version 2 as 11 * published by the Free Software Foundation. 12 */ 13 14 #include <linux/acpi.h> 15 #include <linux/device.h> 16 #include <linux/err.h> 17 #include <linux/kernel.h> 18 #include <linux/module.h> 19 #include <linux/platform_device.h> 20 21 #include "internal.h" 22 23 ACPI_MODULE_NAME("platform"); 24 25 /* 26 * The following ACPI IDs are known to be suitable for representing as 27 * platform devices. 28 */ 29 static const struct acpi_device_id acpi_platform_device_ids[] = { 30 31 { "PNP0D40" }, 32 { "ACPI0003" }, 33 { "VPC2004" }, 34 35 /* Intel Smart Sound Technology */ 36 { "INT33C8" }, 37 { "80860F28" }, 38 39 { } 40 }; 41 42 /** 43 * acpi_create_platform_device - Create platform device for ACPI device node 44 * @adev: ACPI device node to create a platform device for. 45 * @id: ACPI device ID used to match @adev. 46 * 47 * Check if the given @adev can be represented as a platform device and, if 48 * that's the case, create and register a platform device, populate its common 49 * resources and returns a pointer to it. Otherwise, return %NULL. 50 * 51 * Name of the platform device will be the same as @adev's. 52 */ 53 int acpi_create_platform_device(struct acpi_device *adev, 54 const struct acpi_device_id *id) 55 { 56 struct platform_device *pdev = NULL; 57 struct acpi_device *acpi_parent; 58 struct platform_device_info pdevinfo; 59 struct resource_list_entry *rentry; 60 struct list_head resource_list; 61 struct resource *resources = NULL; 62 int count; 63 64 /* If the ACPI node already has a physical device attached, skip it. */ 65 if (adev->physical_node_count) 66 return 0; 67 68 INIT_LIST_HEAD(&resource_list); 69 count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL); 70 if (count < 0) { 71 return 0; 72 } else if (count > 0) { 73 resources = kmalloc(count * sizeof(struct resource), 74 GFP_KERNEL); 75 if (!resources) { 76 dev_err(&adev->dev, "No memory for resources\n"); 77 acpi_dev_free_resource_list(&resource_list); 78 return -ENOMEM; 79 } 80 count = 0; 81 list_for_each_entry(rentry, &resource_list, node) 82 resources[count++] = rentry->res; 83 84 acpi_dev_free_resource_list(&resource_list); 85 } 86 87 memset(&pdevinfo, 0, sizeof(pdevinfo)); 88 /* 89 * If the ACPI node has a parent and that parent has a physical device 90 * attached to it, that physical device should be the parent of the 91 * platform device we are about to create. 92 */ 93 pdevinfo.parent = NULL; 94 acpi_parent = adev->parent; 95 if (acpi_parent) { 96 struct acpi_device_physical_node *entry; 97 struct list_head *list; 98 99 mutex_lock(&acpi_parent->physical_node_lock); 100 list = &acpi_parent->physical_node_list; 101 if (!list_empty(list)) { 102 entry = list_first_entry(list, 103 struct acpi_device_physical_node, 104 node); 105 pdevinfo.parent = entry->dev; 106 } 107 mutex_unlock(&acpi_parent->physical_node_lock); 108 } 109 pdevinfo.name = dev_name(&adev->dev); 110 pdevinfo.id = -1; 111 pdevinfo.res = resources; 112 pdevinfo.num_res = count; 113 pdevinfo.acpi_node.handle = adev->handle; 114 pdev = platform_device_register_full(&pdevinfo); 115 if (IS_ERR(pdev)) { 116 dev_err(&adev->dev, "platform device creation failed: %ld\n", 117 PTR_ERR(pdev)); 118 pdev = NULL; 119 } else { 120 dev_dbg(&adev->dev, "created platform device %s\n", 121 dev_name(&pdev->dev)); 122 } 123 124 kfree(resources); 125 return 1; 126 } 127 128 static struct acpi_scan_handler platform_handler = { 129 .ids = acpi_platform_device_ids, 130 .attach = acpi_create_platform_device, 131 }; 132 133 void __init acpi_platform_init(void) 134 { 135 acpi_scan_add_handler(&platform_handler); 136 } 137