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/dma-mapping.h> 20 #include <linux/platform_device.h> 21 22 #include "internal.h" 23 24 ACPI_MODULE_NAME("platform"); 25 26 static const struct acpi_device_id forbidden_id_list[] = { 27 {"PNP0000", 0}, /* PIC */ 28 {"PNP0100", 0}, /* Timer */ 29 {"PNP0200", 0}, /* AT DMA Controller */ 30 {"", 0}, 31 }; 32 33 /** 34 * acpi_create_platform_device - Create platform device for ACPI device node 35 * @adev: ACPI device node to create a platform device for. 36 * 37 * Check if the given @adev can be represented as a platform device and, if 38 * that's the case, create and register a platform device, populate its common 39 * resources and returns a pointer to it. Otherwise, return %NULL. 40 * 41 * Name of the platform device will be the same as @adev's. 42 */ 43 struct platform_device *acpi_create_platform_device(struct acpi_device *adev) 44 { 45 struct platform_device *pdev = NULL; 46 struct acpi_device *acpi_parent; 47 struct platform_device_info pdevinfo; 48 struct resource_entry *rentry; 49 struct list_head resource_list; 50 struct resource *resources = NULL; 51 int count; 52 53 /* If the ACPI node already has a physical device attached, skip it. */ 54 if (adev->physical_node_count) 55 return NULL; 56 57 if (!acpi_match_device_ids(adev, forbidden_id_list)) 58 return ERR_PTR(-EINVAL); 59 60 INIT_LIST_HEAD(&resource_list); 61 count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL); 62 if (count < 0) { 63 return NULL; 64 } else if (count > 0) { 65 resources = kmalloc(count * sizeof(struct resource), 66 GFP_KERNEL); 67 if (!resources) { 68 dev_err(&adev->dev, "No memory for resources\n"); 69 acpi_dev_free_resource_list(&resource_list); 70 return ERR_PTR(-ENOMEM); 71 } 72 count = 0; 73 list_for_each_entry(rentry, &resource_list, node) 74 resources[count++] = *rentry->res; 75 76 acpi_dev_free_resource_list(&resource_list); 77 } 78 79 memset(&pdevinfo, 0, sizeof(pdevinfo)); 80 /* 81 * If the ACPI node has a parent and that parent has a physical device 82 * attached to it, that physical device should be the parent of the 83 * platform device we are about to create. 84 */ 85 pdevinfo.parent = NULL; 86 acpi_parent = adev->parent; 87 if (acpi_parent) { 88 struct acpi_device_physical_node *entry; 89 struct list_head *list; 90 91 mutex_lock(&acpi_parent->physical_node_lock); 92 list = &acpi_parent->physical_node_list; 93 if (!list_empty(list)) { 94 entry = list_first_entry(list, 95 struct acpi_device_physical_node, 96 node); 97 pdevinfo.parent = entry->dev; 98 } 99 mutex_unlock(&acpi_parent->physical_node_lock); 100 } 101 pdevinfo.name = dev_name(&adev->dev); 102 pdevinfo.id = -1; 103 pdevinfo.res = resources; 104 pdevinfo.num_res = count; 105 pdevinfo.fwnode = acpi_fwnode_handle(adev); 106 107 if (acpi_dma_supported(adev)) 108 pdevinfo.dma_mask = DMA_BIT_MASK(32); 109 else 110 pdevinfo.dma_mask = 0; 111 112 pdev = platform_device_register_full(&pdevinfo); 113 if (IS_ERR(pdev)) 114 dev_err(&adev->dev, "platform device creation failed: %ld\n", 115 PTR_ERR(pdev)); 116 else 117 dev_dbg(&adev->dev, "created platform device %s\n", 118 dev_name(&pdev->dev)); 119 120 kfree(resources); 121 return pdev; 122 } 123 EXPORT_SYMBOL_GPL(acpi_create_platform_device); 124