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 static int acpi_create_platform_clks(struct acpi_device *adev) 26 { 27 static struct platform_device *pdev; 28 29 /* Create Lynxpoint LPSS clocks */ 30 if (!pdev && !strncmp(acpi_device_hid(adev), "INT33C", 6)) { 31 pdev = platform_device_register_simple("clk-lpt", -1, NULL, 0); 32 if (IS_ERR(pdev)) 33 return PTR_ERR(pdev); 34 } 35 36 return 0; 37 } 38 39 /** 40 * acpi_create_platform_device - Create platform device for ACPI device node 41 * @adev: ACPI device node to create a platform device for. 42 * @flags: ACPI_PLATFORM_* flags that affect the creation of the platform 43 * devices. 44 * 45 * Check if the given @adev can be represented as a platform device and, if 46 * that's the case, create and register a platform device, populate its common 47 * resources and returns a pointer to it. Otherwise, return %NULL. 48 * 49 * Name of the platform device will be the same as @adev's. 50 */ 51 struct platform_device *acpi_create_platform_device(struct acpi_device *adev, 52 unsigned long flags) 53 { 54 struct platform_device *pdev = NULL; 55 struct acpi_device *acpi_parent; 56 struct platform_device_info pdevinfo; 57 struct resource_list_entry *rentry; 58 struct list_head resource_list; 59 struct resource *resources; 60 int count; 61 62 if ((flags & ACPI_PLATFORM_CLK) && acpi_create_platform_clks(adev)) { 63 dev_err(&adev->dev, "failed to create clocks\n"); 64 return NULL; 65 } 66 67 /* If the ACPI node already has a physical device attached, skip it. */ 68 if (adev->physical_node_count) 69 return NULL; 70 71 INIT_LIST_HEAD(&resource_list); 72 count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL); 73 if (count <= 0) 74 return NULL; 75 76 resources = kmalloc(count * sizeof(struct resource), GFP_KERNEL); 77 if (!resources) { 78 dev_err(&adev->dev, "No memory for resources\n"); 79 acpi_dev_free_resource_list(&resource_list); 80 return NULL; 81 } 82 count = 0; 83 list_for_each_entry(rentry, &resource_list, node) 84 resources[count++] = rentry->res; 85 86 acpi_dev_free_resource_list(&resource_list); 87 88 memset(&pdevinfo, 0, sizeof(pdevinfo)); 89 /* 90 * If the ACPI node has a parent and that parent has a physical device 91 * attached to it, that physical device should be the parent of the 92 * platform device we are about to create. 93 */ 94 pdevinfo.parent = NULL; 95 acpi_parent = adev->parent; 96 if (acpi_parent) { 97 struct acpi_device_physical_node *entry; 98 struct list_head *list; 99 100 mutex_lock(&acpi_parent->physical_node_lock); 101 list = &acpi_parent->physical_node_list; 102 if (!list_empty(list)) { 103 entry = list_first_entry(list, 104 struct acpi_device_physical_node, 105 node); 106 pdevinfo.parent = entry->dev; 107 } 108 mutex_unlock(&acpi_parent->physical_node_lock); 109 } 110 pdevinfo.name = dev_name(&adev->dev); 111 pdevinfo.id = -1; 112 pdevinfo.res = resources; 113 pdevinfo.num_res = count; 114 pdevinfo.acpi_node.handle = adev->handle; 115 pdev = platform_device_register_full(&pdevinfo); 116 if (IS_ERR(pdev)) { 117 dev_err(&adev->dev, "platform device creation failed: %ld\n", 118 PTR_ERR(pdev)); 119 pdev = NULL; 120 } else { 121 dev_dbg(&adev->dev, "created platform device %s\n", 122 dev_name(&pdev->dev)); 123 } 124 125 kfree(resources); 126 return pdev; 127 } 128