a3c89a1bcf545bd330ba04a0a1955a5d81837e09
[sfrench/cifs-2.6.git] / drivers / acpi / acpi_platform.c
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 const struct acpi_device_id forbidden_id_list[] = {
26         {"PNP0000", 0}, /* PIC */
27         {"PNP0100", 0}, /* Timer */
28         {"PNP0200", 0}, /* AT DMA Controller */
29         {"", 0},
30 };
31
32 /**
33  * acpi_create_platform_device - Create platform device for ACPI device node
34  * @adev: ACPI device node to create a platform device for.
35  *
36  * Check if the given @adev can be represented as a platform device and, if
37  * that's the case, create and register a platform device, populate its common
38  * resources and returns a pointer to it.  Otherwise, return %NULL.
39  *
40  * Name of the platform device will be the same as @adev's.
41  */
42 struct platform_device *acpi_create_platform_device(struct acpi_device *adev)
43 {
44         struct platform_device *pdev = NULL;
45         struct acpi_device *acpi_parent;
46         struct platform_device_info pdevinfo;
47         struct resource_list_entry *rentry;
48         struct list_head resource_list;
49         struct resource *resources = NULL;
50         int count;
51
52         /* If the ACPI node already has a physical device attached, skip it. */
53         if (adev->physical_node_count)
54                 return NULL;
55
56         if (!acpi_match_device_ids(adev, forbidden_id_list))
57                 return ERR_PTR(-EINVAL);
58
59         INIT_LIST_HEAD(&resource_list);
60         count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
61         if (count < 0) {
62                 return NULL;
63         } else if (count > 0) {
64                 resources = kmalloc(count * sizeof(struct resource),
65                                     GFP_KERNEL);
66                 if (!resources) {
67                         dev_err(&adev->dev, "No memory for resources\n");
68                         acpi_dev_free_resource_list(&resource_list);
69                         return ERR_PTR(-ENOMEM);
70                 }
71                 count = 0;
72                 list_for_each_entry(rentry, &resource_list, node)
73                         resources[count++] = rentry->res;
74
75                 acpi_dev_free_resource_list(&resource_list);
76         }
77
78         memset(&pdevinfo, 0, sizeof(pdevinfo));
79         /*
80          * If the ACPI node has a parent and that parent has a physical device
81          * attached to it, that physical device should be the parent of the
82          * platform device we are about to create.
83          */
84         pdevinfo.parent = NULL;
85         acpi_parent = adev->parent;
86         if (acpi_parent) {
87                 struct acpi_device_physical_node *entry;
88                 struct list_head *list;
89
90                 mutex_lock(&acpi_parent->physical_node_lock);
91                 list = &acpi_parent->physical_node_list;
92                 if (!list_empty(list)) {
93                         entry = list_first_entry(list,
94                                         struct acpi_device_physical_node,
95                                         node);
96                         pdevinfo.parent = entry->dev;
97                 }
98                 mutex_unlock(&acpi_parent->physical_node_lock);
99         }
100         pdevinfo.name = dev_name(&adev->dev);
101         pdevinfo.id = -1;
102         pdevinfo.res = resources;
103         pdevinfo.num_res = count;
104         pdevinfo.acpi_node.companion = adev;
105         pdev = platform_device_register_full(&pdevinfo);
106         if (IS_ERR(pdev))
107                 dev_err(&adev->dev, "platform device creation failed: %ld\n",
108                         PTR_ERR(pdev));
109         else
110                 dev_dbg(&adev->dev, "created platform device %s\n",
111                         dev_name(&pdev->dev));
112
113         kfree(resources);
114         return pdev;
115 }
116 EXPORT_SYMBOL_GPL(acpi_create_platform_device);