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
24ACPI_MODULE_NAME("platform");
25
26static 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 */
43struct 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_list_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.acpi_node.companion = adev;
106	pdevinfo.dma_mask = DMA_BIT_MASK(32);
107	pdev = platform_device_register_full(&pdevinfo);
108	if (IS_ERR(pdev))
109		dev_err(&adev->dev, "platform device creation failed: %ld\n",
110			PTR_ERR(pdev));
111	else
112		dev_dbg(&adev->dev, "created platform device %s\n",
113			dev_name(&pdev->dev));
114
115	kfree(resources);
116	return pdev;
117}
118EXPORT_SYMBOL_GPL(acpi_create_platform_device);
119