xref: /linux/drivers/acpi/acpi_platform.c (revision 1571875beecd5de9657f73931449bda1b1329b6f)
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  * @properties: Optional collection of build-in properties.
37  *
38  * Check if the given @adev can be represented as a platform device and, if
39  * that's the case, create and register a platform device, populate its common
40  * resources and returns a pointer to it.  Otherwise, return %NULL.
41  *
42  * Name of the platform device will be the same as @adev's.
43  */
44 struct platform_device *acpi_create_platform_device(struct acpi_device *adev,
45 					struct property_entry *properties)
46 {
47 	struct platform_device *pdev = NULL;
48 	struct platform_device_info pdevinfo;
49 	struct resource_entry *rentry;
50 	struct list_head resource_list;
51 	struct resource *resources = NULL;
52 	int count;
53 
54 	/* If the ACPI node already has a physical device attached, skip it. */
55 	if (adev->physical_node_count)
56 		return NULL;
57 
58 	if (!acpi_match_device_ids(adev, forbidden_id_list))
59 		return ERR_PTR(-EINVAL);
60 
61 	INIT_LIST_HEAD(&resource_list);
62 	count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
63 	if (count < 0) {
64 		return NULL;
65 	} else if (count > 0) {
66 		resources = kzalloc(count * sizeof(struct resource),
67 				    GFP_KERNEL);
68 		if (!resources) {
69 			dev_err(&adev->dev, "No memory for resources\n");
70 			acpi_dev_free_resource_list(&resource_list);
71 			return ERR_PTR(-ENOMEM);
72 		}
73 		count = 0;
74 		list_for_each_entry(rentry, &resource_list, node)
75 			resources[count++] = *rentry->res;
76 
77 		acpi_dev_free_resource_list(&resource_list);
78 	}
79 
80 	memset(&pdevinfo, 0, sizeof(pdevinfo));
81 	/*
82 	 * If the ACPI node has a parent and that parent has a physical device
83 	 * attached to it, that physical device should be the parent of the
84 	 * platform device we are about to create.
85 	 */
86 	pdevinfo.parent = adev->parent ?
87 		acpi_get_first_physical_node(adev->parent) : NULL;
88 	pdevinfo.name = dev_name(&adev->dev);
89 	pdevinfo.id = -1;
90 	pdevinfo.res = resources;
91 	pdevinfo.num_res = count;
92 	pdevinfo.fwnode = acpi_fwnode_handle(adev);
93 	pdevinfo.properties = properties;
94 
95 	if (acpi_dma_supported(adev))
96 		pdevinfo.dma_mask = DMA_BIT_MASK(32);
97 	else
98 		pdevinfo.dma_mask = 0;
99 
100 	pdev = platform_device_register_full(&pdevinfo);
101 	if (IS_ERR(pdev))
102 		dev_err(&adev->dev, "platform device creation failed: %ld\n",
103 			PTR_ERR(pdev));
104 	else
105 		dev_dbg(&adev->dev, "created platform device %s\n",
106 			dev_name(&pdev->dev));
107 
108 	kfree(resources);
109 	return pdev;
110 }
111 EXPORT_SYMBOL_GPL(acpi_create_platform_device);
112