xref: /openbmc/linux/drivers/acpi/acpi_platform.c (revision 62e59c4e)
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/pci.h>
21 #include <linux/platform_device.h>
22 
23 #include "internal.h"
24 
25 ACPI_MODULE_NAME("platform");
26 
27 static const struct acpi_device_id forbidden_id_list[] = {
28 	{"PNP0000",  0},	/* PIC */
29 	{"PNP0100",  0},	/* Timer */
30 	{"PNP0200",  0},	/* AT DMA Controller */
31 	{"ACPI0009", 0},	/* IOxAPIC */
32 	{"ACPI000A", 0},	/* IOAPIC */
33 	{"SMB0001",  0},	/* ACPI SMBUS virtual device */
34 	{"", 0},
35 };
36 
37 static void acpi_platform_fill_resource(struct acpi_device *adev,
38 	const struct resource *src, struct resource *dest)
39 {
40 	struct device *parent;
41 
42 	*dest = *src;
43 
44 	/*
45 	 * If the device has parent we need to take its resources into
46 	 * account as well because this device might consume part of those.
47 	 */
48 	parent = acpi_get_first_physical_node(adev->parent);
49 	if (parent && dev_is_pci(parent))
50 		dest->parent = pci_find_resource(to_pci_dev(parent), dest);
51 }
52 
53 /**
54  * acpi_create_platform_device - Create platform device for ACPI device node
55  * @adev: ACPI device node to create a platform device for.
56  * @properties: Optional collection of build-in properties.
57  *
58  * Check if the given @adev can be represented as a platform device and, if
59  * that's the case, create and register a platform device, populate its common
60  * resources and returns a pointer to it.  Otherwise, return %NULL.
61  *
62  * Name of the platform device will be the same as @adev's.
63  */
64 struct platform_device *acpi_create_platform_device(struct acpi_device *adev,
65 					struct property_entry *properties)
66 {
67 	struct platform_device *pdev = NULL;
68 	struct platform_device_info pdevinfo;
69 	struct resource_entry *rentry;
70 	struct list_head resource_list;
71 	struct resource *resources = NULL;
72 	int count;
73 
74 	/* If the ACPI node already has a physical device attached, skip it. */
75 	if (adev->physical_node_count)
76 		return NULL;
77 
78 	if (!acpi_match_device_ids(adev, forbidden_id_list))
79 		return ERR_PTR(-EINVAL);
80 
81 	INIT_LIST_HEAD(&resource_list);
82 	count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
83 	if (count < 0) {
84 		return NULL;
85 	} else if (count > 0) {
86 		resources = kcalloc(count, sizeof(struct resource),
87 				    GFP_KERNEL);
88 		if (!resources) {
89 			dev_err(&adev->dev, "No memory for resources\n");
90 			acpi_dev_free_resource_list(&resource_list);
91 			return ERR_PTR(-ENOMEM);
92 		}
93 		count = 0;
94 		list_for_each_entry(rentry, &resource_list, node)
95 			acpi_platform_fill_resource(adev, rentry->res,
96 						    &resources[count++]);
97 
98 		acpi_dev_free_resource_list(&resource_list);
99 	}
100 
101 	memset(&pdevinfo, 0, sizeof(pdevinfo));
102 	/*
103 	 * If the ACPI node has a parent and that parent has a physical device
104 	 * attached to it, that physical device should be the parent of the
105 	 * platform device we are about to create.
106 	 */
107 	pdevinfo.parent = adev->parent ?
108 		acpi_get_first_physical_node(adev->parent) : NULL;
109 	pdevinfo.name = dev_name(&adev->dev);
110 	pdevinfo.id = -1;
111 	pdevinfo.res = resources;
112 	pdevinfo.num_res = count;
113 	pdevinfo.fwnode = acpi_fwnode_handle(adev);
114 	pdevinfo.properties = properties;
115 
116 	if (acpi_dma_supported(adev))
117 		pdevinfo.dma_mask = DMA_BIT_MASK(32);
118 	else
119 		pdevinfo.dma_mask = 0;
120 
121 	pdev = platform_device_register_full(&pdevinfo);
122 	if (IS_ERR(pdev))
123 		dev_err(&adev->dev, "platform device creation failed: %ld\n",
124 			PTR_ERR(pdev));
125 	else {
126 		set_dev_node(&pdev->dev, acpi_get_node(adev->handle));
127 		dev_dbg(&adev->dev, "created platform device %s\n",
128 			dev_name(&pdev->dev));
129 	}
130 
131 	kfree(resources);
132 
133 	return pdev;
134 }
135 EXPORT_SYMBOL_GPL(acpi_create_platform_device);
136