xref: /openbmc/linux/drivers/acpi/acpi_platform.c (revision fcc8487d)
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 	{"", 0},
34 };
35 
36 static void acpi_platform_fill_resource(struct acpi_device *adev,
37 	const struct resource *src, struct resource *dest)
38 {
39 	struct device *parent;
40 
41 	*dest = *src;
42 
43 	/*
44 	 * If the device has parent we need to take its resources into
45 	 * account as well because this device might consume part of those.
46 	 */
47 	parent = acpi_get_first_physical_node(adev->parent);
48 	if (parent && dev_is_pci(parent))
49 		dest->parent = pci_find_resource(to_pci_dev(parent), dest);
50 }
51 
52 /**
53  * acpi_create_platform_device - Create platform device for ACPI device node
54  * @adev: ACPI device node to create a platform device for.
55  * @properties: Optional collection of build-in properties.
56  *
57  * Check if the given @adev can be represented as a platform device and, if
58  * that's the case, create and register a platform device, populate its common
59  * resources and returns a pointer to it.  Otherwise, return %NULL.
60  *
61  * Name of the platform device will be the same as @adev's.
62  */
63 struct platform_device *acpi_create_platform_device(struct acpi_device *adev,
64 					struct property_entry *properties)
65 {
66 	struct platform_device *pdev = NULL;
67 	struct platform_device_info pdevinfo;
68 	struct resource_entry *rentry;
69 	struct list_head resource_list;
70 	struct resource *resources = NULL;
71 	int count;
72 
73 	/* If the ACPI node already has a physical device attached, skip it. */
74 	if (adev->physical_node_count)
75 		return NULL;
76 
77 	if (!acpi_match_device_ids(adev, forbidden_id_list))
78 		return ERR_PTR(-EINVAL);
79 
80 	INIT_LIST_HEAD(&resource_list);
81 	count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
82 	if (count < 0) {
83 		return NULL;
84 	} else if (count > 0) {
85 		resources = kzalloc(count * sizeof(struct resource),
86 				    GFP_KERNEL);
87 		if (!resources) {
88 			dev_err(&adev->dev, "No memory for resources\n");
89 			acpi_dev_free_resource_list(&resource_list);
90 			return ERR_PTR(-ENOMEM);
91 		}
92 		count = 0;
93 		list_for_each_entry(rentry, &resource_list, node)
94 			acpi_platform_fill_resource(adev, rentry->res,
95 						    &resources[count++]);
96 
97 		acpi_dev_free_resource_list(&resource_list);
98 	}
99 
100 	memset(&pdevinfo, 0, sizeof(pdevinfo));
101 	/*
102 	 * If the ACPI node has a parent and that parent has a physical device
103 	 * attached to it, that physical device should be the parent of the
104 	 * platform device we are about to create.
105 	 */
106 	pdevinfo.parent = adev->parent ?
107 		acpi_get_first_physical_node(adev->parent) : NULL;
108 	pdevinfo.name = dev_name(&adev->dev);
109 	pdevinfo.id = -1;
110 	pdevinfo.res = resources;
111 	pdevinfo.num_res = count;
112 	pdevinfo.fwnode = acpi_fwnode_handle(adev);
113 	pdevinfo.properties = properties;
114 
115 	if (acpi_dma_supported(adev))
116 		pdevinfo.dma_mask = DMA_BIT_MASK(32);
117 	else
118 		pdevinfo.dma_mask = 0;
119 
120 	pdev = platform_device_register_full(&pdevinfo);
121 	if (IS_ERR(pdev))
122 		dev_err(&adev->dev, "platform device creation failed: %ld\n",
123 			PTR_ERR(pdev));
124 	else {
125 		set_dev_node(&pdev->dev, acpi_get_node(adev->handle));
126 		dev_dbg(&adev->dev, "created platform device %s\n",
127 			dev_name(&pdev->dev));
128 	}
129 
130 	kfree(resources);
131 
132 	return pdev;
133 }
134 EXPORT_SYMBOL_GPL(acpi_create_platform_device);
135