1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * ACPI support for platform bus type.
4 *
5 * Copyright (C) 2012, Intel Corporation
6 * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
7 * Mathias Nyman <mathias.nyman@linux.intel.com>
8 * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
9 */
10
11 #include <linux/acpi.h>
12 #include <linux/device.h>
13 #include <linux/err.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/pci.h>
18 #include <linux/platform_device.h>
19
20 #include "internal.h"
21
22 static const struct acpi_device_id forbidden_id_list[] = {
23 {"ACPI0009", 0}, /* IOxAPIC */
24 {"ACPI000A", 0}, /* IOAPIC */
25 {"PNP0000", 0}, /* PIC */
26 {"PNP0100", 0}, /* Timer */
27 {"PNP0200", 0}, /* AT DMA Controller */
28 {"SMB0001", 0}, /* ACPI SMBUS virtual device */
29 { }
30 };
31
acpi_platform_device_find_by_companion(struct acpi_device * adev)32 static struct platform_device *acpi_platform_device_find_by_companion(struct acpi_device *adev)
33 {
34 struct device *dev;
35
36 dev = bus_find_device_by_acpi_dev(&platform_bus_type, adev);
37 return dev ? to_platform_device(dev) : NULL;
38 }
39
acpi_platform_device_remove_notify(struct notifier_block * nb,unsigned long value,void * arg)40 static int acpi_platform_device_remove_notify(struct notifier_block *nb,
41 unsigned long value, void *arg)
42 {
43 struct acpi_device *adev = arg;
44 struct platform_device *pdev;
45
46 switch (value) {
47 case ACPI_RECONFIG_DEVICE_ADD:
48 /* Nothing to do here */
49 break;
50 case ACPI_RECONFIG_DEVICE_REMOVE:
51 if (!acpi_device_enumerated(adev))
52 break;
53
54 pdev = acpi_platform_device_find_by_companion(adev);
55 if (!pdev)
56 break;
57
58 platform_device_unregister(pdev);
59 put_device(&pdev->dev);
60 break;
61 }
62
63 return NOTIFY_OK;
64 }
65
66 static struct notifier_block acpi_platform_notifier = {
67 .notifier_call = acpi_platform_device_remove_notify,
68 };
69
acpi_platform_fill_resource(struct acpi_device * adev,const struct resource * src,struct resource * dest)70 static void acpi_platform_fill_resource(struct acpi_device *adev,
71 const struct resource *src, struct resource *dest)
72 {
73 struct device *parent;
74
75 *dest = *src;
76
77 /*
78 * If the device has parent we need to take its resources into
79 * account as well because this device might consume part of those.
80 */
81 parent = acpi_get_first_physical_node(acpi_dev_parent(adev));
82 if (parent && dev_is_pci(parent))
83 dest->parent = pci_find_resource(to_pci_dev(parent), dest);
84 }
85
86 /**
87 * acpi_create_platform_device - Create platform device for ACPI device node
88 * @adev: ACPI device node to create a platform device for.
89 * @properties: Optional collection of build-in properties.
90 *
91 * Check if the given @adev can be represented as a platform device and, if
92 * that's the case, create and register a platform device, populate its common
93 * resources and returns a pointer to it. Otherwise, return %NULL.
94 *
95 * Name of the platform device will be the same as @adev's.
96 */
acpi_create_platform_device(struct acpi_device * adev,const struct property_entry * properties)97 struct platform_device *acpi_create_platform_device(struct acpi_device *adev,
98 const struct property_entry *properties)
99 {
100 struct acpi_device *parent = acpi_dev_parent(adev);
101 struct platform_device *pdev = NULL;
102 struct platform_device_info pdevinfo;
103 struct resource_entry *rentry;
104 struct list_head resource_list;
105 struct resource *resources = NULL;
106 int count;
107
108 /* If the ACPI node already has a physical device attached, skip it. */
109 if (adev->physical_node_count)
110 return NULL;
111
112 if (!acpi_match_device_ids(adev, forbidden_id_list))
113 return ERR_PTR(-EINVAL);
114
115 INIT_LIST_HEAD(&resource_list);
116 count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
117 if (count < 0)
118 return NULL;
119 if (count > 0) {
120 resources = kcalloc(count, sizeof(*resources), GFP_KERNEL);
121 if (!resources) {
122 acpi_dev_free_resource_list(&resource_list);
123 return ERR_PTR(-ENOMEM);
124 }
125 count = 0;
126 list_for_each_entry(rentry, &resource_list, node)
127 acpi_platform_fill_resource(adev, rentry->res,
128 &resources[count++]);
129
130 acpi_dev_free_resource_list(&resource_list);
131 }
132
133 memset(&pdevinfo, 0, sizeof(pdevinfo));
134 /*
135 * If the ACPI node has a parent and that parent has a physical device
136 * attached to it, that physical device should be the parent of the
137 * platform device we are about to create.
138 */
139 pdevinfo.parent = parent ? acpi_get_first_physical_node(parent) : NULL;
140 pdevinfo.name = dev_name(&adev->dev);
141 pdevinfo.id = PLATFORM_DEVID_NONE;
142 pdevinfo.res = resources;
143 pdevinfo.num_res = count;
144 pdevinfo.fwnode = acpi_fwnode_handle(adev);
145 pdevinfo.properties = properties;
146
147 if (acpi_dma_supported(adev))
148 pdevinfo.dma_mask = DMA_BIT_MASK(32);
149 else
150 pdevinfo.dma_mask = 0;
151
152 pdev = platform_device_register_full(&pdevinfo);
153 if (IS_ERR(pdev))
154 dev_err(&adev->dev, "platform device creation failed: %ld\n",
155 PTR_ERR(pdev));
156 else {
157 set_dev_node(&pdev->dev, acpi_get_node(adev->handle));
158 dev_dbg(&adev->dev, "created platform device %s\n",
159 dev_name(&pdev->dev));
160 }
161
162 kfree(resources);
163
164 return pdev;
165 }
166 EXPORT_SYMBOL_GPL(acpi_create_platform_device);
167
acpi_platform_init(void)168 void __init acpi_platform_init(void)
169 {
170 acpi_reconfig_notifier_register(&acpi_platform_notifier);
171 }
172