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/bits.h>
13#include <linux/device.h>
14#include <linux/err.h>
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/dma-mapping.h>
18#include <linux/pci.h>
19#include <linux/platform_device.h>
20
21#include "internal.h"
22
23/* Exclude devices that have no _CRS resources provided */
24#define ACPI_ALLOW_WO_RESOURCES BIT(0)
25
26static const struct acpi_device_id forbidden_id_list[] = {
27 {"ACPI0009", 0}, /* IOxAPIC */
28 {.id: "ACPI000A", .driver_data: 0}, /* IOAPIC */
29 {.id: "PNP0000", .driver_data: 0}, /* PIC */
30 {.id: "PNP0100", .driver_data: 0}, /* Timer */
31 {.id: "PNP0200", .driver_data: 0}, /* AT DMA Controller */
32 {ACPI_SMBUS_MS_HID, ACPI_ALLOW_WO_RESOURCES}, /* ACPI SMBUS virtual device */
33 { }
34};
35
36static struct platform_device *acpi_platform_device_find_by_companion(struct acpi_device *adev)
37{
38 struct device *dev;
39
40 dev = bus_find_device_by_acpi_dev(bus: &platform_bus_type, adev);
41 return dev ? to_platform_device(dev) : NULL;
42}
43
44static int acpi_platform_device_remove_notify(struct notifier_block *nb,
45 unsigned long value, void *arg)
46{
47 struct acpi_device *adev = arg;
48 struct platform_device *pdev;
49
50 switch (value) {
51 case ACPI_RECONFIG_DEVICE_ADD:
52 /* Nothing to do here */
53 break;
54 case ACPI_RECONFIG_DEVICE_REMOVE:
55 if (!acpi_device_enumerated(adev))
56 break;
57
58 pdev = acpi_platform_device_find_by_companion(adev);
59 if (!pdev)
60 break;
61
62 platform_device_unregister(pdev);
63 put_device(dev: &pdev->dev);
64 break;
65 }
66
67 return NOTIFY_OK;
68}
69
70static struct notifier_block acpi_platform_notifier = {
71 .notifier_call = acpi_platform_device_remove_notify,
72};
73
74static void acpi_platform_fill_resource(struct acpi_device *adev,
75 const struct resource *src, struct resource *dest)
76{
77 struct device *parent;
78
79 *dest = *src;
80
81 /*
82 * If the device has parent we need to take its resources into
83 * account as well because this device might consume part of those.
84 */
85 parent = acpi_get_first_physical_node(adev: acpi_dev_parent(adev));
86 if (parent && dev_is_pci(parent))
87 dest->parent = pci_find_resource(to_pci_dev(parent), res: dest);
88}
89
90static unsigned int acpi_platform_resource_count(struct acpi_resource *ares, void *data)
91{
92 bool *has_resources = data;
93
94 *has_resources = true;
95
96 return AE_CTRL_TERMINATE;
97}
98
99/**
100 * acpi_create_platform_device - Create platform device for ACPI device node
101 * @adev: ACPI device node to create a platform device for.
102 * @properties: Optional collection of build-in properties.
103 *
104 * Check if the given @adev can be represented as a platform device and, if
105 * that's the case, create and register a platform device, populate its common
106 * resources and returns a pointer to it. Otherwise, return %NULL.
107 *
108 * Name of the platform device will be the same as @adev's.
109 */
110struct platform_device *acpi_create_platform_device(struct acpi_device *adev,
111 const struct property_entry *properties)
112{
113 struct acpi_device *parent = acpi_dev_parent(adev);
114 struct platform_device *pdev = NULL;
115 struct platform_device_info pdevinfo;
116 const struct acpi_device_id *match;
117 struct resource_entry *rentry;
118 struct list_head resource_list;
119 struct resource *resources = NULL;
120 int count;
121
122 /* If the ACPI node already has a physical device attached, skip it. */
123 if (adev->physical_node_count)
124 return NULL;
125
126 match = acpi_match_acpi_device(ids: forbidden_id_list, adev);
127 if (match) {
128 if (match->driver_data & ACPI_ALLOW_WO_RESOURCES) {
129 bool has_resources = false;
130
131 acpi_walk_resources(device: adev->handle, METHOD_NAME__CRS,
132 user_function: acpi_platform_resource_count, context: &has_resources);
133 if (has_resources)
134 return ERR_PTR(error: -EINVAL);
135 } else {
136 return ERR_PTR(error: -EINVAL);
137 }
138 }
139
140 INIT_LIST_HEAD(list: &resource_list);
141 count = acpi_dev_get_resources(adev, list: &resource_list, NULL, NULL);
142 if (count < 0)
143 return NULL;
144 if (count > 0) {
145 resources = kcalloc(count, sizeof(*resources), GFP_KERNEL);
146 if (!resources) {
147 acpi_dev_free_resource_list(list: &resource_list);
148 return ERR_PTR(error: -ENOMEM);
149 }
150 count = 0;
151 list_for_each_entry(rentry, &resource_list, node)
152 acpi_platform_fill_resource(adev, src: rentry->res,
153 dest: &resources[count++]);
154
155 acpi_dev_free_resource_list(list: &resource_list);
156 }
157
158 memset(s: &pdevinfo, c: 0, n: sizeof(pdevinfo));
159 /*
160 * If the ACPI node has a parent and that parent has a physical device
161 * attached to it, that physical device should be the parent of the
162 * platform device we are about to create.
163 */
164 pdevinfo.parent = parent ? acpi_get_first_physical_node(adev: parent) : NULL;
165 pdevinfo.name = dev_name(dev: &adev->dev);
166 pdevinfo.id = PLATFORM_DEVID_NONE;
167 pdevinfo.res = resources;
168 pdevinfo.num_res = count;
169 pdevinfo.fwnode = acpi_fwnode_handle(adev);
170 pdevinfo.properties = properties;
171
172 if (acpi_dma_supported(adev))
173 pdevinfo.dma_mask = DMA_BIT_MASK(32);
174 else
175 pdevinfo.dma_mask = 0;
176
177 pdev = platform_device_register_full(pdevinfo: &pdevinfo);
178 if (IS_ERR(ptr: pdev))
179 dev_err(&adev->dev, "platform device creation failed: %ld\n",
180 PTR_ERR(pdev));
181 else {
182 set_dev_node(dev: &pdev->dev, node: acpi_get_node(handle: adev->handle));
183 dev_dbg(&adev->dev, "created platform device %s\n",
184 dev_name(&pdev->dev));
185 }
186
187 kfree(objp: resources);
188
189 return pdev;
190}
191EXPORT_SYMBOL_GPL(acpi_create_platform_device);
192
193void __init acpi_platform_init(void)
194{
195 acpi_reconfig_notifier_register(nb: &acpi_platform_notifier);
196}
197