xref: /linux/drivers/acpi/acpi_platform.c (revision f4cdf7ca9a1fdcca413157df19753f388a5a224e)
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/ioport.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/pci.h>
20 #include <linux/platform_device.h>
21 
22 #include "internal.h"
23 
24 /* Exclude devices that have no _CRS resources provided */
25 #define ACPI_ALLOW_WO_RESOURCES		BIT(0)
26 
27 static const struct acpi_device_id forbidden_id_list[] = {
28 	{"ACPI0009", 0},	/* IOxAPIC */
29 	{"ACPI000A", 0},	/* IOAPIC */
30 	{"PNP0000",  0},	/* PIC */
31 	{"PNP0100",  0},	/* Timer */
32 	{"PNP0200",  0},	/* AT DMA Controller */
33 	{ACPI_SMBUS_MS_HID,  ACPI_ALLOW_WO_RESOURCES},	/* ACPI SMBUS virtual device */
34 	{ }
35 };
36 
37 static struct platform_device *acpi_platform_device_find_by_companion(struct acpi_device *adev)
38 {
39 	struct device *dev;
40 
41 	dev = bus_find_device_by_acpi_dev(&platform_bus_type, adev);
42 	return dev ? to_platform_device(dev) : NULL;
43 }
44 
45 static int acpi_platform_device_remove_notify(struct notifier_block *nb,
46 					      unsigned long value, void *arg)
47 {
48 	struct acpi_device *adev = arg;
49 	struct platform_device *pdev;
50 
51 	switch (value) {
52 	case ACPI_RECONFIG_DEVICE_ADD:
53 		/* Nothing to do here */
54 		break;
55 	case ACPI_RECONFIG_DEVICE_REMOVE:
56 		if (!acpi_device_enumerated(adev))
57 			break;
58 
59 		pdev = acpi_platform_device_find_by_companion(adev);
60 		if (!pdev)
61 			break;
62 
63 		platform_device_unregister(pdev);
64 		put_device(&pdev->dev);
65 		break;
66 	}
67 
68 	return NOTIFY_OK;
69 }
70 
71 static struct notifier_block acpi_platform_notifier = {
72 	.notifier_call = acpi_platform_device_remove_notify,
73 };
74 
75 static unsigned int acpi_platform_adjust_resources(struct acpi_device *adev,
76 						   struct resource *new_res,
77 						   struct resource *resources,
78 						   unsigned int count)
79 {
80 	unsigned int i;
81 
82 	if (!(new_res->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
83 		return count;
84 
85 	for (i = 0; i < count; ) {
86 		struct resource *res = &resources[i];
87 
88 		if (resource_type(new_res) != resource_type(res) ||
89 		    !resource_union(new_res, res, new_res)) {
90 			i++;
91 			continue;
92 		}
93 
94 		dev_info(&adev->dev, "%pR expanded due to overlap\n", new_res);
95 		/*
96 		 * Eliminate the previously processed resource that overlapped
97 		 * with the new one because it is not necessary any more.
98 		 */
99 		memmove(res, res + 1, (--count - i) * sizeof(*res));
100 	}
101 
102 	return count;
103 }
104 
105 static void acpi_platform_fill_resource(struct acpi_device *adev,
106 	const struct resource *src, struct resource *dest)
107 {
108 	struct device *parent;
109 
110 	*dest = *src;
111 
112 	/*
113 	 * If the device has parent we need to take its resources into
114 	 * account as well because this device might consume part of those.
115 	 */
116 	parent = acpi_get_first_physical_node(acpi_dev_parent(adev));
117 	if (parent && dev_is_pci(parent))
118 		dest->parent = pci_find_resource(to_pci_dev(parent), dest);
119 }
120 
121 static unsigned int acpi_platform_resource_count(struct acpi_resource *ares, void *data)
122 {
123 	bool *has_resources = data;
124 
125 	*has_resources = true;
126 
127 	return AE_CTRL_TERMINATE;
128 }
129 
130 /**
131  * acpi_create_platform_device - Create platform device for ACPI device node
132  * @adev: ACPI device node to create a platform device for.
133  * @properties: Optional collection of build-in properties.
134  *
135  * Check if the given @adev can be represented as a platform device and, if
136  * that's the case, create and register a platform device, populate its common
137  * resources and returns a pointer to it.  Otherwise, return %NULL.
138  *
139  * Name of the platform device will be the same as @adev's.
140  */
141 struct platform_device *acpi_create_platform_device(struct acpi_device *adev,
142 						    const struct property_entry *properties)
143 {
144 	struct acpi_device *parent = acpi_dev_parent(adev);
145 	struct platform_device *pdev = NULL;
146 	struct platform_device_info pdevinfo;
147 	const struct acpi_device_id *match;
148 	struct resource *resources = NULL;
149 	int count = 0;
150 
151 	/* If the ACPI node already has a physical device attached, skip it. */
152 	if (adev->physical_node_count && !adev->pnp.type.backlight)
153 		return NULL;
154 
155 	match = acpi_match_acpi_device(forbidden_id_list, adev);
156 	if (match) {
157 		if (match->driver_data & ACPI_ALLOW_WO_RESOURCES) {
158 			bool has_resources = false;
159 
160 			acpi_walk_resources(adev->handle, METHOD_NAME__CRS,
161 					    acpi_platform_resource_count, &has_resources);
162 			if (has_resources)
163 				return ERR_PTR(-EINVAL);
164 		} else {
165 			return ERR_PTR(-EINVAL);
166 		}
167 	}
168 
169 	if (adev->device_type == ACPI_BUS_TYPE_DEVICE) {
170 		LIST_HEAD(resource_list);
171 
172 		count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
173 		if (count < 0)
174 			return ERR_PTR(-ENODATA);
175 
176 		if (count > 0) {
177 			struct resource_entry *rentry;
178 
179 			resources = kzalloc_objs(*resources, count);
180 			if (!resources) {
181 				acpi_dev_free_resource_list(&resource_list);
182 				return ERR_PTR(-ENOMEM);
183 			}
184 			count = 0;
185 			list_for_each_entry(rentry, &resource_list, node) {
186 				count = acpi_platform_adjust_resources(adev,
187 								       rentry->res,
188 								       resources,
189 								       count);
190 				acpi_platform_fill_resource(adev, rentry->res,
191 							    &resources[count++]);
192 			}
193 			acpi_dev_free_resource_list(&resource_list);
194 		}
195 	}
196 
197 	memset(&pdevinfo, 0, sizeof(pdevinfo));
198 	/*
199 	 * If the ACPI node has a parent and that parent has a physical device
200 	 * attached to it, that physical device should be the parent of the
201 	 * platform device we are about to create.
202 	 */
203 	pdevinfo.parent = parent ? acpi_get_first_physical_node(parent) : NULL;
204 	pdevinfo.name = dev_name(&adev->dev);
205 	pdevinfo.id = PLATFORM_DEVID_NONE;
206 	pdevinfo.res = resources;
207 	pdevinfo.num_res = count;
208 	pdevinfo.fwnode = acpi_fwnode_handle(adev);
209 	pdevinfo.properties = properties;
210 
211 	if (acpi_dma_supported(adev))
212 		pdevinfo.dma_mask = DMA_BIT_MASK(32);
213 	else
214 		pdevinfo.dma_mask = 0;
215 
216 	pdev = platform_device_register_full(&pdevinfo);
217 	if (IS_ERR(pdev))
218 		dev_err(&adev->dev, "platform device creation failed: %ld\n",
219 			PTR_ERR(pdev));
220 	else {
221 		set_dev_node(&pdev->dev, acpi_get_node(adev->handle));
222 		dev_dbg(&adev->dev, "created platform device %s\n",
223 			dev_name(&pdev->dev));
224 	}
225 
226 	kfree(resources);
227 
228 	return pdev;
229 }
230 EXPORT_SYMBOL_GPL(acpi_create_platform_device);
231 
232 void __init acpi_platform_init(void)
233 {
234 	acpi_reconfig_notifier_register(&acpi_platform_notifier);
235 }
236