xref: /openbmc/linux/drivers/pnp/core.c (revision 9b93eb47)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * core.c - contains all core device and protocol registration functions
4  *
5  * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
6  */
7 
8 #include <linux/pnp.h>
9 #include <linux/types.h>
10 #include <linux/list.h>
11 #include <linux/device.h>
12 #include <linux/module.h>
13 #include <linux/mutex.h>
14 #include <linux/init.h>
15 #include <linux/string.h>
16 #include <linux/slab.h>
17 #include <linux/errno.h>
18 #include <linux/dma-mapping.h>
19 
20 #include "base.h"
21 
22 static LIST_HEAD(pnp_protocols);
23 LIST_HEAD(pnp_global);
24 DEFINE_MUTEX(pnp_lock);
25 
26 /*
27  * ACPI or PNPBIOS should tell us about all platform devices, so we can
28  * skip some blind probes.  ISAPNP typically enumerates only plug-in ISA
29  * devices, not built-in things like COM ports.
30  */
31 int pnp_platform_devices;
32 EXPORT_SYMBOL(pnp_platform_devices);
33 
34 void *pnp_alloc(long size)
35 {
36 	void *result;
37 
38 	result = kzalloc(size, GFP_KERNEL);
39 	if (!result) {
40 		printk(KERN_ERR "pnp: Out of Memory\n");
41 		return NULL;
42 	}
43 	return result;
44 }
45 
46 static void pnp_remove_protocol(struct pnp_protocol *protocol)
47 {
48 	mutex_lock(&pnp_lock);
49 	list_del(&protocol->protocol_list);
50 	mutex_unlock(&pnp_lock);
51 }
52 
53 /**
54  * pnp_protocol_register - adds a pnp protocol to the pnp layer
55  * @protocol: pointer to the corresponding pnp_protocol structure
56  *
57  *  Ex protocols: ISAPNP, PNPBIOS, etc
58  */
59 int pnp_register_protocol(struct pnp_protocol *protocol)
60 {
61 	struct list_head *pos;
62 	int nodenum, ret;
63 
64 	INIT_LIST_HEAD(&protocol->devices);
65 	INIT_LIST_HEAD(&protocol->cards);
66 	nodenum = 0;
67 
68 	mutex_lock(&pnp_lock);
69 
70 	/* assign the lowest unused number */
71 	list_for_each(pos, &pnp_protocols) {
72 		struct pnp_protocol *cur = to_pnp_protocol(pos);
73 		if (cur->number == nodenum) {
74 			pos = &pnp_protocols;
75 			nodenum++;
76 		}
77 	}
78 
79 	protocol->number = nodenum;
80 	dev_set_name(&protocol->dev, "pnp%d", nodenum);
81 
82 	list_add_tail(&protocol->protocol_list, &pnp_protocols);
83 
84 	mutex_unlock(&pnp_lock);
85 
86 	ret = device_register(&protocol->dev);
87 	if (ret)
88 		pnp_remove_protocol(protocol);
89 
90 	return ret;
91 }
92 
93 /**
94  * pnp_protocol_unregister - removes a pnp protocol from the pnp layer
95  * @protocol: pointer to the corresponding pnp_protocol structure
96  */
97 void pnp_unregister_protocol(struct pnp_protocol *protocol)
98 {
99 	pnp_remove_protocol(protocol);
100 	device_unregister(&protocol->dev);
101 }
102 
103 static void pnp_free_ids(struct pnp_dev *dev)
104 {
105 	struct pnp_id *id;
106 	struct pnp_id *next;
107 
108 	id = dev->id;
109 	while (id) {
110 		next = id->next;
111 		kfree(id);
112 		id = next;
113 	}
114 }
115 
116 void pnp_free_resource(struct pnp_resource *pnp_res)
117 {
118 	list_del(&pnp_res->list);
119 	kfree(pnp_res);
120 }
121 
122 void pnp_free_resources(struct pnp_dev *dev)
123 {
124 	struct pnp_resource *pnp_res, *tmp;
125 
126 	list_for_each_entry_safe(pnp_res, tmp, &dev->resources, list) {
127 		pnp_free_resource(pnp_res);
128 	}
129 }
130 
131 static void pnp_release_device(struct device *dmdev)
132 {
133 	struct pnp_dev *dev = to_pnp_dev(dmdev);
134 
135 	pnp_free_ids(dev);
136 	pnp_free_resources(dev);
137 	pnp_free_options(dev);
138 	kfree(dev);
139 }
140 
141 struct pnp_dev *pnp_alloc_dev(struct pnp_protocol *protocol, int id,
142 			      const char *pnpid)
143 {
144 	struct pnp_dev *dev;
145 	struct pnp_id *dev_id;
146 
147 	dev = kzalloc(sizeof(struct pnp_dev), GFP_KERNEL);
148 	if (!dev)
149 		return NULL;
150 
151 	INIT_LIST_HEAD(&dev->resources);
152 	INIT_LIST_HEAD(&dev->options);
153 	dev->protocol = protocol;
154 	dev->number = id;
155 	dev->dma_mask = DMA_BIT_MASK(24);
156 
157 	dev->dev.parent = &dev->protocol->dev;
158 	dev->dev.bus = &pnp_bus_type;
159 	dev->dev.dma_mask = &dev->dma_mask;
160 	dev->dev.coherent_dma_mask = dev->dma_mask;
161 	dev->dev.release = &pnp_release_device;
162 
163 	dev_set_name(&dev->dev, "%02x:%02x", dev->protocol->number, dev->number);
164 
165 	dev_id = pnp_add_id(dev, pnpid);
166 	if (!dev_id) {
167 		kfree(dev);
168 		return NULL;
169 	}
170 
171 	return dev;
172 }
173 
174 static void pnp_delist_device(struct pnp_dev *dev)
175 {
176 	mutex_lock(&pnp_lock);
177 	list_del(&dev->global_list);
178 	list_del(&dev->protocol_list);
179 	mutex_unlock(&pnp_lock);
180 }
181 
182 int __pnp_add_device(struct pnp_dev *dev)
183 {
184 	int ret;
185 
186 	pnp_fixup_device(dev);
187 	dev->status = PNP_READY;
188 
189 	mutex_lock(&pnp_lock);
190 
191 	list_add_tail(&dev->global_list, &pnp_global);
192 	list_add_tail(&dev->protocol_list, &dev->protocol->devices);
193 
194 	mutex_unlock(&pnp_lock);
195 
196 	ret = device_register(&dev->dev);
197 	if (ret)
198 		pnp_delist_device(dev);
199 	else if (dev->protocol->can_wakeup)
200 		device_set_wakeup_capable(&dev->dev,
201 				dev->protocol->can_wakeup(dev));
202 
203 	return ret;
204 }
205 
206 /*
207  * pnp_add_device - adds a pnp device to the pnp layer
208  * @dev: pointer to dev to add
209  *
210  *  adds to driver model, name database, fixups, interface, etc.
211  */
212 int pnp_add_device(struct pnp_dev *dev)
213 {
214 	int ret;
215 	char buf[128];
216 	int len = 0;
217 	struct pnp_id *id;
218 
219 	if (dev->card)
220 		return -EINVAL;
221 
222 	ret = __pnp_add_device(dev);
223 	if (ret)
224 		return ret;
225 
226 	buf[0] = '\0';
227 	for (id = dev->id; id; id = id->next)
228 		len += scnprintf(buf + len, sizeof(buf) - len, " %s", id->id);
229 
230 	dev_printk(KERN_DEBUG, &dev->dev, "%s device, IDs%s (%s)\n",
231 		   dev->protocol->name, buf,
232 		   dev->active ? "active" : "disabled");
233 	return 0;
234 }
235 
236 void __pnp_remove_device(struct pnp_dev *dev)
237 {
238 	pnp_delist_device(dev);
239 	device_unregister(&dev->dev);
240 }
241 
242 static int __init pnp_init(void)
243 {
244 	return bus_register(&pnp_bus_type);
245 }
246 
247 subsys_initcall(pnp_init);
248 
249 int pnp_debug;
250 
251 #if defined(CONFIG_PNP_DEBUG_MESSAGES)
252 module_param_named(debug, pnp_debug, int, 0644);
253 #endif
254