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
22static LIST_HEAD(pnp_protocols);
23LIST_HEAD(pnp_global);
24DEFINE_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 */
31int pnp_platform_devices;
32EXPORT_SYMBOL(pnp_platform_devices);
33
34static void pnp_remove_protocol(struct pnp_protocol *protocol)
35{
36 mutex_lock(&pnp_lock);
37 list_del(entry: &protocol->protocol_list);
38 mutex_unlock(lock: &pnp_lock);
39}
40
41/**
42 * pnp_register_protocol - adds a pnp protocol to the pnp layer
43 * @protocol: pointer to the corresponding pnp_protocol structure
44 *
45 * Ex protocols: ISAPNP, PNPBIOS, etc
46 */
47int pnp_register_protocol(struct pnp_protocol *protocol)
48{
49 struct list_head *pos;
50 int nodenum, ret;
51
52 INIT_LIST_HEAD(list: &protocol->devices);
53 INIT_LIST_HEAD(list: &protocol->cards);
54 nodenum = 0;
55
56 mutex_lock(&pnp_lock);
57
58 /* assign the lowest unused number */
59 list_for_each(pos, &pnp_protocols) {
60 struct pnp_protocol *cur = to_pnp_protocol(pos);
61 if (cur->number == nodenum) {
62 pos = &pnp_protocols;
63 nodenum++;
64 }
65 }
66
67 protocol->number = nodenum;
68 dev_set_name(dev: &protocol->dev, name: "pnp%d", nodenum);
69
70 list_add_tail(new: &protocol->protocol_list, head: &pnp_protocols);
71
72 mutex_unlock(lock: &pnp_lock);
73
74 ret = device_register(dev: &protocol->dev);
75 if (ret)
76 pnp_remove_protocol(protocol);
77
78 return ret;
79}
80
81/**
82 * pnp_unregister_protocol - removes a pnp protocol from the pnp layer
83 * @protocol: pointer to the corresponding pnp_protocol structure
84 */
85void pnp_unregister_protocol(struct pnp_protocol *protocol)
86{
87 pnp_remove_protocol(protocol);
88 device_unregister(dev: &protocol->dev);
89}
90
91static void pnp_free_ids(struct pnp_dev *dev)
92{
93 struct pnp_id *id;
94 struct pnp_id *next;
95
96 id = dev->id;
97 while (id) {
98 next = id->next;
99 kfree(objp: id);
100 id = next;
101 }
102}
103
104void pnp_free_resource(struct pnp_resource *pnp_res)
105{
106 list_del(entry: &pnp_res->list);
107 kfree(objp: pnp_res);
108}
109
110void pnp_free_resources(struct pnp_dev *dev)
111{
112 struct pnp_resource *pnp_res, *tmp;
113
114 list_for_each_entry_safe(pnp_res, tmp, &dev->resources, list) {
115 pnp_free_resource(pnp_res);
116 }
117}
118
119static void pnp_release_device(struct device *dmdev)
120{
121 struct pnp_dev *dev = to_pnp_dev(dmdev);
122
123 pnp_free_ids(dev);
124 pnp_free_resources(dev);
125 pnp_free_options(dev);
126 kfree(objp: dev);
127}
128
129struct pnp_dev *pnp_alloc_dev(struct pnp_protocol *protocol, int id,
130 const char *pnpid)
131{
132 struct pnp_dev *dev;
133 struct pnp_id *dev_id;
134
135 dev = kzalloc(size: sizeof(struct pnp_dev), GFP_KERNEL);
136 if (!dev)
137 return NULL;
138
139 INIT_LIST_HEAD(list: &dev->resources);
140 INIT_LIST_HEAD(list: &dev->options);
141 dev->protocol = protocol;
142 dev->number = id;
143 dev->dma_mask = DMA_BIT_MASK(24);
144
145 dev->dev.parent = &dev->protocol->dev;
146 dev->dev.bus = &pnp_bus_type;
147 dev->dev.dma_mask = &dev->dma_mask;
148 dev->dev.coherent_dma_mask = dev->dma_mask;
149 dev->dev.release = &pnp_release_device;
150
151 dev_id = pnp_add_id(dev, id: pnpid);
152 if (!dev_id) {
153 kfree(objp: dev);
154 return NULL;
155 }
156
157 dev_set_name(dev: &dev->dev, name: "%02x:%02x", dev->protocol->number, dev->number);
158
159 return dev;
160}
161
162static void pnp_delist_device(struct pnp_dev *dev)
163{
164 mutex_lock(&pnp_lock);
165 list_del(entry: &dev->global_list);
166 list_del(entry: &dev->protocol_list);
167 mutex_unlock(lock: &pnp_lock);
168}
169
170int __pnp_add_device(struct pnp_dev *dev)
171{
172 int ret;
173
174 pnp_fixup_device(dev);
175 dev->status = PNP_READY;
176
177 mutex_lock(&pnp_lock);
178
179 list_add_tail(new: &dev->global_list, head: &pnp_global);
180 list_add_tail(new: &dev->protocol_list, head: &dev->protocol->devices);
181
182 mutex_unlock(lock: &pnp_lock);
183
184 ret = device_register(dev: &dev->dev);
185 if (ret)
186 pnp_delist_device(dev);
187 else if (dev->protocol->can_wakeup)
188 device_set_wakeup_capable(dev: &dev->dev,
189 capable: dev->protocol->can_wakeup(dev));
190
191 return ret;
192}
193
194/*
195 * pnp_add_device - adds a pnp device to the pnp layer
196 * @dev: pointer to dev to add
197 *
198 * adds to driver model, name database, fixups, interface, etc.
199 */
200int pnp_add_device(struct pnp_dev *dev)
201{
202 int ret;
203 char buf[128];
204 int len = 0;
205 struct pnp_id *id;
206
207 if (dev->card)
208 return -EINVAL;
209
210 ret = __pnp_add_device(dev);
211 if (ret)
212 return ret;
213
214 buf[0] = '\0';
215 for (id = dev->id; id; id = id->next)
216 len += scnprintf(buf: buf + len, size: sizeof(buf) - len, fmt: " %s", id->id);
217
218 dev_dbg(&dev->dev, "%s device, IDs%s (%s)\n", dev->protocol->name, buf,
219 dev->active ? "active" : "disabled");
220 return 0;
221}
222
223void __pnp_remove_device(struct pnp_dev *dev)
224{
225 pnp_delist_device(dev);
226 device_unregister(dev: &dev->dev);
227}
228
229static int __init pnp_init(void)
230{
231 return bus_register(bus: &pnp_bus_type);
232}
233
234subsys_initcall(pnp_init);
235
236int pnp_debug;
237
238#if defined(CONFIG_PNP_DEBUG_MESSAGES)
239module_param_named(debug, pnp_debug, int, 0644);
240#endif
241

source code of linux/drivers/pnp/core.c