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(&protocol->protocol_list);
38	mutex_unlock(&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(&protocol->devices);
53	INIT_LIST_HEAD(&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(&protocol->dev, "pnp%d", nodenum);
69
70	list_add_tail(&protocol->protocol_list, &pnp_protocols);
71
72	mutex_unlock(&pnp_lock);
73
74	ret = device_register(&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(&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(id);
100		id = next;
101	}
102}
103
104void pnp_free_resource(struct pnp_resource *pnp_res)
105{
106	list_del(&pnp_res->list);
107	kfree(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(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(sizeof(struct pnp_dev), GFP_KERNEL);
136	if (!dev)
137		return NULL;
138
139	INIT_LIST_HEAD(&dev->resources);
140	INIT_LIST_HEAD(&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, pnpid);
152	if (!dev_id) {
153		kfree(dev);
154		return NULL;
155	}
156
157	dev_set_name(&dev->dev, "%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(&dev->global_list);
166	list_del(&dev->protocol_list);
167	mutex_unlock(&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(&dev->global_list, &pnp_global);
180	list_add_tail(&dev->protocol_list, &dev->protocol->devices);
181
182	mutex_unlock(&pnp_lock);
183
184	ret = device_register(&dev->dev);
185	if (ret)
186		pnp_delist_device(dev);
187	else if (dev->protocol->can_wakeup)
188		device_set_wakeup_capable(&dev->dev,
189				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 + len, sizeof(buf) - len, " %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);
227}
228
229static int __init pnp_init(void)
230{
231	return bus_register(&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