core.c

  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
 81static void pnp_free_ids(struct pnp_dev *dev)
 82{
 83	struct pnp_id *id;
 84	struct pnp_id *next;
 85
 86	id = dev->id;
 87	while (id) {
 88		next = id->next;
 89		kfree(id);
 90		id = next;
 91	}
 92}
 93
 94void pnp_free_resource(struct pnp_resource *pnp_res)
 95{
 96	list_del(&pnp_res->list);
 97	kfree(pnp_res);
 98}
 99
100void pnp_free_resources(struct pnp_dev *dev)
101{
102	struct pnp_resource *pnp_res, *tmp;
103
104	list_for_each_entry_safe(pnp_res, tmp, &dev->resources, list) {
105		pnp_free_resource(pnp_res);
106	}
107}
108
109static void pnp_release_device(struct device *dmdev)
110{
111	struct pnp_dev *dev = to_pnp_dev(dmdev);
112
113	pnp_free_ids(dev);
114	pnp_free_resources(dev);
115	pnp_free_options(dev);
116	kfree(dev);
117}
118
119struct pnp_dev *pnp_alloc_dev(struct pnp_protocol *protocol, int id,
120			      const char *pnpid)
121{
122	struct pnp_dev *dev;
123	struct pnp_id *dev_id;
124
125	dev = kzalloc(sizeof(struct pnp_dev), GFP_KERNEL);
126	if (!dev)
127		return NULL;
128
129	INIT_LIST_HEAD(&dev->resources);
130	INIT_LIST_HEAD(&dev->options);
131	dev->protocol = protocol;
132	dev->number = id;
133	dev->dma_mask = DMA_BIT_MASK(24);
134
135	dev->dev.parent = &dev->protocol->dev;
136	dev->dev.bus = &pnp_bus_type;
137	dev->dev.dma_mask = &dev->dma_mask;
138	dev->dev.coherent_dma_mask = dev->dma_mask;
139	dev->dev.release = &pnp_release_device;
140
141	dev_id = pnp_add_id(dev, pnpid);
142	if (!dev_id) {
143		kfree(dev);
144		return NULL;
145	}
146
147	dev_set_name(&dev->dev, "%02x:%02x", dev->protocol->number, dev->number);
148
149	return dev;
150}
151
152static void pnp_delist_device(struct pnp_dev *dev)
153{
154	mutex_lock(&pnp_lock);
155	list_del(&dev->global_list);
156	list_del(&dev->protocol_list);
157	mutex_unlock(&pnp_lock);
158}
159
160int __pnp_add_device(struct pnp_dev *dev)
161{
162	int ret;
163
164	pnp_fixup_device(dev);
165	dev->status = PNP_READY;
166
167	mutex_lock(&pnp_lock);
168
169	list_add_tail(&dev->global_list, &pnp_global);
170	list_add_tail(&dev->protocol_list, &dev->protocol->devices);
171
172	mutex_unlock(&pnp_lock);
173
174	ret = device_register(&dev->dev);
175	if (ret)
176		pnp_delist_device(dev);
177	else if (dev->protocol->can_wakeup)
178		device_set_wakeup_capable(&dev->dev,
179				dev->protocol->can_wakeup(dev));
180
181	return ret;
182}
183
184/*
185 * pnp_add_device - adds a pnp device to the pnp layer
186 * @dev: pointer to dev to add
187 *
188 *  adds to driver model, name database, fixups, interface, etc.
189 */
190int pnp_add_device(struct pnp_dev *dev)
191{
192	int ret;
193	char buf[128];
194	int len = 0;
195	struct pnp_id *id;
196
197	if (dev->card)
198		return -EINVAL;
199
200	ret = __pnp_add_device(dev);
201	if (ret)
202		return ret;
203
204	buf[0] = '\0';
205	for (id = dev->id; id; id = id->next)
206		len += scnprintf(buf + len, sizeof(buf) - len, " %s", id->id);
207
208	dev_dbg(&dev->dev, "%s device, IDs%s (%s)\n", dev->protocol->name, buf,
209		dev->active ? "active" : "disabled");
210	return 0;
211}
212
213static int __init pnp_init(void)
214{
215	return bus_register(&pnp_bus_type);
216}
217
218subsys_initcall(pnp_init);
219
220int pnp_debug;
221
222#if defined(CONFIG_PNP_DEBUG_MESSAGES)
223module_param_named(debug, pnp_debug, int, 0644);
224#endif