V4L/DVB (6621): tda827x: fix NULL pointer dereference during tda827x_probe_version
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / pnp / driver.c
bloba262762c5b8836e0dc5091317e43359b67443fc9
1 /*
2 * driver.c - device id matching, driver model, etc.
4 * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
5 */
7 #include <linux/string.h>
8 #include <linux/list.h>
9 #include <linux/module.h>
10 #include <linux/ctype.h>
11 #include <linux/slab.h>
12 #include <linux/pnp.h>
13 #include "base.h"
15 static int compare_func(const char *ida, const char *idb)
17 int i;
19 /* we only need to compare the last 4 chars */
20 for (i = 3; i < 7; i++) {
21 if (ida[i] != 'X' &&
22 idb[i] != 'X' && toupper(ida[i]) != toupper(idb[i]))
23 return 0;
25 return 1;
28 int compare_pnp_id(struct pnp_id *pos, const char *id)
30 if (!pos || !id || (strlen(id) != 7))
31 return 0;
32 if (memcmp(id, "ANYDEVS", 7) == 0)
33 return 1;
34 while (pos) {
35 if (memcmp(pos->id, id, 3) == 0)
36 if (compare_func(pos->id, id) == 1)
37 return 1;
38 pos = pos->next;
40 return 0;
43 static const struct pnp_device_id *match_device(struct pnp_driver *drv,
44 struct pnp_dev *dev)
46 const struct pnp_device_id *drv_id = drv->id_table;
48 if (!drv_id)
49 return NULL;
51 while (*drv_id->id) {
52 if (compare_pnp_id(dev->id, drv_id->id))
53 return drv_id;
54 drv_id++;
56 return NULL;
59 int pnp_device_attach(struct pnp_dev *pnp_dev)
61 spin_lock(&pnp_lock);
62 if (pnp_dev->status != PNP_READY) {
63 spin_unlock(&pnp_lock);
64 return -EBUSY;
66 pnp_dev->status = PNP_ATTACHED;
67 spin_unlock(&pnp_lock);
68 return 0;
71 void pnp_device_detach(struct pnp_dev *pnp_dev)
73 spin_lock(&pnp_lock);
74 if (pnp_dev->status == PNP_ATTACHED)
75 pnp_dev->status = PNP_READY;
76 spin_unlock(&pnp_lock);
77 pnp_disable_dev(pnp_dev);
80 static int pnp_device_probe(struct device *dev)
82 int error;
83 struct pnp_driver *pnp_drv;
84 struct pnp_dev *pnp_dev;
85 const struct pnp_device_id *dev_id = NULL;
86 pnp_dev = to_pnp_dev(dev);
87 pnp_drv = to_pnp_driver(dev->driver);
89 error = pnp_device_attach(pnp_dev);
90 if (error < 0)
91 return error;
93 if (pnp_dev->active == 0) {
94 if (!(pnp_drv->flags & PNP_DRIVER_RES_DO_NOT_CHANGE)) {
95 error = pnp_activate_dev(pnp_dev);
96 if (error < 0)
97 return error;
99 } else if ((pnp_drv->flags & PNP_DRIVER_RES_DISABLE)
100 == PNP_DRIVER_RES_DISABLE) {
101 error = pnp_disable_dev(pnp_dev);
102 if (error < 0)
103 return error;
105 error = 0;
106 if (pnp_drv->probe) {
107 dev_id = match_device(pnp_drv, pnp_dev);
108 if (dev_id != NULL)
109 error = pnp_drv->probe(pnp_dev, dev_id);
111 if (error >= 0) {
112 pnp_dev->driver = pnp_drv;
113 error = 0;
114 } else
115 goto fail;
117 dev_dbg(dev, "driver attached\n");
118 return error;
120 fail:
121 pnp_device_detach(pnp_dev);
122 return error;
125 static int pnp_device_remove(struct device *dev)
127 struct pnp_dev *pnp_dev = to_pnp_dev(dev);
128 struct pnp_driver *drv = pnp_dev->driver;
130 if (drv) {
131 if (drv->remove)
132 drv->remove(pnp_dev);
133 pnp_dev->driver = NULL;
135 pnp_device_detach(pnp_dev);
136 return 0;
139 static int pnp_bus_match(struct device *dev, struct device_driver *drv)
141 struct pnp_dev *pnp_dev = to_pnp_dev(dev);
142 struct pnp_driver *pnp_drv = to_pnp_driver(drv);
144 if (match_device(pnp_drv, pnp_dev) == NULL)
145 return 0;
146 return 1;
149 static int pnp_bus_suspend(struct device *dev, pm_message_t state)
151 struct pnp_dev *pnp_dev = to_pnp_dev(dev);
152 struct pnp_driver *pnp_drv = pnp_dev->driver;
153 int error;
155 if (!pnp_drv)
156 return 0;
158 if (pnp_drv->suspend) {
159 error = pnp_drv->suspend(pnp_dev, state);
160 if (error)
161 return error;
164 if (!(pnp_drv->flags & PNP_DRIVER_RES_DO_NOT_CHANGE) &&
165 pnp_can_disable(pnp_dev)) {
166 error = pnp_stop_dev(pnp_dev);
167 if (error)
168 return error;
171 if (pnp_dev->protocol && pnp_dev->protocol->suspend)
172 pnp_dev->protocol->suspend(pnp_dev, state);
173 return 0;
176 static int pnp_bus_resume(struct device *dev)
178 struct pnp_dev *pnp_dev = to_pnp_dev(dev);
179 struct pnp_driver *pnp_drv = pnp_dev->driver;
180 int error;
182 if (!pnp_drv)
183 return 0;
185 if (pnp_dev->protocol && pnp_dev->protocol->resume)
186 pnp_dev->protocol->resume(pnp_dev);
188 if (!(pnp_drv->flags & PNP_DRIVER_RES_DO_NOT_CHANGE)) {
189 error = pnp_start_dev(pnp_dev);
190 if (error)
191 return error;
194 if (pnp_drv->resume)
195 return pnp_drv->resume(pnp_dev);
197 return 0;
200 struct bus_type pnp_bus_type = {
201 .name = "pnp",
202 .match = pnp_bus_match,
203 .probe = pnp_device_probe,
204 .remove = pnp_device_remove,
205 .suspend = pnp_bus_suspend,
206 .resume = pnp_bus_resume,
209 int pnp_register_driver(struct pnp_driver *drv)
211 pnp_dbg("the driver '%s' has been registered", drv->name);
213 drv->driver.name = drv->name;
214 drv->driver.bus = &pnp_bus_type;
216 return driver_register(&drv->driver);
219 void pnp_unregister_driver(struct pnp_driver *drv)
221 driver_unregister(&drv->driver);
222 pnp_dbg("the driver '%s' has been unregistered", drv->name);
226 * pnp_add_id - adds an EISA id to the specified device
227 * @id: pointer to a pnp_id structure
228 * @dev: pointer to the desired device
230 int pnp_add_id(struct pnp_id *id, struct pnp_dev *dev)
232 struct pnp_id *ptr;
234 id->next = NULL;
235 ptr = dev->id;
236 while (ptr && ptr->next)
237 ptr = ptr->next;
238 if (ptr)
239 ptr->next = id;
240 else
241 dev->id = id;
242 return 0;
245 EXPORT_SYMBOL(pnp_register_driver);
246 EXPORT_SYMBOL(pnp_unregister_driver);
247 EXPORT_SYMBOL(pnp_device_attach);
248 EXPORT_SYMBOL(pnp_device_detach);