xref: /openbmc/linux/drivers/pnp/driver.c (revision 643d1f7f)
1 /*
2  * driver.c - device id matching, driver model, etc.
3  *
4  * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
5  */
6 
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"
14 
15 static int compare_func(const char *ida, const char *idb)
16 {
17 	int i;
18 
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;
24 	}
25 	return 1;
26 }
27 
28 int compare_pnp_id(struct pnp_id *pos, const char *id)
29 {
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;
39 	}
40 	return 0;
41 }
42 
43 static const struct pnp_device_id *match_device(struct pnp_driver *drv,
44 						struct pnp_dev *dev)
45 {
46 	const struct pnp_device_id *drv_id = drv->id_table;
47 
48 	if (!drv_id)
49 		return NULL;
50 
51 	while (*drv_id->id) {
52 		if (compare_pnp_id(dev->id, drv_id->id))
53 			return drv_id;
54 		drv_id++;
55 	}
56 	return NULL;
57 }
58 
59 int pnp_device_attach(struct pnp_dev *pnp_dev)
60 {
61 	spin_lock(&pnp_lock);
62 	if (pnp_dev->status != PNP_READY) {
63 		spin_unlock(&pnp_lock);
64 		return -EBUSY;
65 	}
66 	pnp_dev->status = PNP_ATTACHED;
67 	spin_unlock(&pnp_lock);
68 	return 0;
69 }
70 
71 void pnp_device_detach(struct pnp_dev *pnp_dev)
72 {
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);
78 }
79 
80 static int pnp_device_probe(struct device *dev)
81 {
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);
88 
89 	error = pnp_device_attach(pnp_dev);
90 	if (error < 0)
91 		return error;
92 
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;
98 		}
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;
104 	}
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);
110 	}
111 	if (error >= 0) {
112 		pnp_dev->driver = pnp_drv;
113 		error = 0;
114 	} else
115 		goto fail;
116 
117 	dev_dbg(dev, "driver attached\n");
118 	return error;
119 
120 fail:
121 	pnp_device_detach(pnp_dev);
122 	return error;
123 }
124 
125 static int pnp_device_remove(struct device *dev)
126 {
127 	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
128 	struct pnp_driver *drv = pnp_dev->driver;
129 
130 	if (drv) {
131 		if (drv->remove)
132 			drv->remove(pnp_dev);
133 		pnp_dev->driver = NULL;
134 	}
135 	pnp_device_detach(pnp_dev);
136 	return 0;
137 }
138 
139 static int pnp_bus_match(struct device *dev, struct device_driver *drv)
140 {
141 	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
142 	struct pnp_driver *pnp_drv = to_pnp_driver(drv);
143 
144 	if (match_device(pnp_drv, pnp_dev) == NULL)
145 		return 0;
146 	return 1;
147 }
148 
149 static int pnp_bus_suspend(struct device *dev, pm_message_t state)
150 {
151 	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
152 	struct pnp_driver *pnp_drv = pnp_dev->driver;
153 	int error;
154 
155 	if (!pnp_drv)
156 		return 0;
157 
158 	if (pnp_drv->suspend) {
159 		error = pnp_drv->suspend(pnp_dev, state);
160 		if (error)
161 			return error;
162 	}
163 
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;
169 	}
170 
171 	if (pnp_dev->protocol && pnp_dev->protocol->suspend)
172 		pnp_dev->protocol->suspend(pnp_dev, state);
173 	return 0;
174 }
175 
176 static int pnp_bus_resume(struct device *dev)
177 {
178 	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
179 	struct pnp_driver *pnp_drv = pnp_dev->driver;
180 	int error;
181 
182 	if (!pnp_drv)
183 		return 0;
184 
185 	if (pnp_dev->protocol && pnp_dev->protocol->resume)
186 		pnp_dev->protocol->resume(pnp_dev);
187 
188 	if (!(pnp_drv->flags & PNP_DRIVER_RES_DO_NOT_CHANGE)) {
189 		error = pnp_start_dev(pnp_dev);
190 		if (error)
191 			return error;
192 	}
193 
194 	if (pnp_drv->resume)
195 		return pnp_drv->resume(pnp_dev);
196 
197 	return 0;
198 }
199 
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,
207 };
208 
209 int pnp_register_driver(struct pnp_driver *drv)
210 {
211 	pnp_dbg("the driver '%s' has been registered", drv->name);
212 
213 	drv->driver.name = drv->name;
214 	drv->driver.bus = &pnp_bus_type;
215 
216 	return driver_register(&drv->driver);
217 }
218 
219 void pnp_unregister_driver(struct pnp_driver *drv)
220 {
221 	driver_unregister(&drv->driver);
222 	pnp_dbg("the driver '%s' has been unregistered", drv->name);
223 }
224 
225 /**
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
229  */
230 int pnp_add_id(struct pnp_id *id, struct pnp_dev *dev)
231 {
232 	struct pnp_id *ptr;
233 
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;
243 }
244 
245 EXPORT_SYMBOL(pnp_register_driver);
246 EXPORT_SYMBOL(pnp_unregister_driver);
247 EXPORT_SYMBOL(pnp_device_attach);
248 EXPORT_SYMBOL(pnp_device_detach);
249