1// SPDX-License-Identifier: GPL-2.0
2/*
3 * driver.c - device id matching, driver model, etc.
4 *
5 * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
6 */
7
8#include <linux/string.h>
9#include <linux/list.h>
10#include <linux/module.h>
11#include <linux/ctype.h>
12#include <linux/slab.h>
13#include <linux/pnp.h>
14#include "base.h"
15
16static int compare_func(const char *ida, const char *idb)
17{
18	int i;
19
20	/* we only need to compare the last 4 chars */
21	for (i = 3; i < 7; i++) {
22		if (ida[i] != 'X' &&
23		    idb[i] != 'X' && toupper(ida[i]) != toupper(idb[i]))
24			return 0;
25	}
26	return 1;
27}
28
29int compare_pnp_id(struct pnp_id *pos, const char *id)
30{
31	if (!pos || !id || (strlen(id) != 7))
32		return 0;
33	if (memcmp(id, "ANYDEVS", 7) == 0)
34		return 1;
35	while (pos) {
36		if (memcmp(pos->id, id, 3) == 0)
37			if (compare_func(pos->id, id) == 1)
38				return 1;
39		pos = pos->next;
40	}
41	return 0;
42}
43
44static const struct pnp_device_id *match_device(struct pnp_driver *drv,
45						struct pnp_dev *dev)
46{
47	const struct pnp_device_id *drv_id = drv->id_table;
48
49	if (!drv_id)
50		return NULL;
51
52	while (*drv_id->id) {
53		if (compare_pnp_id(dev->id, drv_id->id))
54			return drv_id;
55		drv_id++;
56	}
57	return NULL;
58}
59
60int pnp_device_attach(struct pnp_dev *pnp_dev)
61{
62	mutex_lock(&pnp_lock);
63	if (pnp_dev->status != PNP_READY) {
64		mutex_unlock(&pnp_lock);
65		return -EBUSY;
66	}
67	pnp_dev->status = PNP_ATTACHED;
68	mutex_unlock(&pnp_lock);
69	return 0;
70}
71EXPORT_SYMBOL(pnp_device_attach);
72
73void pnp_device_detach(struct pnp_dev *pnp_dev)
74{
75	mutex_lock(&pnp_lock);
76	if (pnp_dev->status == PNP_ATTACHED)
77		pnp_dev->status = PNP_READY;
78	mutex_unlock(&pnp_lock);
79}
80EXPORT_SYMBOL(pnp_device_detach);
81
82static int pnp_device_probe(struct device *dev)
83{
84	int error;
85	struct pnp_driver *pnp_drv;
86	struct pnp_dev *pnp_dev;
87	const struct pnp_device_id *dev_id = NULL;
88	pnp_dev = to_pnp_dev(dev);
89	pnp_drv = to_pnp_driver(dev->driver);
90
91	error = pnp_device_attach(pnp_dev);
92	if (error < 0)
93		return error;
94
95	if (pnp_dev->active == 0) {
96		if (!(pnp_drv->flags & PNP_DRIVER_RES_DO_NOT_CHANGE)) {
97			error = pnp_activate_dev(pnp_dev);
98			if (error < 0)
99				return error;
100		}
101	} else if ((pnp_drv->flags & PNP_DRIVER_RES_DISABLE)
102		   == PNP_DRIVER_RES_DISABLE) {
103		error = pnp_disable_dev(pnp_dev);
104		if (error < 0)
105			return error;
106	}
107	error = 0;
108	if (pnp_drv->probe) {
109		dev_id = match_device(pnp_drv, pnp_dev);
110		if (dev_id != NULL)
111			error = pnp_drv->probe(pnp_dev, dev_id);
112	}
113	if (error >= 0) {
114		pnp_dev->driver = pnp_drv;
115		error = 0;
116	} else
117		goto fail;
118
119	return error;
120
121fail:
122	pnp_device_detach(pnp_dev);
123	return error;
124}
125
126static void pnp_device_remove(struct device *dev)
127{
128	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
129	struct pnp_driver *drv = pnp_dev->driver;
130
131	if (drv) {
132		if (drv->remove)
133			drv->remove(pnp_dev);
134		pnp_dev->driver = NULL;
135	}
136
137	if (pnp_dev->active &&
138	    (!drv || !(drv->flags & PNP_DRIVER_RES_DO_NOT_CHANGE)))
139		pnp_disable_dev(pnp_dev);
140
141	pnp_device_detach(pnp_dev);
142}
143
144static void pnp_device_shutdown(struct device *dev)
145{
146	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
147	struct pnp_driver *drv = pnp_dev->driver;
148
149	if (drv && drv->shutdown)
150		drv->shutdown(pnp_dev);
151}
152
153static int pnp_bus_match(struct device *dev, struct device_driver *drv)
154{
155	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
156	struct pnp_driver *pnp_drv = to_pnp_driver(drv);
157
158	if (match_device(pnp_drv, pnp_dev) == NULL)
159		return 0;
160	return 1;
161}
162
163static int __pnp_bus_suspend(struct device *dev, pm_message_t state)
164{
165	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
166	struct pnp_driver *pnp_drv = pnp_dev->driver;
167	int error;
168
169	if (!pnp_drv)
170		return 0;
171
172	if (pnp_drv->driver.pm && pnp_drv->driver.pm->suspend) {
173		error = pnp_drv->driver.pm->suspend(dev);
174		suspend_report_result(dev, pnp_drv->driver.pm->suspend, error);
175		if (error)
176			return error;
177	}
178
179	if (pnp_drv->suspend) {
180		error = pnp_drv->suspend(pnp_dev, state);
181		if (error)
182			return error;
183	}
184
185	/* can_write is necessary to be able to re-start the device on resume */
186	if (pnp_can_disable(pnp_dev) && pnp_can_write(pnp_dev)) {
187		error = pnp_stop_dev(pnp_dev);
188		if (error)
189			return error;
190	}
191
192	if (pnp_can_suspend(pnp_dev))
193		pnp_dev->protocol->suspend(pnp_dev, state);
194	return 0;
195}
196
197static int pnp_bus_suspend(struct device *dev)
198{
199	return __pnp_bus_suspend(dev, PMSG_SUSPEND);
200}
201
202static int pnp_bus_freeze(struct device *dev)
203{
204	return __pnp_bus_suspend(dev, PMSG_FREEZE);
205}
206
207static int pnp_bus_poweroff(struct device *dev)
208{
209	return __pnp_bus_suspend(dev, PMSG_HIBERNATE);
210}
211
212static int pnp_bus_resume(struct device *dev)
213{
214	struct pnp_dev *pnp_dev = to_pnp_dev(dev);
215	struct pnp_driver *pnp_drv = pnp_dev->driver;
216	int error;
217
218	if (!pnp_drv)
219		return 0;
220
221	if (pnp_dev->protocol->resume) {
222		error = pnp_dev->protocol->resume(pnp_dev);
223		if (error)
224			return error;
225	}
226
227	if (pnp_can_write(pnp_dev)) {
228		error = pnp_start_dev(pnp_dev);
229		if (error)
230			return error;
231	}
232
233	if (pnp_drv->driver.pm && pnp_drv->driver.pm->resume) {
234		error = pnp_drv->driver.pm->resume(dev);
235		if (error)
236			return error;
237	}
238
239	if (pnp_drv->resume) {
240		error = pnp_drv->resume(pnp_dev);
241		if (error)
242			return error;
243	}
244
245	return 0;
246}
247
248static const struct dev_pm_ops pnp_bus_dev_pm_ops = {
249	/* Suspend callbacks */
250	.suspend = pnp_bus_suspend,
251	.resume = pnp_bus_resume,
252	/* Hibernate callbacks */
253	.freeze = pnp_bus_freeze,
254	.thaw = pnp_bus_resume,
255	.poweroff = pnp_bus_poweroff,
256	.restore = pnp_bus_resume,
257};
258
259const struct bus_type pnp_bus_type = {
260	.name    = "pnp",
261	.match   = pnp_bus_match,
262	.probe   = pnp_device_probe,
263	.remove  = pnp_device_remove,
264	.shutdown = pnp_device_shutdown,
265	.pm	 = &pnp_bus_dev_pm_ops,
266	.dev_groups = pnp_dev_groups,
267};
268
269int pnp_register_driver(struct pnp_driver *drv)
270{
271	drv->driver.name = drv->name;
272	drv->driver.bus = &pnp_bus_type;
273
274	return driver_register(&drv->driver);
275}
276EXPORT_SYMBOL(pnp_register_driver);
277
278void pnp_unregister_driver(struct pnp_driver *drv)
279{
280	driver_unregister(&drv->driver);
281}
282EXPORT_SYMBOL(pnp_unregister_driver);
283
284/**
285 * pnp_add_id - adds an EISA id to the specified device
286 * @dev: pointer to the desired device
287 * @id: pointer to an EISA id string
288 */
289struct pnp_id *pnp_add_id(struct pnp_dev *dev, const char *id)
290{
291	struct pnp_id *dev_id, *ptr;
292
293	dev_id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
294	if (!dev_id)
295		return NULL;
296
297	dev_id->id[0] = id[0];
298	dev_id->id[1] = id[1];
299	dev_id->id[2] = id[2];
300	dev_id->id[3] = tolower(id[3]);
301	dev_id->id[4] = tolower(id[4]);
302	dev_id->id[5] = tolower(id[5]);
303	dev_id->id[6] = tolower(id[6]);
304	dev_id->id[7] = '\0';
305
306	dev_id->next = NULL;
307	ptr = dev->id;
308	while (ptr && ptr->next)
309		ptr = ptr->next;
310	if (ptr)
311		ptr->next = dev_id;
312	else
313		dev->id = dev_id;
314
315	return dev_id;
316}
317