1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * card.c - contains functions for managing groups of PnP devices
4  *
5  * Copyright 2002 Adam Belay <ambx1@neo.rr.com>
6  */
7 
8 #include <linux/module.h>
9 #include <linux/mutex.h>
10 #include <linux/ctype.h>
11 #include <linux/slab.h>
12 #include <linux/pnp.h>
13 #include <linux/dma-mapping.h>
14 #include "base.h"
15 
16 LIST_HEAD(pnp_cards);
17 static LIST_HEAD(pnp_card_drivers);
18 
match_card(struct pnp_card_driver * drv,struct pnp_card * card)19 static const struct pnp_card_device_id *match_card(struct pnp_card_driver *drv,
20 						   struct pnp_card *card)
21 {
22 	const struct pnp_card_device_id *drv_id = drv->id_table;
23 
24 	while (*drv_id->id) {
25 		if (compare_pnp_id(card->id, drv_id->id)) {
26 			int i = 0;
27 
28 			for (;;) {
29 				int found;
30 				struct pnp_dev *dev;
31 
32 				if (i == PNP_MAX_DEVICES ||
33 				    !*drv_id->devs[i].id)
34 					return drv_id;
35 				found = 0;
36 				card_for_each_dev(card, dev) {
37 					if (compare_pnp_id(dev->id,
38 						   drv_id->devs[i].id)) {
39 						found = 1;
40 						break;
41 					}
42 				}
43 				if (!found)
44 					break;
45 				i++;
46 			}
47 		}
48 		drv_id++;
49 	}
50 	return NULL;
51 }
52 
card_remove(struct pnp_dev * dev)53 static void card_remove(struct pnp_dev *dev)
54 {
55 	dev->card_link = NULL;
56 }
57 
card_remove_first(struct pnp_dev * dev)58 static void card_remove_first(struct pnp_dev *dev)
59 {
60 	struct pnp_card_driver *drv = to_pnp_card_driver(dev->driver);
61 
62 	if (!dev->card || !drv)
63 		return;
64 	if (drv->remove)
65 		drv->remove(dev->card_link);
66 	drv->link.remove = &card_remove;
67 	kfree(dev->card_link);
68 	card_remove(dev);
69 }
70 
card_probe(struct pnp_card * card,struct pnp_card_driver * drv)71 static int card_probe(struct pnp_card *card, struct pnp_card_driver *drv)
72 {
73 	const struct pnp_card_device_id *id;
74 	struct pnp_card_link *clink;
75 	struct pnp_dev *dev;
76 
77 	if (!drv->probe)
78 		return 0;
79 	id = match_card(drv, card);
80 	if (!id)
81 		return 0;
82 
83 	clink = kzalloc(sizeof(*clink), GFP_KERNEL);
84 	if (!clink)
85 		return 0;
86 	clink->card = card;
87 	clink->driver = drv;
88 	clink->pm_state = PMSG_ON;
89 
90 	if (drv->probe(clink, id) >= 0)
91 		return 1;
92 
93 	/* Recovery */
94 	card_for_each_dev(card, dev) {
95 		if (dev->card_link == clink)
96 			pnp_release_card_device(dev);
97 	}
98 	kfree(clink);
99 	return 0;
100 }
101 
102 /**
103  * pnp_add_card_id - adds an EISA id to the specified card
104  * @id: pointer to a pnp_id structure
105  * @card: pointer to the desired card
106  */
pnp_add_card_id(struct pnp_card * card,char * id)107 static struct pnp_id *pnp_add_card_id(struct pnp_card *card, char *id)
108 {
109 	struct pnp_id *dev_id, *ptr;
110 
111 	dev_id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
112 	if (!dev_id)
113 		return NULL;
114 
115 	dev_id->id[0] = id[0];
116 	dev_id->id[1] = id[1];
117 	dev_id->id[2] = id[2];
118 	dev_id->id[3] = tolower(id[3]);
119 	dev_id->id[4] = tolower(id[4]);
120 	dev_id->id[5] = tolower(id[5]);
121 	dev_id->id[6] = tolower(id[6]);
122 	dev_id->id[7] = '\0';
123 
124 	dev_id->next = NULL;
125 	ptr = card->id;
126 	while (ptr && ptr->next)
127 		ptr = ptr->next;
128 	if (ptr)
129 		ptr->next = dev_id;
130 	else
131 		card->id = dev_id;
132 
133 	return dev_id;
134 }
135 
pnp_free_card_ids(struct pnp_card * card)136 static void pnp_free_card_ids(struct pnp_card *card)
137 {
138 	struct pnp_id *id;
139 	struct pnp_id *next;
140 
141 	id = card->id;
142 	while (id) {
143 		next = id->next;
144 		kfree(id);
145 		id = next;
146 	}
147 }
148 
pnp_release_card(struct device * dmdev)149 static void pnp_release_card(struct device *dmdev)
150 {
151 	struct pnp_card *card = to_pnp_card(dmdev);
152 
153 	pnp_free_card_ids(card);
154 	kfree(card);
155 }
156 
pnp_alloc_card(struct pnp_protocol * protocol,int id,char * pnpid)157 struct pnp_card *pnp_alloc_card(struct pnp_protocol *protocol, int id, char *pnpid)
158 {
159 	struct pnp_card *card;
160 	struct pnp_id *dev_id;
161 
162 	card = kzalloc(sizeof(struct pnp_card), GFP_KERNEL);
163 	if (!card)
164 		return NULL;
165 
166 	card->protocol = protocol;
167 	card->number = id;
168 
169 	card->dev.parent = &card->protocol->dev;
170 	dev_set_name(&card->dev, "%02x:%02x", card->protocol->number, card->number);
171 
172 	card->dev.coherent_dma_mask = DMA_BIT_MASK(24);
173 	card->dev.dma_mask = &card->dev.coherent_dma_mask;
174 
175 	dev_id = pnp_add_card_id(card, pnpid);
176 	if (!dev_id) {
177 		kfree(card);
178 		return NULL;
179 	}
180 
181 	return card;
182 }
183 
name_show(struct device * dmdev,struct device_attribute * attr,char * buf)184 static ssize_t name_show(struct device *dmdev,
185 			 struct device_attribute *attr, char *buf)
186 {
187 	char *str = buf;
188 	struct pnp_card *card = to_pnp_card(dmdev);
189 
190 	str += sprintf(str, "%s\n", card->name);
191 	return (str - buf);
192 }
193 
194 static DEVICE_ATTR_RO(name);
195 
card_id_show(struct device * dmdev,struct device_attribute * attr,char * buf)196 static ssize_t card_id_show(struct device *dmdev,
197 			    struct device_attribute *attr, char *buf)
198 {
199 	char *str = buf;
200 	struct pnp_card *card = to_pnp_card(dmdev);
201 	struct pnp_id *pos = card->id;
202 
203 	while (pos) {
204 		str += sprintf(str, "%s\n", pos->id);
205 		pos = pos->next;
206 	}
207 	return (str - buf);
208 }
209 
210 static DEVICE_ATTR_RO(card_id);
211 
pnp_interface_attach_card(struct pnp_card * card)212 static int pnp_interface_attach_card(struct pnp_card *card)
213 {
214 	int rc = device_create_file(&card->dev, &dev_attr_name);
215 
216 	if (rc)
217 		return rc;
218 
219 	rc = device_create_file(&card->dev, &dev_attr_card_id);
220 	if (rc)
221 		goto err_name;
222 
223 	return 0;
224 
225 err_name:
226 	device_remove_file(&card->dev, &dev_attr_name);
227 	return rc;
228 }
229 
230 /**
231  * pnp_add_card - adds a PnP card to the PnP Layer
232  * @card: pointer to the card to add
233  */
pnp_add_card(struct pnp_card * card)234 int pnp_add_card(struct pnp_card *card)
235 {
236 	int error;
237 	struct list_head *pos, *temp;
238 
239 	card->dev.bus = NULL;
240 	card->dev.release = &pnp_release_card;
241 	error = device_register(&card->dev);
242 	if (error) {
243 		dev_err(&card->dev, "could not register (err=%d)\n", error);
244 		put_device(&card->dev);
245 		return error;
246 	}
247 
248 	pnp_interface_attach_card(card);
249 	mutex_lock(&pnp_lock);
250 	list_add_tail(&card->global_list, &pnp_cards);
251 	list_add_tail(&card->protocol_list, &card->protocol->cards);
252 	mutex_unlock(&pnp_lock);
253 
254 	/* we wait until now to add devices in order to ensure the drivers
255 	 * will be able to use all of the related devices on the card
256 	 * without waiting an unreasonable length of time */
257 	list_for_each(pos, &card->devices) {
258 		struct pnp_dev *dev = card_to_pnp_dev(pos);
259 		__pnp_add_device(dev);
260 	}
261 
262 	/* match with card drivers */
263 	list_for_each_safe(pos, temp, &pnp_card_drivers) {
264 		struct pnp_card_driver *drv =
265 		    list_entry(pos, struct pnp_card_driver,
266 			       global_list);
267 		card_probe(card, drv);
268 	}
269 	return 0;
270 }
271 
272 /**
273  * pnp_remove_card - removes a PnP card from the PnP Layer
274  * @card: pointer to the card to remove
275  */
pnp_remove_card(struct pnp_card * card)276 void pnp_remove_card(struct pnp_card *card)
277 {
278 	struct list_head *pos, *temp;
279 
280 	device_unregister(&card->dev);
281 	mutex_lock(&pnp_lock);
282 	list_del(&card->global_list);
283 	list_del(&card->protocol_list);
284 	mutex_unlock(&pnp_lock);
285 	list_for_each_safe(pos, temp, &card->devices) {
286 		struct pnp_dev *dev = card_to_pnp_dev(pos);
287 		pnp_remove_card_device(dev);
288 	}
289 }
290 
291 /**
292  * pnp_add_card_device - adds a device to the specified card
293  * @card: pointer to the card to add to
294  * @dev: pointer to the device to add
295  */
pnp_add_card_device(struct pnp_card * card,struct pnp_dev * dev)296 int pnp_add_card_device(struct pnp_card *card, struct pnp_dev *dev)
297 {
298 	dev->dev.parent = &card->dev;
299 	dev->card_link = NULL;
300 	dev_set_name(&dev->dev, "%02x:%02x.%02x",
301 		     dev->protocol->number, card->number, dev->number);
302 	mutex_lock(&pnp_lock);
303 	dev->card = card;
304 	list_add_tail(&dev->card_list, &card->devices);
305 	mutex_unlock(&pnp_lock);
306 	return 0;
307 }
308 
309 /**
310  * pnp_remove_card_device- removes a device from the specified card
311  * @dev: pointer to the device to remove
312  */
pnp_remove_card_device(struct pnp_dev * dev)313 void pnp_remove_card_device(struct pnp_dev *dev)
314 {
315 	mutex_lock(&pnp_lock);
316 	dev->card = NULL;
317 	list_del(&dev->card_list);
318 	mutex_unlock(&pnp_lock);
319 	__pnp_remove_device(dev);
320 }
321 
322 /**
323  * pnp_request_card_device - Searches for a PnP device under the specified card
324  * @clink: pointer to the card link, cannot be NULL
325  * @id: pointer to a PnP ID structure that explains the rules for finding the device
326  * @from: Starting place to search from. If NULL it will start from the beginning.
327  */
pnp_request_card_device(struct pnp_card_link * clink,const char * id,struct pnp_dev * from)328 struct pnp_dev *pnp_request_card_device(struct pnp_card_link *clink,
329 					const char *id, struct pnp_dev *from)
330 {
331 	struct list_head *pos;
332 	struct pnp_dev *dev;
333 	struct pnp_card_driver *drv;
334 	struct pnp_card *card;
335 
336 	if (!clink || !id)
337 		return NULL;
338 
339 	card = clink->card;
340 	drv = clink->driver;
341 	if (!from) {
342 		pos = card->devices.next;
343 	} else {
344 		if (from->card != card)
345 			return NULL;
346 		pos = from->card_list.next;
347 	}
348 	while (pos != &card->devices) {
349 		dev = card_to_pnp_dev(pos);
350 		if ((!dev->card_link) && compare_pnp_id(dev->id, id))
351 			goto found;
352 		pos = pos->next;
353 	}
354 
355 	return NULL;
356 
357 found:
358 	dev->card_link = clink;
359 	dev->dev.driver = &drv->link.driver;
360 	if (pnp_bus_type.probe(&dev->dev))
361 		goto err_out;
362 	if (device_bind_driver(&dev->dev))
363 		goto err_out;
364 
365 	return dev;
366 
367 err_out:
368 	dev->dev.driver = NULL;
369 	dev->card_link = NULL;
370 	return NULL;
371 }
372 EXPORT_SYMBOL(pnp_request_card_device);
373 
374 /**
375  * pnp_release_card_device - call this when the driver no longer needs the device
376  * @dev: pointer to the PnP device structure
377  */
pnp_release_card_device(struct pnp_dev * dev)378 void pnp_release_card_device(struct pnp_dev *dev)
379 {
380 	struct pnp_card_driver *drv = dev->card_link->driver;
381 
382 	drv->link.remove = &card_remove;
383 	device_release_driver(&dev->dev);
384 	drv->link.remove = &card_remove_first;
385 }
386 EXPORT_SYMBOL(pnp_release_card_device);
387 
388 /*
389  * suspend/resume callbacks
390  */
card_suspend(struct pnp_dev * dev,pm_message_t state)391 static int card_suspend(struct pnp_dev *dev, pm_message_t state)
392 {
393 	struct pnp_card_link *link = dev->card_link;
394 
395 	if (link->pm_state.event == state.event)
396 		return 0;
397 	link->pm_state = state;
398 	return link->driver->suspend(link, state);
399 }
400 
card_resume(struct pnp_dev * dev)401 static int card_resume(struct pnp_dev *dev)
402 {
403 	struct pnp_card_link *link = dev->card_link;
404 
405 	if (link->pm_state.event == PM_EVENT_ON)
406 		return 0;
407 	link->pm_state = PMSG_ON;
408 	link->driver->resume(link);
409 	return 0;
410 }
411 
412 /**
413  * pnp_register_card_driver - registers a PnP card driver with the PnP Layer
414  * @drv: pointer to the driver to register
415  */
pnp_register_card_driver(struct pnp_card_driver * drv)416 int pnp_register_card_driver(struct pnp_card_driver *drv)
417 {
418 	int error;
419 	struct list_head *pos, *temp;
420 
421 	drv->link.name = drv->name;
422 	drv->link.id_table = NULL;	/* this will disable auto matching */
423 	drv->link.flags = drv->flags;
424 	drv->link.probe = NULL;
425 	drv->link.remove = &card_remove_first;
426 	drv->link.suspend = drv->suspend ? card_suspend : NULL;
427 	drv->link.resume = drv->resume ? card_resume : NULL;
428 
429 	error = pnp_register_driver(&drv->link);
430 	if (error < 0)
431 		return error;
432 
433 	mutex_lock(&pnp_lock);
434 	list_add_tail(&drv->global_list, &pnp_card_drivers);
435 	mutex_unlock(&pnp_lock);
436 
437 	list_for_each_safe(pos, temp, &pnp_cards) {
438 		struct pnp_card *card =
439 		    list_entry(pos, struct pnp_card, global_list);
440 		card_probe(card, drv);
441 	}
442 	return 0;
443 }
444 EXPORT_SYMBOL(pnp_register_card_driver);
445 
446 /**
447  * pnp_unregister_card_driver - unregisters a PnP card driver from the PnP Layer
448  * @drv: pointer to the driver to unregister
449  */
pnp_unregister_card_driver(struct pnp_card_driver * drv)450 void pnp_unregister_card_driver(struct pnp_card_driver *drv)
451 {
452 	mutex_lock(&pnp_lock);
453 	list_del(&drv->global_list);
454 	mutex_unlock(&pnp_lock);
455 	pnp_unregister_driver(&drv->link);
456 }
457 EXPORT_SYMBOL(pnp_unregister_card_driver);
458