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 
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 
53 static void card_remove(struct pnp_dev *dev)
54 {
55 	dev->card_link = NULL;
56 }
57 
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 
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  */
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 
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 
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 
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 
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 
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 
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  */
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_add_card_device - adds a device to the specified card
274  * @card: pointer to the card to add to
275  * @dev: pointer to the device to add
276  */
277 int pnp_add_card_device(struct pnp_card *card, struct pnp_dev *dev)
278 {
279 	dev->dev.parent = &card->dev;
280 	dev->card_link = NULL;
281 	dev_set_name(&dev->dev, "%02x:%02x.%02x",
282 		     dev->protocol->number, card->number, dev->number);
283 	mutex_lock(&pnp_lock);
284 	dev->card = card;
285 	list_add_tail(&dev->card_list, &card->devices);
286 	mutex_unlock(&pnp_lock);
287 	return 0;
288 }
289 
290 /**
291  * pnp_request_card_device - Searches for a PnP device under the specified card
292  * @clink: pointer to the card link, cannot be NULL
293  * @id: pointer to a PnP ID structure that explains the rules for finding the device
294  * @from: Starting place to search from. If NULL it will start from the beginning.
295  */
296 struct pnp_dev *pnp_request_card_device(struct pnp_card_link *clink,
297 					const char *id, struct pnp_dev *from)
298 {
299 	struct list_head *pos;
300 	struct pnp_dev *dev;
301 	struct pnp_card_driver *drv;
302 	struct pnp_card *card;
303 
304 	if (!clink || !id)
305 		return NULL;
306 
307 	card = clink->card;
308 	drv = clink->driver;
309 	if (!from) {
310 		pos = card->devices.next;
311 	} else {
312 		if (from->card != card)
313 			return NULL;
314 		pos = from->card_list.next;
315 	}
316 	while (pos != &card->devices) {
317 		dev = card_to_pnp_dev(pos);
318 		if ((!dev->card_link) && compare_pnp_id(dev->id, id))
319 			goto found;
320 		pos = pos->next;
321 	}
322 
323 	return NULL;
324 
325 found:
326 	dev->card_link = clink;
327 	dev->dev.driver = &drv->link.driver;
328 	if (pnp_bus_type.probe(&dev->dev))
329 		goto err_out;
330 	if (device_bind_driver(&dev->dev))
331 		goto err_out;
332 
333 	return dev;
334 
335 err_out:
336 	dev->dev.driver = NULL;
337 	dev->card_link = NULL;
338 	return NULL;
339 }
340 EXPORT_SYMBOL(pnp_request_card_device);
341 
342 /**
343  * pnp_release_card_device - call this when the driver no longer needs the device
344  * @dev: pointer to the PnP device structure
345  */
346 void pnp_release_card_device(struct pnp_dev *dev)
347 {
348 	struct pnp_card_driver *drv = dev->card_link->driver;
349 
350 	drv->link.remove = &card_remove;
351 	device_release_driver(&dev->dev);
352 	drv->link.remove = &card_remove_first;
353 }
354 EXPORT_SYMBOL(pnp_release_card_device);
355 
356 /*
357  * suspend/resume callbacks
358  */
359 static int card_suspend(struct pnp_dev *dev, pm_message_t state)
360 {
361 	struct pnp_card_link *link = dev->card_link;
362 
363 	if (link->pm_state.event == state.event)
364 		return 0;
365 	link->pm_state = state;
366 	return link->driver->suspend(link, state);
367 }
368 
369 static int card_resume(struct pnp_dev *dev)
370 {
371 	struct pnp_card_link *link = dev->card_link;
372 
373 	if (link->pm_state.event == PM_EVENT_ON)
374 		return 0;
375 	link->pm_state = PMSG_ON;
376 	link->driver->resume(link);
377 	return 0;
378 }
379 
380 /**
381  * pnp_register_card_driver - registers a PnP card driver with the PnP Layer
382  * @drv: pointer to the driver to register
383  */
384 int pnp_register_card_driver(struct pnp_card_driver *drv)
385 {
386 	int error;
387 	struct list_head *pos, *temp;
388 
389 	drv->link.name = drv->name;
390 	drv->link.id_table = NULL;	/* this will disable auto matching */
391 	drv->link.flags = drv->flags;
392 	drv->link.probe = NULL;
393 	drv->link.remove = &card_remove_first;
394 	drv->link.suspend = drv->suspend ? card_suspend : NULL;
395 	drv->link.resume = drv->resume ? card_resume : NULL;
396 
397 	error = pnp_register_driver(&drv->link);
398 	if (error < 0)
399 		return error;
400 
401 	mutex_lock(&pnp_lock);
402 	list_add_tail(&drv->global_list, &pnp_card_drivers);
403 	mutex_unlock(&pnp_lock);
404 
405 	list_for_each_safe(pos, temp, &pnp_cards) {
406 		struct pnp_card *card =
407 		    list_entry(pos, struct pnp_card, global_list);
408 		card_probe(card, drv);
409 	}
410 	return 0;
411 }
412 EXPORT_SYMBOL(pnp_register_card_driver);
413 
414 /**
415  * pnp_unregister_card_driver - unregisters a PnP card driver from the PnP Layer
416  * @drv: pointer to the driver to unregister
417  */
418 void pnp_unregister_card_driver(struct pnp_card_driver *drv)
419 {
420 	mutex_lock(&pnp_lock);
421 	list_del(&drv->global_list);
422 	mutex_unlock(&pnp_lock);
423 	pnp_unregister_driver(&drv->link);
424 }
425 EXPORT_SYMBOL(pnp_unregister_card_driver);
426