drivers/pnp/card.c

   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 = pnp_alloc(sizeof(*clink));
  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 pnp_show_card_name(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(name, S_IRUGO, pnp_show_card_name, NULL);
 195
 196 static ssize_t pnp_show_card_ids(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(card_id, S_IRUGO, pnp_show_card_ids, NULL);
 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_remove_card - removes a PnP card from the PnP Layer
 274  * @card: pointer to the card to remove
 275  */
 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  */
 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  */
 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  */
 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
 373 /**
 374  * pnp_release_card_device - call this when the driver no longer needs the device
 375  * @dev: pointer to the PnP device structure
 376  */
 377 void pnp_release_card_device(struct pnp_dev *dev)
 378 {
 379         struct pnp_card_driver *drv = dev->card_link->driver;
 380
 381         drv->link.remove = &card_remove;
 382         device_release_driver(&dev->dev);
 383         drv->link.remove = &card_remove_first;
 384 }
 385
 386 /*
 387  * suspend/resume callbacks
 388  */
 389 static int card_suspend(struct pnp_dev *dev, pm_message_t state)
 390 {
 391         struct pnp_card_link *link = dev->card_link;
 392
 393         if (link->pm_state.event == state.event)
 394                 return 0;
 395         link->pm_state = state;
 396         return link->driver->suspend(link, state);
 397 }
 398
 399 static int card_resume(struct pnp_dev *dev)
 400 {
 401         struct pnp_card_link *link = dev->card_link;
 402
 403         if (link->pm_state.event == PM_EVENT_ON)
 404                 return 0;
 405         link->pm_state = PMSG_ON;
 406         link->driver->resume(link);
 407         return 0;
 408 }
 409
 410 /**
 411  * pnp_register_card_driver - registers a PnP card driver with the PnP Layer
 412  * @drv: pointer to the driver to register
 413  */
 414 int pnp_register_card_driver(struct pnp_card_driver *drv)
 415 {
 416         int error;
 417         struct list_head *pos, *temp;
 418
 419         drv->link.name = drv->name;
 420         drv->link.id_table = NULL;      /* this will disable auto matching */
 421         drv->link.flags = drv->flags;
 422         drv->link.probe = NULL;
 423         drv->link.remove = &card_remove_first;
 424         drv->link.suspend = drv->suspend ? card_suspend : NULL;
 425         drv->link.resume = drv->resume ? card_resume : NULL;
 426
 427         error = pnp_register_driver(&drv->link);
 428         if (error < 0)
 429                 return error;
 430
 431         mutex_lock(&pnp_lock);
 432         list_add_tail(&drv->global_list, &pnp_card_drivers);
 433         mutex_unlock(&pnp_lock);
 434
 435         list_for_each_safe(pos, temp, &pnp_cards) {
 436                 struct pnp_card *card =
 437                     list_entry(pos, struct pnp_card, global_list);
 438                 card_probe(card, drv);
 439         }
 440         return 0;
 441 }
 442
 443 /**
 444  * pnp_unregister_card_driver - unregisters a PnP card driver from the PnP Layer
 445  * @drv: pointer to the driver to unregister
 446  */
 447 void pnp_unregister_card_driver(struct pnp_card_driver *drv)
 448 {
 449         mutex_lock(&pnp_lock);
 450         list_del(&drv->global_list);
 451         mutex_unlock(&pnp_lock);
 452         pnp_unregister_driver(&drv->link);
 453 }
 454
 455 EXPORT_SYMBOL(pnp_request_card_device);
 456 EXPORT_SYMBOL(pnp_release_card_device);
 457 EXPORT_SYMBOL(pnp_register_card_driver);
 458 EXPORT_SYMBOL(pnp_unregister_card_driver);