drivers/memstick/core/memstick.c

   1 /*
   2  *  Sony MemoryStick support
   3  *
   4  *  Copyright (C) 2007 Alex Dubov <oakad@yahoo.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * Special thanks to Carlos Corbacho for providing various MemoryStick cards
  11  * that made this driver possible.
  12  *
  13  */
  14
  15 #include <linux/memstick.h>
  16 #include <linux/idr.h>
  17 #include <linux/fs.h>
  18 #include <linux/delay.h>
  19
  20 #define DRIVER_NAME "memstick"
  21
  22 static unsigned int cmd_retries = 3;
  23 module_param(cmd_retries, uint, 0644);
  24
  25 static struct workqueue_struct *workqueue;
  26 static DEFINE_IDR(memstick_host_idr);
  27 static DEFINE_SPINLOCK(memstick_host_lock);
  28
  29 static int memstick_dev_match(struct memstick_dev *card,
  30                               struct memstick_device_id *id)
  31 {
  32         if (id->match_flags & MEMSTICK_MATCH_ALL) {
  33                 if ((id->type == card->id.type)
  34                     && (id->category == card->id.category)
  35                     && (id->class == card->id.class))
  36                         return 1;
  37         }
  38
  39         return 0;
  40 }
  41
  42 static int memstick_bus_match(struct device *dev, struct device_driver *drv)
  43 {
  44         struct memstick_dev *card = container_of(dev, struct memstick_dev,
  45                                                  dev);
  46         struct memstick_driver *ms_drv = container_of(drv,
  47                                                       struct memstick_driver,
  48                                                       driver);
  49         struct memstick_device_id *ids = ms_drv->id_table;
  50
  51         if (ids) {
  52                 while (ids->match_flags) {
  53                         if (memstick_dev_match(card, ids))
  54                                 return 1;
  55                         ++ids;
  56                 }
  57         }
  58         return 0;
  59 }
  60
  61 static int memstick_uevent(struct device *dev, struct kobj_uevent_env *env)
  62 {
  63         struct memstick_dev *card = container_of(dev, struct memstick_dev,
  64                                                   dev);
  65
  66         if (add_uevent_var(env, "MEMSTICK_TYPE=%02X", card->id.type))
  67                 return -ENOMEM;
  68
  69         if (add_uevent_var(env, "MEMSTICK_CATEGORY=%02X", card->id.category))
  70                 return -ENOMEM;
  71
  72         if (add_uevent_var(env, "MEMSTICK_CLASS=%02X", card->id.class))
  73                 return -ENOMEM;
  74
  75         return 0;
  76 }
  77
  78 static int memstick_device_probe(struct device *dev)
  79 {
  80         struct memstick_dev *card = container_of(dev, struct memstick_dev,
  81                                                  dev);
  82         struct memstick_driver *drv = container_of(dev->driver,
  83                                                    struct memstick_driver,
  84                                                    driver);
  85         int rc = -ENODEV;
  86
  87         if (dev->driver && drv->probe) {
  88                 rc = drv->probe(card);
  89                 if (!rc)
  90                         get_device(dev);
  91         }
  92         return rc;
  93 }
  94
  95 static int memstick_device_remove(struct device *dev)
  96 {
  97         struct memstick_dev *card = container_of(dev, struct memstick_dev,
  98                                                   dev);
  99         struct memstick_driver *drv = container_of(dev->driver,
 100                                                    struct memstick_driver,
 101                                                    driver);
 102
 103         if (dev->driver && drv->remove) {
 104                 drv->remove(card);
 105                 card->dev.driver = NULL;
 106         }
 107
 108         put_device(dev);
 109         return 0;
 110 }
 111
 112 #ifdef CONFIG_PM
 113
 114 static int memstick_device_suspend(struct device *dev, pm_message_t state)
 115 {
 116         struct memstick_dev *card = container_of(dev, struct memstick_dev,
 117                                                   dev);
 118         struct memstick_driver *drv = container_of(dev->driver,
 119                                                    struct memstick_driver,
 120                                                    driver);
 121
 122         if (dev->driver && drv->suspend)
 123                 return drv->suspend(card, state);
 124         return 0;
 125 }
 126
 127 static int memstick_device_resume(struct device *dev)
 128 {
 129         struct memstick_dev *card = container_of(dev, struct memstick_dev,
 130                                                   dev);
 131         struct memstick_driver *drv = container_of(dev->driver,
 132                                                    struct memstick_driver,
 133                                                    driver);
 134
 135         if (dev->driver && drv->resume)
 136                 return drv->resume(card);
 137         return 0;
 138 }
 139
 140 #else
 141
 142 #define memstick_device_suspend NULL
 143 #define memstick_device_resume NULL
 144
 145 #endif /* CONFIG_PM */
 146
 147 #define MEMSTICK_ATTR(name, format)                                           \
 148 static ssize_t name##_show(struct device *dev, struct device_attribute *attr, \
 149                             char *buf)                                        \
 150 {                                                                             \
 151         struct memstick_dev *card = container_of(dev, struct memstick_dev,    \
 152                                                  dev);                        \
 153         return sprintf(buf, format, card->id.name);                           \
 154 }
 155
 156 MEMSTICK_ATTR(type, "%02X");
 157 MEMSTICK_ATTR(category, "%02X");
 158 MEMSTICK_ATTR(class, "%02X");
 159
 160 #define MEMSTICK_ATTR_RO(name) __ATTR(name, S_IRUGO, name##_show, NULL)
 161
 162 static struct device_attribute memstick_dev_attrs[] = {
 163         MEMSTICK_ATTR_RO(type),
 164         MEMSTICK_ATTR_RO(category),
 165         MEMSTICK_ATTR_RO(class),
 166         __ATTR_NULL
 167 };
 168
 169 static struct bus_type memstick_bus_type = {
 170         .name           = "memstick",
 171         .dev_attrs      = memstick_dev_attrs,
 172         .match          = memstick_bus_match,
 173         .uevent         = memstick_uevent,
 174         .probe          = memstick_device_probe,
 175         .remove         = memstick_device_remove,
 176         .suspend        = memstick_device_suspend,
 177         .resume         = memstick_device_resume
 178 };
 179
 180 static void memstick_free(struct class_device *cdev)
 181 {
 182         struct memstick_host *host = container_of(cdev, struct memstick_host,
 183                                                   cdev);
 184         kfree(host);
 185 }
 186
 187 static struct class memstick_host_class = {
 188         .name       = "memstick_host",
 189         .release    = memstick_free
 190 };
 191
 192 static void memstick_free_card(struct device *dev)
 193 {
 194         struct memstick_dev *card = container_of(dev, struct memstick_dev,
 195                                                  dev);
 196         kfree(card);
 197 }
 198
 199 static int memstick_dummy_check(struct memstick_dev *card)
 200 {
 201         return 0;
 202 }
 203
 204 /**
 205  * memstick_detect_change - schedule media detection on memstick host
 206  * @host - host to use
 207  */
 208 void memstick_detect_change(struct memstick_host *host)
 209 {
 210         queue_work(workqueue, &host->media_checker);
 211 }
 212 EXPORT_SYMBOL(memstick_detect_change);
 213
 214 /**
 215  * memstick_next_req - called by host driver to obtain next request to process
 216  * @host - host to use
 217  * @mrq - pointer to stick the request to
 218  *
 219  * Host calls this function from idle state (*mrq == NULL) or after finishing
 220  * previous request (*mrq should point to it). If previous request was
 221  * unsuccessful, it is retried for predetermined number of times. Return value
 222  * of 0 means that new request was assigned to the host.
 223  */
 224 int memstick_next_req(struct memstick_host *host, struct memstick_request **mrq)
 225 {
 226         int rc = -ENXIO;
 227
 228         if ((*mrq) && (*mrq)->error && host->retries) {
 229                 (*mrq)->error = rc;
 230                 host->retries--;
 231                 return 0;
 232         }
 233
 234         if (host->card && host->card->next_request)
 235                 rc = host->card->next_request(host->card, mrq);
 236
 237         if (!rc)
 238                 host->retries = cmd_retries > 1 ? cmd_retries - 1 : 1;
 239         else
 240                 *mrq = NULL;
 241
 242         return rc;
 243 }
 244 EXPORT_SYMBOL(memstick_next_req);
 245
 246 /**
 247  * memstick_new_req - notify the host that some requests are pending
 248  * @host - host to use
 249  */
 250 void memstick_new_req(struct memstick_host *host)
 251 {
 252         host->retries = cmd_retries;
 253         host->request(host);
 254 }
 255 EXPORT_SYMBOL(memstick_new_req);
 256
 257 /**
 258  * memstick_init_req_sg - set request fields needed for bulk data transfer
 259  * @mrq - request to use
 260  * @tpc - memstick Transport Protocol Command
 261  * @sg - TPC argument
 262  */
 263 void memstick_init_req_sg(struct memstick_request *mrq, unsigned char tpc,
 264                           struct scatterlist *sg)
 265 {
 266         mrq->tpc = tpc;
 267         if (tpc & 8)
 268                 mrq->data_dir = WRITE;
 269         else
 270                 mrq->data_dir = READ;
 271
 272         mrq->sg = *sg;
 273         mrq->long_data = 1;
 274
 275         if (tpc == MS_TPC_SET_CMD || tpc == MS_TPC_EX_SET_CMD)
 276                 mrq->need_card_int = 1;
 277         else
 278                 mrq->need_card_int = 0;
 279
 280         mrq->get_int_reg = 0;
 281 }
 282 EXPORT_SYMBOL(memstick_init_req_sg);
 283
 284 /**
 285  * memstick_init_req - set request fields needed for short data transfer
 286  * @mrq - request to use
 287  * @tpc - memstick Transport Protocol Command
 288  * @buf - TPC argument buffer
 289  * @length - TPC argument size
 290  *
 291  * The intended use of this function (transfer of data items several bytes
 292  * in size) allows us to just copy the value between request structure and
 293  * user supplied buffer.
 294  */
 295 void memstick_init_req(struct memstick_request *mrq, unsigned char tpc,
 296                        void *buf, size_t length)
 297 {
 298         mrq->tpc = tpc;
 299         if (tpc & 8)
 300                 mrq->data_dir = WRITE;
 301         else
 302                 mrq->data_dir = READ;
 303
 304         mrq->data_len = length > sizeof(mrq->data) ? sizeof(mrq->data) : length;
 305         if (mrq->data_dir == WRITE)
 306                 memcpy(mrq->data, buf, mrq->data_len);
 307
 308         mrq->long_data = 0;
 309
 310         if (tpc == MS_TPC_SET_CMD || tpc == MS_TPC_EX_SET_CMD)
 311                 mrq->need_card_int = 1;
 312         else
 313                 mrq->need_card_int = 0;
 314
 315         mrq->get_int_reg = 0;
 316 }
 317 EXPORT_SYMBOL(memstick_init_req);
 318
 319 /*
 320  * Functions prefixed with "h_" are protocol callbacks. They can be called from
 321  * interrupt context. Return value of 0 means that request processing is still
 322  * ongoing, while special error value of -EAGAIN means that current request is
 323  * finished (and request processor should come back some time later).
 324  */
 325
 326 static int h_memstick_read_dev_id(struct memstick_dev *card,
 327                                   struct memstick_request **mrq)
 328 {
 329         struct ms_id_register id_reg;
 330
 331         if (!(*mrq)) {
 332                 memstick_init_req(&card->current_mrq, MS_TPC_READ_REG, NULL,
 333                                   sizeof(struct ms_id_register));
 334                 *mrq = &card->current_mrq;
 335                 return 0;
 336         } else {
 337                 if (!(*mrq)->error) {
 338                         memcpy(&id_reg, (*mrq)->data, sizeof(id_reg));
 339                         card->id.match_flags = MEMSTICK_MATCH_ALL;
 340                         card->id.type = id_reg.type;
 341                         card->id.category = id_reg.category;
 342                         card->id.class = id_reg.class;
 343                 }
 344                 complete(&card->mrq_complete);
 345                 return -EAGAIN;
 346         }
 347 }
 348
 349 static int h_memstick_set_rw_addr(struct memstick_dev *card,
 350                                   struct memstick_request **mrq)
 351 {
 352         if (!(*mrq)) {
 353                 memstick_init_req(&card->current_mrq, MS_TPC_SET_RW_REG_ADRS,
 354                                   (char *)&card->reg_addr,
 355                                   sizeof(card->reg_addr));
 356                 *mrq = &card->current_mrq;
 357                 return 0;
 358         } else {
 359                 complete(&card->mrq_complete);
 360                 return -EAGAIN;
 361         }
 362 }
 363
 364 /**
 365  * memstick_set_rw_addr - issue SET_RW_REG_ADDR request and wait for it to
 366  *                        complete
 367  * @card - media device to use
 368  */
 369 int memstick_set_rw_addr(struct memstick_dev *card)
 370 {
 371         card->next_request = h_memstick_set_rw_addr;
 372         memstick_new_req(card->host);
 373         wait_for_completion(&card->mrq_complete);
 374
 375         return card->current_mrq.error;
 376 }
 377 EXPORT_SYMBOL(memstick_set_rw_addr);
 378
 379 static struct memstick_dev *memstick_alloc_card(struct memstick_host *host)
 380 {
 381         struct memstick_dev *card = kzalloc(sizeof(struct memstick_dev),
 382                                             GFP_KERNEL);
 383         struct memstick_dev *old_card = host->card;
 384         struct ms_id_register id_reg;
 385
 386         if (card) {
 387                 card->host = host;
 388                 snprintf(card->dev.bus_id, sizeof(card->dev.bus_id),
 389                          "%s", host->cdev.class_id);
 390                 card->dev.parent = host->cdev.dev;
 391                 card->dev.bus = &memstick_bus_type;
 392                 card->dev.release = memstick_free_card;
 393                 card->check = memstick_dummy_check;
 394
 395                 card->reg_addr.r_offset = offsetof(struct ms_register, id);
 396                 card->reg_addr.r_length = sizeof(id_reg);
 397                 card->reg_addr.w_offset = offsetof(struct ms_register, id);
 398                 card->reg_addr.w_length = sizeof(id_reg);
 399
 400                 init_completion(&card->mrq_complete);
 401
 402                 host->card = card;
 403                 if (memstick_set_rw_addr(card))
 404                         goto err_out;
 405
 406                 card->next_request = h_memstick_read_dev_id;
 407                 memstick_new_req(host);
 408                 wait_for_completion(&card->mrq_complete);
 409
 410                 if (card->current_mrq.error)
 411                         goto err_out;
 412         }
 413         host->card = old_card;
 414         return card;
 415 err_out:
 416         host->card = old_card;
 417         kfree(card);
 418         return NULL;
 419 }
 420
 421 static void memstick_power_on(struct memstick_host *host)
 422 {
 423         host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_ON);
 424         host->set_param(host, MEMSTICK_INTERFACE, MEMSTICK_SERIAL);
 425         msleep(1);
 426 }
 427
 428 static void memstick_check(struct work_struct *work)
 429 {
 430         struct memstick_host *host = container_of(work, struct memstick_host,
 431                                                   media_checker);
 432         struct memstick_dev *card;
 433
 434         dev_dbg(host->cdev.dev, "memstick_check started\n");
 435         mutex_lock(&host->lock);
 436         if (!host->card)
 437                 memstick_power_on(host);
 438
 439         card = memstick_alloc_card(host);
 440
 441         if (!card) {
 442                 if (host->card) {
 443                         device_unregister(&host->card->dev);
 444                         host->card = NULL;
 445                 }
 446         } else {
 447                 dev_dbg(host->cdev.dev, "new card %02x, %02x, %02x\n",
 448                         card->id.type, card->id.category, card->id.class);
 449                 if (host->card) {
 450                         if (memstick_set_rw_addr(host->card)
 451                             || !memstick_dev_match(host->card, &card->id)
 452                             || !(host->card->check(host->card))) {
 453                                 device_unregister(&host->card->dev);
 454                                 host->card = NULL;
 455                         }
 456                 }
 457
 458                 if (!host->card) {
 459                         host->card = card;
 460                         if (device_register(&card->dev)) {
 461                                 kfree(host->card);
 462                                 host->card = NULL;
 463                         }
 464                 } else
 465                         kfree(card);
 466         }
 467
 468         if (!host->card)
 469                 host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
 470
 471         mutex_unlock(&host->lock);
 472         dev_dbg(host->cdev.dev, "memstick_check finished\n");
 473 }
 474
 475 /**
 476  * memstick_alloc_host - allocate a memstick_host structure
 477  * @extra: size of the user private data to allocate
 478  * @dev: parent device of the host
 479  */
 480 struct memstick_host *memstick_alloc_host(unsigned int extra,
 481                                           struct device *dev)
 482 {
 483         struct memstick_host *host;
 484
 485         host = kzalloc(sizeof(struct memstick_host) + extra, GFP_KERNEL);
 486         if (host) {
 487                 mutex_init(&host->lock);
 488                 INIT_WORK(&host->media_checker, memstick_check);
 489                 host->cdev.class = &memstick_host_class;
 490                 host->cdev.dev = dev;
 491                 class_device_initialize(&host->cdev);
 492         }
 493         return host;
 494 }
 495 EXPORT_SYMBOL(memstick_alloc_host);
 496
 497 /**
 498  * memstick_add_host - start request processing on memstick host
 499  * @host - host to use
 500  */
 501 int memstick_add_host(struct memstick_host *host)
 502 {
 503         int rc;
 504
 505         if (!idr_pre_get(&memstick_host_idr, GFP_KERNEL))
 506                 return -ENOMEM;
 507
 508         spin_lock(&memstick_host_lock);
 509         rc = idr_get_new(&memstick_host_idr, host, &host->id);
 510         spin_unlock(&memstick_host_lock);
 511         if (rc)
 512                 return rc;
 513
 514         snprintf(host->cdev.class_id, BUS_ID_SIZE,
 515                  "memstick%u", host->id);
 516
 517         rc = class_device_add(&host->cdev);
 518         if (rc) {
 519                 spin_lock(&memstick_host_lock);
 520                 idr_remove(&memstick_host_idr, host->id);
 521                 spin_unlock(&memstick_host_lock);
 522                 return rc;
 523         }
 524
 525         host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
 526         memstick_detect_change(host);
 527         return 0;
 528 }
 529 EXPORT_SYMBOL(memstick_add_host);
 530
 531 /**
 532  * memstick_remove_host - stop request processing on memstick host
 533  * @host - host to use
 534  */
 535 void memstick_remove_host(struct memstick_host *host)
 536 {
 537         flush_workqueue(workqueue);
 538         mutex_lock(&host->lock);
 539         if (host->card)
 540                 device_unregister(&host->card->dev);
 541         host->card = NULL;
 542         host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
 543         mutex_unlock(&host->lock);
 544
 545         spin_lock(&memstick_host_lock);
 546         idr_remove(&memstick_host_idr, host->id);
 547         spin_unlock(&memstick_host_lock);
 548         class_device_del(&host->cdev);
 549 }
 550 EXPORT_SYMBOL(memstick_remove_host);
 551
 552 /**
 553  * memstick_free_host - free memstick host
 554  * @host - host to use
 555  */
 556 void memstick_free_host(struct memstick_host *host)
 557 {
 558         mutex_destroy(&host->lock);
 559         class_device_put(&host->cdev);
 560 }
 561 EXPORT_SYMBOL(memstick_free_host);
 562
 563 /**
 564  * memstick_suspend_host - notify bus driver of host suspension
 565  * @host - host to use
 566  */
 567 void memstick_suspend_host(struct memstick_host *host)
 568 {
 569         mutex_lock(&host->lock);
 570         host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
 571         mutex_unlock(&host->lock);
 572 }
 573 EXPORT_SYMBOL(memstick_suspend_host);
 574
 575 /**
 576  * memstick_resume_host - notify bus driver of host resumption
 577  * @host - host to use
 578  */
 579 void memstick_resume_host(struct memstick_host *host)
 580 {
 581         mutex_lock(&host->lock);
 582         host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_ON);
 583         mutex_unlock(&host->lock);
 584         memstick_detect_change(host);
 585 }
 586 EXPORT_SYMBOL(memstick_resume_host);
 587
 588 int memstick_register_driver(struct memstick_driver *drv)
 589 {
 590         drv->driver.bus = &memstick_bus_type;
 591
 592         return driver_register(&drv->driver);
 593 }
 594 EXPORT_SYMBOL(memstick_register_driver);
 595
 596 void memstick_unregister_driver(struct memstick_driver *drv)
 597 {
 598         driver_unregister(&drv->driver);
 599 }
 600 EXPORT_SYMBOL(memstick_unregister_driver);
 601
 602
 603 static int __init memstick_init(void)
 604 {
 605         int rc;
 606
 607         workqueue = create_freezeable_workqueue("kmemstick");
 608         if (!workqueue)
 609                 return -ENOMEM;
 610
 611         rc = bus_register(&memstick_bus_type);
 612         if (!rc)
 613                 rc = class_register(&memstick_host_class);
 614
 615         if (!rc)
 616                 return 0;
 617
 618         bus_unregister(&memstick_bus_type);
 619         destroy_workqueue(workqueue);
 620
 621         return rc;
 622 }
 623
 624 static void __exit memstick_exit(void)
 625 {
 626         class_unregister(&memstick_host_class);
 627         bus_unregister(&memstick_bus_type);
 628         destroy_workqueue(workqueue);
 629         idr_destroy(&memstick_host_idr);
 630 }
 631
 632 module_init(memstick_init);
 633 module_exit(memstick_exit);
 634
 635 MODULE_AUTHOR("Alex Dubov");
 636 MODULE_LICENSE("GPL");
 637 MODULE_DESCRIPTION("Sony MemoryStick core driver");