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 #include <linux/slab.h>
  20
  21 #define DRIVER_NAME "memstick"
  22
  23 static unsigned int cmd_retries = 3;
  24 module_param(cmd_retries, uint, 0644);
  25
  26 static struct workqueue_struct *workqueue;
  27 static DEFINE_IDR(memstick_host_idr);
  28 static DEFINE_SPINLOCK(memstick_host_lock);
  29
  30 static int memstick_dev_match(struct memstick_dev *card,
  31                               struct memstick_device_id *id)
  32 {
  33         if (id->match_flags & MEMSTICK_MATCH_ALL) {
  34                 if ((id->type == card->id.type)
  35                     && (id->category == card->id.category)
  36                     && (id->class == card->id.class))
  37                         return 1;
  38         }
  39
  40         return 0;
  41 }
  42
  43 static int memstick_bus_match(struct device *dev, struct device_driver *drv)
  44 {
  45         struct memstick_dev *card = container_of(dev, struct memstick_dev,
  46                                                  dev);
  47         struct memstick_driver *ms_drv = container_of(drv,
  48                                                       struct memstick_driver,
  49                                                       driver);
  50         struct memstick_device_id *ids = ms_drv->id_table;
  51
  52         if (ids) {
  53                 while (ids->match_flags) {
  54                         if (memstick_dev_match(card, ids))
  55                                 return 1;
  56                         ++ids;
  57                 }
  58         }
  59         return 0;
  60 }
  61
  62 static int memstick_uevent(struct device *dev, struct kobj_uevent_env *env)
  63 {
  64         struct memstick_dev *card = container_of(dev, struct memstick_dev,
  65                                                   dev);
  66
  67         if (add_uevent_var(env, "MEMSTICK_TYPE=%02X", card->id.type))
  68                 return -ENOMEM;
  69
  70         if (add_uevent_var(env, "MEMSTICK_CATEGORY=%02X", card->id.category))
  71                 return -ENOMEM;
  72
  73         if (add_uevent_var(env, "MEMSTICK_CLASS=%02X", card->id.class))
  74                 return -ENOMEM;
  75
  76         return 0;
  77 }
  78
  79 static int memstick_device_probe(struct device *dev)
  80 {
  81         struct memstick_dev *card = container_of(dev, struct memstick_dev,
  82                                                  dev);
  83         struct memstick_driver *drv = container_of(dev->driver,
  84                                                    struct memstick_driver,
  85                                                    driver);
  86         int rc = -ENODEV;
  87
  88         if (dev->driver && drv->probe) {
  89                 rc = drv->probe(card);
  90                 if (!rc)
  91                         get_device(dev);
  92         }
  93         return rc;
  94 }
  95
  96 static int memstick_device_remove(struct device *dev)
  97 {
  98         struct memstick_dev *card = container_of(dev, struct memstick_dev,
  99                                                   dev);
 100         struct memstick_driver *drv = container_of(dev->driver,
 101                                                    struct memstick_driver,
 102                                                    driver);
 103
 104         if (dev->driver && drv->remove) {
 105                 drv->remove(card);
 106                 card->dev.driver = NULL;
 107         }
 108
 109         put_device(dev);
 110         return 0;
 111 }
 112
 113 #ifdef CONFIG_PM
 114
 115 static int memstick_device_suspend(struct device *dev, pm_message_t state)
 116 {
 117         struct memstick_dev *card = container_of(dev, struct memstick_dev,
 118                                                   dev);
 119         struct memstick_driver *drv = container_of(dev->driver,
 120                                                    struct memstick_driver,
 121                                                    driver);
 122
 123         if (dev->driver && drv->suspend)
 124                 return drv->suspend(card, state);
 125         return 0;
 126 }
 127
 128 static int memstick_device_resume(struct device *dev)
 129 {
 130         struct memstick_dev *card = container_of(dev, struct memstick_dev,
 131                                                   dev);
 132         struct memstick_driver *drv = container_of(dev->driver,
 133                                                    struct memstick_driver,
 134                                                    driver);
 135
 136         if (dev->driver && drv->resume)
 137                 return drv->resume(card);
 138         return 0;
 139 }
 140
 141 #else
 142
 143 #define memstick_device_suspend NULL
 144 #define memstick_device_resume NULL
 145
 146 #endif /* CONFIG_PM */
 147
 148 #define MEMSTICK_ATTR(name, format)                                           \
 149 static ssize_t name##_show(struct device *dev, struct device_attribute *attr, \
 150                             char *buf)                                        \
 151 {                                                                             \
 152         struct memstick_dev *card = container_of(dev, struct memstick_dev,    \
 153                                                  dev);                        \
 154         return sprintf(buf, format, card->id.name);                           \
 155 }
 156
 157 MEMSTICK_ATTR(type, "%02X");
 158 MEMSTICK_ATTR(category, "%02X");
 159 MEMSTICK_ATTR(class, "%02X");
 160
 161 #define MEMSTICK_ATTR_RO(name) __ATTR(name, S_IRUGO, name##_show, NULL)
 162
 163 static struct device_attribute memstick_dev_attrs[] = {
 164         MEMSTICK_ATTR_RO(type),
 165         MEMSTICK_ATTR_RO(category),
 166         MEMSTICK_ATTR_RO(class),
 167         __ATTR_NULL
 168 };
 169
 170 static struct bus_type memstick_bus_type = {
 171         .name           = "memstick",
 172         .dev_attrs      = memstick_dev_attrs,
 173         .match          = memstick_bus_match,
 174         .uevent         = memstick_uevent,
 175         .probe          = memstick_device_probe,
 176         .remove         = memstick_device_remove,
 177         .suspend        = memstick_device_suspend,
 178         .resume         = memstick_device_resume
 179 };
 180
 181 static void memstick_free(struct device *dev)
 182 {
 183         struct memstick_host *host = container_of(dev, struct memstick_host,
 184                                                   dev);
 185         kfree(host);
 186 }
 187
 188 static struct class memstick_host_class = {
 189         .name        = "memstick_host",
 190         .dev_release = memstick_free
 191 };
 192
 193 static void memstick_free_card(struct device *dev)
 194 {
 195         struct memstick_dev *card = container_of(dev, struct memstick_dev,
 196                                                  dev);
 197         kfree(card);
 198 }
 199
 200 static int memstick_dummy_check(struct memstick_dev *card)
 201 {
 202         return 0;
 203 }
 204
 205 /**
 206  * memstick_detect_change - schedule media detection on memstick host
 207  * @host - host to use
 208  */
 209 void memstick_detect_change(struct memstick_host *host)
 210 {
 211         queue_work(workqueue, &host->media_checker);
 212 }
 213 EXPORT_SYMBOL(memstick_detect_change);
 214
 215 /**
 216  * memstick_next_req - called by host driver to obtain next request to process
 217  * @host - host to use
 218  * @mrq - pointer to stick the request to
 219  *
 220  * Host calls this function from idle state (*mrq == NULL) or after finishing
 221  * previous request (*mrq should point to it). If previous request was
 222  * unsuccessful, it is retried for predetermined number of times. Return value
 223  * of 0 means that new request was assigned to the host.
 224  */
 225 int memstick_next_req(struct memstick_host *host, struct memstick_request **mrq)
 226 {
 227         int rc = -ENXIO;
 228
 229         if ((*mrq) && (*mrq)->error && host->retries) {
 230                 (*mrq)->error = rc;
 231                 host->retries--;
 232                 return 0;
 233         }
 234
 235         if (host->card && host->card->next_request)
 236                 rc = host->card->next_request(host->card, mrq);
 237
 238         if (!rc)
 239                 host->retries = cmd_retries > 1 ? cmd_retries - 1 : 1;
 240         else
 241                 *mrq = NULL;
 242
 243         return rc;
 244 }
 245 EXPORT_SYMBOL(memstick_next_req);
 246
 247 /**
 248  * memstick_new_req - notify the host that some requests are pending
 249  * @host - host to use
 250  */
 251 void memstick_new_req(struct memstick_host *host)
 252 {
 253         if (host->card) {
 254                 host->retries = cmd_retries;
 255                 INIT_COMPLETION(host->card->mrq_complete);
 256                 host->request(host);
 257         }
 258 }
 259 EXPORT_SYMBOL(memstick_new_req);
 260
 261 /**
 262  * memstick_init_req_sg - set request fields needed for bulk data transfer
 263  * @mrq - request to use
 264  * @tpc - memstick Transport Protocol Command
 265  * @sg - TPC argument
 266  */
 267 void memstick_init_req_sg(struct memstick_request *mrq, unsigned char tpc,
 268                           const struct scatterlist *sg)
 269 {
 270         mrq->tpc = tpc;
 271         if (tpc & 8)
 272                 mrq->data_dir = WRITE;
 273         else
 274                 mrq->data_dir = READ;
 275
 276         mrq->sg = *sg;
 277         mrq->long_data = 1;
 278
 279         if (tpc == MS_TPC_SET_CMD || tpc == MS_TPC_EX_SET_CMD)
 280                 mrq->need_card_int = 1;
 281         else
 282                 mrq->need_card_int = 0;
 283 }
 284 EXPORT_SYMBOL(memstick_init_req_sg);
 285
 286 /**
 287  * memstick_init_req - set request fields needed for short data transfer
 288  * @mrq - request to use
 289  * @tpc - memstick Transport Protocol Command
 290  * @buf - TPC argument buffer
 291  * @length - TPC argument size
 292  *
 293  * The intended use of this function (transfer of data items several bytes
 294  * in size) allows us to just copy the value between request structure and
 295  * user supplied buffer.
 296  */
 297 void memstick_init_req(struct memstick_request *mrq, unsigned char tpc,
 298                        const void *buf, size_t length)
 299 {
 300         mrq->tpc = tpc;
 301         if (tpc & 8)
 302                 mrq->data_dir = WRITE;
 303         else
 304                 mrq->data_dir = READ;
 305
 306         mrq->data_len = length > sizeof(mrq->data) ? sizeof(mrq->data) : length;
 307         if (mrq->data_dir == WRITE)
 308                 memcpy(mrq->data, buf, mrq->data_len);
 309
 310         mrq->long_data = 0;
 311
 312         if (tpc == MS_TPC_SET_CMD || tpc == MS_TPC_EX_SET_CMD)
 313                 mrq->need_card_int = 1;
 314         else
 315                 mrq->need_card_int = 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                         dev_dbg(&card->dev, "if_mode = %02x\n", id_reg.if_mode);
 344                 }
 345                 complete(&card->mrq_complete);
 346                 return -EAGAIN;
 347         }
 348 }
 349
 350 static int h_memstick_set_rw_addr(struct memstick_dev *card,
 351                                   struct memstick_request **mrq)
 352 {
 353         if (!(*mrq)) {
 354                 memstick_init_req(&card->current_mrq, MS_TPC_SET_RW_REG_ADRS,
 355                                   (char *)&card->reg_addr,
 356                                   sizeof(card->reg_addr));
 357                 *mrq = &card->current_mrq;
 358                 return 0;
 359         } else {
 360                 complete(&card->mrq_complete);
 361                 return -EAGAIN;
 362         }
 363 }
 364
 365 /**
 366  * memstick_set_rw_addr - issue SET_RW_REG_ADDR request and wait for it to
 367  *                        complete
 368  * @card - media device to use
 369  */
 370 int memstick_set_rw_addr(struct memstick_dev *card)
 371 {
 372         card->next_request = h_memstick_set_rw_addr;
 373         memstick_new_req(card->host);
 374         wait_for_completion(&card->mrq_complete);
 375
 376         return card->current_mrq.error;
 377 }
 378 EXPORT_SYMBOL(memstick_set_rw_addr);
 379
 380 static struct memstick_dev *memstick_alloc_card(struct memstick_host *host)
 381 {
 382         struct memstick_dev *card = kzalloc(sizeof(struct memstick_dev),
 383                                             GFP_KERNEL);
 384         struct memstick_dev *old_card = host->card;
 385         struct ms_id_register id_reg;
 386
 387         if (card) {
 388                 card->host = host;
 389                 dev_set_name(&card->dev, "%s", dev_name(&host->dev));
 390                 card->dev.parent = &host->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 int memstick_power_on(struct memstick_host *host)
 422 {
 423         int rc = host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_ON);
 424
 425         if (!rc)
 426                 rc = host->set_param(host, MEMSTICK_INTERFACE, MEMSTICK_SERIAL);
 427
 428         return rc;
 429 }
 430
 431 static void memstick_check(struct work_struct *work)
 432 {
 433         struct memstick_host *host = container_of(work, struct memstick_host,
 434                                                   media_checker);
 435         struct memstick_dev *card;
 436
 437         dev_dbg(&host->dev, "memstick_check started\n");
 438         mutex_lock(&host->lock);
 439         if (!host->card) {
 440                 if (memstick_power_on(host))
 441                         goto out_power_off;
 442         } else if (host->card->stop)
 443                 host->card->stop(host->card);
 444
 445         card = memstick_alloc_card(host);
 446
 447         if (!card) {
 448                 if (host->card) {
 449                         device_unregister(&host->card->dev);
 450                         host->card = NULL;
 451                 }
 452         } else {
 453                 dev_dbg(&host->dev, "new card %02x, %02x, %02x\n",
 454                         card->id.type, card->id.category, card->id.class);
 455                 if (host->card) {
 456                         if (memstick_set_rw_addr(host->card)
 457                             || !memstick_dev_match(host->card, &card->id)
 458                             || !(host->card->check(host->card))) {
 459                                 device_unregister(&host->card->dev);
 460                                 host->card = NULL;
 461                         } else if (host->card->start)
 462                                 host->card->start(host->card);
 463                 }
 464
 465                 if (!host->card) {
 466                         host->card = card;
 467                         if (device_register(&card->dev)) {
 468                                 put_device(&card->dev);
 469                                 kfree(host->card);
 470                                 host->card = NULL;
 471                         }
 472                 } else
 473                         kfree(card);
 474         }
 475
 476 out_power_off:
 477         if (!host->card)
 478                 host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
 479
 480         mutex_unlock(&host->lock);
 481         dev_dbg(&host->dev, "memstick_check finished\n");
 482 }
 483
 484 /**
 485  * memstick_alloc_host - allocate a memstick_host structure
 486  * @extra: size of the user private data to allocate
 487  * @dev: parent device of the host
 488  */
 489 struct memstick_host *memstick_alloc_host(unsigned int extra,
 490                                           struct device *dev)
 491 {
 492         struct memstick_host *host;
 493
 494         host = kzalloc(sizeof(struct memstick_host) + extra, GFP_KERNEL);
 495         if (host) {
 496                 mutex_init(&host->lock);
 497                 INIT_WORK(&host->media_checker, memstick_check);
 498                 host->dev.class = &memstick_host_class;
 499                 host->dev.parent = dev;
 500                 device_initialize(&host->dev);
 501         }
 502         return host;
 503 }
 504 EXPORT_SYMBOL(memstick_alloc_host);
 505
 506 /**
 507  * memstick_add_host - start request processing on memstick host
 508  * @host - host to use
 509  */
 510 int memstick_add_host(struct memstick_host *host)
 511 {
 512         int rc;
 513
 514         while (1) {
 515                 if (!idr_pre_get(&memstick_host_idr, GFP_KERNEL))
 516                         return -ENOMEM;
 517
 518                 spin_lock(&memstick_host_lock);
 519                 rc = idr_get_new(&memstick_host_idr, host, &host->id);
 520                 spin_unlock(&memstick_host_lock);
 521                 if (!rc)
 522                         break;
 523                 else if (rc != -EAGAIN)
 524                         return rc;
 525         }
 526
 527         dev_set_name(&host->dev, "memstick%u", host->id);
 528
 529         rc = device_add(&host->dev);
 530         if (rc) {
 531                 spin_lock(&memstick_host_lock);
 532                 idr_remove(&memstick_host_idr, host->id);
 533                 spin_unlock(&memstick_host_lock);
 534                 return rc;
 535         }
 536
 537         host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
 538         memstick_detect_change(host);
 539         return 0;
 540 }
 541 EXPORT_SYMBOL(memstick_add_host);
 542
 543 /**
 544  * memstick_remove_host - stop request processing on memstick host
 545  * @host - host to use
 546  */
 547 void memstick_remove_host(struct memstick_host *host)
 548 {
 549         flush_workqueue(workqueue);
 550         mutex_lock(&host->lock);
 551         if (host->card)
 552                 device_unregister(&host->card->dev);
 553         host->card = NULL;
 554         host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
 555         mutex_unlock(&host->lock);
 556
 557         spin_lock(&memstick_host_lock);
 558         idr_remove(&memstick_host_idr, host->id);
 559         spin_unlock(&memstick_host_lock);
 560         device_del(&host->dev);
 561 }
 562 EXPORT_SYMBOL(memstick_remove_host);
 563
 564 /**
 565  * memstick_free_host - free memstick host
 566  * @host - host to use
 567  */
 568 void memstick_free_host(struct memstick_host *host)
 569 {
 570         mutex_destroy(&host->lock);
 571         put_device(&host->dev);
 572 }
 573 EXPORT_SYMBOL(memstick_free_host);
 574
 575 /**
 576  * memstick_suspend_host - notify bus driver of host suspension
 577  * @host - host to use
 578  */
 579 void memstick_suspend_host(struct memstick_host *host)
 580 {
 581         mutex_lock(&host->lock);
 582         host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
 583         mutex_unlock(&host->lock);
 584 }
 585 EXPORT_SYMBOL(memstick_suspend_host);
 586
 587 /**
 588  * memstick_resume_host - notify bus driver of host resumption
 589  * @host - host to use
 590  */
 591 void memstick_resume_host(struct memstick_host *host)
 592 {
 593         int rc = 0;
 594
 595         mutex_lock(&host->lock);
 596         if (host->card)
 597                 rc = memstick_power_on(host);
 598         mutex_unlock(&host->lock);
 599
 600         if (!rc)
 601                 memstick_detect_change(host);
 602 }
 603 EXPORT_SYMBOL(memstick_resume_host);
 604
 605 int memstick_register_driver(struct memstick_driver *drv)
 606 {
 607         drv->driver.bus = &memstick_bus_type;
 608
 609         return driver_register(&drv->driver);
 610 }
 611 EXPORT_SYMBOL(memstick_register_driver);
 612
 613 void memstick_unregister_driver(struct memstick_driver *drv)
 614 {
 615         driver_unregister(&drv->driver);
 616 }
 617 EXPORT_SYMBOL(memstick_unregister_driver);
 618
 619
 620 static int __init memstick_init(void)
 621 {
 622         int rc;
 623
 624         workqueue = create_freezable_workqueue("kmemstick");
 625         if (!workqueue)
 626                 return -ENOMEM;
 627
 628         rc = bus_register(&memstick_bus_type);
 629         if (!rc)
 630                 rc = class_register(&memstick_host_class);
 631
 632         if (!rc)
 633                 return 0;
 634
 635         bus_unregister(&memstick_bus_type);
 636         destroy_workqueue(workqueue);
 637
 638         return rc;
 639 }
 640
 641 static void __exit memstick_exit(void)
 642 {
 643         class_unregister(&memstick_host_class);
 644         bus_unregister(&memstick_bus_type);
 645         destroy_workqueue(workqueue);
 646         idr_destroy(&memstick_host_idr);
 647 }
 648
 649 module_init(memstick_init);
 650 module_exit(memstick_exit);
 651
 652 MODULE_AUTHOR("Alex Dubov");
 653 MODULE_LICENSE("GPL");
 654 MODULE_DESCRIPTION("Sony MemoryStick core driver");