drivers/memstick/core/memstick.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  Sony MemoryStick support
   4  *
   5  *  Copyright (C) 2007 Alex Dubov <[email protected]>
   6  *
   7  * Special thanks to Carlos Corbacho for providing various MemoryStick cards
   8  * that made this driver possible.
   9  */
  10
  11 #include <linux/memstick.h>
  12 #include <linux/idr.h>
  13 #include <linux/fs.h>
  14 #include <linux/delay.h>
  15 #include <linux/slab.h>
  16 #include <linux/module.h>
  17 #include <linux/pm_runtime.h>
  18
  19 #define DRIVER_NAME "memstick"
  20
  21 static unsigned int cmd_retries = 3;
  22 module_param(cmd_retries, uint, 0644);
  23
  24 static struct workqueue_struct *workqueue;
  25 static DEFINE_IDR(memstick_host_idr);
  26 static DEFINE_SPINLOCK(memstick_host_lock);
  27
  28 static int memstick_dev_match(struct memstick_dev *card,
  29                               struct memstick_device_id *id)
  30 {
  31         if (id->match_flags & MEMSTICK_MATCH_ALL) {
  32                 if ((id->type == card->id.type)
  33                     && (id->category == card->id.category)
  34                     && (id->class == card->id.class))
  35                         return 1;
  36         }
  37
  38         return 0;
  39 }
  40
  41 static int memstick_bus_match(struct device *dev, struct device_driver *drv)
  42 {
  43         struct memstick_dev *card = container_of(dev, struct memstick_dev,
  44                                                  dev);
  45         struct memstick_driver *ms_drv = container_of(drv,
  46                                                       struct memstick_driver,
  47                                                       driver);
  48         struct memstick_device_id *ids = ms_drv->id_table;
  49
  50         if (ids) {
  51                 while (ids->match_flags) {
  52                         if (memstick_dev_match(card, ids))
  53                                 return 1;
  54                         ++ids;
  55                 }
  56         }
  57         return 0;
  58 }
  59
  60 static int memstick_uevent(struct device *dev, struct kobj_uevent_env *env)
  61 {
  62         struct memstick_dev *card = container_of(dev, struct memstick_dev,
  63                                                   dev);
  64
  65         if (add_uevent_var(env, "MEMSTICK_TYPE=%02X", card->id.type))
  66                 return -ENOMEM;
  67
  68         if (add_uevent_var(env, "MEMSTICK_CATEGORY=%02X", card->id.category))
  69                 return -ENOMEM;
  70
  71         if (add_uevent_var(env, "MEMSTICK_CLASS=%02X", card->id.class))
  72                 return -ENOMEM;
  73
  74         return 0;
  75 }
  76
  77 static int memstick_device_probe(struct device *dev)
  78 {
  79         struct memstick_dev *card = container_of(dev, struct memstick_dev,
  80                                                  dev);
  81         struct memstick_driver *drv = container_of(dev->driver,
  82                                                    struct memstick_driver,
  83                                                    driver);
  84         int rc = -ENODEV;
  85
  86         if (dev->driver && drv->probe) {
  87                 rc = drv->probe(card);
  88                 if (!rc)
  89                         get_device(dev);
  90         }
  91         return rc;
  92 }
  93
  94 static void memstick_device_remove(struct device *dev)
  95 {
  96         struct memstick_dev *card = container_of(dev, struct memstick_dev,
  97                                                   dev);
  98         struct memstick_driver *drv = container_of(dev->driver,
  99                                                    struct memstick_driver,
 100                                                    driver);
 101
 102         if (dev->driver && drv->remove) {
 103                 drv->remove(card);
 104                 card->dev.driver = NULL;
 105         }
 106
 107         put_device(dev);
 108 }
 109
 110 #ifdef CONFIG_PM
 111
 112 static int memstick_device_suspend(struct device *dev, pm_message_t state)
 113 {
 114         struct memstick_dev *card = container_of(dev, struct memstick_dev,
 115                                                   dev);
 116         struct memstick_driver *drv = container_of(dev->driver,
 117                                                    struct memstick_driver,
 118                                                    driver);
 119
 120         if (dev->driver && drv->suspend)
 121                 return drv->suspend(card, state);
 122         return 0;
 123 }
 124
 125 static int memstick_device_resume(struct device *dev)
 126 {
 127         struct memstick_dev *card = container_of(dev, struct memstick_dev,
 128                                                   dev);
 129         struct memstick_driver *drv = container_of(dev->driver,
 130                                                    struct memstick_driver,
 131                                                    driver);
 132
 133         if (dev->driver && drv->resume)
 134                 return drv->resume(card);
 135         return 0;
 136 }
 137
 138 #else
 139
 140 #define memstick_device_suspend NULL
 141 #define memstick_device_resume NULL
 142
 143 #endif /* CONFIG_PM */
 144
 145 #define MEMSTICK_ATTR(name, format)                                           \
 146 static ssize_t name##_show(struct device *dev, struct device_attribute *attr, \
 147                             char *buf)                                        \
 148 {                                                                             \
 149         struct memstick_dev *card = container_of(dev, struct memstick_dev,    \
 150                                                  dev);                        \
 151         return sprintf(buf, format, card->id.name);                           \
 152 }                                                                             \
 153 static DEVICE_ATTR_RO(name);
 154
 155 MEMSTICK_ATTR(type, "%02X");
 156 MEMSTICK_ATTR(category, "%02X");
 157 MEMSTICK_ATTR(class, "%02X");
 158
 159 static struct attribute *memstick_dev_attrs[] = {
 160         &dev_attr_type.attr,
 161         &dev_attr_category.attr,
 162         &dev_attr_class.attr,
 163         NULL,
 164 };
 165 ATTRIBUTE_GROUPS(memstick_dev);
 166
 167 static struct bus_type memstick_bus_type = {
 168         .name           = "memstick",
 169         .dev_groups     = memstick_dev_groups,
 170         .match          = memstick_bus_match,
 171         .uevent         = memstick_uevent,
 172         .probe          = memstick_device_probe,
 173         .remove         = memstick_device_remove,
 174         .suspend        = memstick_device_suspend,
 175         .resume         = memstick_device_resume
 176 };
 177
 178 static void memstick_free(struct device *dev)
 179 {
 180         struct memstick_host *host = container_of(dev, struct memstick_host,
 181                                                   dev);
 182         kfree(host);
 183 }
 184
 185 static struct class memstick_host_class = {
 186         .name        = "memstick_host",
 187         .dev_release = memstick_free
 188 };
 189
 190 static void memstick_free_card(struct device *dev)
 191 {
 192         struct memstick_dev *card = container_of(dev, struct memstick_dev,
 193                                                  dev);
 194         kfree(card);
 195 }
 196
 197 static int memstick_dummy_check(struct memstick_dev *card)
 198 {
 199         return 0;
 200 }
 201
 202 /**
 203  * memstick_detect_change - schedule media detection on memstick host
 204  * @host - host to use
 205  */
 206 void memstick_detect_change(struct memstick_host *host)
 207 {
 208         queue_work(workqueue, &host->media_checker);
 209 }
 210 EXPORT_SYMBOL(memstick_detect_change);
 211
 212 /**
 213  * memstick_next_req - called by host driver to obtain next request to process
 214  * @host - host to use
 215  * @mrq - pointer to stick the request to
 216  *
 217  * Host calls this function from idle state (*mrq == NULL) or after finishing
 218  * previous request (*mrq should point to it). If previous request was
 219  * unsuccessful, it is retried for predetermined number of times. Return value
 220  * of 0 means that new request was assigned to the host.
 221  */
 222 int memstick_next_req(struct memstick_host *host, struct memstick_request **mrq)
 223 {
 224         int rc = -ENXIO;
 225
 226         if ((*mrq) && (*mrq)->error && host->retries) {
 227                 (*mrq)->error = rc;
 228                 host->retries--;
 229                 return 0;
 230         }
 231
 232         if (host->card && host->card->next_request)
 233                 rc = host->card->next_request(host->card, mrq);
 234
 235         if (!rc)
 236                 host->retries = cmd_retries > 1 ? cmd_retries - 1 : 1;
 237         else
 238                 *mrq = NULL;
 239
 240         return rc;
 241 }
 242 EXPORT_SYMBOL(memstick_next_req);
 243
 244 /**
 245  * memstick_new_req - notify the host that some requests are pending
 246  * @host - host to use
 247  */
 248 void memstick_new_req(struct memstick_host *host)
 249 {
 250         if (host->card) {
 251                 host->retries = cmd_retries;
 252                 reinit_completion(&host->card->mrq_complete);
 253                 host->request(host);
 254         }
 255 }
 256 EXPORT_SYMBOL(memstick_new_req);
 257
 258 /**
 259  * memstick_init_req_sg - set request fields needed for bulk data transfer
 260  * @mrq - request to use
 261  * @tpc - memstick Transport Protocol Command
 262  * @sg - TPC argument
 263  */
 264 void memstick_init_req_sg(struct memstick_request *mrq, unsigned char tpc,
 265                           const struct scatterlist *sg)
 266 {
 267         mrq->tpc = tpc;
 268         if (tpc & 8)
 269                 mrq->data_dir = WRITE;
 270         else
 271                 mrq->data_dir = READ;
 272
 273         mrq->sg = *sg;
 274         mrq->long_data = 1;
 275
 276         if (tpc == MS_TPC_SET_CMD || tpc == MS_TPC_EX_SET_CMD)
 277                 mrq->need_card_int = 1;
 278         else
 279                 mrq->need_card_int = 0;
 280 }
 281 EXPORT_SYMBOL(memstick_init_req_sg);
 282
 283 /**
 284  * memstick_init_req - set request fields needed for short data transfer
 285  * @mrq - request to use
 286  * @tpc - memstick Transport Protocol Command
 287  * @buf - TPC argument buffer
 288  * @length - TPC argument size
 289  *
 290  * The intended use of this function (transfer of data items several bytes
 291  * in size) allows us to just copy the value between request structure and
 292  * user supplied buffer.
 293  */
 294 void memstick_init_req(struct memstick_request *mrq, unsigned char tpc,
 295                        const void *buf, size_t length)
 296 {
 297         mrq->tpc = tpc;
 298         if (tpc & 8)
 299                 mrq->data_dir = WRITE;
 300         else
 301                 mrq->data_dir = READ;
 302
 303         mrq->data_len = length > sizeof(mrq->data) ? sizeof(mrq->data) : length;
 304         if (mrq->data_dir == WRITE)
 305                 memcpy(mrq->data, buf, mrq->data_len);
 306
 307         mrq->long_data = 0;
 308
 309         if (tpc == MS_TPC_SET_CMD || tpc == MS_TPC_EX_SET_CMD)
 310                 mrq->need_card_int = 1;
 311         else
 312                 mrq->need_card_int = 0;
 313 }
 314 EXPORT_SYMBOL(memstick_init_req);
 315
 316 /*
 317  * Functions prefixed with "h_" are protocol callbacks. They can be called from
 318  * interrupt context. Return value of 0 means that request processing is still
 319  * ongoing, while special error value of -EAGAIN means that current request is
 320  * finished (and request processor should come back some time later).
 321  */
 322
 323 static int h_memstick_read_dev_id(struct memstick_dev *card,
 324                                   struct memstick_request **mrq)
 325 {
 326         struct ms_id_register id_reg;
 327
 328         if (!(*mrq)) {
 329                 memstick_init_req(&card->current_mrq, MS_TPC_READ_REG, &id_reg,
 330                                   sizeof(struct ms_id_register));
 331                 *mrq = &card->current_mrq;
 332                 return 0;
 333         }
 334         if (!(*mrq)->error) {
 335                 memcpy(&id_reg, (*mrq)->data, sizeof(id_reg));
 336                 card->id.match_flags = MEMSTICK_MATCH_ALL;
 337                 card->id.type = id_reg.type;
 338                 card->id.category = id_reg.category;
 339                 card->id.class = id_reg.class;
 340                 dev_dbg(&card->dev, "if_mode = %02x\n", id_reg.if_mode);
 341         }
 342         complete(&card->mrq_complete);
 343         return -EAGAIN;
 344 }
 345
 346 static int h_memstick_set_rw_addr(struct memstick_dev *card,
 347                                   struct memstick_request **mrq)
 348 {
 349         if (!(*mrq)) {
 350                 memstick_init_req(&card->current_mrq, MS_TPC_SET_RW_REG_ADRS,
 351                                   (char *)&card->reg_addr,
 352                                   sizeof(card->reg_addr));
 353                 *mrq = &card->current_mrq;
 354                 return 0;
 355         } else {
 356                 complete(&card->mrq_complete);
 357                 return -EAGAIN;
 358         }
 359 }
 360
 361 /**
 362  * memstick_set_rw_addr - issue SET_RW_REG_ADDR request and wait for it to
 363  *                        complete
 364  * @card - media device to use
 365  */
 366 int memstick_set_rw_addr(struct memstick_dev *card)
 367 {
 368         card->next_request = h_memstick_set_rw_addr;
 369         memstick_new_req(card->host);
 370         wait_for_completion(&card->mrq_complete);
 371
 372         return card->current_mrq.error;
 373 }
 374 EXPORT_SYMBOL(memstick_set_rw_addr);
 375
 376 static struct memstick_dev *memstick_alloc_card(struct memstick_host *host)
 377 {
 378         struct memstick_dev *card = kzalloc(sizeof(struct memstick_dev),
 379                                             GFP_KERNEL);
 380         struct memstick_dev *old_card = host->card;
 381         struct ms_id_register id_reg;
 382
 383         if (card) {
 384                 card->host = host;
 385                 dev_set_name(&card->dev, "%s", dev_name(&host->dev));
 386                 card->dev.parent = &host->dev;
 387                 card->dev.bus = &memstick_bus_type;
 388                 card->dev.release = memstick_free_card;
 389                 card->check = memstick_dummy_check;
 390
 391                 card->reg_addr.r_offset = offsetof(struct ms_register, id);
 392                 card->reg_addr.r_length = sizeof(id_reg);
 393                 card->reg_addr.w_offset = offsetof(struct ms_register, id);
 394                 card->reg_addr.w_length = sizeof(id_reg);
 395
 396                 init_completion(&card->mrq_complete);
 397
 398                 host->card = card;
 399                 if (memstick_set_rw_addr(card))
 400                         goto err_out;
 401
 402                 card->next_request = h_memstick_read_dev_id;
 403                 memstick_new_req(host);
 404                 wait_for_completion(&card->mrq_complete);
 405
 406                 if (card->current_mrq.error)
 407                         goto err_out;
 408         }
 409         host->card = old_card;
 410         return card;
 411 err_out:
 412         host->card = old_card;
 413         kfree(card);
 414         return NULL;
 415 }
 416
 417 static int memstick_power_on(struct memstick_host *host)
 418 {
 419         int rc = host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_ON);
 420
 421         if (!rc)
 422                 rc = host->set_param(host, MEMSTICK_INTERFACE, MEMSTICK_SERIAL);
 423
 424         return rc;
 425 }
 426
 427 static void memstick_check(struct work_struct *work)
 428 {
 429         struct memstick_host *host = container_of(work, struct memstick_host,
 430                                                   media_checker);
 431         struct memstick_dev *card;
 432
 433         dev_dbg(&host->dev, "memstick_check started\n");
 434         pm_runtime_get_noresume(host->dev.parent);
 435         mutex_lock(&host->lock);
 436         if (!host->card) {
 437                 if (memstick_power_on(host))
 438                         goto out_power_off;
 439         } else if (host->card->stop)
 440                 host->card->stop(host->card);
 441
 442         if (host->removing)
 443                 goto out_power_off;
 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                                 host->card = NULL;
 470                         }
 471                 } else
 472                         kfree(card);
 473         }
 474
 475 out_power_off:
 476         if (!host->card)
 477                 host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
 478
 479         mutex_unlock(&host->lock);
 480         pm_runtime_put(host->dev.parent);
 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         idr_preload(GFP_KERNEL);
 515         spin_lock(&memstick_host_lock);
 516
 517         rc = idr_alloc(&memstick_host_idr, host, 0, 0, GFP_NOWAIT);
 518         if (rc >= 0)
 519                 host->id = rc;
 520
 521         spin_unlock(&memstick_host_lock);
 522         idr_preload_end();
 523         if (rc < 0)
 524                 return rc;
 525
 526         dev_set_name(&host->dev, "memstick%u", host->id);
 527
 528         rc = device_add(&host->dev);
 529         if (rc) {
 530                 spin_lock(&memstick_host_lock);
 531                 idr_remove(&memstick_host_idr, host->id);
 532                 spin_unlock(&memstick_host_lock);
 533                 return rc;
 534         }
 535
 536         host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
 537         memstick_detect_change(host);
 538         return 0;
 539 }
 540 EXPORT_SYMBOL(memstick_add_host);
 541
 542 /**
 543  * memstick_remove_host - stop request processing on memstick host
 544  * @host - host to use
 545  */
 546 void memstick_remove_host(struct memstick_host *host)
 547 {
 548         host->removing = 1;
 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                 goto error_destroy_workqueue;
 631
 632         rc = class_register(&memstick_host_class);
 633         if (rc)
 634                 goto error_bus_unregister;
 635
 636         return 0;
 637
 638 error_bus_unregister:
 639         bus_unregister(&memstick_bus_type);
 640 error_destroy_workqueue:
 641         destroy_workqueue(workqueue);
 642
 643         return rc;
 644 }
 645
 646 static void __exit memstick_exit(void)
 647 {
 648         class_unregister(&memstick_host_class);
 649         bus_unregister(&memstick_bus_type);
 650         destroy_workqueue(workqueue);
 651         idr_destroy(&memstick_host_idr);
 652 }
 653
 654 module_init(memstick_init);
 655 module_exit(memstick_exit);
 656
 657 MODULE_AUTHOR("Alex Dubov");
 658 MODULE_LICENSE("GPL");
 659 MODULE_DESCRIPTION("Sony MemoryStick core driver");