drivers/usb/gadget/udc/udc-core.c

   1 /**
   2  * udc.c - Core UDC Framework
   3  *
   4  * Copyright (C) 2010 Texas Instruments
   5  * Author: Felipe Balbi <balbi@ti.com>
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2  of
   9  * the License as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <linux/kernel.h>
  21 #include <linux/module.h>
  22 #include <linux/device.h>
  23 #include <linux/list.h>
  24 #include <linux/err.h>
  25 #include <linux/dma-mapping.h>
  26 #include <linux/workqueue.h>
  27
  28 #include <linux/usb/ch9.h>
  29 #include <linux/usb/gadget.h>
  30 #include <linux/usb.h>
  31
  32 /**
  33  * struct usb_udc - describes one usb device controller
  34  * @driver - the gadget driver pointer. For use by the class code
  35  * @dev - the child device to the actual controller
  36  * @gadget - the gadget. For use by the class code
  37  * @list - for use by the udc class driver
  38  * @vbus - for udcs who care about vbus status, this value is real vbus status;
  39  * for udcs who do not care about vbus status, this value is always true
  40  *
  41  * This represents the internal data structure which is used by the UDC-class
  42  * to hold information about udc driver and gadget together.
  43  */
  44 struct usb_udc {
  45         struct usb_gadget_driver        *driver;
  46         struct usb_gadget               *gadget;
  47         struct device                   dev;
  48         struct list_head                list;
  49         bool                            vbus;
  50 };
  51
  52 static struct class *udc_class;
  53 static LIST_HEAD(udc_list);
  54 static LIST_HEAD(gadget_driver_pending_list);
  55 static DEFINE_MUTEX(udc_lock);
  56
  57 static int udc_bind_to_driver(struct usb_udc *udc,
  58                 struct usb_gadget_driver *driver);
  59
  60 /* ------------------------------------------------------------------------- */
  61
  62 #ifdef  CONFIG_HAS_DMA
  63
  64 int usb_gadget_map_request_by_dev(struct device *dev,
  65                 struct usb_request *req, int is_in)
  66 {
  67         if (req->length == 0)
  68                 return 0;
  69
  70         if (req->num_sgs) {
  71                 int     mapped;
  72
  73                 mapped = dma_map_sg(dev, req->sg, req->num_sgs,
  74                                 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
  75                 if (mapped == 0) {
  76                         dev_err(dev, "failed to map SGs\n");
  77                         return -EFAULT;
  78                 }
  79
  80                 req->num_mapped_sgs = mapped;
  81         } else {
  82                 req->dma = dma_map_single(dev, req->buf, req->length,
  83                                 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
  84
  85                 if (dma_mapping_error(dev, req->dma)) {
  86                         dev_err(dev, "failed to map buffer\n");
  87                         return -EFAULT;
  88                 }
  89         }
  90
  91         return 0;
  92 }
  93 EXPORT_SYMBOL_GPL(usb_gadget_map_request_by_dev);
  94
  95 int usb_gadget_map_request(struct usb_gadget *gadget,
  96                 struct usb_request *req, int is_in)
  97 {
  98         return usb_gadget_map_request_by_dev(gadget->dev.parent, req, is_in);
  99 }
 100 EXPORT_SYMBOL_GPL(usb_gadget_map_request);
 101
 102 void usb_gadget_unmap_request_by_dev(struct device *dev,
 103                 struct usb_request *req, int is_in)
 104 {
 105         if (req->length == 0)
 106                 return;
 107
 108         if (req->num_mapped_sgs) {
 109                 dma_unmap_sg(dev, req->sg, req->num_mapped_sgs,
 110                                 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
 111
 112                 req->num_mapped_sgs = 0;
 113         } else {
 114                 dma_unmap_single(dev, req->dma, req->length,
 115                                 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
 116         }
 117 }
 118 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request_by_dev);
 119
 120 void usb_gadget_unmap_request(struct usb_gadget *gadget,
 121                 struct usb_request *req, int is_in)
 122 {
 123         usb_gadget_unmap_request_by_dev(gadget->dev.parent, req, is_in);
 124 }
 125 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
 126
 127 #endif  /* CONFIG_HAS_DMA */
 128
 129 /* ------------------------------------------------------------------------- */
 130
 131 /**
 132  * usb_gadget_giveback_request - give the request back to the gadget layer
 133  * Context: in_interrupt()
 134  *
 135  * This is called by device controller drivers in order to return the
 136  * completed request back to the gadget layer.
 137  */
 138 void usb_gadget_giveback_request(struct usb_ep *ep,
 139                 struct usb_request *req)
 140 {
 141         if (likely(req->status == 0))
 142                 usb_led_activity(USB_LED_EVENT_GADGET);
 143
 144         req->complete(ep, req);
 145 }
 146 EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
 147
 148 /* ------------------------------------------------------------------------- */
 149
 150 /**
 151  * gadget_find_ep_by_name - returns ep whose name is the same as sting passed
 152  *      in second parameter or NULL if searched endpoint not found
 153  * @g: controller to check for quirk
 154  * @name: name of searched endpoint
 155  */
 156 struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g, const char *name)
 157 {
 158         struct usb_ep *ep;
 159
 160         gadget_for_each_ep(ep, g) {
 161                 if (!strcmp(ep->name, name))
 162                         return ep;
 163         }
 164
 165         return NULL;
 166 }
 167 EXPORT_SYMBOL_GPL(gadget_find_ep_by_name);
 168
 169 /* ------------------------------------------------------------------------- */
 170
 171 int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
 172                 struct usb_ep *ep, struct usb_endpoint_descriptor *desc,
 173                 struct usb_ss_ep_comp_descriptor *ep_comp)
 174 {
 175         u8              type;
 176         u16             max;
 177         int             num_req_streams = 0;
 178
 179         /* endpoint already claimed? */
 180         if (ep->claimed)
 181                 return 0;
 182
 183         type = usb_endpoint_type(desc);
 184         max = 0x7ff & usb_endpoint_maxp(desc);
 185
 186         if (usb_endpoint_dir_in(desc) && !ep->caps.dir_in)
 187                 return 0;
 188         if (usb_endpoint_dir_out(desc) && !ep->caps.dir_out)
 189                 return 0;
 190
 191         if (max > ep->maxpacket_limit)
 192                 return 0;
 193
 194         /* "high bandwidth" works only at high speed */
 195         if (!gadget_is_dualspeed(gadget) && usb_endpoint_maxp(desc) & (3<<11))
 196                 return 0;
 197
 198         switch (type) {
 199         case USB_ENDPOINT_XFER_CONTROL:
 200                 /* only support ep0 for portable CONTROL traffic */
 201                 return 0;
 202         case USB_ENDPOINT_XFER_ISOC:
 203                 if (!ep->caps.type_iso)
 204                         return 0;
 205                 /* ISO:  limit 1023 bytes full speed, 1024 high/super speed */
 206                 if (!gadget_is_dualspeed(gadget) && max > 1023)
 207                         return 0;
 208                 break;
 209         case USB_ENDPOINT_XFER_BULK:
 210                 if (!ep->caps.type_bulk)
 211                         return 0;
 212                 if (ep_comp && gadget_is_superspeed(gadget)) {
 213                         /* Get the number of required streams from the
 214                          * EP companion descriptor and see if the EP
 215                          * matches it
 216                          */
 217                         num_req_streams = ep_comp->bmAttributes & 0x1f;
 218                         if (num_req_streams > ep->max_streams)
 219                                 return 0;
 220                 }
 221                 break;
 222         case USB_ENDPOINT_XFER_INT:
 223                 /* Bulk endpoints handle interrupt transfers,
 224                  * except the toggle-quirky iso-synch kind
 225                  */
 226                 if (!ep->caps.type_int && !ep->caps.type_bulk)
 227                         return 0;
 228                 /* INT:  limit 64 bytes full speed, 1024 high/super speed */
 229                 if (!gadget_is_dualspeed(gadget) && max > 64)
 230                         return 0;
 231                 break;
 232         }
 233
 234         return 1;
 235 }
 236 EXPORT_SYMBOL_GPL(usb_gadget_ep_match_desc);
 237
 238 /* ------------------------------------------------------------------------- */
 239
 240 static void usb_gadget_state_work(struct work_struct *work)
 241 {
 242         struct usb_gadget *gadget = work_to_gadget(work);
 243         struct usb_udc *udc = gadget->udc;
 244
 245         if (udc)
 246                 sysfs_notify(&udc->dev.kobj, NULL, "state");
 247 }
 248
 249 void usb_gadget_set_state(struct usb_gadget *gadget,
 250                 enum usb_device_state state)
 251 {
 252         gadget->state = state;
 253         schedule_work(&gadget->work);
 254 }
 255 EXPORT_SYMBOL_GPL(usb_gadget_set_state);
 256
 257 /* ------------------------------------------------------------------------- */
 258
 259 static void usb_udc_connect_control(struct usb_udc *udc)
 260 {
 261         if (udc->vbus)
 262                 usb_gadget_connect(udc->gadget);
 263         else
 264                 usb_gadget_disconnect(udc->gadget);
 265 }
 266
 267 /**
 268  * usb_udc_vbus_handler - updates the udc core vbus status, and try to
 269  * connect or disconnect gadget
 270  * @gadget: The gadget which vbus change occurs
 271  * @status: The vbus status
 272  *
 273  * The udc driver calls it when it wants to connect or disconnect gadget
 274  * according to vbus status.
 275  */
 276 void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status)
 277 {
 278         struct usb_udc *udc = gadget->udc;
 279
 280         if (udc) {
 281                 udc->vbus = status;
 282                 usb_udc_connect_control(udc);
 283         }
 284 }
 285 EXPORT_SYMBOL_GPL(usb_udc_vbus_handler);
 286
 287 /**
 288  * usb_gadget_udc_reset - notifies the udc core that bus reset occurs
 289  * @gadget: The gadget which bus reset occurs
 290  * @driver: The gadget driver we want to notify
 291  *
 292  * If the udc driver has bus reset handler, it needs to call this when the bus
 293  * reset occurs, it notifies the gadget driver that the bus reset occurs as
 294  * well as updates gadget state.
 295  */
 296 void usb_gadget_udc_reset(struct usb_gadget *gadget,
 297                 struct usb_gadget_driver *driver)
 298 {
 299         driver->reset(gadget);
 300         usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
 301 }
 302 EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);
 303
 304 /**
 305  * usb_gadget_udc_start - tells usb device controller to start up
 306  * @udc: The UDC to be started
 307  *
 308  * This call is issued by the UDC Class driver when it's about
 309  * to register a gadget driver to the device controller, before
 310  * calling gadget driver's bind() method.
 311  *
 312  * It allows the controller to be powered off until strictly
 313  * necessary to have it powered on.
 314  *
 315  * Returns zero on success, else negative errno.
 316  */
 317 static inline int usb_gadget_udc_start(struct usb_udc *udc)
 318 {
 319         return udc->gadget->ops->udc_start(udc->gadget, udc->driver);
 320 }
 321
 322 /**
 323  * usb_gadget_udc_stop - tells usb device controller we don't need it anymore
 324  * @gadget: The device we want to stop activity
 325  * @driver: The driver to unbind from @gadget
 326  *
 327  * This call is issued by the UDC Class driver after calling
 328  * gadget driver's unbind() method.
 329  *
 330  * The details are implementation specific, but it can go as
 331  * far as powering off UDC completely and disable its data
 332  * line pullups.
 333  */
 334 static inline void usb_gadget_udc_stop(struct usb_udc *udc)
 335 {
 336         udc->gadget->ops->udc_stop(udc->gadget);
 337 }
 338
 339 /**
 340  * usb_udc_release - release the usb_udc struct
 341  * @dev: the dev member within usb_udc
 342  *
 343  * This is called by driver's core in order to free memory once the last
 344  * reference is released.
 345  */
 346 static void usb_udc_release(struct device *dev)
 347 {
 348         struct usb_udc *udc;
 349
 350         udc = container_of(dev, struct usb_udc, dev);
 351         dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
 352         kfree(udc);
 353 }
 354
 355 static const struct attribute_group *usb_udc_attr_groups[];
 356
 357 static void usb_udc_nop_release(struct device *dev)
 358 {
 359         dev_vdbg(dev, "%s\n", __func__);
 360 }
 361
 362 /**
 363  * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
 364  * @parent: the parent device to this udc. Usually the controller driver's
 365  * device.
 366  * @gadget: the gadget to be added to the list.
 367  * @release: a gadget release function.
 368  *
 369  * Returns zero on success, negative errno otherwise.
 370  */
 371 int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
 372                 void (*release)(struct device *dev))
 373 {
 374         struct usb_udc          *udc;
 375         struct usb_gadget_driver *driver;
 376         int                     ret = -ENOMEM;
 377
 378         udc = kzalloc(sizeof(*udc), GFP_KERNEL);
 379         if (!udc)
 380                 goto err1;
 381
 382         dev_set_name(&gadget->dev, "gadget");
 383         INIT_WORK(&gadget->work, usb_gadget_state_work);
 384         gadget->dev.parent = parent;
 385
 386         if (release)
 387                 gadget->dev.release = release;
 388         else
 389                 gadget->dev.release = usb_udc_nop_release;
 390
 391         ret = device_register(&gadget->dev);
 392         if (ret)
 393                 goto err2;
 394
 395         device_initialize(&udc->dev);
 396         udc->dev.release = usb_udc_release;
 397         udc->dev.class = udc_class;
 398         udc->dev.groups = usb_udc_attr_groups;
 399         udc->dev.parent = parent;
 400         ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
 401         if (ret)
 402                 goto err3;
 403
 404         udc->gadget = gadget;
 405         gadget->udc = udc;
 406
 407         mutex_lock(&udc_lock);
 408         list_add_tail(&udc->list, &udc_list);
 409
 410         ret = device_add(&udc->dev);
 411         if (ret)
 412                 goto err4;
 413
 414         usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
 415         udc->vbus = true;
 416
 417         /* pick up one of pending gadget drivers */
 418         list_for_each_entry(driver, &gadget_driver_pending_list, pending) {
 419                 if (!driver->udc_name || strcmp(driver->udc_name,
 420                                                 dev_name(&udc->dev)) == 0) {
 421                         ret = udc_bind_to_driver(udc, driver);
 422                         if (ret != -EPROBE_DEFER)
 423                                 list_del(&driver->pending);
 424                         if (ret)
 425                                 goto err4;
 426                         break;
 427                 }
 428         }
 429
 430         mutex_unlock(&udc_lock);
 431
 432         return 0;
 433
 434 err4:
 435         list_del(&udc->list);
 436         mutex_unlock(&udc_lock);
 437
 438 err3:
 439         put_device(&udc->dev);
 440         device_del(&gadget->dev);
 441
 442 err2:
 443         put_device(&gadget->dev);
 444         kfree(udc);
 445
 446 err1:
 447         return ret;
 448 }
 449 EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
 450
 451 /**
 452  * usb_get_gadget_udc_name - get the name of the first UDC controller
 453  * This functions returns the name of the first UDC controller in the system.
 454  * Please note that this interface is usefull only for legacy drivers which
 455  * assume that there is only one UDC controller in the system and they need to
 456  * get its name before initialization. There is no guarantee that the UDC
 457  * of the returned name will be still available, when gadget driver registers
 458  * itself.
 459  *
 460  * Returns pointer to string with UDC controller name on success, NULL
 461  * otherwise. Caller should kfree() returned string.
 462  */
 463 char *usb_get_gadget_udc_name(void)
 464 {
 465         struct usb_udc *udc;
 466         char *name = NULL;
 467
 468         /* For now we take the first available UDC */
 469         mutex_lock(&udc_lock);
 470         list_for_each_entry(udc, &udc_list, list) {
 471                 if (!udc->driver) {
 472                         name = kstrdup(udc->gadget->name, GFP_KERNEL);
 473                         break;
 474                 }
 475         }
 476         mutex_unlock(&udc_lock);
 477         return name;
 478 }
 479 EXPORT_SYMBOL_GPL(usb_get_gadget_udc_name);
 480
 481 /**
 482  * usb_add_gadget_udc - adds a new gadget to the udc class driver list
 483  * @parent: the parent device to this udc. Usually the controller
 484  * driver's device.
 485  * @gadget: the gadget to be added to the list
 486  *
 487  * Returns zero on success, negative errno otherwise.
 488  */
 489 int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
 490 {
 491         return usb_add_gadget_udc_release(parent, gadget, NULL);
 492 }
 493 EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
 494
 495 static void usb_gadget_remove_driver(struct usb_udc *udc)
 496 {
 497         dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
 498                         udc->driver->function);
 499
 500         kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
 501
 502         usb_gadget_disconnect(udc->gadget);
 503         udc->driver->disconnect(udc->gadget);
 504         udc->driver->unbind(udc->gadget);
 505         usb_gadget_udc_stop(udc);
 506
 507         udc->driver = NULL;
 508         udc->dev.driver = NULL;
 509         udc->gadget->dev.driver = NULL;
 510 }
 511
 512 /**
 513  * usb_del_gadget_udc - deletes @udc from udc_list
 514  * @gadget: the gadget to be removed.
 515  *
 516  * This, will call usb_gadget_unregister_driver() if
 517  * the @udc is still busy.
 518  */
 519 void usb_del_gadget_udc(struct usb_gadget *gadget)
 520 {
 521         struct usb_udc *udc = gadget->udc;
 522
 523         if (!udc)
 524                 return;
 525
 526         dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
 527
 528         mutex_lock(&udc_lock);
 529         list_del(&udc->list);
 530
 531         if (udc->driver) {
 532                 struct usb_gadget_driver *driver = udc->driver;
 533
 534                 usb_gadget_remove_driver(udc);
 535                 list_add(&driver->pending, &gadget_driver_pending_list);
 536         }
 537         mutex_unlock(&udc_lock);
 538
 539         kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
 540         flush_work(&gadget->work);
 541         device_unregister(&udc->dev);
 542         device_unregister(&gadget->dev);
 543 }
 544 EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
 545
 546 /* ------------------------------------------------------------------------- */
 547
 548 static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
 549 {
 550         int ret;
 551
 552         dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
 553                         driver->function);
 554
 555         udc->driver = driver;
 556         udc->dev.driver = &driver->driver;
 557         udc->gadget->dev.driver = &driver->driver;
 558
 559         ret = driver->bind(udc->gadget, driver);
 560         if (ret)
 561                 goto err1;
 562         ret = usb_gadget_udc_start(udc);
 563         if (ret) {
 564                 driver->unbind(udc->gadget);
 565                 goto err1;
 566         }
 567         usb_udc_connect_control(udc);
 568
 569         kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
 570         return 0;
 571 err1:
 572         if (ret != -EISNAM)
 573                 dev_err(&udc->dev, "failed to start %s: %d\n",
 574                         udc->driver->function, ret);
 575         udc->driver = NULL;
 576         udc->dev.driver = NULL;
 577         udc->gadget->dev.driver = NULL;
 578         return ret;
 579 }
 580
 581 int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
 582 {
 583         struct usb_udc          *udc = NULL;
 584         int                     ret = -ENODEV;
 585
 586         if (!driver || !driver->bind || !driver->setup)
 587                 return -EINVAL;
 588
 589         mutex_lock(&udc_lock);
 590         if (driver->udc_name) {
 591                 list_for_each_entry(udc, &udc_list, list) {
 592                         ret = strcmp(driver->udc_name, dev_name(&udc->dev));
 593                         if (!ret)
 594                                 break;
 595                 }
 596                 if (!ret && !udc->driver)
 597                         goto found;
 598         } else {
 599                 list_for_each_entry(udc, &udc_list, list) {
 600                         /* For now we take the first one */
 601                         if (!udc->driver)
 602                                 goto found;
 603                 }
 604         }
 605
 606         if (!driver->match_existing_only) {
 607                 list_add_tail(&driver->pending, &gadget_driver_pending_list);
 608                 pr_info("udc-core: couldn't find an available UDC - added [%s] to list of pending drivers\n",
 609                         driver->function);
 610                 ret = 0;
 611         }
 612
 613         mutex_unlock(&udc_lock);
 614         return ret;
 615 found:
 616         ret = udc_bind_to_driver(udc, driver);
 617         mutex_unlock(&udc_lock);
 618         return ret;
 619 }
 620 EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);
 621
 622 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
 623 {
 624         struct usb_udc          *udc = NULL;
 625         int                     ret = -ENODEV;
 626
 627         if (!driver || !driver->unbind)
 628                 return -EINVAL;
 629
 630         mutex_lock(&udc_lock);
 631         list_for_each_entry(udc, &udc_list, list)
 632                 if (udc->driver == driver) {
 633                         usb_gadget_remove_driver(udc);
 634                         usb_gadget_set_state(udc->gadget,
 635                                         USB_STATE_NOTATTACHED);
 636                         ret = 0;
 637                         break;
 638                 }
 639
 640         if (ret) {
 641                 list_del(&driver->pending);
 642                 ret = 0;
 643         }
 644         mutex_unlock(&udc_lock);
 645         return ret;
 646 }
 647 EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
 648
 649 /* ------------------------------------------------------------------------- */
 650
 651 static ssize_t usb_udc_srp_store(struct device *dev,
 652                 struct device_attribute *attr, const char *buf, size_t n)
 653 {
 654         struct usb_udc          *udc = container_of(dev, struct usb_udc, dev);
 655
 656         if (sysfs_streq(buf, "1"))
 657                 usb_gadget_wakeup(udc->gadget);
 658
 659         return n;
 660 }
 661 static DEVICE_ATTR(srp, S_IWUSR, NULL, usb_udc_srp_store);
 662
 663 static ssize_t usb_udc_softconn_store(struct device *dev,
 664                 struct device_attribute *attr, const char *buf, size_t n)
 665 {
 666         struct usb_udc          *udc = container_of(dev, struct usb_udc, dev);
 667
 668         if (!udc->driver) {
 669                 dev_err(dev, "soft-connect without a gadget driver\n");
 670                 return -EOPNOTSUPP;
 671         }
 672
 673         if (sysfs_streq(buf, "connect")) {
 674                 usb_gadget_udc_start(udc);
 675                 usb_gadget_connect(udc->gadget);
 676         } else if (sysfs_streq(buf, "disconnect")) {
 677                 usb_gadget_disconnect(udc->gadget);
 678                 udc->driver->disconnect(udc->gadget);
 679                 usb_gadget_udc_stop(udc);
 680         } else {
 681                 dev_err(dev, "unsupported command '%s'\n", buf);
 682                 return -EINVAL;
 683         }
 684
 685         return n;
 686 }
 687 static DEVICE_ATTR(soft_connect, S_IWUSR, NULL, usb_udc_softconn_store);
 688
 689 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 690                           char *buf)
 691 {
 692         struct usb_udc          *udc = container_of(dev, struct usb_udc, dev);
 693         struct usb_gadget       *gadget = udc->gadget;
 694
 695         return sprintf(buf, "%s\n", usb_state_string(gadget->state));
 696 }
 697 static DEVICE_ATTR_RO(state);
 698
 699 #define USB_UDC_SPEED_ATTR(name, param)                                 \
 700 ssize_t name##_show(struct device *dev,                                 \
 701                 struct device_attribute *attr, char *buf)               \
 702 {                                                                       \
 703         struct usb_udc *udc = container_of(dev, struct usb_udc, dev);   \
 704         return snprintf(buf, PAGE_SIZE, "%s\n",                         \
 705                         usb_speed_string(udc->gadget->param));          \
 706 }                                                                       \
 707 static DEVICE_ATTR_RO(name)
 708
 709 static USB_UDC_SPEED_ATTR(current_speed, speed);
 710 static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
 711
 712 #define USB_UDC_ATTR(name)                                      \
 713 ssize_t name##_show(struct device *dev,                         \
 714                 struct device_attribute *attr, char *buf)       \
 715 {                                                               \
 716         struct usb_udc          *udc = container_of(dev, struct usb_udc, dev); \
 717         struct usb_gadget       *gadget = udc->gadget;          \
 718                                                                 \
 719         return snprintf(buf, PAGE_SIZE, "%d\n", gadget->name);  \
 720 }                                                               \
 721 static DEVICE_ATTR_RO(name)
 722
 723 static USB_UDC_ATTR(is_otg);
 724 static USB_UDC_ATTR(is_a_peripheral);
 725 static USB_UDC_ATTR(b_hnp_enable);
 726 static USB_UDC_ATTR(a_hnp_support);
 727 static USB_UDC_ATTR(a_alt_hnp_support);
 728 static USB_UDC_ATTR(is_selfpowered);
 729
 730 static struct attribute *usb_udc_attrs[] = {
 731         &dev_attr_srp.attr,
 732         &dev_attr_soft_connect.attr,
 733         &dev_attr_state.attr,
 734         &dev_attr_current_speed.attr,
 735         &dev_attr_maximum_speed.attr,
 736
 737         &dev_attr_is_otg.attr,
 738         &dev_attr_is_a_peripheral.attr,
 739         &dev_attr_b_hnp_enable.attr,
 740         &dev_attr_a_hnp_support.attr,
 741         &dev_attr_a_alt_hnp_support.attr,
 742         &dev_attr_is_selfpowered.attr,
 743         NULL,
 744 };
 745
 746 static const struct attribute_group usb_udc_attr_group = {
 747         .attrs = usb_udc_attrs,
 748 };
 749
 750 static const struct attribute_group *usb_udc_attr_groups[] = {
 751         &usb_udc_attr_group,
 752         NULL,
 753 };
 754
 755 static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env)
 756 {
 757         struct usb_udc          *udc = container_of(dev, struct usb_udc, dev);
 758         int                     ret;
 759
 760         ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
 761         if (ret) {
 762                 dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
 763                 return ret;
 764         }
 765
 766         if (udc->driver) {
 767                 ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
 768                                 udc->driver->function);
 769                 if (ret) {
 770                         dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
 771                         return ret;
 772                 }
 773         }
 774
 775         return 0;
 776 }
 777
 778 static int __init usb_udc_init(void)
 779 {
 780         udc_class = class_create(THIS_MODULE, "udc");
 781         if (IS_ERR(udc_class)) {
 782                 pr_err("failed to create udc class --> %ld\n",
 783                                 PTR_ERR(udc_class));
 784                 return PTR_ERR(udc_class);
 785         }
 786
 787         udc_class->dev_uevent = usb_udc_uevent;
 788         return 0;
 789 }
 790 subsys_initcall(usb_udc_init);
 791
 792 static void __exit usb_udc_exit(void)
 793 {
 794         class_destroy(udc_class);
 795 }
 796 module_exit(usb_udc_exit);
 797
 798 MODULE_DESCRIPTION("UDC Framework");
 799 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
 800 MODULE_LICENSE("GPL v2");