drivers/usb/core/port.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * usb port device code
   4  *
   5  * Copyright (C) 2012 Intel Corp
   6  *
   7  * Author: Lan Tianyu <tianyu.lan@intel.com>
   8  */
   9
  10 #include <linux/kstrtox.h>
  11 #include <linux/slab.h>
  12 #include <linux/pm_qos.h>
  13 #include <linux/component.h>
  14 #include <linux/usb/of.h>
  15
  16 #include "hub.h"
  17
  18 static int usb_port_block_power_off;
  19
  20 static const struct attribute_group *port_dev_group[];
  21
  22 static ssize_t early_stop_show(struct device *dev,
  23                             struct device_attribute *attr, char *buf)
  24 {
  25         struct usb_port *port_dev = to_usb_port(dev);
  26
  27         return sysfs_emit(buf, "%s\n", port_dev->early_stop ? "yes" : "no");
  28 }
  29
  30 static ssize_t early_stop_store(struct device *dev, struct device_attribute *attr,
  31                                 const char *buf, size_t count)
  32 {
  33         struct usb_port *port_dev = to_usb_port(dev);
  34         bool value;
  35
  36         if (kstrtobool(buf, &value))
  37                 return -EINVAL;
  38
  39         if (value)
  40                 port_dev->early_stop = 1;
  41         else
  42                 port_dev->early_stop = 0;
  43
  44         return count;
  45 }
  46 static DEVICE_ATTR_RW(early_stop);
  47
  48 static ssize_t disable_show(struct device *dev,
  49                               struct device_attribute *attr, char *buf)
  50 {
  51         struct usb_port *port_dev = to_usb_port(dev);
  52         struct usb_device *hdev = to_usb_device(dev->parent->parent);
  53         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
  54         struct usb_interface *intf = to_usb_interface(dev->parent);
  55         int port1 = port_dev->portnum;
  56         u16 portstatus, unused;
  57         bool disabled;
  58         int rc;
  59         struct kernfs_node *kn;
  60
  61         if (!hub)
  62                 return -ENODEV;
  63         hub_get(hub);
  64         rc = usb_autopm_get_interface(intf);
  65         if (rc < 0)
  66                 goto out_hub_get;
  67
  68         /*
  69          * Prevent deadlock if another process is concurrently
  70          * trying to unregister hdev.
  71          */
  72         kn = sysfs_break_active_protection(&dev->kobj, &attr->attr);
  73         if (!kn) {
  74                 rc = -ENODEV;
  75                 goto out_autopm;
  76         }
  77         usb_lock_device(hdev);
  78         if (hub->disconnected) {
  79                 rc = -ENODEV;
  80                 goto out_hdev_lock;
  81         }
  82
  83         usb_hub_port_status(hub, port1, &portstatus, &unused);
  84         disabled = !usb_port_is_power_on(hub, portstatus);
  85
  86  out_hdev_lock:
  87         usb_unlock_device(hdev);
  88         sysfs_unbreak_active_protection(kn);
  89  out_autopm:
  90         usb_autopm_put_interface(intf);
  91  out_hub_get:
  92         hub_put(hub);
  93
  94         if (rc)
  95                 return rc;
  96
  97         return sysfs_emit(buf, "%s\n", disabled ? "1" : "0");
  98 }
  99
 100 static ssize_t disable_store(struct device *dev, struct device_attribute *attr,
 101                             const char *buf, size_t count)
 102 {
 103         struct usb_port *port_dev = to_usb_port(dev);
 104         struct usb_device *hdev = to_usb_device(dev->parent->parent);
 105         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 106         struct usb_interface *intf = to_usb_interface(dev->parent);
 107         int port1 = port_dev->portnum;
 108         bool disabled;
 109         int rc;
 110         struct kernfs_node *kn;
 111
 112         if (!hub)
 113                 return -ENODEV;
 114         rc = kstrtobool(buf, &disabled);
 115         if (rc)
 116                 return rc;
 117
 118         hub_get(hub);
 119         rc = usb_autopm_get_interface(intf);
 120         if (rc < 0)
 121                 goto out_hub_get;
 122
 123         /*
 124          * Prevent deadlock if another process is concurrently
 125          * trying to unregister hdev.
 126          */
 127         kn = sysfs_break_active_protection(&dev->kobj, &attr->attr);
 128         if (!kn) {
 129                 rc = -ENODEV;
 130                 goto out_autopm;
 131         }
 132         usb_lock_device(hdev);
 133         if (hub->disconnected) {
 134                 rc = -ENODEV;
 135                 goto out_hdev_lock;
 136         }
 137
 138         if (disabled && port_dev->child)
 139                 usb_disconnect(&port_dev->child);
 140
 141         rc = usb_hub_set_port_power(hdev, hub, port1, !disabled);
 142
 143         if (disabled) {
 144                 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
 145                 if (!port_dev->is_superspeed)
 146                         usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
 147         }
 148
 149         if (!rc)
 150                 rc = count;
 151
 152  out_hdev_lock:
 153         usb_unlock_device(hdev);
 154         sysfs_unbreak_active_protection(kn);
 155  out_autopm:
 156         usb_autopm_put_interface(intf);
 157  out_hub_get:
 158         hub_put(hub);
 159
 160         return rc;
 161 }
 162 static DEVICE_ATTR_RW(disable);
 163
 164 static ssize_t location_show(struct device *dev,
 165                              struct device_attribute *attr, char *buf)
 166 {
 167         struct usb_port *port_dev = to_usb_port(dev);
 168
 169         return sprintf(buf, "0x%08x\n", port_dev->location);
 170 }
 171 static DEVICE_ATTR_RO(location);
 172
 173 static ssize_t connect_type_show(struct device *dev,
 174                                  struct device_attribute *attr, char *buf)
 175 {
 176         struct usb_port *port_dev = to_usb_port(dev);
 177         char *result;
 178
 179         switch (port_dev->connect_type) {
 180         case USB_PORT_CONNECT_TYPE_HOT_PLUG:
 181                 result = "hotplug";
 182                 break;
 183         case USB_PORT_CONNECT_TYPE_HARD_WIRED:
 184                 result = "hardwired";
 185                 break;
 186         case USB_PORT_NOT_USED:
 187                 result = "not used";
 188                 break;
 189         default:
 190                 result = "unknown";
 191                 break;
 192         }
 193
 194         return sprintf(buf, "%s\n", result);
 195 }
 196 static DEVICE_ATTR_RO(connect_type);
 197
 198 static ssize_t state_show(struct device *dev,
 199                           struct device_attribute *attr, char *buf)
 200 {
 201         struct usb_port *port_dev = to_usb_port(dev);
 202         enum usb_device_state state = READ_ONCE(port_dev->state);
 203
 204         return sysfs_emit(buf, "%s\n", usb_state_string(state));
 205 }
 206 static DEVICE_ATTR_RO(state);
 207
 208 static ssize_t over_current_count_show(struct device *dev,
 209                                        struct device_attribute *attr, char *buf)
 210 {
 211         struct usb_port *port_dev = to_usb_port(dev);
 212
 213         return sprintf(buf, "%u\n", port_dev->over_current_count);
 214 }
 215 static DEVICE_ATTR_RO(over_current_count);
 216
 217 static ssize_t quirks_show(struct device *dev,
 218                            struct device_attribute *attr, char *buf)
 219 {
 220         struct usb_port *port_dev = to_usb_port(dev);
 221
 222         return sprintf(buf, "%08x\n", port_dev->quirks);
 223 }
 224
 225 static ssize_t quirks_store(struct device *dev, struct device_attribute *attr,
 226                             const char *buf, size_t count)
 227 {
 228         struct usb_port *port_dev = to_usb_port(dev);
 229         u32 value;
 230
 231         if (kstrtou32(buf, 16, &value))
 232                 return -EINVAL;
 233
 234         port_dev->quirks = value;
 235         return count;
 236 }
 237 static DEVICE_ATTR_RW(quirks);
 238
 239 static ssize_t usb3_lpm_permit_show(struct device *dev,
 240                               struct device_attribute *attr, char *buf)
 241 {
 242         struct usb_port *port_dev = to_usb_port(dev);
 243         const char *p;
 244
 245         if (port_dev->usb3_lpm_u1_permit) {
 246                 if (port_dev->usb3_lpm_u2_permit)
 247                         p = "u1_u2";
 248                 else
 249                         p = "u1";
 250         } else {
 251                 if (port_dev->usb3_lpm_u2_permit)
 252                         p = "u2";
 253                 else
 254                         p = "0";
 255         }
 256
 257         return sprintf(buf, "%s\n", p);
 258 }
 259
 260 static ssize_t usb3_lpm_permit_store(struct device *dev,
 261                                struct device_attribute *attr,
 262                                const char *buf, size_t count)
 263 {
 264         struct usb_port *port_dev = to_usb_port(dev);
 265         struct usb_device *udev = port_dev->child;
 266         struct usb_hcd *hcd;
 267
 268         if (!strncmp(buf, "u1_u2", 5)) {
 269                 port_dev->usb3_lpm_u1_permit = 1;
 270                 port_dev->usb3_lpm_u2_permit = 1;
 271
 272         } else if (!strncmp(buf, "u1", 2)) {
 273                 port_dev->usb3_lpm_u1_permit = 1;
 274                 port_dev->usb3_lpm_u2_permit = 0;
 275
 276         } else if (!strncmp(buf, "u2", 2)) {
 277                 port_dev->usb3_lpm_u1_permit = 0;
 278                 port_dev->usb3_lpm_u2_permit = 1;
 279
 280         } else if (!strncmp(buf, "0", 1)) {
 281                 port_dev->usb3_lpm_u1_permit = 0;
 282                 port_dev->usb3_lpm_u2_permit = 0;
 283         } else
 284                 return -EINVAL;
 285
 286         /* If device is connected to the port, disable or enable lpm
 287          * to make new u1 u2 setting take effect immediately.
 288          */
 289         if (udev) {
 290                 hcd = bus_to_hcd(udev->bus);
 291                 if (!hcd)
 292                         return -EINVAL;
 293                 usb_lock_device(udev);
 294                 mutex_lock(hcd->bandwidth_mutex);
 295                 if (!usb_disable_lpm(udev))
 296                         usb_enable_lpm(udev);
 297                 mutex_unlock(hcd->bandwidth_mutex);
 298                 usb_unlock_device(udev);
 299         }
 300
 301         return count;
 302 }
 303 static DEVICE_ATTR_RW(usb3_lpm_permit);
 304
 305 static struct attribute *port_dev_attrs[] = {
 306         &dev_attr_connect_type.attr,
 307         &dev_attr_state.attr,
 308         &dev_attr_location.attr,
 309         &dev_attr_quirks.attr,
 310         &dev_attr_over_current_count.attr,
 311         &dev_attr_disable.attr,
 312         &dev_attr_early_stop.attr,
 313         NULL,
 314 };
 315
 316 static const struct attribute_group port_dev_attr_grp = {
 317         .attrs = port_dev_attrs,
 318 };
 319
 320 static const struct attribute_group *port_dev_group[] = {
 321         &port_dev_attr_grp,
 322         NULL,
 323 };
 324
 325 static struct attribute *port_dev_usb3_attrs[] = {
 326         &dev_attr_usb3_lpm_permit.attr,
 327         NULL,
 328 };
 329
 330 static const struct attribute_group port_dev_usb3_attr_grp = {
 331         .attrs = port_dev_usb3_attrs,
 332 };
 333
 334 static const struct attribute_group *port_dev_usb3_group[] = {
 335         &port_dev_attr_grp,
 336         &port_dev_usb3_attr_grp,
 337         NULL,
 338 };
 339
 340 static void usb_port_device_release(struct device *dev)
 341 {
 342         struct usb_port *port_dev = to_usb_port(dev);
 343
 344         kfree(port_dev->req);
 345         kfree(port_dev);
 346 }
 347
 348 #ifdef CONFIG_PM
 349 static int usb_port_runtime_resume(struct device *dev)
 350 {
 351         struct usb_port *port_dev = to_usb_port(dev);
 352         struct usb_device *hdev = to_usb_device(dev->parent->parent);
 353         struct usb_interface *intf = to_usb_interface(dev->parent);
 354         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 355         struct usb_device *udev = port_dev->child;
 356         struct usb_port *peer = port_dev->peer;
 357         int port1 = port_dev->portnum;
 358         int retval;
 359
 360         if (!hub)
 361                 return -EINVAL;
 362         if (hub->in_reset) {
 363                 set_bit(port1, hub->power_bits);
 364                 return 0;
 365         }
 366
 367         /*
 368          * Power on our usb3 peer before this usb2 port to prevent a usb3
 369          * device from degrading to its usb2 connection
 370          */
 371         if (!port_dev->is_superspeed && peer)
 372                 pm_runtime_get_sync(&peer->dev);
 373
 374         retval = usb_autopm_get_interface(intf);
 375         if (retval < 0)
 376                 return retval;
 377
 378         retval = usb_hub_set_port_power(hdev, hub, port1, true);
 379         msleep(hub_power_on_good_delay(hub));
 380         if (udev && !retval) {
 381                 /*
 382                  * Our preference is to simply wait for the port to reconnect,
 383                  * as that is the lowest latency method to restart the port.
 384                  * However, there are cases where toggling port power results in
 385                  * the host port and the device port getting out of sync causing
 386                  * a link training live lock.  Upon timeout, flag the port as
 387                  * needing warm reset recovery (to be performed later by
 388                  * usb_port_resume() as requested via usb_wakeup_notification())
 389                  */
 390                 if (hub_port_debounce_be_connected(hub, port1) < 0) {
 391                         dev_dbg(&port_dev->dev, "reconnect timeout\n");
 392                         if (hub_is_superspeed(hdev))
 393                                 set_bit(port1, hub->warm_reset_bits);
 394                 }
 395
 396                 /* Force the child awake to revalidate after the power loss. */
 397                 if (!test_and_set_bit(port1, hub->child_usage_bits)) {
 398                         pm_runtime_get_noresume(&port_dev->dev);
 399                         pm_request_resume(&udev->dev);
 400                 }
 401         }
 402
 403         usb_autopm_put_interface(intf);
 404
 405         return retval;
 406 }
 407
 408 static int usb_port_runtime_suspend(struct device *dev)
 409 {
 410         struct usb_port *port_dev = to_usb_port(dev);
 411         struct usb_device *hdev = to_usb_device(dev->parent->parent);
 412         struct usb_interface *intf = to_usb_interface(dev->parent);
 413         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 414         struct usb_port *peer = port_dev->peer;
 415         int port1 = port_dev->portnum;
 416         int retval;
 417
 418         if (!hub)
 419                 return -EINVAL;
 420         if (hub->in_reset)
 421                 return -EBUSY;
 422
 423         if (dev_pm_qos_flags(&port_dev->dev, PM_QOS_FLAG_NO_POWER_OFF)
 424                         == PM_QOS_FLAGS_ALL)
 425                 return -EAGAIN;
 426
 427         if (usb_port_block_power_off)
 428                 return -EBUSY;
 429
 430         retval = usb_autopm_get_interface(intf);
 431         if (retval < 0)
 432                 return retval;
 433
 434         retval = usb_hub_set_port_power(hdev, hub, port1, false);
 435         usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
 436         if (!port_dev->is_superspeed)
 437                 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
 438         usb_autopm_put_interface(intf);
 439
 440         /*
 441          * Our peer usb3 port may now be able to suspend, so
 442          * asynchronously queue a suspend request to observe that this
 443          * usb2 port is now off.
 444          */
 445         if (!port_dev->is_superspeed && peer)
 446                 pm_runtime_put(&peer->dev);
 447
 448         return retval;
 449 }
 450 #endif
 451
 452 static void usb_port_shutdown(struct device *dev)
 453 {
 454         struct usb_port *port_dev = to_usb_port(dev);
 455
 456         if (port_dev->child) {
 457                 usb_disable_usb2_hardware_lpm(port_dev->child);
 458                 usb_unlocked_disable_lpm(port_dev->child);
 459         }
 460 }
 461
 462 static const struct dev_pm_ops usb_port_pm_ops = {
 463 #ifdef CONFIG_PM
 464         .runtime_suspend =      usb_port_runtime_suspend,
 465         .runtime_resume =       usb_port_runtime_resume,
 466 #endif
 467 };
 468
 469 const struct device_type usb_port_device_type = {
 470         .name =         "usb_port",
 471         .release =      usb_port_device_release,
 472         .pm =           &usb_port_pm_ops,
 473 };
 474
 475 static struct device_driver usb_port_driver = {
 476         .name = "usb",
 477         .owner = THIS_MODULE,
 478         .shutdown = usb_port_shutdown,
 479 };
 480
 481 static int link_peers(struct usb_port *left, struct usb_port *right)
 482 {
 483         struct usb_port *ss_port, *hs_port;
 484         int rc;
 485
 486         if (left->peer == right && right->peer == left)
 487                 return 0;
 488
 489         if (left->peer || right->peer) {
 490                 struct usb_port *lpeer = left->peer;
 491                 struct usb_port *rpeer = right->peer;
 492                 char *method;
 493
 494                 if (left->location && left->location == right->location)
 495                         method = "location";
 496                 else
 497                         method = "default";
 498
 499                 pr_debug("usb: failed to peer %s and %s by %s (%s:%s) (%s:%s)\n",
 500                         dev_name(&left->dev), dev_name(&right->dev), method,
 501                         dev_name(&left->dev),
 502                         lpeer ? dev_name(&lpeer->dev) : "none",
 503                         dev_name(&right->dev),
 504                         rpeer ? dev_name(&rpeer->dev) : "none");
 505                 return -EBUSY;
 506         }
 507
 508         rc = sysfs_create_link(&left->dev.kobj, &right->dev.kobj, "peer");
 509         if (rc)
 510                 return rc;
 511         rc = sysfs_create_link(&right->dev.kobj, &left->dev.kobj, "peer");
 512         if (rc) {
 513                 sysfs_remove_link(&left->dev.kobj, "peer");
 514                 return rc;
 515         }
 516
 517         /*
 518          * We need to wake the HiSpeed port to make sure we don't race
 519          * setting ->peer with usb_port_runtime_suspend().  Otherwise we
 520          * may miss a suspend event for the SuperSpeed port.
 521          */
 522         if (left->is_superspeed) {
 523                 ss_port = left;
 524                 WARN_ON(right->is_superspeed);
 525                 hs_port = right;
 526         } else {
 527                 ss_port = right;
 528                 WARN_ON(!right->is_superspeed);
 529                 hs_port = left;
 530         }
 531         pm_runtime_get_sync(&hs_port->dev);
 532
 533         left->peer = right;
 534         right->peer = left;
 535
 536         /*
 537          * The SuperSpeed reference is dropped when the HiSpeed port in
 538          * this relationship suspends, i.e. when it is safe to allow a
 539          * SuperSpeed connection to drop since there is no risk of a
 540          * device degrading to its powered-off HiSpeed connection.
 541          *
 542          * Also, drop the HiSpeed ref taken above.
 543          */
 544         pm_runtime_get_sync(&ss_port->dev);
 545         pm_runtime_put(&hs_port->dev);
 546
 547         return 0;
 548 }
 549
 550 static void link_peers_report(struct usb_port *left, struct usb_port *right)
 551 {
 552         int rc;
 553
 554         rc = link_peers(left, right);
 555         if (rc == 0) {
 556                 dev_dbg(&left->dev, "peered to %s\n", dev_name(&right->dev));
 557         } else {
 558                 dev_dbg(&left->dev, "failed to peer to %s (%d)\n",
 559                                 dev_name(&right->dev), rc);
 560                 pr_warn_once("usb: port power management may be unreliable\n");
 561                 usb_port_block_power_off = 1;
 562         }
 563 }
 564
 565 static void unlink_peers(struct usb_port *left, struct usb_port *right)
 566 {
 567         struct usb_port *ss_port, *hs_port;
 568
 569         WARN(right->peer != left || left->peer != right,
 570                         "%s and %s are not peers?\n",
 571                         dev_name(&left->dev), dev_name(&right->dev));
 572
 573         /*
 574          * We wake the HiSpeed port to make sure we don't race its
 575          * usb_port_runtime_resume() event which takes a SuperSpeed ref
 576          * when ->peer is !NULL.
 577          */
 578         if (left->is_superspeed) {
 579                 ss_port = left;
 580                 hs_port = right;
 581         } else {
 582                 ss_port = right;
 583                 hs_port = left;
 584         }
 585
 586         pm_runtime_get_sync(&hs_port->dev);
 587
 588         sysfs_remove_link(&left->dev.kobj, "peer");
 589         right->peer = NULL;
 590         sysfs_remove_link(&right->dev.kobj, "peer");
 591         left->peer = NULL;
 592
 593         /* Drop the SuperSpeed ref held on behalf of the active HiSpeed port */
 594         pm_runtime_put(&ss_port->dev);
 595
 596         /* Drop the ref taken above */
 597         pm_runtime_put(&hs_port->dev);
 598 }
 599
 600 /*
 601  * For each usb hub device in the system check to see if it is in the
 602  * peer domain of the given port_dev, and if it is check to see if it
 603  * has a port that matches the given port by location
 604  */
 605 static int match_location(struct usb_device *peer_hdev, void *p)
 606 {
 607         int port1;
 608         struct usb_hcd *hcd, *peer_hcd;
 609         struct usb_port *port_dev = p, *peer;
 610         struct usb_hub *peer_hub = usb_hub_to_struct_hub(peer_hdev);
 611         struct usb_device *hdev = to_usb_device(port_dev->dev.parent->parent);
 612
 613         if (!peer_hub || port_dev->connect_type == USB_PORT_NOT_USED)
 614                 return 0;
 615
 616         hcd = bus_to_hcd(hdev->bus);
 617         peer_hcd = bus_to_hcd(peer_hdev->bus);
 618         /* peer_hcd is provisional until we verify it against the known peer */
 619         if (peer_hcd != hcd->shared_hcd)
 620                 return 0;
 621
 622         for (port1 = 1; port1 <= peer_hdev->maxchild; port1++) {
 623                 peer = peer_hub->ports[port1 - 1];
 624                 if (peer && peer->connect_type != USB_PORT_NOT_USED &&
 625                     peer->location == port_dev->location) {
 626                         link_peers_report(port_dev, peer);
 627                         return 1; /* done */
 628                 }
 629         }
 630
 631         return 0;
 632 }
 633
 634 /*
 635  * Find the peer port either via explicit platform firmware "location"
 636  * data, the peer hcd for root hubs, or the upstream peer relationship
 637  * for all other hubs.
 638  */
 639 static void find_and_link_peer(struct usb_hub *hub, int port1)
 640 {
 641         struct usb_port *port_dev = hub->ports[port1 - 1], *peer;
 642         struct usb_device *hdev = hub->hdev;
 643         struct usb_device *peer_hdev;
 644         struct usb_hub *peer_hub;
 645
 646         /*
 647          * If location data is available then we can only peer this port
 648          * by a location match, not the default peer (lest we create a
 649          * situation where we need to go back and undo a default peering
 650          * when the port is later peered by location data)
 651          */
 652         if (port_dev->location) {
 653                 /* we link the peer in match_location() if found */
 654                 usb_for_each_dev(port_dev, match_location);
 655                 return;
 656         } else if (!hdev->parent) {
 657                 struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
 658                 struct usb_hcd *peer_hcd = hcd->shared_hcd;
 659
 660                 if (!peer_hcd)
 661                         return;
 662
 663                 peer_hdev = peer_hcd->self.root_hub;
 664         } else {
 665                 struct usb_port *upstream;
 666                 struct usb_device *parent = hdev->parent;
 667                 struct usb_hub *parent_hub = usb_hub_to_struct_hub(parent);
 668
 669                 if (!parent_hub)
 670                         return;
 671
 672                 upstream = parent_hub->ports[hdev->portnum - 1];
 673                 if (!upstream || !upstream->peer)
 674                         return;
 675
 676                 peer_hdev = upstream->peer->child;
 677         }
 678
 679         peer_hub = usb_hub_to_struct_hub(peer_hdev);
 680         if (!peer_hub || port1 > peer_hdev->maxchild)
 681                 return;
 682
 683         /*
 684          * we found a valid default peer, last check is to make sure it
 685          * does not have location data
 686          */
 687         peer = peer_hub->ports[port1 - 1];
 688         if (peer && peer->location == 0)
 689                 link_peers_report(port_dev, peer);
 690 }
 691
 692 static int connector_bind(struct device *dev, struct device *connector, void *data)
 693 {
 694         struct usb_port *port_dev = to_usb_port(dev);
 695         int ret;
 696
 697         ret = sysfs_create_link(&dev->kobj, &connector->kobj, "connector");
 698         if (ret)
 699                 return ret;
 700
 701         ret = sysfs_create_link(&connector->kobj, &dev->kobj, dev_name(dev));
 702         if (ret) {
 703                 sysfs_remove_link(&dev->kobj, "connector");
 704                 return ret;
 705         }
 706
 707         port_dev->connector = data;
 708
 709         /*
 710          * If there is already USB device connected to the port, letting the
 711          * Type-C connector know about it immediately.
 712          */
 713         if (port_dev->child)
 714                 typec_attach(port_dev->connector, &port_dev->child->dev);
 715
 716         return 0;
 717 }
 718
 719 static void connector_unbind(struct device *dev, struct device *connector, void *data)
 720 {
 721         struct usb_port *port_dev = to_usb_port(dev);
 722
 723         sysfs_remove_link(&connector->kobj, dev_name(dev));
 724         sysfs_remove_link(&dev->kobj, "connector");
 725         port_dev->connector = NULL;
 726 }
 727
 728 static const struct component_ops connector_ops = {
 729         .bind = connector_bind,
 730         .unbind = connector_unbind,
 731 };
 732
 733 int usb_hub_create_port_device(struct usb_hub *hub, int port1)
 734 {
 735         struct usb_port *port_dev;
 736         struct usb_device *hdev = hub->hdev;
 737         int retval;
 738
 739         port_dev = kzalloc(sizeof(*port_dev), GFP_KERNEL);
 740         if (!port_dev)
 741                 return -ENOMEM;
 742
 743         port_dev->req = kzalloc(sizeof(*(port_dev->req)), GFP_KERNEL);
 744         if (!port_dev->req) {
 745                 kfree(port_dev);
 746                 return -ENOMEM;
 747         }
 748
 749         port_dev->connect_type = usb_of_get_connect_type(hdev, port1);
 750         hub->ports[port1 - 1] = port_dev;
 751         port_dev->portnum = port1;
 752         set_bit(port1, hub->power_bits);
 753         port_dev->dev.parent = hub->intfdev;
 754         if (hub_is_superspeed(hdev)) {
 755                 port_dev->is_superspeed = 1;
 756                 port_dev->usb3_lpm_u1_permit = 1;
 757                 port_dev->usb3_lpm_u2_permit = 1;
 758                 port_dev->dev.groups = port_dev_usb3_group;
 759         } else
 760                 port_dev->dev.groups = port_dev_group;
 761         port_dev->dev.type = &usb_port_device_type;
 762         port_dev->dev.driver = &usb_port_driver;
 763         dev_set_name(&port_dev->dev, "%s-port%d", dev_name(&hub->hdev->dev),
 764                         port1);
 765         mutex_init(&port_dev->status_lock);
 766         retval = device_register(&port_dev->dev);
 767         if (retval) {
 768                 put_device(&port_dev->dev);
 769                 return retval;
 770         }
 771
 772         port_dev->state_kn = sysfs_get_dirent(port_dev->dev.kobj.sd, "state");
 773         if (!port_dev->state_kn) {
 774                 dev_err(&port_dev->dev, "failed to sysfs_get_dirent 'state'\n");
 775                 retval = -ENODEV;
 776                 goto err_unregister;
 777         }
 778
 779         /* Set default policy of port-poweroff disabled. */
 780         retval = dev_pm_qos_add_request(&port_dev->dev, port_dev->req,
 781                         DEV_PM_QOS_FLAGS, PM_QOS_FLAG_NO_POWER_OFF);
 782         if (retval < 0) {
 783                 goto err_put_kn;
 784         }
 785
 786         retval = component_add(&port_dev->dev, &connector_ops);
 787         if (retval) {
 788                 dev_warn(&port_dev->dev, "failed to add component\n");
 789                 goto err_put_kn;
 790         }
 791
 792         find_and_link_peer(hub, port1);
 793
 794         /*
 795          * Enable runtime pm and hold a refernce that hub_configure()
 796          * will drop once the PM_QOS_NO_POWER_OFF flag state has been set
 797          * and the hub has been fully registered (hdev->maxchild set).
 798          */
 799         pm_runtime_set_active(&port_dev->dev);
 800         pm_runtime_get_noresume(&port_dev->dev);
 801         pm_runtime_enable(&port_dev->dev);
 802         device_enable_async_suspend(&port_dev->dev);
 803
 804         /*
 805          * Keep hidden the ability to enable port-poweroff if the hub
 806          * does not support power switching.
 807          */
 808         if (!hub_is_port_power_switchable(hub))
 809                 return 0;
 810
 811         /* Attempt to let userspace take over the policy. */
 812         retval = dev_pm_qos_expose_flags(&port_dev->dev,
 813                         PM_QOS_FLAG_NO_POWER_OFF);
 814         if (retval < 0) {
 815                 dev_warn(&port_dev->dev, "failed to expose pm_qos_no_poweroff\n");
 816                 return 0;
 817         }
 818
 819         /* Userspace owns the policy, drop the kernel 'no_poweroff' request. */
 820         retval = dev_pm_qos_remove_request(port_dev->req);
 821         if (retval >= 0) {
 822                 kfree(port_dev->req);
 823                 port_dev->req = NULL;
 824         }
 825         return 0;
 826
 827 err_put_kn:
 828         sysfs_put(port_dev->state_kn);
 829 err_unregister:
 830         device_unregister(&port_dev->dev);
 831
 832         return retval;
 833 }
 834
 835 void usb_hub_remove_port_device(struct usb_hub *hub, int port1)
 836 {
 837         struct usb_port *port_dev = hub->ports[port1 - 1];
 838         struct usb_port *peer;
 839
 840         peer = port_dev->peer;
 841         if (peer)
 842                 unlink_peers(port_dev, peer);
 843         component_del(&port_dev->dev, &connector_ops);
 844         sysfs_put(port_dev->state_kn);
 845         device_unregister(&port_dev->dev);
 846 }