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