Merge tag 'usb-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
[sfrench/cifs-2.6.git] / 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(hub->intfdev);
55         int port1 = port_dev->portnum;
56         u16 portstatus, unused;
57         bool disabled;
58         int rc;
59
60         rc = usb_autopm_get_interface(intf);
61         if (rc < 0)
62                 return rc;
63
64         usb_lock_device(hdev);
65         if (hub->disconnected) {
66                 rc = -ENODEV;
67                 goto out_hdev_lock;
68         }
69
70         usb_hub_port_status(hub, port1, &portstatus, &unused);
71         disabled = !usb_port_is_power_on(hub, portstatus);
72
73 out_hdev_lock:
74         usb_unlock_device(hdev);
75         usb_autopm_put_interface(intf);
76
77         if (rc)
78                 return rc;
79
80         return sysfs_emit(buf, "%s\n", disabled ? "1" : "0");
81 }
82
83 static ssize_t disable_store(struct device *dev, struct device_attribute *attr,
84                             const char *buf, size_t count)
85 {
86         struct usb_port *port_dev = to_usb_port(dev);
87         struct usb_device *hdev = to_usb_device(dev->parent->parent);
88         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
89         struct usb_interface *intf = to_usb_interface(hub->intfdev);
90         int port1 = port_dev->portnum;
91         bool disabled;
92         int rc;
93
94         rc = kstrtobool(buf, &disabled);
95         if (rc)
96                 return rc;
97
98         rc = usb_autopm_get_interface(intf);
99         if (rc < 0)
100                 return rc;
101
102         usb_lock_device(hdev);
103         if (hub->disconnected) {
104                 rc = -ENODEV;
105                 goto out_hdev_lock;
106         }
107
108         if (disabled && port_dev->child)
109                 usb_disconnect(&port_dev->child);
110
111         rc = usb_hub_set_port_power(hdev, hub, port1, !disabled);
112
113         if (disabled) {
114                 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
115                 if (!port_dev->is_superspeed)
116                         usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
117         }
118
119         if (!rc)
120                 rc = count;
121
122 out_hdev_lock:
123         usb_unlock_device(hdev);
124         usb_autopm_put_interface(intf);
125
126         return rc;
127 }
128 static DEVICE_ATTR_RW(disable);
129
130 static ssize_t location_show(struct device *dev,
131                              struct device_attribute *attr, char *buf)
132 {
133         struct usb_port *port_dev = to_usb_port(dev);
134
135         return sprintf(buf, "0x%08x\n", port_dev->location);
136 }
137 static DEVICE_ATTR_RO(location);
138
139 static ssize_t connect_type_show(struct device *dev,
140                                  struct device_attribute *attr, char *buf)
141 {
142         struct usb_port *port_dev = to_usb_port(dev);
143         char *result;
144
145         switch (port_dev->connect_type) {
146         case USB_PORT_CONNECT_TYPE_HOT_PLUG:
147                 result = "hotplug";
148                 break;
149         case USB_PORT_CONNECT_TYPE_HARD_WIRED:
150                 result = "hardwired";
151                 break;
152         case USB_PORT_NOT_USED:
153                 result = "not used";
154                 break;
155         default:
156                 result = "unknown";
157                 break;
158         }
159
160         return sprintf(buf, "%s\n", result);
161 }
162 static DEVICE_ATTR_RO(connect_type);
163
164 static ssize_t state_show(struct device *dev,
165                           struct device_attribute *attr, char *buf)
166 {
167         struct usb_port *port_dev = to_usb_port(dev);
168         enum usb_device_state state = READ_ONCE(port_dev->state);
169
170         return sysfs_emit(buf, "%s\n", usb_state_string(state));
171 }
172 static DEVICE_ATTR_RO(state);
173
174 static ssize_t over_current_count_show(struct device *dev,
175                                        struct device_attribute *attr, char *buf)
176 {
177         struct usb_port *port_dev = to_usb_port(dev);
178
179         return sprintf(buf, "%u\n", port_dev->over_current_count);
180 }
181 static DEVICE_ATTR_RO(over_current_count);
182
183 static ssize_t quirks_show(struct device *dev,
184                            struct device_attribute *attr, char *buf)
185 {
186         struct usb_port *port_dev = to_usb_port(dev);
187
188         return sprintf(buf, "%08x\n", port_dev->quirks);
189 }
190
191 static ssize_t quirks_store(struct device *dev, struct device_attribute *attr,
192                             const char *buf, size_t count)
193 {
194         struct usb_port *port_dev = to_usb_port(dev);
195         u32 value;
196
197         if (kstrtou32(buf, 16, &value))
198                 return -EINVAL;
199
200         port_dev->quirks = value;
201         return count;
202 }
203 static DEVICE_ATTR_RW(quirks);
204
205 static ssize_t usb3_lpm_permit_show(struct device *dev,
206                               struct device_attribute *attr, char *buf)
207 {
208         struct usb_port *port_dev = to_usb_port(dev);
209         const char *p;
210
211         if (port_dev->usb3_lpm_u1_permit) {
212                 if (port_dev->usb3_lpm_u2_permit)
213                         p = "u1_u2";
214                 else
215                         p = "u1";
216         } else {
217                 if (port_dev->usb3_lpm_u2_permit)
218                         p = "u2";
219                 else
220                         p = "0";
221         }
222
223         return sprintf(buf, "%s\n", p);
224 }
225
226 static ssize_t usb3_lpm_permit_store(struct device *dev,
227                                struct device_attribute *attr,
228                                const char *buf, size_t count)
229 {
230         struct usb_port *port_dev = to_usb_port(dev);
231         struct usb_device *udev = port_dev->child;
232         struct usb_hcd *hcd;
233
234         if (!strncmp(buf, "u1_u2", 5)) {
235                 port_dev->usb3_lpm_u1_permit = 1;
236                 port_dev->usb3_lpm_u2_permit = 1;
237
238         } else if (!strncmp(buf, "u1", 2)) {
239                 port_dev->usb3_lpm_u1_permit = 1;
240                 port_dev->usb3_lpm_u2_permit = 0;
241
242         } else if (!strncmp(buf, "u2", 2)) {
243                 port_dev->usb3_lpm_u1_permit = 0;
244                 port_dev->usb3_lpm_u2_permit = 1;
245
246         } else if (!strncmp(buf, "0", 1)) {
247                 port_dev->usb3_lpm_u1_permit = 0;
248                 port_dev->usb3_lpm_u2_permit = 0;
249         } else
250                 return -EINVAL;
251
252         /* If device is connected to the port, disable or enable lpm
253          * to make new u1 u2 setting take effect immediately.
254          */
255         if (udev) {
256                 hcd = bus_to_hcd(udev->bus);
257                 if (!hcd)
258                         return -EINVAL;
259                 usb_lock_device(udev);
260                 mutex_lock(hcd->bandwidth_mutex);
261                 if (!usb_disable_lpm(udev))
262                         usb_enable_lpm(udev);
263                 mutex_unlock(hcd->bandwidth_mutex);
264                 usb_unlock_device(udev);
265         }
266
267         return count;
268 }
269 static DEVICE_ATTR_RW(usb3_lpm_permit);
270
271 static struct attribute *port_dev_attrs[] = {
272         &dev_attr_connect_type.attr,
273         &dev_attr_state.attr,
274         &dev_attr_location.attr,
275         &dev_attr_quirks.attr,
276         &dev_attr_over_current_count.attr,
277         &dev_attr_disable.attr,
278         &dev_attr_early_stop.attr,
279         NULL,
280 };
281
282 static const struct attribute_group port_dev_attr_grp = {
283         .attrs = port_dev_attrs,
284 };
285
286 static const struct attribute_group *port_dev_group[] = {
287         &port_dev_attr_grp,
288         NULL,
289 };
290
291 static struct attribute *port_dev_usb3_attrs[] = {
292         &dev_attr_usb3_lpm_permit.attr,
293         NULL,
294 };
295
296 static const struct attribute_group port_dev_usb3_attr_grp = {
297         .attrs = port_dev_usb3_attrs,
298 };
299
300 static const struct attribute_group *port_dev_usb3_group[] = {
301         &port_dev_attr_grp,
302         &port_dev_usb3_attr_grp,
303         NULL,
304 };
305
306 static void usb_port_device_release(struct device *dev)
307 {
308         struct usb_port *port_dev = to_usb_port(dev);
309
310         kfree(port_dev->req);
311         kfree(port_dev);
312 }
313
314 #ifdef CONFIG_PM
315 static int usb_port_runtime_resume(struct device *dev)
316 {
317         struct usb_port *port_dev = to_usb_port(dev);
318         struct usb_device *hdev = to_usb_device(dev->parent->parent);
319         struct usb_interface *intf = to_usb_interface(dev->parent);
320         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
321         struct usb_device *udev = port_dev->child;
322         struct usb_port *peer = port_dev->peer;
323         int port1 = port_dev->portnum;
324         int retval;
325
326         if (!hub)
327                 return -EINVAL;
328         if (hub->in_reset) {
329                 set_bit(port1, hub->power_bits);
330                 return 0;
331         }
332
333         /*
334          * Power on our usb3 peer before this usb2 port to prevent a usb3
335          * device from degrading to its usb2 connection
336          */
337         if (!port_dev->is_superspeed && peer)
338                 pm_runtime_get_sync(&peer->dev);
339
340         retval = usb_autopm_get_interface(intf);
341         if (retval < 0)
342                 return retval;
343
344         retval = usb_hub_set_port_power(hdev, hub, port1, true);
345         msleep(hub_power_on_good_delay(hub));
346         if (udev && !retval) {
347                 /*
348                  * Our preference is to simply wait for the port to reconnect,
349                  * as that is the lowest latency method to restart the port.
350                  * However, there are cases where toggling port power results in
351                  * the host port and the device port getting out of sync causing
352                  * a link training live lock.  Upon timeout, flag the port as
353                  * needing warm reset recovery (to be performed later by
354                  * usb_port_resume() as requested via usb_wakeup_notification())
355                  */
356                 if (hub_port_debounce_be_connected(hub, port1) < 0) {
357                         dev_dbg(&port_dev->dev, "reconnect timeout\n");
358                         if (hub_is_superspeed(hdev))
359                                 set_bit(port1, hub->warm_reset_bits);
360                 }
361
362                 /* Force the child awake to revalidate after the power loss. */
363                 if (!test_and_set_bit(port1, hub->child_usage_bits)) {
364                         pm_runtime_get_noresume(&port_dev->dev);
365                         pm_request_resume(&udev->dev);
366                 }
367         }
368
369         usb_autopm_put_interface(intf);
370
371         return retval;
372 }
373
374 static int usb_port_runtime_suspend(struct device *dev)
375 {
376         struct usb_port *port_dev = to_usb_port(dev);
377         struct usb_device *hdev = to_usb_device(dev->parent->parent);
378         struct usb_interface *intf = to_usb_interface(dev->parent);
379         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
380         struct usb_port *peer = port_dev->peer;
381         int port1 = port_dev->portnum;
382         int retval;
383
384         if (!hub)
385                 return -EINVAL;
386         if (hub->in_reset)
387                 return -EBUSY;
388
389         if (dev_pm_qos_flags(&port_dev->dev, PM_QOS_FLAG_NO_POWER_OFF)
390                         == PM_QOS_FLAGS_ALL)
391                 return -EAGAIN;
392
393         if (usb_port_block_power_off)
394                 return -EBUSY;
395
396         retval = usb_autopm_get_interface(intf);
397         if (retval < 0)
398                 return retval;
399
400         retval = usb_hub_set_port_power(hdev, hub, port1, false);
401         usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
402         if (!port_dev->is_superspeed)
403                 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
404         usb_autopm_put_interface(intf);
405
406         /*
407          * Our peer usb3 port may now be able to suspend, so
408          * asynchronously queue a suspend request to observe that this
409          * usb2 port is now off.
410          */
411         if (!port_dev->is_superspeed && peer)
412                 pm_runtime_put(&peer->dev);
413
414         return retval;
415 }
416 #endif
417
418 static void usb_port_shutdown(struct device *dev)
419 {
420         struct usb_port *port_dev = to_usb_port(dev);
421
422         if (port_dev->child)
423                 usb_disable_usb2_hardware_lpm(port_dev->child);
424 }
425
426 static const struct dev_pm_ops usb_port_pm_ops = {
427 #ifdef CONFIG_PM
428         .runtime_suspend =      usb_port_runtime_suspend,
429         .runtime_resume =       usb_port_runtime_resume,
430 #endif
431 };
432
433 const struct device_type usb_port_device_type = {
434         .name =         "usb_port",
435         .release =      usb_port_device_release,
436         .pm =           &usb_port_pm_ops,
437 };
438
439 static struct device_driver usb_port_driver = {
440         .name = "usb",
441         .owner = THIS_MODULE,
442         .shutdown = usb_port_shutdown,
443 };
444
445 static int link_peers(struct usb_port *left, struct usb_port *right)
446 {
447         struct usb_port *ss_port, *hs_port;
448         int rc;
449
450         if (left->peer == right && right->peer == left)
451                 return 0;
452
453         if (left->peer || right->peer) {
454                 struct usb_port *lpeer = left->peer;
455                 struct usb_port *rpeer = right->peer;
456                 char *method;
457
458                 if (left->location && left->location == right->location)
459                         method = "location";
460                 else
461                         method = "default";
462
463                 pr_debug("usb: failed to peer %s and %s by %s (%s:%s) (%s:%s)\n",
464                         dev_name(&left->dev), dev_name(&right->dev), method,
465                         dev_name(&left->dev),
466                         lpeer ? dev_name(&lpeer->dev) : "none",
467                         dev_name(&right->dev),
468                         rpeer ? dev_name(&rpeer->dev) : "none");
469                 return -EBUSY;
470         }
471
472         rc = sysfs_create_link(&left->dev.kobj, &right->dev.kobj, "peer");
473         if (rc)
474                 return rc;
475         rc = sysfs_create_link(&right->dev.kobj, &left->dev.kobj, "peer");
476         if (rc) {
477                 sysfs_remove_link(&left->dev.kobj, "peer");
478                 return rc;
479         }
480
481         /*
482          * We need to wake the HiSpeed port to make sure we don't race
483          * setting ->peer with usb_port_runtime_suspend().  Otherwise we
484          * may miss a suspend event for the SuperSpeed port.
485          */
486         if (left->is_superspeed) {
487                 ss_port = left;
488                 WARN_ON(right->is_superspeed);
489                 hs_port = right;
490         } else {
491                 ss_port = right;
492                 WARN_ON(!right->is_superspeed);
493                 hs_port = left;
494         }
495         pm_runtime_get_sync(&hs_port->dev);
496
497         left->peer = right;
498         right->peer = left;
499
500         /*
501          * The SuperSpeed reference is dropped when the HiSpeed port in
502          * this relationship suspends, i.e. when it is safe to allow a
503          * SuperSpeed connection to drop since there is no risk of a
504          * device degrading to its powered-off HiSpeed connection.
505          *
506          * Also, drop the HiSpeed ref taken above.
507          */
508         pm_runtime_get_sync(&ss_port->dev);
509         pm_runtime_put(&hs_port->dev);
510
511         return 0;
512 }
513
514 static void link_peers_report(struct usb_port *left, struct usb_port *right)
515 {
516         int rc;
517
518         rc = link_peers(left, right);
519         if (rc == 0) {
520                 dev_dbg(&left->dev, "peered to %s\n", dev_name(&right->dev));
521         } else {
522                 dev_dbg(&left->dev, "failed to peer to %s (%d)\n",
523                                 dev_name(&right->dev), rc);
524                 pr_warn_once("usb: port power management may be unreliable\n");
525                 usb_port_block_power_off = 1;
526         }
527 }
528
529 static void unlink_peers(struct usb_port *left, struct usb_port *right)
530 {
531         struct usb_port *ss_port, *hs_port;
532
533         WARN(right->peer != left || left->peer != right,
534                         "%s and %s are not peers?\n",
535                         dev_name(&left->dev), dev_name(&right->dev));
536
537         /*
538          * We wake the HiSpeed port to make sure we don't race its
539          * usb_port_runtime_resume() event which takes a SuperSpeed ref
540          * when ->peer is !NULL.
541          */
542         if (left->is_superspeed) {
543                 ss_port = left;
544                 hs_port = right;
545         } else {
546                 ss_port = right;
547                 hs_port = left;
548         }
549
550         pm_runtime_get_sync(&hs_port->dev);
551
552         sysfs_remove_link(&left->dev.kobj, "peer");
553         right->peer = NULL;
554         sysfs_remove_link(&right->dev.kobj, "peer");
555         left->peer = NULL;
556
557         /* Drop the SuperSpeed ref held on behalf of the active HiSpeed port */
558         pm_runtime_put(&ss_port->dev);
559
560         /* Drop the ref taken above */
561         pm_runtime_put(&hs_port->dev);
562 }
563
564 /*
565  * For each usb hub device in the system check to see if it is in the
566  * peer domain of the given port_dev, and if it is check to see if it
567  * has a port that matches the given port by location
568  */
569 static int match_location(struct usb_device *peer_hdev, void *p)
570 {
571         int port1;
572         struct usb_hcd *hcd, *peer_hcd;
573         struct usb_port *port_dev = p, *peer;
574         struct usb_hub *peer_hub = usb_hub_to_struct_hub(peer_hdev);
575         struct usb_device *hdev = to_usb_device(port_dev->dev.parent->parent);
576
577         if (!peer_hub || port_dev->connect_type == USB_PORT_NOT_USED)
578                 return 0;
579
580         hcd = bus_to_hcd(hdev->bus);
581         peer_hcd = bus_to_hcd(peer_hdev->bus);
582         /* peer_hcd is provisional until we verify it against the known peer */
583         if (peer_hcd != hcd->shared_hcd)
584                 return 0;
585
586         for (port1 = 1; port1 <= peer_hdev->maxchild; port1++) {
587                 peer = peer_hub->ports[port1 - 1];
588                 if (peer && peer->connect_type != USB_PORT_NOT_USED &&
589                     peer->location == port_dev->location) {
590                         link_peers_report(port_dev, peer);
591                         return 1; /* done */
592                 }
593         }
594
595         return 0;
596 }
597
598 /*
599  * Find the peer port either via explicit platform firmware "location"
600  * data, the peer hcd for root hubs, or the upstream peer relationship
601  * for all other hubs.
602  */
603 static void find_and_link_peer(struct usb_hub *hub, int port1)
604 {
605         struct usb_port *port_dev = hub->ports[port1 - 1], *peer;
606         struct usb_device *hdev = hub->hdev;
607         struct usb_device *peer_hdev;
608         struct usb_hub *peer_hub;
609
610         /*
611          * If location data is available then we can only peer this port
612          * by a location match, not the default peer (lest we create a
613          * situation where we need to go back and undo a default peering
614          * when the port is later peered by location data)
615          */
616         if (port_dev->location) {
617                 /* we link the peer in match_location() if found */
618                 usb_for_each_dev(port_dev, match_location);
619                 return;
620         } else if (!hdev->parent) {
621                 struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
622                 struct usb_hcd *peer_hcd = hcd->shared_hcd;
623
624                 if (!peer_hcd)
625                         return;
626
627                 peer_hdev = peer_hcd->self.root_hub;
628         } else {
629                 struct usb_port *upstream;
630                 struct usb_device *parent = hdev->parent;
631                 struct usb_hub *parent_hub = usb_hub_to_struct_hub(parent);
632
633                 if (!parent_hub)
634                         return;
635
636                 upstream = parent_hub->ports[hdev->portnum - 1];
637                 if (!upstream || !upstream->peer)
638                         return;
639
640                 peer_hdev = upstream->peer->child;
641         }
642
643         peer_hub = usb_hub_to_struct_hub(peer_hdev);
644         if (!peer_hub || port1 > peer_hdev->maxchild)
645                 return;
646
647         /*
648          * we found a valid default peer, last check is to make sure it
649          * does not have location data
650          */
651         peer = peer_hub->ports[port1 - 1];
652         if (peer && peer->location == 0)
653                 link_peers_report(port_dev, peer);
654 }
655
656 static int connector_bind(struct device *dev, struct device *connector, void *data)
657 {
658         struct usb_port *port_dev = to_usb_port(dev);
659         int ret;
660
661         ret = sysfs_create_link(&dev->kobj, &connector->kobj, "connector");
662         if (ret)
663                 return ret;
664
665         ret = sysfs_create_link(&connector->kobj, &dev->kobj, dev_name(dev));
666         if (ret) {
667                 sysfs_remove_link(&dev->kobj, "connector");
668                 return ret;
669         }
670
671         port_dev->connector = data;
672
673         /*
674          * If there is already USB device connected to the port, letting the
675          * Type-C connector know about it immediately.
676          */
677         if (port_dev->child)
678                 typec_attach(port_dev->connector, &port_dev->child->dev);
679
680         return 0;
681 }
682
683 static void connector_unbind(struct device *dev, struct device *connector, void *data)
684 {
685         struct usb_port *port_dev = to_usb_port(dev);
686
687         sysfs_remove_link(&connector->kobj, dev_name(dev));
688         sysfs_remove_link(&dev->kobj, "connector");
689         port_dev->connector = NULL;
690 }
691
692 static const struct component_ops connector_ops = {
693         .bind = connector_bind,
694         .unbind = connector_unbind,
695 };
696
697 int usb_hub_create_port_device(struct usb_hub *hub, int port1)
698 {
699         struct usb_port *port_dev;
700         struct usb_device *hdev = hub->hdev;
701         int retval;
702
703         port_dev = kzalloc(sizeof(*port_dev), GFP_KERNEL);
704         if (!port_dev)
705                 return -ENOMEM;
706
707         port_dev->req = kzalloc(sizeof(*(port_dev->req)), GFP_KERNEL);
708         if (!port_dev->req) {
709                 kfree(port_dev);
710                 return -ENOMEM;
711         }
712
713         port_dev->connect_type = usb_of_get_connect_type(hdev, port1);
714         hub->ports[port1 - 1] = port_dev;
715         port_dev->portnum = port1;
716         set_bit(port1, hub->power_bits);
717         port_dev->dev.parent = hub->intfdev;
718         if (hub_is_superspeed(hdev)) {
719                 port_dev->is_superspeed = 1;
720                 port_dev->usb3_lpm_u1_permit = 1;
721                 port_dev->usb3_lpm_u2_permit = 1;
722                 port_dev->dev.groups = port_dev_usb3_group;
723         } else
724                 port_dev->dev.groups = port_dev_group;
725         port_dev->dev.type = &usb_port_device_type;
726         port_dev->dev.driver = &usb_port_driver;
727         dev_set_name(&port_dev->dev, "%s-port%d", dev_name(&hub->hdev->dev),
728                         port1);
729         mutex_init(&port_dev->status_lock);
730         retval = device_register(&port_dev->dev);
731         if (retval) {
732                 put_device(&port_dev->dev);
733                 return retval;
734         }
735
736         port_dev->state_kn = sysfs_get_dirent(port_dev->dev.kobj.sd, "state");
737         if (!port_dev->state_kn) {
738                 dev_err(&port_dev->dev, "failed to sysfs_get_dirent 'state'\n");
739                 retval = -ENODEV;
740                 goto err_unregister;
741         }
742
743         /* Set default policy of port-poweroff disabled. */
744         retval = dev_pm_qos_add_request(&port_dev->dev, port_dev->req,
745                         DEV_PM_QOS_FLAGS, PM_QOS_FLAG_NO_POWER_OFF);
746         if (retval < 0) {
747                 goto err_put_kn;
748         }
749
750         retval = component_add(&port_dev->dev, &connector_ops);
751         if (retval) {
752                 dev_warn(&port_dev->dev, "failed to add component\n");
753                 goto err_put_kn;
754         }
755
756         find_and_link_peer(hub, port1);
757
758         /*
759          * Enable runtime pm and hold a refernce that hub_configure()
760          * will drop once the PM_QOS_NO_POWER_OFF flag state has been set
761          * and the hub has been fully registered (hdev->maxchild set).
762          */
763         pm_runtime_set_active(&port_dev->dev);
764         pm_runtime_get_noresume(&port_dev->dev);
765         pm_runtime_enable(&port_dev->dev);
766         device_enable_async_suspend(&port_dev->dev);
767
768         /*
769          * Keep hidden the ability to enable port-poweroff if the hub
770          * does not support power switching.
771          */
772         if (!hub_is_port_power_switchable(hub))
773                 return 0;
774
775         /* Attempt to let userspace take over the policy. */
776         retval = dev_pm_qos_expose_flags(&port_dev->dev,
777                         PM_QOS_FLAG_NO_POWER_OFF);
778         if (retval < 0) {
779                 dev_warn(&port_dev->dev, "failed to expose pm_qos_no_poweroff\n");
780                 return 0;
781         }
782
783         /* Userspace owns the policy, drop the kernel 'no_poweroff' request. */
784         retval = dev_pm_qos_remove_request(port_dev->req);
785         if (retval >= 0) {
786                 kfree(port_dev->req);
787                 port_dev->req = NULL;
788         }
789         return 0;
790
791 err_put_kn:
792         sysfs_put(port_dev->state_kn);
793 err_unregister:
794         device_unregister(&port_dev->dev);
795
796         return retval;
797 }
798
799 void usb_hub_remove_port_device(struct usb_hub *hub, int port1)
800 {
801         struct usb_port *port_dev = hub->ports[port1 - 1];
802         struct usb_port *peer;
803
804         peer = port_dev->peer;
805         if (peer)
806                 unlink_peers(port_dev, peer);
807         component_del(&port_dev->dev, &connector_ops);
808         sysfs_put(port_dev->state_kn);
809         device_unregister(&port_dev->dev);
810 }