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

source code of linux/drivers/usb/core/port.c