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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, "%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(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}
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(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
100static 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}
162static DEVICE_ATTR_RW(disable);
163
164static 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}
171static DEVICE_ATTR_RO(location);
172
173static 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}
196static DEVICE_ATTR_RO(connect_type);
197
198static 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}
206static DEVICE_ATTR_RO(state);
207
208static 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}
215static DEVICE_ATTR_RO(over_current_count);
216
217static 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
225static 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}
237static DEVICE_ATTR_RW(quirks);
238
239static 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
260static 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}
303static DEVICE_ATTR_RW(usb3_lpm_permit);
304
305static 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
316static const struct attribute_group port_dev_attr_grp = {
317 .attrs = port_dev_attrs,
318};
319
320static const struct attribute_group *port_dev_group[] = {
321 &port_dev_attr_grp,
322 NULL,
323};
324
325static struct attribute *port_dev_usb3_attrs[] = {
326 &dev_attr_usb3_lpm_permit.attr,
327 NULL,
328};
329
330static const struct attribute_group port_dev_usb3_attr_grp = {
331 .attrs = port_dev_usb3_attrs,
332};
333
334static const struct attribute_group *port_dev_usb3_group[] = {
335 &port_dev_attr_grp,
336 &port_dev_usb3_attr_grp,
337 NULL,
338};
339
340static 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
349static 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
408static 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
452static 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
462static 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
469const 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
475static struct device_driver usb_port_driver = {
476 .name = "usb",
477 .owner = THIS_MODULE,
478 .shutdown = usb_port_shutdown,
479};
480
481static 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
550static 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
565static 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 */
605static 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 */
639static 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
692static 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
719static 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
728static const struct component_ops connector_ops = {
729 .bind = connector_bind,
730 .unbind = connector_unbind,
731};
732
733int 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
827err_put_kn:
828 sysfs_put(port_dev->state_kn);
829err_unregister:
830 device_unregister(&port_dev->dev);
831
832 return retval;
833}
834
835void 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}
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/sysfs.h>
13#include <linux/pm_qos.h>
14#include <linux/component.h>
15#include <linux/usb/of.h>
16
17#include "hub.h"
18
19static int usb_port_block_power_off;
20
21static const struct attribute_group *port_dev_group[];
22
23static ssize_t early_stop_show(struct device *dev,
24 struct device_attribute *attr, char *buf)
25{
26 struct usb_port *port_dev = to_usb_port(dev);
27
28 return sysfs_emit(buf, "%s\n", port_dev->early_stop ? "yes" : "no");
29}
30
31static ssize_t early_stop_store(struct device *dev, struct device_attribute *attr,
32 const char *buf, size_t count)
33{
34 struct usb_port *port_dev = to_usb_port(dev);
35 bool value;
36
37 if (kstrtobool(buf, &value))
38 return -EINVAL;
39
40 if (value)
41 port_dev->early_stop = 1;
42 else
43 port_dev->early_stop = 0;
44
45 return count;
46}
47static DEVICE_ATTR_RW(early_stop);
48
49static ssize_t disable_show(struct device *dev,
50 struct device_attribute *attr, char *buf)
51{
52 struct usb_port *port_dev = to_usb_port(dev);
53 struct usb_device *hdev = to_usb_device(dev->parent->parent);
54 struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
55 struct usb_interface *intf = to_usb_interface(dev->parent);
56 int port1 = port_dev->portnum;
57 u16 portstatus, unused;
58 bool disabled;
59 int rc;
60 struct kernfs_node *kn;
61
62 if (!hub)
63 return -ENODEV;
64 hub_get(hub);
65 rc = usb_autopm_get_interface(intf);
66 if (rc < 0)
67 goto out_hub_get;
68
69 /*
70 * Prevent deadlock if another process is concurrently
71 * trying to unregister hdev.
72 */
73 kn = sysfs_break_active_protection(&dev->kobj, &attr->attr);
74 if (!kn) {
75 rc = -ENODEV;
76 goto out_autopm;
77 }
78 usb_lock_device(hdev);
79 if (hub->disconnected) {
80 rc = -ENODEV;
81 goto out_hdev_lock;
82 }
83
84 usb_hub_port_status(hub, port1, &portstatus, &unused);
85 disabled = !usb_port_is_power_on(hub, portstatus);
86
87 out_hdev_lock:
88 usb_unlock_device(hdev);
89 sysfs_unbreak_active_protection(kn);
90 out_autopm:
91 usb_autopm_put_interface(intf);
92 out_hub_get:
93 hub_put(hub);
94
95 if (rc)
96 return rc;
97
98 return sysfs_emit(buf, "%s\n", disabled ? "1" : "0");
99}
100
101static ssize_t disable_store(struct device *dev, struct device_attribute *attr,
102 const char *buf, size_t count)
103{
104 struct usb_port *port_dev = to_usb_port(dev);
105 struct usb_device *hdev = to_usb_device(dev->parent->parent);
106 struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
107 struct usb_interface *intf = to_usb_interface(dev->parent);
108 int port1 = port_dev->portnum;
109 bool disabled;
110 int rc;
111 struct kernfs_node *kn;
112
113 if (!hub)
114 return -ENODEV;
115 rc = kstrtobool(buf, &disabled);
116 if (rc)
117 return rc;
118
119 hub_get(hub);
120 rc = usb_autopm_get_interface(intf);
121 if (rc < 0)
122 goto out_hub_get;
123
124 /*
125 * Prevent deadlock if another process is concurrently
126 * trying to unregister hdev.
127 */
128 kn = sysfs_break_active_protection(&dev->kobj, &attr->attr);
129 if (!kn) {
130 rc = -ENODEV;
131 goto out_autopm;
132 }
133 usb_lock_device(hdev);
134 if (hub->disconnected) {
135 rc = -ENODEV;
136 goto out_hdev_lock;
137 }
138
139 if (disabled && port_dev->child)
140 usb_disconnect(&port_dev->child);
141
142 rc = usb_hub_set_port_power(hdev, hub, port1, !disabled);
143
144 if (disabled) {
145 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
146 if (!port_dev->is_superspeed)
147 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
148 }
149
150 if (!rc)
151 rc = count;
152
153 out_hdev_lock:
154 usb_unlock_device(hdev);
155 sysfs_unbreak_active_protection(kn);
156 out_autopm:
157 usb_autopm_put_interface(intf);
158 out_hub_get:
159 hub_put(hub);
160
161 return rc;
162}
163static DEVICE_ATTR_RW(disable);
164
165static ssize_t location_show(struct device *dev,
166 struct device_attribute *attr, char *buf)
167{
168 struct usb_port *port_dev = to_usb_port(dev);
169
170 return sysfs_emit(buf, "0x%08x\n", port_dev->location);
171}
172static DEVICE_ATTR_RO(location);
173
174static ssize_t connect_type_show(struct device *dev,
175 struct device_attribute *attr, char *buf)
176{
177 struct usb_port *port_dev = to_usb_port(dev);
178 char *result;
179
180 switch (port_dev->connect_type) {
181 case USB_PORT_CONNECT_TYPE_HOT_PLUG:
182 result = "hotplug";
183 break;
184 case USB_PORT_CONNECT_TYPE_HARD_WIRED:
185 result = "hardwired";
186 break;
187 case USB_PORT_NOT_USED:
188 result = "not used";
189 break;
190 default:
191 result = "unknown";
192 break;
193 }
194
195 return sysfs_emit(buf, "%s\n", result);
196}
197static DEVICE_ATTR_RO(connect_type);
198
199static ssize_t state_show(struct device *dev,
200 struct device_attribute *attr, char *buf)
201{
202 struct usb_port *port_dev = to_usb_port(dev);
203 enum usb_device_state state = READ_ONCE(port_dev->state);
204
205 return sysfs_emit(buf, "%s\n", usb_state_string(state));
206}
207static DEVICE_ATTR_RO(state);
208
209static ssize_t over_current_count_show(struct device *dev,
210 struct device_attribute *attr, char *buf)
211{
212 struct usb_port *port_dev = to_usb_port(dev);
213
214 return sysfs_emit(buf, "%u\n", port_dev->over_current_count);
215}
216static DEVICE_ATTR_RO(over_current_count);
217
218static ssize_t quirks_show(struct device *dev,
219 struct device_attribute *attr, char *buf)
220{
221 struct usb_port *port_dev = to_usb_port(dev);
222
223 return sysfs_emit(buf, "%08x\n", port_dev->quirks);
224}
225
226static ssize_t quirks_store(struct device *dev, struct device_attribute *attr,
227 const char *buf, size_t count)
228{
229 struct usb_port *port_dev = to_usb_port(dev);
230 u32 value;
231
232 if (kstrtou32(buf, 16, &value))
233 return -EINVAL;
234
235 port_dev->quirks = value;
236 return count;
237}
238static DEVICE_ATTR_RW(quirks);
239
240static ssize_t usb3_lpm_permit_show(struct device *dev,
241 struct device_attribute *attr, char *buf)
242{
243 struct usb_port *port_dev = to_usb_port(dev);
244 const char *p;
245
246 if (port_dev->usb3_lpm_u1_permit) {
247 if (port_dev->usb3_lpm_u2_permit)
248 p = "u1_u2";
249 else
250 p = "u1";
251 } else {
252 if (port_dev->usb3_lpm_u2_permit)
253 p = "u2";
254 else
255 p = "0";
256 }
257
258 return sysfs_emit(buf, "%s\n", p);
259}
260
261static ssize_t usb3_lpm_permit_store(struct device *dev,
262 struct device_attribute *attr,
263 const char *buf, size_t count)
264{
265 struct usb_port *port_dev = to_usb_port(dev);
266 struct usb_device *udev = port_dev->child;
267 struct usb_hcd *hcd;
268
269 if (!strncmp(buf, "u1_u2", 5)) {
270 port_dev->usb3_lpm_u1_permit = 1;
271 port_dev->usb3_lpm_u2_permit = 1;
272
273 } else if (!strncmp(buf, "u1", 2)) {
274 port_dev->usb3_lpm_u1_permit = 1;
275 port_dev->usb3_lpm_u2_permit = 0;
276
277 } else if (!strncmp(buf, "u2", 2)) {
278 port_dev->usb3_lpm_u1_permit = 0;
279 port_dev->usb3_lpm_u2_permit = 1;
280
281 } else if (!strncmp(buf, "0", 1)) {
282 port_dev->usb3_lpm_u1_permit = 0;
283 port_dev->usb3_lpm_u2_permit = 0;
284 } else
285 return -EINVAL;
286
287 /* If device is connected to the port, disable or enable lpm
288 * to make new u1 u2 setting take effect immediately.
289 */
290 if (udev) {
291 hcd = bus_to_hcd(udev->bus);
292 if (!hcd)
293 return -EINVAL;
294 usb_lock_device(udev);
295 mutex_lock(hcd->bandwidth_mutex);
296 if (!usb_disable_lpm(udev))
297 usb_enable_lpm(udev);
298 mutex_unlock(hcd->bandwidth_mutex);
299 usb_unlock_device(udev);
300 }
301
302 return count;
303}
304static DEVICE_ATTR_RW(usb3_lpm_permit);
305
306static struct attribute *port_dev_attrs[] = {
307 &dev_attr_connect_type.attr,
308 &dev_attr_state.attr,
309 &dev_attr_location.attr,
310 &dev_attr_quirks.attr,
311 &dev_attr_over_current_count.attr,
312 &dev_attr_disable.attr,
313 &dev_attr_early_stop.attr,
314 NULL,
315};
316
317static const struct attribute_group port_dev_attr_grp = {
318 .attrs = port_dev_attrs,
319};
320
321static const struct attribute_group *port_dev_group[] = {
322 &port_dev_attr_grp,
323 NULL,
324};
325
326static struct attribute *port_dev_usb3_attrs[] = {
327 &dev_attr_usb3_lpm_permit.attr,
328 NULL,
329};
330
331static const struct attribute_group port_dev_usb3_attr_grp = {
332 .attrs = port_dev_usb3_attrs,
333};
334
335static const struct attribute_group *port_dev_usb3_group[] = {
336 &port_dev_attr_grp,
337 &port_dev_usb3_attr_grp,
338 NULL,
339};
340
341static void usb_port_device_release(struct device *dev)
342{
343 struct usb_port *port_dev = to_usb_port(dev);
344
345 kfree(port_dev->req);
346 kfree(port_dev);
347}
348
349#ifdef CONFIG_PM
350static int usb_port_runtime_resume(struct device *dev)
351{
352 struct usb_port *port_dev = to_usb_port(dev);
353 struct usb_device *hdev = to_usb_device(dev->parent->parent);
354 struct usb_interface *intf = to_usb_interface(dev->parent);
355 struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
356 struct usb_device *udev = port_dev->child;
357 struct usb_port *peer = port_dev->peer;
358 int port1 = port_dev->portnum;
359 int retval;
360
361 if (!hub)
362 return -EINVAL;
363 if (hub->in_reset) {
364 set_bit(port1, hub->power_bits);
365 return 0;
366 }
367
368 /*
369 * Power on our usb3 peer before this usb2 port to prevent a usb3
370 * device from degrading to its usb2 connection
371 */
372 if (!port_dev->is_superspeed && peer)
373 pm_runtime_get_sync(&peer->dev);
374
375 retval = usb_autopm_get_interface(intf);
376 if (retval < 0)
377 return retval;
378
379 retval = usb_hub_set_port_power(hdev, hub, port1, true);
380 msleep(hub_power_on_good_delay(hub));
381 if (udev && !retval) {
382 /*
383 * Our preference is to simply wait for the port to reconnect,
384 * as that is the lowest latency method to restart the port.
385 * However, there are cases where toggling port power results in
386 * the host port and the device port getting out of sync causing
387 * a link training live lock. Upon timeout, flag the port as
388 * needing warm reset recovery (to be performed later by
389 * usb_port_resume() as requested via usb_wakeup_notification())
390 */
391 if (hub_port_debounce_be_connected(hub, port1) < 0) {
392 dev_dbg(&port_dev->dev, "reconnect timeout\n");
393 if (hub_is_superspeed(hdev))
394 set_bit(port1, hub->warm_reset_bits);
395 }
396
397 /* Force the child awake to revalidate after the power loss. */
398 if (!test_and_set_bit(port1, hub->child_usage_bits)) {
399 pm_runtime_get_noresume(&port_dev->dev);
400 pm_request_resume(&udev->dev);
401 }
402 }
403
404 usb_autopm_put_interface(intf);
405
406 return retval;
407}
408
409static int usb_port_runtime_suspend(struct device *dev)
410{
411 struct usb_port *port_dev = to_usb_port(dev);
412 struct usb_device *hdev = to_usb_device(dev->parent->parent);
413 struct usb_interface *intf = to_usb_interface(dev->parent);
414 struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
415 struct usb_port *peer = port_dev->peer;
416 int port1 = port_dev->portnum;
417 int retval;
418
419 if (!hub)
420 return -EINVAL;
421 if (hub->in_reset)
422 return -EBUSY;
423
424 if (dev_pm_qos_flags(&port_dev->dev, PM_QOS_FLAG_NO_POWER_OFF)
425 == PM_QOS_FLAGS_ALL)
426 return -EAGAIN;
427
428 if (usb_port_block_power_off)
429 return -EBUSY;
430
431 retval = usb_autopm_get_interface(intf);
432 if (retval < 0)
433 return retval;
434
435 retval = usb_hub_set_port_power(hdev, hub, port1, false);
436 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
437 if (!port_dev->is_superspeed)
438 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
439 usb_autopm_put_interface(intf);
440
441 /*
442 * Our peer usb3 port may now be able to suspend, so
443 * asynchronously queue a suspend request to observe that this
444 * usb2 port is now off.
445 */
446 if (!port_dev->is_superspeed && peer)
447 pm_runtime_put(&peer->dev);
448
449 return retval;
450}
451#endif
452
453static void usb_port_shutdown(struct device *dev)
454{
455 struct usb_port *port_dev = to_usb_port(dev);
456 struct usb_device *udev = port_dev->child;
457
458 if (udev && !udev->port_is_suspended) {
459 usb_disable_usb2_hardware_lpm(udev);
460 usb_unlocked_disable_lpm(udev);
461 }
462}
463
464static const struct dev_pm_ops usb_port_pm_ops = {
465#ifdef CONFIG_PM
466 .runtime_suspend = usb_port_runtime_suspend,
467 .runtime_resume = usb_port_runtime_resume,
468#endif
469};
470
471const struct device_type usb_port_device_type = {
472 .name = "usb_port",
473 .release = usb_port_device_release,
474 .pm = &usb_port_pm_ops,
475};
476
477static struct device_driver usb_port_driver = {
478 .name = "usb",
479 .owner = THIS_MODULE,
480 .shutdown = usb_port_shutdown,
481};
482
483static int link_peers(struct usb_port *left, struct usb_port *right)
484{
485 struct usb_port *ss_port, *hs_port;
486 int rc;
487
488 if (left->peer == right && right->peer == left)
489 return 0;
490
491 if (left->peer || right->peer) {
492 struct usb_port *lpeer = left->peer;
493 struct usb_port *rpeer = right->peer;
494 char *method;
495
496 if (left->location && left->location == right->location)
497 method = "location";
498 else
499 method = "default";
500
501 pr_debug("usb: failed to peer %s and %s by %s (%s:%s) (%s:%s)\n",
502 dev_name(&left->dev), dev_name(&right->dev), method,
503 dev_name(&left->dev),
504 lpeer ? dev_name(&lpeer->dev) : "none",
505 dev_name(&right->dev),
506 rpeer ? dev_name(&rpeer->dev) : "none");
507 return -EBUSY;
508 }
509
510 rc = sysfs_create_link(&left->dev.kobj, &right->dev.kobj, "peer");
511 if (rc)
512 return rc;
513 rc = sysfs_create_link(&right->dev.kobj, &left->dev.kobj, "peer");
514 if (rc) {
515 sysfs_remove_link(&left->dev.kobj, "peer");
516 return rc;
517 }
518
519 /*
520 * We need to wake the HiSpeed port to make sure we don't race
521 * setting ->peer with usb_port_runtime_suspend(). Otherwise we
522 * may miss a suspend event for the SuperSpeed port.
523 */
524 if (left->is_superspeed) {
525 ss_port = left;
526 WARN_ON(right->is_superspeed);
527 hs_port = right;
528 } else {
529 ss_port = right;
530 WARN_ON(!right->is_superspeed);
531 hs_port = left;
532 }
533 pm_runtime_get_sync(&hs_port->dev);
534
535 left->peer = right;
536 right->peer = left;
537
538 /*
539 * The SuperSpeed reference is dropped when the HiSpeed port in
540 * this relationship suspends, i.e. when it is safe to allow a
541 * SuperSpeed connection to drop since there is no risk of a
542 * device degrading to its powered-off HiSpeed connection.
543 *
544 * Also, drop the HiSpeed ref taken above.
545 */
546 pm_runtime_get_sync(&ss_port->dev);
547 pm_runtime_put(&hs_port->dev);
548
549 return 0;
550}
551
552static void link_peers_report(struct usb_port *left, struct usb_port *right)
553{
554 int rc;
555
556 rc = link_peers(left, right);
557 if (rc == 0) {
558 dev_dbg(&left->dev, "peered to %s\n", dev_name(&right->dev));
559 } else {
560 dev_dbg(&left->dev, "failed to peer to %s (%d)\n",
561 dev_name(&right->dev), rc);
562 pr_warn_once("usb: port power management may be unreliable\n");
563 usb_port_block_power_off = 1;
564 }
565}
566
567static void unlink_peers(struct usb_port *left, struct usb_port *right)
568{
569 struct usb_port *ss_port, *hs_port;
570
571 WARN(right->peer != left || left->peer != right,
572 "%s and %s are not peers?\n",
573 dev_name(&left->dev), dev_name(&right->dev));
574
575 /*
576 * We wake the HiSpeed port to make sure we don't race its
577 * usb_port_runtime_resume() event which takes a SuperSpeed ref
578 * when ->peer is !NULL.
579 */
580 if (left->is_superspeed) {
581 ss_port = left;
582 hs_port = right;
583 } else {
584 ss_port = right;
585 hs_port = left;
586 }
587
588 pm_runtime_get_sync(&hs_port->dev);
589
590 sysfs_remove_link(&left->dev.kobj, "peer");
591 right->peer = NULL;
592 sysfs_remove_link(&right->dev.kobj, "peer");
593 left->peer = NULL;
594
595 /* Drop the SuperSpeed ref held on behalf of the active HiSpeed port */
596 pm_runtime_put(&ss_port->dev);
597
598 /* Drop the ref taken above */
599 pm_runtime_put(&hs_port->dev);
600}
601
602/*
603 * For each usb hub device in the system check to see if it is in the
604 * peer domain of the given port_dev, and if it is check to see if it
605 * has a port that matches the given port by location
606 */
607static int match_location(struct usb_device *peer_hdev, void *p)
608{
609 int port1;
610 struct usb_hcd *hcd, *peer_hcd;
611 struct usb_port *port_dev = p, *peer;
612 struct usb_hub *peer_hub = usb_hub_to_struct_hub(peer_hdev);
613 struct usb_device *hdev = to_usb_device(port_dev->dev.parent->parent);
614
615 if (!peer_hub || port_dev->connect_type == USB_PORT_NOT_USED)
616 return 0;
617
618 hcd = bus_to_hcd(hdev->bus);
619 peer_hcd = bus_to_hcd(peer_hdev->bus);
620 /* peer_hcd is provisional until we verify it against the known peer */
621 if (peer_hcd != hcd->shared_hcd)
622 return 0;
623
624 for (port1 = 1; port1 <= peer_hdev->maxchild; port1++) {
625 peer = peer_hub->ports[port1 - 1];
626 if (peer && peer->connect_type != USB_PORT_NOT_USED &&
627 peer->location == port_dev->location) {
628 link_peers_report(port_dev, peer);
629 return 1; /* done */
630 }
631 }
632
633 return 0;
634}
635
636/*
637 * Find the peer port either via explicit platform firmware "location"
638 * data, the peer hcd for root hubs, or the upstream peer relationship
639 * for all other hubs.
640 */
641static void find_and_link_peer(struct usb_hub *hub, int port1)
642{
643 struct usb_port *port_dev = hub->ports[port1 - 1], *peer;
644 struct usb_device *hdev = hub->hdev;
645 struct usb_device *peer_hdev;
646 struct usb_hub *peer_hub;
647
648 /*
649 * If location data is available then we can only peer this port
650 * by a location match, not the default peer (lest we create a
651 * situation where we need to go back and undo a default peering
652 * when the port is later peered by location data)
653 */
654 if (port_dev->location) {
655 /* we link the peer in match_location() if found */
656 usb_for_each_dev(port_dev, match_location);
657 return;
658 } else if (!hdev->parent) {
659 struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
660 struct usb_hcd *peer_hcd = hcd->shared_hcd;
661
662 if (!peer_hcd)
663 return;
664
665 peer_hdev = peer_hcd->self.root_hub;
666 } else {
667 struct usb_port *upstream;
668 struct usb_device *parent = hdev->parent;
669 struct usb_hub *parent_hub = usb_hub_to_struct_hub(parent);
670
671 if (!parent_hub)
672 return;
673
674 upstream = parent_hub->ports[hdev->portnum - 1];
675 if (!upstream || !upstream->peer)
676 return;
677
678 peer_hdev = upstream->peer->child;
679 }
680
681 peer_hub = usb_hub_to_struct_hub(peer_hdev);
682 if (!peer_hub || port1 > peer_hdev->maxchild)
683 return;
684
685 /*
686 * we found a valid default peer, last check is to make sure it
687 * does not have location data
688 */
689 peer = peer_hub->ports[port1 - 1];
690 if (peer && peer->location == 0)
691 link_peers_report(port_dev, peer);
692}
693
694static int connector_bind(struct device *dev, struct device *connector, void *data)
695{
696 struct usb_port *port_dev = to_usb_port(dev);
697 int ret;
698
699 ret = sysfs_create_link(&dev->kobj, &connector->kobj, "connector");
700 if (ret)
701 return ret;
702
703 ret = sysfs_create_link(&connector->kobj, &dev->kobj, dev_name(dev));
704 if (ret) {
705 sysfs_remove_link(&dev->kobj, "connector");
706 return ret;
707 }
708
709 port_dev->connector = data;
710
711 /*
712 * If there is already USB device connected to the port, letting the
713 * Type-C connector know about it immediately.
714 */
715 if (port_dev->child)
716 typec_attach(port_dev->connector, &port_dev->child->dev);
717
718 return 0;
719}
720
721static void connector_unbind(struct device *dev, struct device *connector, void *data)
722{
723 struct usb_port *port_dev = to_usb_port(dev);
724
725 sysfs_remove_link(&connector->kobj, dev_name(dev));
726 sysfs_remove_link(&dev->kobj, "connector");
727 port_dev->connector = NULL;
728}
729
730static const struct component_ops connector_ops = {
731 .bind = connector_bind,
732 .unbind = connector_unbind,
733};
734
735int usb_hub_create_port_device(struct usb_hub *hub, int port1)
736{
737 struct usb_port *port_dev;
738 struct usb_device *hdev = hub->hdev;
739 int retval;
740
741 port_dev = kzalloc(sizeof(*port_dev), GFP_KERNEL);
742 if (!port_dev)
743 return -ENOMEM;
744
745 port_dev->req = kzalloc(sizeof(*(port_dev->req)), GFP_KERNEL);
746 if (!port_dev->req) {
747 kfree(port_dev);
748 return -ENOMEM;
749 }
750
751 port_dev->connect_type = usb_of_get_connect_type(hdev, port1);
752 hub->ports[port1 - 1] = port_dev;
753 port_dev->portnum = port1;
754 set_bit(port1, hub->power_bits);
755 port_dev->dev.parent = hub->intfdev;
756 if (hub_is_superspeed(hdev)) {
757 port_dev->is_superspeed = 1;
758 port_dev->usb3_lpm_u1_permit = 1;
759 port_dev->usb3_lpm_u2_permit = 1;
760 port_dev->dev.groups = port_dev_usb3_group;
761 } else
762 port_dev->dev.groups = port_dev_group;
763 port_dev->dev.type = &usb_port_device_type;
764 port_dev->dev.driver = &usb_port_driver;
765 dev_set_name(&port_dev->dev, "%s-port%d", dev_name(&hub->hdev->dev),
766 port1);
767 mutex_init(&port_dev->status_lock);
768 retval = device_register(&port_dev->dev);
769 if (retval) {
770 put_device(&port_dev->dev);
771 return retval;
772 }
773
774 port_dev->state_kn = sysfs_get_dirent(port_dev->dev.kobj.sd, "state");
775 if (!port_dev->state_kn) {
776 dev_err(&port_dev->dev, "failed to sysfs_get_dirent 'state'\n");
777 retval = -ENODEV;
778 goto err_unregister;
779 }
780
781 /* Set default policy of port-poweroff disabled. */
782 retval = dev_pm_qos_add_request(&port_dev->dev, port_dev->req,
783 DEV_PM_QOS_FLAGS, PM_QOS_FLAG_NO_POWER_OFF);
784 if (retval < 0) {
785 goto err_put_kn;
786 }
787
788 retval = component_add(&port_dev->dev, &connector_ops);
789 if (retval) {
790 dev_warn(&port_dev->dev, "failed to add component\n");
791 goto err_put_kn;
792 }
793
794 find_and_link_peer(hub, port1);
795
796 /*
797 * Enable runtime pm and hold a refernce that hub_configure()
798 * will drop once the PM_QOS_NO_POWER_OFF flag state has been set
799 * and the hub has been fully registered (hdev->maxchild set).
800 */
801 pm_runtime_set_active(&port_dev->dev);
802 pm_runtime_get_noresume(&port_dev->dev);
803 pm_runtime_enable(&port_dev->dev);
804 device_enable_async_suspend(&port_dev->dev);
805
806 /*
807 * Keep hidden the ability to enable port-poweroff if the hub
808 * does not support power switching.
809 */
810 if (!hub_is_port_power_switchable(hub))
811 return 0;
812
813 /* Attempt to let userspace take over the policy. */
814 retval = dev_pm_qos_expose_flags(&port_dev->dev,
815 PM_QOS_FLAG_NO_POWER_OFF);
816 if (retval < 0) {
817 dev_warn(&port_dev->dev, "failed to expose pm_qos_no_poweroff\n");
818 return 0;
819 }
820
821 /* Userspace owns the policy, drop the kernel 'no_poweroff' request. */
822 retval = dev_pm_qos_remove_request(port_dev->req);
823 if (retval >= 0) {
824 kfree(port_dev->req);
825 port_dev->req = NULL;
826 }
827 return 0;
828
829err_put_kn:
830 sysfs_put(port_dev->state_kn);
831err_unregister:
832 device_unregister(&port_dev->dev);
833
834 return retval;
835}
836
837void usb_hub_remove_port_device(struct usb_hub *hub, int port1)
838{
839 struct usb_port *port_dev = hub->ports[port1 - 1];
840 struct usb_port *peer;
841
842 peer = port_dev->peer;
843 if (peer)
844 unlink_peers(port_dev, peer);
845 component_del(&port_dev->dev, &connector_ops);
846 sysfs_put(port_dev->state_kn);
847 device_unregister(&port_dev->dev);
848}