1 // SPDX-License-Identifier: GPL-2.0
5 * Copyright (C) 2012 Intel Corp
10 #include <linux/kstrtox.h>
11 #include <linux/slab.h>
12 #include <linux/pm_qos.h>
13 #include <linux/component.h>
17 static int usb_port_block_power_off;
19 static const struct attribute_group *port_dev_group[];
21 static ssize_t early_stop_show(struct device *dev,
22 struct device_attribute *attr, char *buf)
24 struct usb_port *port_dev = to_usb_port(dev);
26 return sysfs_emit(buf, "%s\n", port_dev->early_stop ? "yes" : "no");
29 static ssize_t early_stop_store(struct device *dev, struct device_attribute *attr,
30 const char *buf, size_t count)
32 struct usb_port *port_dev = to_usb_port(dev);
35 if (kstrtobool(buf, &value))
39 port_dev->early_stop = 1;
41 port_dev->early_stop = 0;
45 static DEVICE_ATTR_RW(early_stop);
47 static ssize_t disable_show(struct device *dev,
48 struct device_attribute *attr, char *buf)
50 struct usb_port *port_dev = to_usb_port(dev);
51 struct usb_device *hdev = to_usb_device(dev->parent->parent);
52 struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
53 struct usb_interface *intf = to_usb_interface(hub->intfdev);
54 int port1 = port_dev->portnum;
55 u16 portstatus, unused;
59 rc = usb_autopm_get_interface(intf);
63 usb_lock_device(hdev);
64 if (hub->disconnected) {
69 usb_hub_port_status(hub, port1, &portstatus, &unused);
70 disabled = !usb_port_is_power_on(hub, portstatus);
73 usb_unlock_device(hdev);
74 usb_autopm_put_interface(intf);
79 return sysfs_emit(buf, "%s\n", disabled ? "1" : "0");
82 static ssize_t disable_store(struct device *dev, struct device_attribute *attr,
83 const char *buf, size_t count)
85 struct usb_port *port_dev = to_usb_port(dev);
86 struct usb_device *hdev = to_usb_device(dev->parent->parent);
87 struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
88 struct usb_interface *intf = to_usb_interface(hub->intfdev);
89 int port1 = port_dev->portnum;
93 rc = kstrtobool(buf, &disabled);
97 rc = usb_autopm_get_interface(intf);
101 usb_lock_device(hdev);
102 if (hub->disconnected) {
107 if (disabled && port_dev->child)
108 usb_disconnect(&port_dev->child);
110 rc = usb_hub_set_port_power(hdev, hub, port1, !disabled);
113 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
114 if (!port_dev->is_superspeed)
115 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
122 usb_unlock_device(hdev);
123 usb_autopm_put_interface(intf);
127 static DEVICE_ATTR_RW(disable);
129 static ssize_t location_show(struct device *dev,
130 struct device_attribute *attr, char *buf)
132 struct usb_port *port_dev = to_usb_port(dev);
134 return sprintf(buf, "0x%08x\n", port_dev->location);
136 static DEVICE_ATTR_RO(location);
138 static ssize_t connect_type_show(struct device *dev,
139 struct device_attribute *attr, char *buf)
141 struct usb_port *port_dev = to_usb_port(dev);
144 switch (port_dev->connect_type) {
145 case USB_PORT_CONNECT_TYPE_HOT_PLUG:
148 case USB_PORT_CONNECT_TYPE_HARD_WIRED:
149 result = "hardwired";
151 case USB_PORT_NOT_USED:
159 return sprintf(buf, "%s\n", result);
161 static DEVICE_ATTR_RO(connect_type);
163 static ssize_t state_show(struct device *dev,
164 struct device_attribute *attr, char *buf)
166 struct usb_port *port_dev = to_usb_port(dev);
167 enum usb_device_state state = READ_ONCE(port_dev->state);
169 return sysfs_emit(buf, "%s\n", usb_state_string(state));
171 static DEVICE_ATTR_RO(state);
173 static ssize_t over_current_count_show(struct device *dev,
174 struct device_attribute *attr, char *buf)
176 struct usb_port *port_dev = to_usb_port(dev);
178 return sprintf(buf, "%u\n", port_dev->over_current_count);
180 static DEVICE_ATTR_RO(over_current_count);
182 static ssize_t quirks_show(struct device *dev,
183 struct device_attribute *attr, char *buf)
185 struct usb_port *port_dev = to_usb_port(dev);
187 return sprintf(buf, "%08x\n", port_dev->quirks);
190 static ssize_t quirks_store(struct device *dev, struct device_attribute *attr,
191 const char *buf, size_t count)
193 struct usb_port *port_dev = to_usb_port(dev);
196 if (kstrtou32(buf, 16, &value))
199 port_dev->quirks = value;
202 static DEVICE_ATTR_RW(quirks);
204 static ssize_t usb3_lpm_permit_show(struct device *dev,
205 struct device_attribute *attr, char *buf)
207 struct usb_port *port_dev = to_usb_port(dev);
210 if (port_dev->usb3_lpm_u1_permit) {
211 if (port_dev->usb3_lpm_u2_permit)
216 if (port_dev->usb3_lpm_u2_permit)
222 return sprintf(buf, "%s\n", p);
225 static ssize_t usb3_lpm_permit_store(struct device *dev,
226 struct device_attribute *attr,
227 const char *buf, size_t count)
229 struct usb_port *port_dev = to_usb_port(dev);
230 struct usb_device *udev = port_dev->child;
233 if (!strncmp(buf, "u1_u2", 5)) {
234 port_dev->usb3_lpm_u1_permit = 1;
235 port_dev->usb3_lpm_u2_permit = 1;
237 } else if (!strncmp(buf, "u1", 2)) {
238 port_dev->usb3_lpm_u1_permit = 1;
239 port_dev->usb3_lpm_u2_permit = 0;
241 } else if (!strncmp(buf, "u2", 2)) {
242 port_dev->usb3_lpm_u1_permit = 0;
243 port_dev->usb3_lpm_u2_permit = 1;
245 } else if (!strncmp(buf, "0", 1)) {
246 port_dev->usb3_lpm_u1_permit = 0;
247 port_dev->usb3_lpm_u2_permit = 0;
251 /* If device is connected to the port, disable or enable lpm
252 * to make new u1 u2 setting take effect immediately.
255 hcd = bus_to_hcd(udev->bus);
258 usb_lock_device(udev);
259 mutex_lock(hcd->bandwidth_mutex);
260 if (!usb_disable_lpm(udev))
261 usb_enable_lpm(udev);
262 mutex_unlock(hcd->bandwidth_mutex);
263 usb_unlock_device(udev);
268 static DEVICE_ATTR_RW(usb3_lpm_permit);
270 static struct attribute *port_dev_attrs[] = {
271 &dev_attr_connect_type.attr,
272 &dev_attr_state.attr,
273 &dev_attr_location.attr,
274 &dev_attr_quirks.attr,
275 &dev_attr_over_current_count.attr,
276 &dev_attr_disable.attr,
277 &dev_attr_early_stop.attr,
281 static const struct attribute_group port_dev_attr_grp = {
282 .attrs = port_dev_attrs,
285 static const struct attribute_group *port_dev_group[] = {
290 static struct attribute *port_dev_usb3_attrs[] = {
291 &dev_attr_usb3_lpm_permit.attr,
295 static const struct attribute_group port_dev_usb3_attr_grp = {
296 .attrs = port_dev_usb3_attrs,
299 static const struct attribute_group *port_dev_usb3_group[] = {
301 &port_dev_usb3_attr_grp,
305 static void usb_port_device_release(struct device *dev)
307 struct usb_port *port_dev = to_usb_port(dev);
309 kfree(port_dev->req);
314 static int usb_port_runtime_resume(struct device *dev)
316 struct usb_port *port_dev = to_usb_port(dev);
317 struct usb_device *hdev = to_usb_device(dev->parent->parent);
318 struct usb_interface *intf = to_usb_interface(dev->parent);
319 struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
320 struct usb_device *udev = port_dev->child;
321 struct usb_port *peer = port_dev->peer;
322 int port1 = port_dev->portnum;
328 set_bit(port1, hub->power_bits);
333 * Power on our usb3 peer before this usb2 port to prevent a usb3
334 * device from degrading to its usb2 connection
336 if (!port_dev->is_superspeed && peer)
337 pm_runtime_get_sync(&peer->dev);
339 retval = usb_autopm_get_interface(intf);
343 retval = usb_hub_set_port_power(hdev, hub, port1, true);
344 msleep(hub_power_on_good_delay(hub));
345 if (udev && !retval) {
347 * Our preference is to simply wait for the port to reconnect,
348 * as that is the lowest latency method to restart the port.
349 * However, there are cases where toggling port power results in
350 * the host port and the device port getting out of sync causing
351 * a link training live lock. Upon timeout, flag the port as
352 * needing warm reset recovery (to be performed later by
353 * usb_port_resume() as requested via usb_wakeup_notification())
355 if (hub_port_debounce_be_connected(hub, port1) < 0) {
356 dev_dbg(&port_dev->dev, "reconnect timeout\n");
357 if (hub_is_superspeed(hdev))
358 set_bit(port1, hub->warm_reset_bits);
361 /* Force the child awake to revalidate after the power loss. */
362 if (!test_and_set_bit(port1, hub->child_usage_bits)) {
363 pm_runtime_get_noresume(&port_dev->dev);
364 pm_request_resume(&udev->dev);
368 usb_autopm_put_interface(intf);
373 static int usb_port_runtime_suspend(struct device *dev)
375 struct usb_port *port_dev = to_usb_port(dev);
376 struct usb_device *hdev = to_usb_device(dev->parent->parent);
377 struct usb_interface *intf = to_usb_interface(dev->parent);
378 struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
379 struct usb_port *peer = port_dev->peer;
380 int port1 = port_dev->portnum;
388 if (dev_pm_qos_flags(&port_dev->dev, PM_QOS_FLAG_NO_POWER_OFF)
392 if (usb_port_block_power_off)
395 retval = usb_autopm_get_interface(intf);
399 retval = usb_hub_set_port_power(hdev, hub, port1, false);
400 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
401 if (!port_dev->is_superspeed)
402 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
403 usb_autopm_put_interface(intf);
406 * Our peer usb3 port may now be able to suspend, so
407 * asynchronously queue a suspend request to observe that this
408 * usb2 port is now off.
410 if (!port_dev->is_superspeed && peer)
411 pm_runtime_put(&peer->dev);
417 static void usb_port_shutdown(struct device *dev)
419 struct usb_port *port_dev = to_usb_port(dev);
422 usb_disable_usb2_hardware_lpm(port_dev->child);
425 static const struct dev_pm_ops usb_port_pm_ops = {
427 .runtime_suspend = usb_port_runtime_suspend,
428 .runtime_resume = usb_port_runtime_resume,
432 struct device_type usb_port_device_type = {
434 .release = usb_port_device_release,
435 .pm = &usb_port_pm_ops,
438 static struct device_driver usb_port_driver = {
440 .owner = THIS_MODULE,
441 .shutdown = usb_port_shutdown,
444 static int link_peers(struct usb_port *left, struct usb_port *right)
446 struct usb_port *ss_port, *hs_port;
449 if (left->peer == right && right->peer == left)
452 if (left->peer || right->peer) {
453 struct usb_port *lpeer = left->peer;
454 struct usb_port *rpeer = right->peer;
457 if (left->location && left->location == right->location)
462 pr_debug("usb: failed to peer %s and %s by %s (%s:%s) (%s:%s)\n",
463 dev_name(&left->dev), dev_name(&right->dev), method,
464 dev_name(&left->dev),
465 lpeer ? dev_name(&lpeer->dev) : "none",
466 dev_name(&right->dev),
467 rpeer ? dev_name(&rpeer->dev) : "none");
471 rc = sysfs_create_link(&left->dev.kobj, &right->dev.kobj, "peer");
474 rc = sysfs_create_link(&right->dev.kobj, &left->dev.kobj, "peer");
476 sysfs_remove_link(&left->dev.kobj, "peer");
481 * We need to wake the HiSpeed port to make sure we don't race
482 * setting ->peer with usb_port_runtime_suspend(). Otherwise we
483 * may miss a suspend event for the SuperSpeed port.
485 if (left->is_superspeed) {
487 WARN_ON(right->is_superspeed);
491 WARN_ON(!right->is_superspeed);
494 pm_runtime_get_sync(&hs_port->dev);
500 * The SuperSpeed reference is dropped when the HiSpeed port in
501 * this relationship suspends, i.e. when it is safe to allow a
502 * SuperSpeed connection to drop since there is no risk of a
503 * device degrading to its powered-off HiSpeed connection.
505 * Also, drop the HiSpeed ref taken above.
507 pm_runtime_get_sync(&ss_port->dev);
508 pm_runtime_put(&hs_port->dev);
513 static void link_peers_report(struct usb_port *left, struct usb_port *right)
517 rc = link_peers(left, right);
519 dev_dbg(&left->dev, "peered to %s\n", dev_name(&right->dev));
521 dev_dbg(&left->dev, "failed to peer to %s (%d)\n",
522 dev_name(&right->dev), rc);
523 pr_warn_once("usb: port power management may be unreliable\n");
524 usb_port_block_power_off = 1;
528 static void unlink_peers(struct usb_port *left, struct usb_port *right)
530 struct usb_port *ss_port, *hs_port;
532 WARN(right->peer != left || left->peer != right,
533 "%s and %s are not peers?\n",
534 dev_name(&left->dev), dev_name(&right->dev));
537 * We wake the HiSpeed port to make sure we don't race its
538 * usb_port_runtime_resume() event which takes a SuperSpeed ref
539 * when ->peer is !NULL.
541 if (left->is_superspeed) {
549 pm_runtime_get_sync(&hs_port->dev);
551 sysfs_remove_link(&left->dev.kobj, "peer");
553 sysfs_remove_link(&right->dev.kobj, "peer");
556 /* Drop the SuperSpeed ref held on behalf of the active HiSpeed port */
557 pm_runtime_put(&ss_port->dev);
559 /* Drop the ref taken above */
560 pm_runtime_put(&hs_port->dev);
564 * For each usb hub device in the system check to see if it is in the
565 * peer domain of the given port_dev, and if it is check to see if it
566 * has a port that matches the given port by location
568 static int match_location(struct usb_device *peer_hdev, void *p)
571 struct usb_hcd *hcd, *peer_hcd;
572 struct usb_port *port_dev = p, *peer;
573 struct usb_hub *peer_hub = usb_hub_to_struct_hub(peer_hdev);
574 struct usb_device *hdev = to_usb_device(port_dev->dev.parent->parent);
579 hcd = bus_to_hcd(hdev->bus);
580 peer_hcd = bus_to_hcd(peer_hdev->bus);
581 /* peer_hcd is provisional until we verify it against the known peer */
582 if (peer_hcd != hcd->shared_hcd)
585 for (port1 = 1; port1 <= peer_hdev->maxchild; port1++) {
586 peer = peer_hub->ports[port1 - 1];
587 if (peer && peer->location == port_dev->location) {
588 link_peers_report(port_dev, peer);
597 * Find the peer port either via explicit platform firmware "location"
598 * data, the peer hcd for root hubs, or the upstream peer relationship
599 * for all other hubs.
601 static void find_and_link_peer(struct usb_hub *hub, int port1)
603 struct usb_port *port_dev = hub->ports[port1 - 1], *peer;
604 struct usb_device *hdev = hub->hdev;
605 struct usb_device *peer_hdev;
606 struct usb_hub *peer_hub;
609 * If location data is available then we can only peer this port
610 * by a location match, not the default peer (lest we create a
611 * situation where we need to go back and undo a default peering
612 * when the port is later peered by location data)
614 if (port_dev->location) {
615 /* we link the peer in match_location() if found */
616 usb_for_each_dev(port_dev, match_location);
618 } else if (!hdev->parent) {
619 struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
620 struct usb_hcd *peer_hcd = hcd->shared_hcd;
625 peer_hdev = peer_hcd->self.root_hub;
627 struct usb_port *upstream;
628 struct usb_device *parent = hdev->parent;
629 struct usb_hub *parent_hub = usb_hub_to_struct_hub(parent);
634 upstream = parent_hub->ports[hdev->portnum - 1];
635 if (!upstream || !upstream->peer)
638 peer_hdev = upstream->peer->child;
641 peer_hub = usb_hub_to_struct_hub(peer_hdev);
642 if (!peer_hub || port1 > peer_hdev->maxchild)
646 * we found a valid default peer, last check is to make sure it
647 * does not have location data
649 peer = peer_hub->ports[port1 - 1];
650 if (peer && peer->location == 0)
651 link_peers_report(port_dev, peer);
654 static int connector_bind(struct device *dev, struct device *connector, void *data)
656 struct usb_port *port_dev = to_usb_port(dev);
659 ret = sysfs_create_link(&dev->kobj, &connector->kobj, "connector");
663 ret = sysfs_create_link(&connector->kobj, &dev->kobj, dev_name(dev));
665 sysfs_remove_link(&dev->kobj, "connector");
669 port_dev->connector = data;
672 * If there is already USB device connected to the port, letting the
673 * Type-C connector know about it immediately.
676 typec_attach(port_dev->connector, &port_dev->child->dev);
681 static void connector_unbind(struct device *dev, struct device *connector, void *data)
683 struct usb_port *port_dev = to_usb_port(dev);
685 sysfs_remove_link(&connector->kobj, dev_name(dev));
686 sysfs_remove_link(&dev->kobj, "connector");
687 port_dev->connector = NULL;
690 static const struct component_ops connector_ops = {
691 .bind = connector_bind,
692 .unbind = connector_unbind,
695 int usb_hub_create_port_device(struct usb_hub *hub, int port1)
697 struct usb_port *port_dev;
698 struct usb_device *hdev = hub->hdev;
701 port_dev = kzalloc(sizeof(*port_dev), GFP_KERNEL);
705 port_dev->req = kzalloc(sizeof(*(port_dev->req)), GFP_KERNEL);
706 if (!port_dev->req) {
711 hub->ports[port1 - 1] = port_dev;
712 port_dev->portnum = port1;
713 set_bit(port1, hub->power_bits);
714 port_dev->dev.parent = hub->intfdev;
715 if (hub_is_superspeed(hdev)) {
716 port_dev->is_superspeed = 1;
717 port_dev->usb3_lpm_u1_permit = 1;
718 port_dev->usb3_lpm_u2_permit = 1;
719 port_dev->dev.groups = port_dev_usb3_group;
721 port_dev->dev.groups = port_dev_group;
722 port_dev->dev.type = &usb_port_device_type;
723 port_dev->dev.driver = &usb_port_driver;
724 dev_set_name(&port_dev->dev, "%s-port%d", dev_name(&hub->hdev->dev),
726 mutex_init(&port_dev->status_lock);
727 retval = device_register(&port_dev->dev);
729 put_device(&port_dev->dev);
733 port_dev->state_kn = sysfs_get_dirent(port_dev->dev.kobj.sd, "state");
734 if (!port_dev->state_kn) {
735 dev_err(&port_dev->dev, "failed to sysfs_get_dirent 'state'\n");
740 /* Set default policy of port-poweroff disabled. */
741 retval = dev_pm_qos_add_request(&port_dev->dev, port_dev->req,
742 DEV_PM_QOS_FLAGS, PM_QOS_FLAG_NO_POWER_OFF);
747 retval = component_add(&port_dev->dev, &connector_ops);
749 dev_warn(&port_dev->dev, "failed to add component\n");
753 find_and_link_peer(hub, port1);
756 * Enable runtime pm and hold a refernce that hub_configure()
757 * will drop once the PM_QOS_NO_POWER_OFF flag state has been set
758 * and the hub has been fully registered (hdev->maxchild set).
760 pm_runtime_set_active(&port_dev->dev);
761 pm_runtime_get_noresume(&port_dev->dev);
762 pm_runtime_enable(&port_dev->dev);
763 device_enable_async_suspend(&port_dev->dev);
766 * Keep hidden the ability to enable port-poweroff if the hub
767 * does not support power switching.
769 if (!hub_is_port_power_switchable(hub))
772 /* Attempt to let userspace take over the policy. */
773 retval = dev_pm_qos_expose_flags(&port_dev->dev,
774 PM_QOS_FLAG_NO_POWER_OFF);
776 dev_warn(&port_dev->dev, "failed to expose pm_qos_no_poweroff\n");
780 /* Userspace owns the policy, drop the kernel 'no_poweroff' request. */
781 retval = dev_pm_qos_remove_request(port_dev->req);
783 kfree(port_dev->req);
784 port_dev->req = NULL;
789 sysfs_put(port_dev->state_kn);
791 device_unregister(&port_dev->dev);
796 void usb_hub_remove_port_device(struct usb_hub *hub, int port1)
798 struct usb_port *port_dev = hub->ports[port1 - 1];
799 struct usb_port *peer;
801 peer = port_dev->peer;
803 unlink_peers(port_dev, peer);
804 component_del(&port_dev->dev, &connector_ops);
805 sysfs_put(port_dev->state_kn);
806 device_unregister(&port_dev->dev);