// SPDX-License-Identifier: GPL-2.0 /* * usb port device code * * Copyright (C) 2012 Intel Corp * * Author: Lan Tianyu */ #include #include #include #include #include "hub.h" static int usb_port_block_power_off; static const struct attribute_group *port_dev_group[]; static ssize_t early_stop_show(struct device *dev, struct device_attribute *attr, char *buf) { struct usb_port *port_dev = to_usb_port(dev); return sysfs_emit(buf, "%s\n", port_dev->early_stop ? "yes" : "no"); } static ssize_t early_stop_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct usb_port *port_dev = to_usb_port(dev); bool value; if (kstrtobool(buf, &value)) return -EINVAL; if (value) port_dev->early_stop = 1; else port_dev->early_stop = 0; return count; } static DEVICE_ATTR_RW(early_stop); static ssize_t disable_show(struct device *dev, struct device_attribute *attr, char *buf) { struct usb_port *port_dev = to_usb_port(dev); struct usb_device *hdev = to_usb_device(dev->parent->parent); struct usb_hub *hub = usb_hub_to_struct_hub(hdev); struct usb_interface *intf = to_usb_interface(hub->intfdev); int port1 = port_dev->portnum; u16 portstatus, unused; bool disabled; int rc; struct kernfs_node *kn; hub_get(hub); rc = usb_autopm_get_interface(intf); if (rc < 0) goto out_hub_get; /* * Prevent deadlock if another process is concurrently * trying to unregister hdev. */ kn = sysfs_break_active_protection(&dev->kobj, &attr->attr); if (!kn) { rc = -ENODEV; goto out_autopm; } usb_lock_device(hdev); if (hub->disconnected) { rc = -ENODEV; goto out_hdev_lock; } usb_hub_port_status(hub, port1, &portstatus, &unused); disabled = !usb_port_is_power_on(hub, portstatus); out_hdev_lock: usb_unlock_device(hdev); sysfs_unbreak_active_protection(kn); out_autopm: usb_autopm_put_interface(intf); out_hub_get: hub_put(hub); if (rc) return rc; return sysfs_emit(buf, "%s\n", disabled ? "1" : "0"); } static ssize_t disable_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct usb_port *port_dev = to_usb_port(dev); struct usb_device *hdev = to_usb_device(dev->parent->parent); struct usb_hub *hub = usb_hub_to_struct_hub(hdev); struct usb_interface *intf = to_usb_interface(hub->intfdev); int port1 = port_dev->portnum; bool disabled; int rc; struct kernfs_node *kn; rc = kstrtobool(buf, &disabled); if (rc) return rc; hub_get(hub); rc = usb_autopm_get_interface(intf); if (rc < 0) goto out_hub_get; /* * Prevent deadlock if another process is concurrently * trying to unregister hdev. */ kn = sysfs_break_active_protection(&dev->kobj, &attr->attr); if (!kn) { rc = -ENODEV; goto out_autopm; } usb_lock_device(hdev); if (hub->disconnected) { rc = -ENODEV; goto out_hdev_lock; } if (disabled && port_dev->child) usb_disconnect(&port_dev->child); rc = usb_hub_set_port_power(hdev, hub, port1, !disabled); if (disabled) { usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION); if (!port_dev->is_superspeed) usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE); } if (!rc) rc = count; out_hdev_lock: usb_unlock_device(hdev); sysfs_unbreak_active_protection(kn); out_autopm: usb_autopm_put_interface(intf); out_hub_get: hub_put(hub); return rc; } static DEVICE_ATTR_RW(disable); static ssize_t location_show(struct device *dev, struct device_attribute *attr, char *buf) { struct usb_port *port_dev = to_usb_port(dev); return sprintf(buf, "0x%08x\n", port_dev->location); } static DEVICE_ATTR_RO(location); static ssize_t connect_type_show(struct device *dev, struct device_attribute *attr, char *buf) { struct usb_port *port_dev = to_usb_port(dev); char *result; switch (port_dev->connect_type) { case USB_PORT_CONNECT_TYPE_HOT_PLUG: result = "hotplug"; break; case USB_PORT_CONNECT_TYPE_HARD_WIRED: result = "hardwired"; break; case USB_PORT_NOT_USED: result = "not used"; break; default: result = "unknown"; break; } return sprintf(buf, "%s\n", result); } static DEVICE_ATTR_RO(connect_type); static ssize_t state_show(struct device *dev, struct device_attribute *attr, char *buf) { struct usb_port *port_dev = to_usb_port(dev); enum usb_device_state state = READ_ONCE(port_dev->state); return sysfs_emit(buf, "%s\n", usb_state_string(state)); } static DEVICE_ATTR_RO(state); static ssize_t over_current_count_show(struct device *dev, struct device_attribute *attr, char *buf) { struct usb_port *port_dev = to_usb_port(dev); return sprintf(buf, "%u\n", port_dev->over_current_count); } static DEVICE_ATTR_RO(over_current_count); static ssize_t quirks_show(struct device *dev, struct device_attribute *attr, char *buf) { struct usb_port *port_dev = to_usb_port(dev); return sprintf(buf, "%08x\n", port_dev->quirks); } static ssize_t quirks_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct usb_port *port_dev = to_usb_port(dev); u32 value; if (kstrtou32(buf, 16, &value)) return -EINVAL; port_dev->quirks = value; return count; } static DEVICE_ATTR_RW(quirks); static ssize_t usb3_lpm_permit_show(struct device *dev, struct device_attribute *attr, char *buf) { struct usb_port *port_dev = to_usb_port(dev); const char *p; if (port_dev->usb3_lpm_u1_permit) { if (port_dev->usb3_lpm_u2_permit) p = "u1_u2"; else p = "u1"; } else { if (port_dev->usb3_lpm_u2_permit) p = "u2"; else p = "0"; } return sprintf(buf, "%s\n", p); } static ssize_t usb3_lpm_permit_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct usb_port *port_dev = to_usb_port(dev); struct usb_device *udev = port_dev->child; struct usb_hcd *hcd; if (!strncmp(buf, "u1_u2", 5)) { port_dev->usb3_lpm_u1_permit = 1; port_dev->usb3_lpm_u2_permit = 1; } else if (!strncmp(buf, "u1", 2)) { port_dev->usb3_lpm_u1_permit = 1; port_dev->usb3_lpm_u2_permit = 0; } else if (!strncmp(buf, "u2", 2)) { port_dev->usb3_lpm_u1_permit = 0; port_dev->usb3_lpm_u2_permit = 1; } else if (!strncmp(buf, "0", 1)) { port_dev->usb3_lpm_u1_permit = 0; port_dev->usb3_lpm_u2_permit = 0; } else return -EINVAL; /* If device is connected to the port, disable or enable lpm * to make new u1 u2 setting take effect immediately. */ if (udev) { hcd = bus_to_hcd(udev->bus); if (!hcd) return -EINVAL; usb_lock_device(udev); mutex_lock(hcd->bandwidth_mutex); if (!usb_disable_lpm(udev)) usb_enable_lpm(udev); mutex_unlock(hcd->bandwidth_mutex); usb_unlock_device(udev); } return count; } static DEVICE_ATTR_RW(usb3_lpm_permit); static struct attribute *port_dev_attrs[] = { &dev_attr_connect_type.attr, &dev_attr_state.attr, &dev_attr_location.attr, &dev_attr_quirks.attr, &dev_attr_over_current_count.attr, &dev_attr_disable.attr, &dev_attr_early_stop.attr, NULL, }; static const struct attribute_group port_dev_attr_grp = { .attrs = port_dev_attrs, }; static const struct attribute_group *port_dev_group[] = { &port_dev_attr_grp, NULL, }; static struct attribute *port_dev_usb3_attrs[] = { &dev_attr_usb3_lpm_permit.attr, NULL, }; static const struct attribute_group port_dev_usb3_attr_grp = { .attrs = port_dev_usb3_attrs, }; static const struct attribute_group *port_dev_usb3_group[] = { &port_dev_attr_grp, &port_dev_usb3_attr_grp, NULL, }; static void usb_port_device_release(struct device *dev) { struct usb_port *port_dev = to_usb_port(dev); kfree(port_dev->req); kfree(port_dev); } #ifdef CONFIG_PM static int usb_port_runtime_resume(struct device *dev) { struct usb_port *port_dev = to_usb_port(dev); struct usb_device *hdev = to_usb_device(dev->parent->parent); struct usb_interface *intf = to_usb_interface(dev->parent); struct usb_hub *hub = usb_hub_to_struct_hub(hdev); struct usb_device *udev = port_dev->child; struct usb_port *peer = port_dev->peer; int port1 = port_dev->portnum; int retval; if (!hub) return -EINVAL; if (hub->in_reset) { set_bit(port1, hub->power_bits); return 0; } /* * Power on our usb3 peer before this usb2 port to prevent a usb3 * device from degrading to its usb2 connection */ if (!port_dev->is_superspeed && peer) pm_runtime_get_sync(&peer->dev); retval = usb_autopm_get_interface(intf); if (retval < 0) return retval; retval = usb_hub_set_port_power(hdev, hub, port1, true); msleep(hub_power_on_good_delay(hub)); if (udev && !retval) { /* * Our preference is to simply wait for the port to reconnect, * as that is the lowest latency method to restart the port. * However, there are cases where toggling port power results in * the host port and the device port getting out of sync causing * a link training live lock. Upon timeout, flag the port as * needing warm reset recovery (to be performed later by * usb_port_resume() as requested via usb_wakeup_notification()) */ if (hub_port_debounce_be_connected(hub, port1) < 0) { dev_dbg(&port_dev->dev, "reconnect timeout\n"); if (hub_is_superspeed(hdev)) set_bit(port1, hub->warm_reset_bits); } /* Force the child awake to revalidate after the power loss. */ if (!test_and_set_bit(port1, hub->child_usage_bits)) { pm_runtime_get_noresume(&port_dev->dev); pm_request_resume(&udev->dev); } } usb_autopm_put_interface(intf); return retval; } static int usb_port_runtime_suspend(struct device *dev) { struct usb_port *port_dev = to_usb_port(dev); struct usb_device *hdev = to_usb_device(dev->parent->parent); struct usb_interface *intf = to_usb_interface(dev->parent); struct usb_hub *hub = usb_hub_to_struct_hub(hdev); struct usb_port *peer = port_dev->peer; int port1 = port_dev->portnum; int retval; if (!hub) return -EINVAL; if (hub->in_reset) return -EBUSY; if (dev_pm_qos_flags(&port_dev->dev, PM_QOS_FLAG_NO_POWER_OFF) == PM_QOS_FLAGS_ALL) return -EAGAIN; if (usb_port_block_power_off) return -EBUSY; retval = usb_autopm_get_interface(intf); if (retval < 0) return retval; retval = usb_hub_set_port_power(hdev, hub, port1, false); usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION); if (!port_dev->is_superspeed) usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE); usb_autopm_put_interface(intf); /* * Our peer usb3 port may now be able to suspend, so * asynchronously queue a suspend request to observe that this * usb2 port is now off. */ if (!port_dev->is_superspeed && peer) pm_runtime_put(&peer->dev); return retval; } #endif static void usb_port_shutdown(struct device *dev) { struct usb_port *port_dev = to_usb_port(dev); if (port_dev->child) usb_disable_usb2_hardware_lpm(port_dev->child); } static const struct dev_pm_ops usb_port_pm_ops = { #ifdef CONFIG_PM .runtime_suspend = usb_port_runtime_suspend, .runtime_resume = usb_port_runtime_resume, #endif }; struct device_type usb_port_device_type = { .name = "usb_port", .release = usb_port_device_release, .pm = &usb_port_pm_ops, }; static struct device_driver usb_port_driver = { .name = "usb", .owner = THIS_MODULE, .shutdown = usb_port_shutdown, }; static int link_peers(struct usb_port *left, struct usb_port *right) { struct usb_port *ss_port, *hs_port; int rc; if (left->peer == right && right->peer == left) return 0; if (left->peer || right->peer) { struct usb_port *lpeer = left->peer; struct usb_port *rpeer = right->peer; char *method; if (left->location && left->location == right->location) method = "location"; else method = "default"; pr_debug("usb: failed to peer %s and %s by %s (%s:%s) (%s:%s)\n", dev_name(&left->dev), dev_name(&right->dev), method, dev_name(&left->dev), lpeer ? dev_name(&lpeer->dev) : "none", dev_name(&right->dev), rpeer ? dev_name(&rpeer->dev) : "none"); return -EBUSY; } rc = sysfs_create_link(&left->dev.kobj, &right->dev.kobj, "peer"); if (rc) return rc; rc = sysfs_create_link(&right->dev.kobj, &left->dev.kobj, "peer"); if (rc) { sysfs_remove_link(&left->dev.kobj, "peer"); return rc; } /* * We need to wake the HiSpeed port to make sure we don't race * setting ->peer with usb_port_runtime_suspend(). Otherwise we * may miss a suspend event for the SuperSpeed port. */ if (left->is_superspeed) { ss_port = left; WARN_ON(right->is_superspeed); hs_port = right; } else { ss_port = right; WARN_ON(!right->is_superspeed); hs_port = left; } pm_runtime_get_sync(&hs_port->dev); left->peer = right; right->peer = left; /* * The SuperSpeed reference is dropped when the HiSpeed port in * this relationship suspends, i.e. when it is safe to allow a * SuperSpeed connection to drop since there is no risk of a * device degrading to its powered-off HiSpeed connection. * * Also, drop the HiSpeed ref taken above. */ pm_runtime_get_sync(&ss_port->dev); pm_runtime_put(&hs_port->dev); return 0; } static void link_peers_report(struct usb_port *left, struct usb_port *right) { int rc; rc = link_peers(left, right); if (rc == 0) { dev_dbg(&left->dev, "peered to %s\n", dev_name(&right->dev)); } else { dev_dbg(&left->dev, "failed to peer to %s (%d)\n", dev_name(&right->dev), rc); pr_warn_once("usb: port power management may be unreliable\n"); usb_port_block_power_off = 1; } } static void unlink_peers(struct usb_port *left, struct usb_port *right) { struct usb_port *ss_port, *hs_port; WARN(right->peer != left || left->peer != right, "%s and %s are not peers?\n", dev_name(&left->dev), dev_name(&right->dev)); /* * We wake the HiSpeed port to make sure we don't race its * usb_port_runtime_resume() event which takes a SuperSpeed ref * when ->peer is !NULL. */ if (left->is_superspeed) { ss_port = left; hs_port = right; } else { ss_port = right; hs_port = left; } pm_runtime_get_sync(&hs_port->dev); sysfs_remove_link(&left->dev.kobj, "peer"); right->peer = NULL; sysfs_remove_link(&right->dev.kobj, "peer"); left->peer = NULL; /* Drop the SuperSpeed ref held on behalf of the active HiSpeed port */ pm_runtime_put(&ss_port->dev); /* Drop the ref taken above */ pm_runtime_put(&hs_port->dev); } /* * For each usb hub device in the system check to see if it is in the * peer domain of the given port_dev, and if it is check to see if it * has a port that matches the given port by location */ static int match_location(struct usb_device *peer_hdev, void *p) { int port1; struct usb_hcd *hcd, *peer_hcd; struct usb_port *port_dev = p, *peer; struct usb_hub *peer_hub = usb_hub_to_struct_hub(peer_hdev); struct usb_device *hdev = to_usb_device(port_dev->dev.parent->parent); if (!peer_hub || port_dev->connect_type == USB_PORT_NOT_USED) return 0; hcd = bus_to_hcd(hdev->bus); peer_hcd = bus_to_hcd(peer_hdev->bus); /* peer_hcd is provisional until we verify it against the known peer */ if (peer_hcd != hcd->shared_hcd) return 0; for (port1 = 1; port1 <= peer_hdev->maxchild; port1++) { peer = peer_hub->ports[port1 - 1]; if (peer && peer->connect_type != USB_PORT_NOT_USED && peer->location == port_dev->location) { link_peers_report(port_dev, peer); return 1; /* done */ } } return 0; } /* * Find the peer port either via explicit platform firmware "location" * data, the peer hcd for root hubs, or the upstream peer relationship * for all other hubs. */ static void find_and_link_peer(struct usb_hub *hub, int port1) { struct usb_port *port_dev = hub->ports[port1 - 1], *peer; struct usb_device *hdev = hub->hdev; struct usb_device *peer_hdev; struct usb_hub *peer_hub; /* * If location data is available then we can only peer this port * by a location match, not the default peer (lest we create a * situation where we need to go back and undo a default peering * when the port is later peered by location data) */ if (port_dev->location) { /* we link the peer in match_location() if found */ usb_for_each_dev(port_dev, match_location); return; } else if (!hdev->parent) { struct usb_hcd *hcd = bus_to_hcd(hdev->bus); struct usb_hcd *peer_hcd = hcd->shared_hcd; if (!peer_hcd) return; peer_hdev = peer_hcd->self.root_hub; } else { struct usb_port *upstream; struct usb_device *parent = hdev->parent; struct usb_hub *parent_hub = usb_hub_to_struct_hub(parent); if (!parent_hub) return; upstream = parent_hub->ports[hdev->portnum - 1]; if (!upstream || !upstream->peer) return; peer_hdev = upstream->peer->child; } peer_hub = usb_hub_to_struct_hub(peer_hdev); if (!peer_hub || port1 > peer_hdev->maxchild) return; /* * we found a valid default peer, last check is to make sure it * does not have location data */ peer = peer_hub->ports[port1 - 1]; if (peer && peer->location == 0) link_peers_report(port_dev, peer); } static int connector_bind(struct device *dev, struct device *connector, void *data) { int ret; ret = sysfs_create_link(&dev->kobj, &connector->kobj, "connector"); if (ret) return ret; ret = sysfs_create_link(&connector->kobj, &dev->kobj, dev_name(dev)); if (ret) sysfs_remove_link(&dev->kobj, "connector"); return ret; } static void connector_unbind(struct device *dev, struct device *connector, void *data) { sysfs_remove_link(&connector->kobj, dev_name(dev)); sysfs_remove_link(&dev->kobj, "connector"); } static const struct component_ops connector_ops = { .bind = connector_bind, .unbind = connector_unbind, }; int usb_hub_create_port_device(struct usb_hub *hub, int port1) { struct usb_port *port_dev; struct usb_device *hdev = hub->hdev; int retval; port_dev = kzalloc(sizeof(*port_dev), GFP_KERNEL); if (!port_dev) return -ENOMEM; port_dev->req = kzalloc(sizeof(*(port_dev->req)), GFP_KERNEL); if (!port_dev->req) { kfree(port_dev); return -ENOMEM; } hub->ports[port1 - 1] = port_dev; port_dev->portnum = port1; set_bit(port1, hub->power_bits); port_dev->dev.parent = hub->intfdev; if (hub_is_superspeed(hdev)) { port_dev->usb3_lpm_u1_permit = 1; port_dev->usb3_lpm_u2_permit = 1; port_dev->dev.groups = port_dev_usb3_group; } else port_dev->dev.groups = port_dev_group; port_dev->dev.type = &usb_port_device_type; port_dev->dev.driver = &usb_port_driver; if (hub_is_superspeed(hub->hdev)) port_dev->is_superspeed = 1; dev_set_name(&port_dev->dev, "%s-port%d", dev_name(&hub->hdev->dev), port1); mutex_init(&port_dev->status_lock); retval = device_register(&port_dev->dev); if (retval) { put_device(&port_dev->dev); return retval; } port_dev->state_kn = sysfs_get_dirent(port_dev->dev.kobj.sd, "state"); if (!port_dev->state_kn) { dev_err(&port_dev->dev, "failed to sysfs_get_dirent 'state'\n"); retval = -ENODEV; goto err_unregister; } /* Set default policy of port-poweroff disabled. */ retval = dev_pm_qos_add_request(&port_dev->dev, port_dev->req, DEV_PM_QOS_FLAGS, PM_QOS_FLAG_NO_POWER_OFF); if (retval < 0) { goto err_put_kn; } retval = component_add(&port_dev->dev, &connector_ops); if (retval) { dev_warn(&port_dev->dev, "failed to add component\n"); goto err_put_kn; } find_and_link_peer(hub, port1); /* * Enable runtime pm and hold a refernce that hub_configure() * will drop once the PM_QOS_NO_POWER_OFF flag state has been set * and the hub has been fully registered (hdev->maxchild set). */ pm_runtime_set_active(&port_dev->dev); pm_runtime_get_noresume(&port_dev->dev); pm_runtime_enable(&port_dev->dev); device_enable_async_suspend(&port_dev->dev); /* * Keep hidden the ability to enable port-poweroff if the hub * does not support power switching. */ if (!hub_is_port_power_switchable(hub)) return 0; /* Attempt to let userspace take over the policy. */ retval = dev_pm_qos_expose_flags(&port_dev->dev, PM_QOS_FLAG_NO_POWER_OFF); if (retval < 0) { dev_warn(&port_dev->dev, "failed to expose pm_qos_no_poweroff\n"); return 0; } /* Userspace owns the policy, drop the kernel 'no_poweroff' request. */ retval = dev_pm_qos_remove_request(port_dev->req); if (retval >= 0) { kfree(port_dev->req); port_dev->req = NULL; } return 0; err_put_kn: sysfs_put(port_dev->state_kn); err_unregister: device_unregister(&port_dev->dev); return retval; } void usb_hub_remove_port_device(struct usb_hub *hub, int port1) { struct usb_port *port_dev = hub->ports[port1 - 1]; struct usb_port *peer; peer = port_dev->peer; if (peer) unlink_peers(port_dev, peer); component_del(&port_dev->dev, &connector_ops); sysfs_put(port_dev->state_kn); device_unregister(&port_dev->dev); }