diff options
Diffstat (limited to 'drivers/usb/core/port.c')
| -rw-r--r-- | drivers/usb/core/port.c | 741 |
1 files changed, 741 insertions, 0 deletions
diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c new file mode 100644 index 000000000..38c1a4f4f --- /dev/null +++ b/drivers/usb/core/port.c @@ -0,0 +1,741 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * usb port device code + * + * Copyright (C) 2012 Intel Corp + * + * Author: Lan Tianyu <tianyu.lan@intel.com> + */ + +#include <linux/slab.h> +#include <linux/pm_qos.h> +#include <linux/component.h> + +#include "hub.h" + +static int usb_port_block_power_off; + +static const struct attribute_group *port_dev_group[]; + +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; + + rc = usb_autopm_get_interface(intf); + if (rc < 0) + return rc; + + 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); + usb_autopm_put_interface(intf); + + 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; + + rc = strtobool(buf, &disabled); + if (rc) + return rc; + + rc = usb_autopm_get_interface(intf); + if (rc < 0) + return rc; + + 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); + usb_autopm_put_interface(intf); + + 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 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_location.attr, + &dev_attr_quirks.attr, + &dev_attr_over_current_count.attr, + &dev_attr_disable.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) + 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->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; + } + + /* 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) { + device_unregister(&port_dev->dev); + return retval; + } + + retval = component_add(&port_dev->dev, &connector_ops); + if (retval) { + dev_warn(&port_dev->dev, "failed to add component\n"); + device_unregister(&port_dev->dev); + return retval; + } + + 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; +} + +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); + device_unregister(&port_dev->dev); +} |