📄 hub.c
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return 0; hub_disconnect (intf); return -ENODEV;}static inthub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data){ struct usb_device *hdev = interface_to_usbdev (intf); /* assert ifno == 0 (part of hub spec) */ switch (code) { case USBDEVFS_HUB_PORTINFO: { struct usbdevfs_hub_portinfo *info = user_data; int i; spin_lock_irq(&device_state_lock); if (hdev->devnum <= 0) info->nports = 0; else { info->nports = hdev->maxchild; for (i = 0; i < info->nports; i++) { if (hdev->children[i] == NULL) info->port[i] = 0; else info->port[i] = hdev->children[i]->devnum; } } spin_unlock_irq(&device_state_lock); return info->nports + 1; } default: return -ENOSYS; }}/* grab device/port lock, returning index of that port (zero based). * protects the upstream link used by this device from concurrent * tree operations like suspend, resume, reset, and disconnect, which * apply to everything downstream of a given port. */static int locktree(struct usb_device *udev){ int t; struct usb_device *hdev; if (!udev) return -ENODEV; /* root hub is always the first lock in the series */ hdev = udev->parent; if (!hdev) { usb_lock_device(udev); return 0; } /* on the path from root to us, lock everything from * top down, dropping parent locks when not needed */ t = locktree(hdev); if (t < 0) return t; /* everything is fail-fast once disconnect * processing starts */ if (udev->state == USB_STATE_NOTATTACHED) { usb_unlock_device(hdev); return -ENODEV; } /* when everyone grabs locks top->bottom, * non-overlapping work may be concurrent */ usb_lock_device(udev); usb_unlock_device(hdev); return udev->portnum;}static void recursively_mark_NOTATTACHED(struct usb_device *udev){ int i; for (i = 0; i < udev->maxchild; ++i) { if (udev->children[i]) recursively_mark_NOTATTACHED(udev->children[i]); } if (udev->state == USB_STATE_SUSPENDED) udev->discon_suspended = 1; udev->state = USB_STATE_NOTATTACHED;}/** * usb_set_device_state - change a device's current state (usbcore, hcds) * @udev: pointer to device whose state should be changed * @new_state: new state value to be stored * * udev->state is _not_ fully protected by the device lock. Although * most transitions are made only while holding the lock, the state can * can change to USB_STATE_NOTATTACHED at almost any time. This * is so that devices can be marked as disconnected as soon as possible, * without having to wait for any semaphores to be released. As a result, * all changes to any device's state must be protected by the * device_state_lock spinlock. * * Once a device has been added to the device tree, all changes to its state * should be made using this routine. The state should _not_ be set directly. * * If udev->state is already USB_STATE_NOTATTACHED then no change is made. * Otherwise udev->state is set to new_state, and if new_state is * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set * to USB_STATE_NOTATTACHED. */void usb_set_device_state(struct usb_device *udev, enum usb_device_state new_state){ unsigned long flags; spin_lock_irqsave(&device_state_lock, flags); if (udev->state == USB_STATE_NOTATTACHED) ; /* do nothing */ else if (new_state != USB_STATE_NOTATTACHED) { /* root hub wakeup capabilities are managed out-of-band * and may involve silicon errata ... ignore them here. */ if (udev->parent) { if (udev->state == USB_STATE_SUSPENDED || new_state == USB_STATE_SUSPENDED) ; /* No change to wakeup settings */ else if (new_state == USB_STATE_CONFIGURED) device_init_wakeup(&udev->dev, (udev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_WAKEUP)); else device_init_wakeup(&udev->dev, 0); } udev->state = new_state; } else recursively_mark_NOTATTACHED(udev); spin_unlock_irqrestore(&device_state_lock, flags);}/** * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power * @rhdev: struct usb_device for the root hub * * The USB host controller driver calls this function when its root hub * is resumed and Vbus power has been interrupted or the controller * has been reset. The routine marks all the children of the root hub * as NOTATTACHED and marks logical connect-change events on their ports. */void usb_root_hub_lost_power(struct usb_device *rhdev){ struct usb_hub *hub; int port1; unsigned long flags; dev_warn(&rhdev->dev, "root hub lost power or was reset\n"); /* Make sure no potential wakeup events get lost, * by forcing the root hub to be resumed. */ rhdev->dev.power.prev_state.event = PM_EVENT_ON; spin_lock_irqsave(&device_state_lock, flags); hub = hdev_to_hub(rhdev); for (port1 = 1; port1 <= rhdev->maxchild; ++port1) { if (rhdev->children[port1 - 1]) { recursively_mark_NOTATTACHED( rhdev->children[port1 - 1]); set_bit(port1, hub->change_bits); } } spin_unlock_irqrestore(&device_state_lock, flags);}EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);static void choose_address(struct usb_device *udev){ int devnum; struct usb_bus *bus = udev->bus; /* If khubd ever becomes multithreaded, this will need a lock */ /* Try to allocate the next devnum beginning at bus->devnum_next. */ devnum = find_next_zero_bit(bus->devmap.devicemap, 128, bus->devnum_next); if (devnum >= 128) devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1); bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1); if (devnum < 128) { set_bit(devnum, bus->devmap.devicemap); udev->devnum = devnum; }}static void release_address(struct usb_device *udev){ if (udev->devnum > 0) { clear_bit(udev->devnum, udev->bus->devmap.devicemap); udev->devnum = -1; }}static void usb_stop_pm(struct usb_device *udev){ /* Synchronize with the ksuspend thread to prevent any more * autosuspend requests from being submitted, and decrement * the parent's count of unsuspended children. */ usb_pm_lock(udev); if (udev->parent && !udev->discon_suspended) usb_autosuspend_device(udev->parent); usb_pm_unlock(udev); /* Stop any autosuspend requests already submitted */ cancel_rearming_delayed_work(&udev->autosuspend);}/** * usb_disconnect - disconnect a device (usbcore-internal) * @pdev: pointer to device being disconnected * Context: !in_interrupt () * * Something got disconnected. Get rid of it and all of its children. * * If *pdev is a normal device then the parent hub must already be locked. * If *pdev is a root hub then this routine will acquire the * usb_bus_list_lock on behalf of the caller. * * Only hub drivers (including virtual root hub drivers for host * controllers) should ever call this. * * This call is synchronous, and may not be used in an interrupt context. */void usb_disconnect(struct usb_device **pdev){ struct usb_device *udev = *pdev; int i; if (!udev) { pr_debug ("%s nodev\n", __FUNCTION__); return; } /* mark the device as inactive, so any further urb submissions for * this device (and any of its children) will fail immediately. * this quiesces everyting except pending urbs. */ usb_set_device_state(udev, USB_STATE_NOTATTACHED); dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum); usb_lock_device(udev); /* Free up all the children before we remove this device */ for (i = 0; i < USB_MAXCHILDREN; i++) { if (udev->children[i]) usb_disconnect(&udev->children[i]); } /* deallocate hcd/hardware state ... nuking all pending urbs and * cleaning up all state associated with the current configuration * so that the hardware is now fully quiesced. */ dev_dbg (&udev->dev, "unregistering device\n"); usb_disable_device(udev, 0); usb_unlock_device(udev); /* Unregister the device. The device driver is responsible * for removing the device files from usbfs and sysfs and for * de-configuring the device. */ device_del(&udev->dev); /* Free the device number and delete the parent's children[] * (or root_hub) pointer. */ release_address(udev); /* Avoid races with recursively_mark_NOTATTACHED() */ spin_lock_irq(&device_state_lock); *pdev = NULL; spin_unlock_irq(&device_state_lock); usb_stop_pm(udev); put_device(&udev->dev);}static inline void show_string(struct usb_device *udev, char *id, char *string){}#include "otg_whitelist.h"static int __usb_port_suspend(struct usb_device *, int port1);/** * usb_new_device - perform initial device setup (usbcore-internal) * @udev: newly addressed device (in ADDRESS state) * * This is called with devices which have been enumerated, but not yet * configured. The device descriptor is available, but not descriptors * for any device configuration. The caller must have locked either * the parent hub (if udev is a normal device) or else the * usb_bus_list_lock (if udev is a root hub). The parent's pointer to * udev has already been installed, but udev is not yet visible through * sysfs or other filesystem code. * * It will return if the device is configured properly or not. Zero if * the interface was registered with the driver core; else a negative * errno value. * * This call is synchronous, and may not be used in an interrupt context. * * Only the hub driver or root-hub registrar should ever call this. */int usb_new_device(struct usb_device *udev){ int err; /* Determine quirks */ usb_detect_quirks(udev); err = usb_get_configuration(udev); if (err < 0) { dev_err(&udev->dev, "can't read configurations, error %d\n", err); goto fail; } /* read the standard strings and cache them if present */ udev->product = usb_cache_string(udev, udev->descriptor.iProduct); udev->manufacturer = usb_cache_string(udev, udev->descriptor.iManufacturer); udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber); /* Tell the world! */ dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, " "SerialNumber=%d\n", udev->descriptor.iManufacturer, udev->descriptor.iProduct, udev->descriptor.iSerialNumber); show_string(udev, "Product", udev->product); show_string(udev, "Manufacturer", udev->manufacturer); show_string(udev, "SerialNumber", udev->serial); /* * OTG-aware devices on OTG-capable root hubs may be able to use SRP, * to wake us after we've powered off VBUS; and HNP, switching roles * "host" to "peripheral". The OTG descriptor helps figure this out. */ if (!udev->bus->is_b_host && udev->config && udev->parent == udev->bus->root_hub) { struct usb_otg_descriptor *desc = 0; struct usb_bus *bus = udev->bus; /* descriptor may appear anywhere in config */ if (__usb_get_extra_descriptor (udev->rawdescriptors[0], le16_to_cpu(udev->config[0].desc.wTotalLength), USB_DT_OTG, (void **) &desc) == 0) { if (desc->bmAttributes & USB_OTG_HNP) { unsigned port1 = udev->portnum; dev_info(&udev->dev, "Dual-Role OTG device on %sHNP port\n", (port1 == bus->otg_port) ? "" : "non-"); /* enable HNP before suspend, it's simpler */ if (port1 == bus->otg_port) bus->b_hnp_enable = 1; err = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), USB_REQ_SET_FEATURE, 0, bus->b_hnp_enable ? USB_DEVICE_B_HNP_ENABLE : USB_DEVICE_A_ALT_HNP_SUPPORT, 0, NULL, 0, USB_CTRL_SET_TIMEOUT); if (err < 0) { /* OTG MESSAGE: report errors here, * customize to match your product. */ dev_info(&udev->dev, "can't set HNP mode; %d\n", err); bus->b_hnp_enable = 0; } } } } if (!is_targeted(udev)) { /* Maybe it can talk to us, though we can't talk to it. * (Includes HNP test device.) */ if (udev->bus->b_hnp_enable || udev->bus->is_b_host) { err = __usb_port_suspend(udev, udev->bus->otg_port); if (err < 0) dev_dbg(&udev->dev, "HNP fail, %d\n", err); } err = -ENODEV; goto fail; } /* export the usbdev device-node for libusb */ udev->dev.devt = MKDEV(USB_DEVICE_MAJOR, (((udev->bus->busnum-1) * 128) + (udev->devnum-1))); /* Increment the parent's count of unsuspended children */ if (udev->parent) usb_autoresume_device(udev->parent); /* Register the device. The device driver is responsible * for adding the device files to sysfs and for configuring * the device. */ err = device_add(&udev->dev); if (err) { dev_err(&udev->dev, "can't device_add, error %d\n", err); if (udev->parent) usb_autosuspend_device(udev->parent); goto fail; }exit: return err;fail: usb_set_device_state(udev, USB_STATE_NOTATTACHED); goto exit;}static int hub_port_status(struct usb_hub *hub, int port1, u16 *status, u16 *change){ int ret; mutex_lock(&hub->status_mutex); ret = get_port_status(hub->hdev, port1, &hub->status->port); if (ret < 4) { dev_err (hub->intfdev, "%s failed (err = %d)\n", __FUNCTION__, ret); if (ret >= 0) ret = -EIO; } else { *status = le16_to_cpu(hub->status->port.wPortStatus); *change = le16_to_cpu(hub->status->port.wPortChange); ret = 0; } mutex_unlock(&hub->status_mutex); return ret;}
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