/* * USB hub driver. * * (C) Copyright 1999 Linus Torvalds * (C) Copyright 1999 Johannes Erdfelt * (C) Copyright 1999 Gregory P. Smith * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au) * */ #include #ifdef CONFIG_USB_DEBUG #define DEBUG #else #undef DEBUG #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "usb.h" #include "hcd.h" #include "hub.h" /* Protect struct usb_device->state and ->children members * Note: Both are also protected by ->serialize, except that ->state can * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */ static DEFINE_SPINLOCK(device_state_lock); /* khubd's worklist and its lock */ static DEFINE_SPINLOCK(hub_event_lock); static LIST_HEAD(hub_event_list); /* List of hubs needing servicing */ /* Wakes up khubd */ static DECLARE_WAIT_QUEUE_HEAD(khubd_wait); static struct task_struct *khubd_task; /* cycle leds on hubs that aren't blinking for attention */ static int blinkenlights = 0; module_param (blinkenlights, bool, S_IRUGO); MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs"); /* * As of 2.6.10 we introduce a new USB device initialization scheme which * closely resembles the way Windows works. Hopefully it will be compatible * with a wider range of devices than the old scheme. However some previously * working devices may start giving rise to "device not accepting address" * errors; if that happens the user can try the old scheme by adjusting the * following module parameters. * * For maximum flexibility there are two boolean parameters to control the * hub driver's behavior. On the first initialization attempt, if the * "old_scheme_first" parameter is set then the old scheme will be used, * otherwise the new scheme is used. If that fails and "use_both_schemes" * is set, then the driver will make another attempt, using the other scheme. */ static int old_scheme_first = 0; module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(old_scheme_first, "start with the old device initialization scheme"); static int use_both_schemes = 1; module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(use_both_schemes, "try the other device initialization scheme if the " "first one fails"); #ifdef DEBUG static inline char *portspeed (int portstatus) { if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED)) return "480 Mb/s"; else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED)) return "1.5 Mb/s"; else return "12 Mb/s"; } #endif /* Note that hdev or one of its children must be locked! */ static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev) { return usb_get_intfdata(hdev->actconfig->interface[0]); } /* USB 2.0 spec Section 11.24.4.5 */ static int get_hub_descriptor(struct usb_device *hdev, void *data, int size) { int i, ret; for (i = 0; i < 3; i++) { ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0), USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB, USB_DT_HUB << 8, 0, data, size, USB_CTRL_GET_TIMEOUT); if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2)) return ret; } return -EINVAL; } /* * USB 2.0 spec Section 11.24.2.1 */ static int clear_hub_feature(struct usb_device *hdev, int feature) { return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0), USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000); } /* * USB 2.0 spec Section 11.24.2.2 */ static int clear_port_feature(struct usb_device *hdev, int port1, int feature) { return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0), USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1, NULL, 0, 1000); } /* * USB 2.0 spec Section 11.24.2.13 */ static int set_port_feature(struct usb_device *hdev, int port1, int feature) { return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0), USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1, NULL, 0, 1000); } /* * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7 * for info about using port indicators */ static void set_port_led( struct usb_hub *hub, int port1, int selector ) { int status = set_port_feature(hub->hdev, (selector << 8) | port1, USB_PORT_FEAT_INDICATOR); if (status < 0) dev_dbg (hub->intfdev, "port %d indicator %s status %d\n", port1, ({ char *s; switch (selector) { case HUB_LED_AMBER: s = "amber"; break; case HUB_LED_GREEN: s = "green"; break; case HUB_LED_OFF: s = "off"; break; case HUB_LED_AUTO: s = "auto"; break; default: s = "??"; break; }; s; }), status); } #define LED_CYCLE_PERIOD ((2*HZ)/3) static void led_work (void *__hub) { struct usb_hub *hub = __hub; struct usb_device *hdev = hub->hdev; unsigned i; unsigned changed = 0; int cursor = -1; if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing) return; for (i = 0; i < hub->descriptor->bNbrPorts; i++) { unsigned selector, mode; /* 30%-50% duty cycle */ switch (hub->indicator[i]) { /* cycle marker */ case INDICATOR_CYCLE: cursor = i; selector = HUB_LED_AUTO; mode = INDICATOR_AUTO; break; /* blinking green = sw attention */ case INDICATOR_GREEN_BLINK: selector = HUB_LED_GREEN; mode = INDICATOR_GREEN_BLINK_OFF; break; case INDICATOR_GREEN_BLINK_OFF: selector = HUB_LED_OFF; mode = INDICATOR_GREEN_BLINK; break; /* blinking amber = hw attention */ case INDICATOR_AMBER_BLINK: selector = HUB_LED_AMBER; mode = INDICATOR_AMBER_BLINK_OFF; break; case INDICATOR_AMBER_BLINK_OFF: selector = HUB_LED_OFF; mode = INDICATOR_AMBER_BLINK; break; /* blink green/amber = reserved */ case INDICATOR_ALT_BLINK: selector = HUB_LED_GREEN; mode = INDICATOR_ALT_BLINK_OFF; break; case INDICATOR_ALT_BLINK_OFF: selector = HUB_LED_AMBER; mode = INDICATOR_ALT_BLINK; break; default: continue; } if (selector != HUB_LED_AUTO) changed = 1; set_port_led(hub, i + 1, selector); hub->indicator[i] = mode; } if (!changed && blinkenlights) { cursor++; cursor %= hub->descriptor->bNbrPorts; set_port_led(hub, cursor + 1, HUB_LED_GREEN); hub->indicator[cursor] = INDICATOR_CYCLE; changed++; } if (changed) schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD); } /* use a short timeout for hub/port status fetches */ #define USB_STS_TIMEOUT 1000 #define USB_STS_RETRIES 5 /* * USB 2.0 spec Section 11.24.2.6 */ static int get_hub_status(struct usb_device *hdev, struct usb_hub_status *data) { int i, status = -ETIMEDOUT; for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) { status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0), USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0, data, sizeof(*data), USB_STS_TIMEOUT); } return status; } /* * USB 2.0 spec Section 11.24.2.7 */ static int get_port_status(struct usb_device *hdev, int port1, struct usb_port_status *data) { int i, status = -ETIMEDOUT; for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) { status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0), USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1, data, sizeof(*data), USB_STS_TIMEOUT); } return status; } static void kick_khubd(struct usb_hub *hub) { unsigned long flags; spin_lock_irqsave(&hub_event_lock, flags); if (list_empty(&hub->event_list)) { list_add_tail(&hub->event_list, &hub_event_list); wake_up(&khubd_wait); } spin_unlock_irqrestore(&hub_event_lock, flags); } void usb_kick_khubd(struct usb_device *hdev) { kick_khubd(hdev_to_hub(hdev)); } /* completion function, fires on port status changes and various faults */ static void hub_irq(struct urb *urb, struct pt_regs *regs) { struct usb_hub *hub = (struct usb_hub *)urb->context; int status; int i; unsigned long bits; switch (urb->status) { case -ENOENT: /* synchronous unlink */ case -ECONNRESET: /* async unlink */ case -ESHUTDOWN: /* hardware going away */ return; default: /* presumably an error */ /* Cause a hub reset after 10 consecutive errors */ dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status); if ((++hub->nerrors < 10) || hub->error) goto resubmit; hub->error = urb->status; /* FALL THROUGH */ /* let khubd handle things */ case 0: /* we got data: port status changed */ bits = 0; for (i = 0; i < urb->actual_length; ++i) bits |= ((unsigned long) ((*hub->buffer)[i])) << (i*8); hub->event_bits[0] = bits; break; } hub->nerrors = 0; /* Something happened, let khubd figure it out */ kick_khubd(hub); resubmit: if (hub->quiescing) return; if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0 && status != -ENODEV && status != -EPERM) dev_err (hub->intfdev, "resubmit --> %d\n", status); } /* USB 2.0 spec Section 11.24.2.3 */ static inline int hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt) { return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0), HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo, tt, NULL, 0, 1000); } /* * enumeration blocks khubd for a long time. we use keventd instead, since * long blocking there is the exception, not the rule. accordingly, HCDs * talking to TTs must queue control transfers (not just bulk and iso), so * both can talk to the same hub concurrently. */ static void hub_tt_kevent (void *arg) { struct usb_hub *hub = arg; unsigned long flags; spin_lock_irqsave (&hub->tt.lock, flags); while (!list_empty (&hub->tt.clear_list)) { struct list_head *temp; struct usb_tt_clear *clear; struct usb_device *hdev = hub->hdev; int status; temp = hub->tt.clear_list.next; clear = list_entry (temp, struct usb_tt_clear, clear_list); list_del (&clear->clear_list); /* drop lock so HCD can concurrently report other TT errors */ spin_unlock_irqrestore (&hub->tt.lock, flags); status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt); spin_lock_irqsave (&hub->tt.lock, flags); if (status) dev_err (&hdev->dev, "clear tt %d (%04x) error %d\n", clear->tt, clear->devinfo, status); kfree(clear); } spin_unlock_irqrestore (&hub->tt.lock, flags); } /** * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub * @udev: the device whose split transaction failed * @pipe: identifies the endpoint of the failed transaction * * High speed HCDs use this to tell the hub driver that some split control or * bulk transaction failed in a way that requires clearing internal state of * a transaction translator. This is normally detected (and reported) from * interrupt context. * * It may not be possible for that hub to handle additional full (or low) * speed transactions until that state is fully cleared out. */ void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe) { struct usb_tt *tt = udev->tt; unsigned long flags; struct usb_tt_clear *clear; /* we've got to cope with an arbitrary number of pending TT clears, * since each TT has "at least two" buffers that can need it (and * there can be many TTs per hub). even if they're uncommon. */ if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) { dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n"); /* FIXME recover somehow ... RESET_TT? */ return; } /* info that CLEAR_TT_BUFFER needs */ clear->tt = tt->multi ? udev->ttport : 1; clear->devinfo = usb_pipeendpoint (pipe); clear->devinfo |= udev->devnum << 4; clear->devinfo |= usb_pipecontrol (pipe) ? (USB_ENDPOINT_XFER_CONTROL << 11) : (USB_ENDPOINT_XFER_BULK << 11); if (usb_pipein (pipe)) clear->devinfo |= 1 << 15; /* tell keventd to clear state for this TT */ spin_lock_irqsave (&tt->lock, flags); list_add_tail (&clear->clear_list, &tt->clear_list); schedule_work (&tt->kevent); spin_unlock_irqrestore (&tt->lock, flags); } static void hub_power_on(struct usb_hub *hub) { int port1; unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2; /* if hub supports power switching, enable power on each port */ if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) < 2) { dev_dbg(hub->intfdev, "enabling power on all ports\n"); for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++) set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER); } /* Wait at least 100 msec for power to become stable */ msleep(max(pgood_delay, (unsigned) 100)); } static void hub_quiesce(struct usb_hub *hub) { /* stop khubd and related activity */ hub->quiescing = 1; hub->activating = 0; usb_kill_urb(hub->urb); if (hub->has_indicators) cancel_delayed_work(&hub->leds); if (hub->has_indicators || hub->tt.hub) flush_scheduled_work(); } static void hub_activate(struct usb_hub *hub) { int status; hub->quiescing = 0; hub->activating = 1; status = usb_submit_urb(hub->urb, GFP_NOIO); if (status < 0) dev_err(hub->intfdev, "activate --> %d\n", status); if (hub->has_indicators && blinkenlights) schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD); /* scan all ports ASAP */ kick_khubd(hub); } static int hub_hub_status(struct usb_hub *hub, u16 *status, u16 *change) { int ret; ret = get_hub_status(hub->hdev, &hub->status->hub); if (ret < 0) dev_err (hub->intfdev, "%s failed (err = %d)\n", __FUNCTION__, ret); else { *status = le16_to_cpu(hub->status->hub.wHubStatus); *change = le16_to_cpu(hub->status->hub.wHubChange); ret = 0; } return ret; } static int hub_port_disable(struct usb_hub *hub, int port1, int set_state) { struct usb_device *hdev = hub->hdev; int ret; if (hdev->children[port1-1] && set_state) { usb_set_device_state(hdev->children[port1-1], USB_STATE_NOTATTACHED); } ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE); if (ret) dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n", port1, ret); return ret; } static int hub_configure(struct usb_hub *hub, struct usb_endpoint_descriptor *endpoint) { struct usb_device *hdev = hub->hdev; struct device *hub_dev = hub->intfdev; u16 hubstatus, hubchange; unsigned int pipe; int maxp, ret; char *message; hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL, &hub->buffer_dma); if (!hub->buffer) { message = "can't allocate hub irq buffer"; ret = -ENOMEM; goto fail; } hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL); if (!hub->status) { message = "can't kmalloc hub status buffer"; ret = -ENOMEM; goto fail; } hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL); if (!hub->descriptor) { message = "can't kmalloc hub descriptor"; ret = -ENOMEM; goto fail; } /* Request the entire hub descriptor. * hub->descriptor can handle USB_MAXCHILDREN ports, * but the hub can/will return fewer bytes here. */ ret = get_hub_descriptor(hdev, hub->descriptor, sizeof(*hub->descriptor)); if (ret < 0) { message = "can't read hub descriptor"; goto fail; } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) { message = "hub has too many ports!"; ret = -ENODEV; goto fail; } hdev->maxchild = hub->descriptor->bNbrPorts; dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild, (hdev->maxchild == 1) ? "" : "s"); le16_to_cpus(&hub->descriptor->wHubCharacteristics); if (hub->descriptor->wHubCharacteristics & HUB_CHAR_COMPOUND) { int i; char portstr [USB_MAXCHILDREN + 1]; for (i = 0; i < hdev->maxchild; i++) portstr[i] = hub->descriptor->DeviceRemovable [((i + 1) / 8)] & (1 << ((i + 1) % 8)) ? 'F' : 'R'; portstr[hdev->maxchild] = 0; dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr); } else dev_dbg(hub_dev, "standalone hub\n"); switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) { case 0x00: dev_dbg(hub_dev, "ganged power switching\n"); break; case 0x01: dev_dbg(hub_dev, "individual port power switching\n"); break; case 0x02: case 0x03: dev_dbg(hub_dev, "no power switching (usb 1.0)\n"); break; } switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) { case 0x00: dev_dbg(hub_dev, "global over-current protection\n"); break; case 0x08: dev_dbg(hub_dev, "individual port over-current protection\n"); break; case 0x10: case 0x18: dev_dbg(hub_dev, "no over-current protection\n"); break; } spin_lock_init (&hub->tt.lock); INIT_LIST_HEAD (&hub->tt.clear_list); INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub); switch (hdev->descriptor.bDeviceProtocol) { case 0: break; case 1: dev_dbg(hub_dev, "Single TT\n"); hub->tt.hub = hdev; break; case 2: ret = usb_set_interface(hdev, 0, 1); if (ret == 0) { dev_dbg(hub_dev, "TT per port\n"); hub->tt.multi = 1; } else dev_err(hub_dev, "Using single TT (err %d)\n", ret); hub->tt.hub = hdev; break; default: dev_dbg(hub_dev, "Unrecognized hub protocol %d\n", hdev->descriptor.bDeviceProtocol); break; } /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */ switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) { case HUB_TTTT_8_BITS: if (hdev->descriptor.bDeviceProtocol != 0) { hub->tt.think_time = 666; dev_dbg(hub_dev, "TT requires at most %d " "FS bit times (%d ns)\n", 8, hub->tt.think_time); } break; case HUB_TTTT_16_BITS: hub->tt.think_time = 666 * 2; dev_dbg(hub_dev, "TT requires at most %d " "FS bit times (%d ns)\n", 16, hub->tt.think_time); break; case HUB_TTTT_24_BITS: hub->tt.think_time = 666 * 3; dev_dbg(hub_dev, "TT requires at most %d " "FS bit times (%d ns)\n", 24, hub->tt.think_time); break; case HUB_TTTT_32_BITS: hub->tt.think_time = 666 * 4; dev_dbg(hub_dev, "TT requires at most %d " "FS bit times (%d ns)\n", 32, hub->tt.think_time); break; } /* probe() zeroes hub->indicator[] */ if (hub->descriptor->wHubCharacteristics & HUB_CHAR_PORTIND) { hub->has_indicators = 1; dev_dbg(hub_dev, "Port indicators are supported\n"); } dev_dbg(hub_dev, "power on to power good time: %dms\n", hub->descriptor->bPwrOn2PwrGood * 2); /* power budgeting mostly matters with bus-powered hubs, * and battery-powered root hubs (may provide just 8 mA). */ ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus); if (ret < 0) { message = "can't get hub status"; goto fail; } le16_to_cpus(&hubstatus); if (hdev == hdev->bus->root_hub) { struct usb_hcd *hcd = container_of(hdev->bus, struct usb_hcd, self); hub->power_budget = min(500u, hcd->power_budget) / 2; } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) { dev_dbg(hub_dev, "hub controller current requirement: %dmA\n", hub->descriptor->bHubContrCurrent); hub->power_budget = (501 - hub->descriptor->bHubContrCurrent) / 2; } if (hub->power_budget) dev_dbg(hub_dev, "%dmA bus power budget for children\n", hub->power_budget * 2); ret = hub_hub_status(hub, &hubstatus, &hubchange); if (ret < 0) { message = "can't get hub status"; goto fail; } /* local power status reports aren't always correct */ if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER) dev_dbg(hub_dev, "local power source is %s\n", (hubstatus & HUB_STATUS_LOCAL_POWER) ? "lost (inactive)" : "good"); if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_OCPM) == 0) dev_dbg(hub_dev, "%sover-current condition exists\n", (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no "); /* set up the interrupt endpoint */ pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress); maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe)); if (maxp > sizeof(*hub->buffer)) maxp = sizeof(*hub->buffer); hub->urb = usb_alloc_urb(0, GFP_KERNEL); if (!hub->urb) { message = "couldn't allocate interrupt urb"; ret = -ENOMEM; goto fail; } usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq, hub, endpoint->bInterval); hub->urb->transfer_dma = hub->buffer_dma; hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; /* maybe cycle the hub leds */ if (hub->has_indicators && blinkenlights) hub->indicator [0] = INDICATOR_CYCLE; hub_power_on(hub); hub_activate(hub); return 0; fail: dev_err (hub_dev, "config failed, %s (err %d)\n", message, ret); /* hub_disconnect() frees urb and descriptor */ return ret; } static unsigned highspeed_hubs; /* Called after the hub driver is unbound from a hub with children */ static void hub_remove_children_work(void *__hub) { struct usb_hub *hub = __hub; struct usb_device *hdev = hub->hdev; int i; kfree(hub); usb_lock_device(hdev); for (i = 0; i < hdev->maxchild; ++i) { if (hdev->children[i]) usb_disconnect(&hdev->children[i]); } usb_unlock_device(hdev); usb_put_dev(hdev); } static void hub_disconnect(struct usb_interface *intf) { struct usb_hub *hub = usb_get_intfdata (intf); struct usb_device *hdev; int n, port1; usb_set_intfdata (intf, NULL); hdev = hub->hdev; if (hdev->speed == USB_SPEED_HIGH) highspeed_hubs--; hub_quiesce(hub); usb_free_urb(hub->urb); hub->urb = NULL; spin_lock_irq(&hub_event_lock); list_del_init(&hub->event_list); spin_unlock_irq(&hub_event_lock); kfree(hub->descriptor); hub->descriptor = NULL; kfree(hub->status); hub->status = NULL; if (hub->buffer) { usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer, hub->buffer_dma); hub->buffer = NULL; } /* If there are any children then this is an unbind only, not a * physical disconnection. The active ports must be disabled * and later on we must call usb_disconnect(). We can't call * it now because we may not hold the hub's device lock. */ n = 0; for (port1 = 1; port1 <= hdev->maxchild; ++port1) { if (hdev->children[port1 - 1]) { ++n; hub_port_disable(hub, port1, 1); } } if (n == 0) kfree(hub); else { /* Reuse the hub->leds work_struct for our own purposes */ INIT_WORK(&hub->leds, hub_remove_children_work, hub); schedule_work(&hub->leds); usb_get_dev(hdev); } } static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id) { struct usb_host_interface *desc; struct usb_endpoint_descriptor *endpoint; struct usb_device *hdev; struct usb_hub *hub; desc = intf->cur_altsetting; hdev = interface_to_usbdev(intf); /* Some hubs have a subclass of 1, which AFAICT according to the */ /* specs is not defined, but it works */ if ((desc->desc.bInterfaceSubClass != 0) && (desc->desc.bInterfaceSubClass != 1)) { descriptor_error: dev_err (&intf->dev, "bad descriptor, ignoring hub\n"); return -EIO; } /* Multiple endpoints? What kind of mutant ninja-hub is this? */ if (desc->desc.bNumEndpoints != 1) goto descriptor_error; endpoint = &desc->endpoint[0].desc; /* Output endpoint? Curiouser and curiouser.. */ if (!(endpoint->bEndpointAddress & USB_DIR_IN)) goto descriptor_error; /* If it's not an interrupt endpoint, we'd better punt! */ if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_INT) goto descriptor_error; /* We found a hub */ dev_info (&intf->dev, "USB hub found\n"); hub = kmalloc(sizeof(*hub), GFP_KERNEL); if (!hub) { dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n"); return -ENOMEM; } memset(hub, 0, sizeof(*hub)); INIT_LIST_HEAD(&hub->event_list); hub->intfdev = &intf->dev; hub->hdev = hdev; INIT_WORK(&hub->leds, led_work, hub); usb_set_intfdata (intf, hub); if (hdev->speed == USB_SPEED_HIGH) highspeed_hubs++; if (hub_configure(hub, endpoint) >= 0) return 0; hub_disconnect (intf); return -ENODEV; } static int hub_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; } } /* caller has locked the hub device */ static void hub_pre_reset(struct usb_hub *hub) { struct usb_device *hdev = hub->hdev; int i; for (i = 0; i < hdev->maxchild; ++i) { if (hdev->children[i]) usb_disconnect(&hdev->children[i]); } hub_quiesce(hub); } /* caller has locked the hub device */ static void hub_post_reset(struct usb_hub *hub) { hub_activate(hub); hub_power_on(hub); } /* 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; for (t = 0; t < hdev->maxchild; t++) { if (hdev->children[t] == udev) { /* everything is fail-fast once disconnect * processing starts */ if (udev->state == USB_STATE_NOTATTACHED) break; /* when everyone grabs locks top->bottom, * non-overlapping work may be concurrent */ down(&udev->serialize); up(&hdev->serialize); return t + 1; } } usb_unlock_device(hdev); return -ENODEV; } 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]); } 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) { udev->state = new_state; if (new_state == USB_STATE_CONFIGURED) device_init_wakeup(&udev->dev, (udev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_WAKEUP)); else if (new_state != USB_STATE_SUSPENDED) device_init_wakeup(&udev->dev, 0); } else recursively_mark_NOTATTACHED(udev); spin_unlock_irqrestore(&device_state_lock, flags); } EXPORT_SYMBOL(usb_set_device_state); 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; } } /** * 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); /* lock the bus list on behalf of HCDs unregistering their root hubs */ if (!udev->parent) { down(&usb_bus_list_lock); usb_lock_device(udev); } else down(&udev->serialize); dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum); /* 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. */ usb_disable_device(udev, 0); /* Free the device number, remove the /proc/bus/usb entry and * the sysfs attributes, and delete the parent's children[] * (or root_hub) pointer. */ dev_dbg (&udev->dev, "unregistering device\n"); release_address(udev); usbfs_remove_device(udev); usbdev_remove(udev); usb_remove_sysfs_dev_files(udev); /* Avoid races with recursively_mark_NOTATTACHED() */ spin_lock_irq(&device_state_lock); *pdev = NULL; spin_unlock_irq(&device_state_lock); if (!udev->parent) { usb_unlock_device(udev); up(&usb_bus_list_lock); } else up(&udev->serialize); device_unregister(&udev->dev); } static int choose_configuration(struct usb_device *udev) { int c, i; /* NOTE: this should interact with hub power budgeting */ c = udev->config[0].desc.bConfigurationValue; if (udev->descriptor.bNumConfigurations != 1) { for (i = 0; i < udev->descriptor.bNumConfigurations; i++) { struct usb_interface_descriptor *desc; /* heuristic: Linux is more likely to have class * drivers, so avoid vendor-specific interfaces. */ desc = &udev->config[i].intf_cache[0] ->altsetting->desc; if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC) continue; /* COMM/2/all is CDC ACM, except 0xff is MSFT RNDIS. * MSFT needs this to be the first config; never use * it as the default unless Linux has host-side RNDIS. * A second config would ideally be CDC-Ethernet, but * may instead be the "vendor specific" CDC subset * long used by ARM Linux for sa1100 or pxa255. */ if (desc->bInterfaceClass == USB_CLASS_COMM && desc->bInterfaceSubClass == 2 && desc->bInterfaceProtocol == 0xff) { c = udev->config[1].desc.bConfigurationValue; continue; } c = udev->config[i].desc.bConfigurationValue; break; } dev_info(&udev->dev, "configuration #%d chosen from %d choices\n", c, udev->descriptor.bNumConfigurations); } return c; } #ifdef DEBUG static void show_string(struct usb_device *udev, char *id, char *string) { if (!string) return; dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string); } #else static inline void show_string(struct usb_device *udev, char *id, char *string) {} #endif static void get_string(struct usb_device *udev, char **string, int index) { char *buf; if (!index) return; buf = kmalloc(256, GFP_KERNEL); if (!buf) return; if (usb_string(udev, index, buf, 256) > 0) *string = buf; else kfree(buf); } #ifdef CONFIG_USB_OTG #include "otg_whitelist.h" #endif /** * 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 udev and * 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. * * Returns 0 for success (device is configured and listed, with its * interfaces, in sysfs); else a negative errno value. * * This call is synchronous, and may not be used in an interrupt context. * * Only the hub driver should ever call this; root hub registration * uses it indirectly. */ int usb_new_device(struct usb_device *udev) { int err; int c; 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 */ get_string(udev, &udev->product, udev->descriptor.iProduct); get_string(udev, &udev->manufacturer, udev->descriptor.iManufacturer); get_string(udev, &udev->serial, 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); #ifdef CONFIG_USB_OTG /* * 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; struct usb_device *root = udev->parent; for (port1 = 1; port1 <= root->maxchild; port1++) { if (root->children[port1-1] == udev) break; } 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) { static int __usb_suspend_device(struct usb_device *, int port1); err = __usb_suspend_device(udev, udev->bus->otg_port); if (err < 0) dev_dbg(&udev->dev, "HNP fail, %d\n", err); } err = -ENODEV; goto fail; } #endif /* put device-specific files into sysfs */ err = device_add (&udev->dev); if (err) { dev_err(&udev->dev, "can't device_add, error %d\n", err); goto fail; } usb_create_sysfs_dev_files (udev); /* choose and set the configuration. that registers the interfaces * with the driver core, and lets usb device drivers bind to them. */ c = choose_configuration(udev); if (c < 0) dev_warn(&udev->dev, "can't choose an initial configuration\n"); else { err = usb_set_configuration(udev, c); if (err) { dev_err(&udev->dev, "can't set config #%d, error %d\n", c, err); usb_remove_sysfs_dev_files(udev); device_del(&udev->dev); goto fail; } } /* USB device state == configured ... usable */ /* add a /proc/bus/usb entry */ usbdev_add(udev); usbfs_add_device(udev); return 0; fail: usb_set_device_state(udev, USB_STATE_NOTATTACHED); return err; } static int hub_port_status(struct usb_hub *hub, int port1, u16 *status, u16 *change) { int ret; ret = get_port_status(hub->hdev, port1, &hub->status->port); if (ret < 0) dev_err (hub->intfdev, "%s failed (err = %d)\n", __FUNCTION__, ret); else { *status = le16_to_cpu(hub->status->port.wPortStatus); *change = le16_to_cpu(hub->status->port.wPortChange); ret = 0; } return ret; } #define PORT_RESET_TRIES 5 #define SET_ADDRESS_TRIES 2 #define GET_DESCRIPTOR_TRIES 2 #define SET_CONFIG_TRIES (2 * (use_both_schemes + 1)) #define USE_NEW_SCHEME(i) ((i) / 2 == old_scheme_first) #define HUB_ROOT_RESET_TIME 50 /* times are in msec */ #define HUB_SHORT_RESET_TIME 10 #define HUB_LONG_RESET_TIME 200 #define HUB_RESET_TIMEOUT 500 static int hub_port_wait_reset(struct usb_hub *hub, int port1, struct usb_device *udev, unsigned int delay) { int delay_time, ret; u16 portstatus; u16 portchange; for (delay_time = 0; delay_time < HUB_RESET_TIMEOUT; delay_time += delay) { /* wait to give the device a chance to reset */ msleep(delay); /* read and decode port status */ ret = hub_port_status(hub, port1, &portstatus, &portchange); if (ret < 0) return ret; /* Device went away? */ if (!(portstatus & USB_PORT_STAT_CONNECTION)) return -ENOTCONN; /* bomb out completely if something weird happened */ if ((portchange & USB_PORT_STAT_C_CONNECTION)) return -EINVAL; /* if we`ve finished resetting, then break out of the loop */ if (!(portstatus & USB_PORT_STAT_RESET) && (portstatus & USB_PORT_STAT_ENABLE)) { if (portstatus & USB_PORT_STAT_HIGH_SPEED) udev->speed = USB_SPEED_HIGH; else if (portstatus & USB_PORT_STAT_LOW_SPEED) udev->speed = USB_SPEED_LOW; else udev->speed = USB_SPEED_FULL; return 0; } /* switch to the long delay after two short delay failures */ if (delay_time >= 2 * HUB_SHORT_RESET_TIME) delay = HUB_LONG_RESET_TIME; dev_dbg (hub->intfdev, "port %d not reset yet, waiting %dms\n", port1, delay); } return -EBUSY; } static int hub_port_reset(struct usb_hub *hub, int port1, struct usb_device *udev, unsigned int delay) { int i, status; /* Reset the port */ for (i = 0; i < PORT_RESET_TRIES; i++) { status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_RESET); if (status) dev_err(hub->intfdev, "cannot reset port %d (err = %d)\n", port1, status); else { status = hub_port_wait_reset(hub, port1, udev, delay); if (status && status != -ENOTCONN) dev_dbg(hub->intfdev, "port_wait_reset: err = %d\n", status); } /* return on disconnect or reset */ switch (status) { case 0: /* TRSTRCY = 10 ms; plus some extra */ msleep(10 + 40); /* FALL THROUGH */ case -ENOTCONN: case -ENODEV: clear_port_feature(hub->hdev, port1, USB_PORT_FEAT_C_RESET); /* FIXME need disconnect() for NOTATTACHED device */ usb_set_device_state(udev, status ? USB_STATE_NOTATTACHED : USB_STATE_DEFAULT); return status; } dev_dbg (hub->intfdev, "port %d not enabled, trying reset again...\n", port1); delay = HUB_LONG_RESET_TIME; } dev_err (hub->intfdev, "Cannot enable port %i. Maybe the USB cable is bad?\n", port1); return status; } /* * Disable a port and mark a logical connnect-change event, so that some * time later khubd will disconnect() any existing usb_device on the port * and will re-enumerate if there actually is a device attached. */ static void hub_port_logical_disconnect(struct usb_hub *hub, int port1) { dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1); hub_port_disable(hub, port1, 1); /* FIXME let caller ask to power down the port: * - some devices won't enumerate without a VBUS power cycle * - SRP saves power that way * - ... new call, TBD ... * That's easy if this hub can switch power per-port, and * khubd reactivates the port later (timer, SRP, etc). * Powerdown must be optional, because of reset/DFU. */ set_bit(port1, hub->change_bits); kick_khubd(hub); } #ifdef CONFIG_USB_SUSPEND /* * Selective port suspend reduces power; most suspended devices draw * less than 500 uA. It's also used in OTG, along with remote wakeup. * All devices below the suspended port are also suspended. * * Devices leave suspend state when the host wakes them up. Some devices * also support "remote wakeup", where the device can activate the USB * tree above them to deliver data, such as a keypress or packet. In * some cases, this wakes the USB host. */ static int hub_port_suspend(struct usb_hub *hub, int port1, struct usb_device *udev) { int status; // dev_dbg(hub->intfdev, "suspend port %d\n", port1); /* enable remote wakeup when appropriate; this lets the device * wake up the upstream hub (including maybe the root hub). * * NOTE: OTG devices may issue remote wakeup (or SRP) even when * we don't explicitly enable it here. */ if (device_may_wakeup(&udev->dev)) { status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), USB_REQ_SET_FEATURE, USB_RECIP_DEVICE, USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0, USB_CTRL_SET_TIMEOUT); if (status) dev_dbg(&udev->dev, "won't remote wakeup, status %d\n", status); } /* see 7.1.7.6 */ status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND); if (status) { dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n", port1, status); /* paranoia: "should not happen" */ (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0), USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE, USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0, USB_CTRL_SET_TIMEOUT); } else { /* device has up to 10 msec to fully suspend */ dev_dbg(&udev->dev, "usb suspend\n"); usb_set_device_state(udev, USB_STATE_SUSPENDED); msleep(10); } return status; } /* * Devices on USB hub ports have only one "suspend" state, corresponding * to ACPI D2, "may cause the device to lose some context". * State transitions include: * * - suspend, resume ... when the VBUS power link stays live * - suspend, disconnect ... VBUS lost * * Once VBUS drop breaks the circuit, the port it's using has to go through * normal re-enumeration procedures, starting with enabling VBUS power. * Other than re-initializing the hub (plug/unplug, except for root hubs), * Linux (2.6) currently has NO mechanisms to initiate that: no khubd * timer, no SRP, no requests through sysfs. * * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when * the root hub for their bus goes into global suspend ... so we don't * (falsely) update the device power state to say it suspended. */ static int __usb_suspend_device (struct usb_device *udev, int port1) { int status; /* caller owns the udev device lock */ if (port1 < 0) return port1; if (udev->state == USB_STATE_SUSPENDED || udev->state == USB_STATE_NOTATTACHED) { return 0; } /* all interfaces must already be suspended */ if (udev->actconfig) { int i; for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { struct usb_interface *intf; intf = udev->actconfig->interface[i]; if (is_active(intf)) { dev_dbg(&intf->dev, "nyet suspended\n"); return -EBUSY; } } } /* "global suspend" of the HC-to-USB interface (root hub), or * "selective suspend" of just one hub-device link. */ if (!udev->parent) { struct usb_bus *bus = udev->bus; if (bus && bus->op->hub_suspend) { status = bus->op->hub_suspend (bus); if (status == 0) { dev_dbg(&udev->dev, "usb suspend\n"); usb_set_device_state(udev, USB_STATE_SUSPENDED); } } else status = -EOPNOTSUPP; } else status = hub_port_suspend(hdev_to_hub(udev->parent), port1, udev); if (status == 0) udev->dev.power.power_state = PMSG_SUSPEND; return status; } /** * usb_suspend_device - suspend a usb device * @udev: device that's no longer in active use * Context: must be able to sleep; device not locked * * Suspends a USB device that isn't in active use, conserving power. * Devices may wake out of a suspend, if anything important happens, * using the remote wakeup mechanism. They may also be taken out of * suspend by the host, using usb_resume_device(). It's also routine * to disconnect devices while they are suspended. * * This only affects the USB hardware for a device; its interfaces * (and, for hubs, child devices) must already have been suspended. * * Suspending OTG devices may trigger HNP, if that's been enabled * between a pair of dual-role devices. That will change roles, such * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral. * * Returns 0 on success, else negative errno. */ int usb_suspend_device(struct usb_device *udev) { int port1, status; port1 = locktree(udev); if (port1 < 0) return port1; status = __usb_suspend_device(udev, port1); usb_unlock_device(udev); return status; } /* * If the USB "suspend" state is in use (rather than "global suspend"), * many devices will be individually taken out of suspend state using * special" resume" signaling. These routines kick in shortly after * hardware resume signaling is finished, either because of selective * resume (by host) or remote wakeup (by device) ... now see what changed * in the tree that's rooted at this device. */ static int finish_port_resume(struct usb_device *udev) { int status; u16 devstatus; /* caller owns the udev device lock */ dev_dbg(&udev->dev, "usb resume\n"); /* usb ch9 identifies four variants of SUSPENDED, based on what * state the device resumes to. Linux currently won't see the * first two on the host side; they'd be inside hub_port_init() * during many timeouts, but khubd can't suspend until later. */ usb_set_device_state(udev, udev->actconfig ? USB_STATE_CONFIGURED : USB_STATE_ADDRESS); udev->dev.power.power_state = PMSG_ON; /* 10.5.4.5 says be sure devices in the tree are still there. * For now let's assume the device didn't go crazy on resume, * and device drivers will know about any resume quirks. */ status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus); if (status < 0) dev_dbg(&udev->dev, "gone after usb resume? status %d\n", status); else if (udev->actconfig) { unsigned i; int (*resume)(struct device *); le16_to_cpus(&devstatus); if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) { status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE, USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0, USB_CTRL_SET_TIMEOUT); if (status) { dev_dbg(&udev->dev, "disable remote " "wakeup, status %d\n", status); status = 0; } } /* resume interface drivers; if this is a hub, it * may have a child resume event to deal with soon */ resume = udev->dev.bus->resume; for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) (void) resume(&udev->actconfig->interface[i]->dev); status = 0; } else if (udev->devnum <= 0) { dev_dbg(&udev->dev, "bogus resume!\n"); status = -EINVAL; } return status; } static int hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev) { int status; // dev_dbg(hub->intfdev, "resume port %d\n", port1); /* see 7.1.7.7; affects power usage, but not budgeting */ status = clear_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND); if (status) { dev_dbg(hub->intfdev, "can't resume port %d, status %d\n", port1, status); } else { u16 devstatus; u16 portchange; /* drive resume for at least 20 msec */ if (udev) dev_dbg(&udev->dev, "RESUME\n"); msleep(25); #define LIVE_FLAGS ( USB_PORT_STAT_POWER \ | USB_PORT_STAT_ENABLE \ | USB_PORT_STAT_CONNECTION) /* Virtual root hubs can trigger on GET_PORT_STATUS to * stop resume signaling. Then finish the resume * sequence. */ devstatus = portchange = 0; status = hub_port_status(hub, port1, &devstatus, &portchange); if (status < 0 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS || (devstatus & USB_PORT_STAT_SUSPEND) != 0 ) { dev_dbg(hub->intfdev, "port %d status %04x.%04x after resume, %d\n", port1, portchange, devstatus, status); } else { /* TRSMRCY = 10 msec */ msleep(10); if (udev) status = finish_port_resume(udev); } } if (status < 0) hub_port_logical_disconnect(hub, port1); return status; } static int hub_resume (struct usb_interface *intf); /** * usb_resume_device - re-activate a suspended usb device * @udev: device to re-activate * Context: must be able to sleep; device not locked * * This will re-activate the suspended device, increasing power usage * while letting drivers communicate again with its endpoints. * USB resume explicitly guarantees that the power session between * the host and the device is the same as it was when the device * suspended. * * Returns 0 on success, else negative errno. */ int usb_resume_device(struct usb_device *udev) { int port1, status; port1 = locktree(udev); if (port1 < 0) return port1; /* "global resume" of the HC-to-USB interface (root hub), or * selective resume of one hub-to-device port */ if (!udev->parent) { struct usb_bus *bus = udev->bus; if (bus && bus->op->hub_resume) { status = bus->op->hub_resume (bus); } else status = -EOPNOTSUPP; if (status == 0) { dev_dbg(&udev->dev, "usb resume\n"); /* TRSMRCY = 10 msec */ msleep(10); usb_set_device_state (udev, USB_STATE_CONFIGURED); udev->dev.power.power_state = PMSG_ON; status = hub_resume (udev ->actconfig->interface[0]); } } else if (udev->state == USB_STATE_SUSPENDED) { // NOTE this fails if parent is also suspended... status = hub_port_resume(hdev_to_hub(udev->parent), port1, udev); } else { status = 0; } if (status < 0) { dev_dbg(&udev->dev, "can't resume, status %d\n", status); } usb_unlock_device(udev); /* rebind drivers that had no suspend() */ if (status == 0) { usb_lock_all_devices(); bus_rescan_devices(&usb_bus_type); usb_unlock_all_devices(); } return status; } static int remote_wakeup(struct usb_device *udev) { int status = 0; /* don't repeat RESUME sequence if this device * was already woken up by some other task */ down(&udev->serialize); if (udev->state == USB_STATE_SUSPENDED) { dev_dbg(&udev->dev, "RESUME (wakeup)\n"); /* TRSMRCY = 10 msec */ msleep(10); status = finish_port_resume(udev); } up(&udev->serialize); return status; } static int hub_suspend(struct usb_interface *intf, pm_message_t msg) { struct usb_hub *hub = usb_get_intfdata (intf); struct usb_device *hdev = hub->hdev; unsigned port1; /* fail if children aren't already suspended */ for (port1 = 1; port1 <= hdev->maxchild; port1++) { struct usb_device *udev; udev = hdev->children [port1-1]; if (udev && udev->state != USB_STATE_SUSPENDED) { dev_dbg(&intf->dev, "port %d nyet suspended\n", port1); return -EBUSY; } } /* stop khubd and related activity */ hub_quiesce(hub); return 0; } static int hub_resume(struct usb_interface *intf) { struct usb_device *hdev = interface_to_usbdev(intf); struct usb_hub *hub = usb_get_intfdata (intf); unsigned port1; int status; for (port1 = 1; port1 <= hdev->maxchild; port1++) { struct usb_device *udev; u16 portstat, portchange; udev = hdev->children [port1-1]; status = hub_port_status(hub, port1, &portstat, &portchange); if (status == 0) { if (portchange & USB_PORT_STAT_C_SUSPEND) { clear_port_feature(hdev, port1, USB_PORT_FEAT_C_SUSPEND); portchange &= ~USB_PORT_STAT_C_SUSPEND; } /* let khubd handle disconnects etc */ if (portchange) continue; } if (!udev || status < 0) continue; down (&udev->serialize); if (portstat & USB_PORT_STAT_SUSPEND) status = hub_port_resume(hub, port1, udev); else { status = finish_port_resume(udev); if (status < 0) { dev_dbg(&intf->dev, "resume port %d --> %d\n", port1, status); hub_port_logical_disconnect(hub, port1); } } up(&udev->serialize); } hub->resume_root_hub = 0; hub_activate(hub); return 0; } void usb_resume_root_hub(struct usb_device *hdev) { struct usb_hub *hub = hdev_to_hub(hdev); hub->resume_root_hub = 1; kick_khubd(hub); } #else /* !CONFIG_USB_SUSPEND */ int usb_suspend_device(struct usb_device *udev) { /* state does NOT lie by saying it's USB_STATE_SUSPENDED! */ return 0; } int usb_resume_device(struct usb_device *udev) { udev->dev.power_state.event = PM_EVENT_ON; return 0; } #define hub_suspend NULL #define hub_resume NULL #define remote_wakeup(x) 0 #endif /* CONFIG_USB_SUSPEND */ EXPORT_SYMBOL(usb_suspend_device); EXPORT_SYMBOL(usb_resume_device); /* USB 2.0 spec, 7.1.7.3 / fig 7-29: * * Between connect detection and reset signaling there must be a delay * of 100ms at least for debounce and power-settling. The corresponding * timer shall restart whenever the downstream port detects a disconnect. * * Apparently there are some bluetooth and irda-dongles and a number of * low-speed devices for which this debounce period may last over a second. * Not covered by the spec - but easy to deal with. * * This implementation uses a 1500ms total debounce timeout; if the * connection isn't stable by then it returns -ETIMEDOUT. It checks * every 25ms for transient disconnects. When the port status has been * unchanged for 100ms it returns the port status. */ #define HUB_DEBOUNCE_TIMEOUT 1500 #define HUB_DEBOUNCE_STEP 25 #define HUB_DEBOUNCE_STABLE 100 static int hub_port_debounce(struct usb_hub *hub, int port1) { int ret; int total_time, stable_time = 0; u16 portchange, portstatus; unsigned connection = 0xffff; for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) { ret = hub_port_status(hub, port1, &portstatus, &portchange); if (ret < 0) return ret; if (!(portchange & USB_PORT_STAT_C_CONNECTION) && (portstatus & USB_PORT_STAT_CONNECTION) == connection) { stable_time += HUB_DEBOUNCE_STEP; if (stable_time >= HUB_DEBOUNCE_STABLE) break; } else { stable_time = 0; connection = portstatus & USB_PORT_STAT_CONNECTION; } if (portchange & USB_PORT_STAT_C_CONNECTION) { clear_port_feature(hub->hdev, port1, USB_PORT_FEAT_C_CONNECTION); } if (total_time >= HUB_DEBOUNCE_TIMEOUT) break; msleep(HUB_DEBOUNCE_STEP); } dev_dbg (hub->intfdev, "debounce: port %d: total %dms stable %dms status 0x%x\n", port1, total_time, stable_time, portstatus); if (stable_time < HUB_DEBOUNCE_STABLE) return -ETIMEDOUT; return portstatus; } static void ep0_reinit(struct usb_device *udev) { usb_disable_endpoint(udev, 0 + USB_DIR_IN); usb_disable_endpoint(udev, 0 + USB_DIR_OUT); udev->ep_in[0] = udev->ep_out[0] = &udev->ep0; } #define usb_sndaddr0pipe() (PIPE_CONTROL << 30) #define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN) static int hub_set_address(struct usb_device *udev) { int retval; if (udev->devnum == 0) return -EINVAL; if (udev->state == USB_STATE_ADDRESS) return 0; if (udev->state != USB_STATE_DEFAULT) return -EINVAL; retval = usb_control_msg(udev, usb_sndaddr0pipe(), USB_REQ_SET_ADDRESS, 0, udev->devnum, 0, NULL, 0, USB_CTRL_SET_TIMEOUT); if (retval == 0) { usb_set_device_state(udev, USB_STATE_ADDRESS); ep0_reinit(udev); } return retval; } /* Reset device, (re)assign address, get device descriptor. * Device connection must be stable, no more debouncing needed. * Returns device in USB_STATE_ADDRESS, except on error. * * If this is called for an already-existing device (as part of * usb_reset_device), the caller must own the device lock. For a * newly detected device that is not accessible through any global * pointers, it's not necessary to lock the device. */ static int hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1, int retry_counter) { static DECLARE_MUTEX(usb_address0_sem); struct usb_device *hdev = hub->hdev; int i, j, retval; unsigned delay = HUB_SHORT_RESET_TIME; enum usb_device_speed oldspeed = udev->speed; /* root hub ports have a slightly longer reset period * (from USB 2.0 spec, section 7.1.7.5) */ if (!hdev->parent) { delay = HUB_ROOT_RESET_TIME; if (port1 == hdev->bus->otg_port) hdev->bus->b_hnp_enable = 0; } /* Some low speed devices have problems with the quick delay, so */ /* be a bit pessimistic with those devices. RHbug #23670 */ if (oldspeed == USB_SPEED_LOW) delay = HUB_LONG_RESET_TIME; down(&usb_address0_sem); /* Reset the device; full speed may morph to high speed */ retval = hub_port_reset(hub, port1, udev, delay); if (retval < 0) /* error or disconnect */ goto fail; /* success, speed is known */ retval = -ENODEV; if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) { dev_dbg(&udev->dev, "device reset changed speed!\n"); goto fail; } oldspeed = udev->speed; /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ... * it's fixed size except for full speed devices. */ switch (udev->speed) { case USB_SPEED_HIGH: /* fixed at 64 */ udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64); break; case USB_SPEED_FULL: /* 8, 16, 32, or 64 */ /* to determine the ep0 maxpacket size, try to read * the device descriptor to get bMaxPacketSize0 and * then correct our initial guess. */ udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64); break; case USB_SPEED_LOW: /* fixed at 8 */ udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8); break; default: goto fail; } dev_info (&udev->dev, "%s %s speed USB device using %s and address %d\n", (udev->config) ? "reset" : "new", ({ char *speed; switch (udev->speed) { case USB_SPEED_LOW: speed = "low"; break; case USB_SPEED_FULL: speed = "full"; break; case USB_SPEED_HIGH: speed = "high"; break; default: speed = "?"; break; }; speed;}), udev->bus->controller->driver->name, udev->devnum); /* Set up TT records, if needed */ if (hdev->tt) { udev->tt = hdev->tt; udev->ttport = hdev->ttport; } else if (udev->speed != USB_SPEED_HIGH && hdev->speed == USB_SPEED_HIGH) { udev->tt = &hub->tt; udev->ttport = port1; } /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way? * Because device hardware and firmware is sometimes buggy in * this area, and this is how Linux has done it for ages. * Change it cautiously. * * NOTE: If USE_NEW_SCHEME() is true we will start by issuing * a 64-byte GET_DESCRIPTOR request. This is what Windows does, * so it may help with some non-standards-compliant devices. * Otherwise we start with SET_ADDRESS and then try to read the * first 8 bytes of the device descriptor to get the ep0 maxpacket * value. */ for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) { if (USE_NEW_SCHEME(retry_counter)) { struct usb_device_descriptor *buf; int r = 0; #define GET_DESCRIPTOR_BUFSIZE 64 buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO); if (!buf) { retval = -ENOMEM; continue; } /* Use a short timeout the first time through, * so that recalcitrant full-speed devices with * 8- or 16-byte ep0-maxpackets won't slow things * down tremendously by NAKing the unexpectedly * early status stage. Also, retry on all errors; * some devices are flakey. */ for (j = 0; j < 3; ++j) { buf->bMaxPacketSize0 = 0; r = usb_control_msg(udev, usb_rcvaddr0pipe(), USB_REQ_GET_DESCRIPTOR, USB_DIR_IN, USB_DT_DEVICE << 8, 0, buf, GET_DESCRIPTOR_BUFSIZE, (i ? USB_CTRL_GET_TIMEOUT : 1000)); switch (buf->bMaxPacketSize0) { case 8: case 16: case 32: case 64: if (buf->bDescriptorType == USB_DT_DEVICE) { r = 0; break; } /* FALL THROUGH */ default: if (r == 0) r = -EPROTO; break; } if (r == 0) break; } udev->descriptor.bMaxPacketSize0 = buf->bMaxPacketSize0; kfree(buf); retval = hub_port_reset(hub, port1, udev, delay); if (retval < 0) /* error or disconnect */ goto fail; if (oldspeed != udev->speed) { dev_dbg(&udev->dev, "device reset changed speed!\n"); retval = -ENODEV; goto fail; } if (r) { dev_err(&udev->dev, "device descriptor " "read/%s, error %d\n", "64", r); retval = -EMSGSIZE; continue; } #undef GET_DESCRIPTOR_BUFSIZE } for (j = 0; j < SET_ADDRESS_TRIES; ++j) { retval = hub_set_address(udev); if (retval >= 0) break; msleep(200); } if (retval < 0) { dev_err(&udev->dev, "device not accepting address %d, error %d\n", udev->devnum, retval); goto fail; } /* cope with hardware quirkiness: * - let SET_ADDRESS settle, some device hardware wants it * - read ep0 maxpacket even for high and low speed, */ msleep(10); if (USE_NEW_SCHEME(retry_counter)) break; retval = usb_get_device_descriptor(udev, 8); if (retval < 8) { dev_err(&udev->dev, "device descriptor " "read/%s, error %d\n", "8", retval); if (retval >= 0) retval = -EMSGSIZE; } else { retval = 0; break; } } if (retval) goto fail; i = udev->descriptor.bMaxPacketSize0; if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) { if (udev->speed != USB_SPEED_FULL || !(i == 8 || i == 16 || i == 32 || i == 64)) { dev_err(&udev->dev, "ep0 maxpacket = %d\n", i); retval = -EMSGSIZE; goto fail; } dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i); udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i); ep0_reinit(udev); } retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE); if (retval < (signed)sizeof(udev->descriptor)) { dev_err(&udev->dev, "device descriptor read/%s, error %d\n", "all", retval); if (retval >= 0) retval = -ENOMSG; goto fail; } retval = 0; fail: if (retval) hub_port_disable(hub, port1, 0); up(&usb_address0_sem); return retval; } static void check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1) { struct usb_qualifier_descriptor *qual; int status; qual = kmalloc (sizeof *qual, SLAB_KERNEL); if (qual == NULL) return; status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0, qual, sizeof *qual); if (status == sizeof *qual) { dev_info(&udev->dev, "not running at top speed; " "connect to a high speed hub\n"); /* hub LEDs are probably harder to miss than syslog */ if (hub->has_indicators) { hub->indicator[port1-1] = INDICATOR_GREEN_BLINK; schedule_work (&hub->leds); } } kfree(qual); } static unsigned hub_power_remaining (struct usb_hub *hub) { struct usb_device *hdev = hub->hdev; int remaining; unsigned i; remaining = hub->power_budget; if (!remaining) /* self-powered */ return 0; for (i = 0; i < hdev->maxchild; i++) { struct usb_device *udev = hdev->children[i]; int delta, ceiling; if (!udev) continue; /* 100mA per-port ceiling, or 8mA for OTG ports */ if (i != (udev->bus->otg_port - 1) || hdev->parent) ceiling = 50; else ceiling = 4; if (udev->actconfig) delta = udev->actconfig->desc.bMaxPower; else delta = ceiling; // dev_dbg(&udev->dev, "budgeted %dmA\n", 2 * delta); if (delta > ceiling) dev_warn(&udev->dev, "%dmA over %dmA budget!\n", 2 * (delta - ceiling), 2 * ceiling); remaining -= delta; } if (remaining < 0) { dev_warn(hub->intfdev, "%dmA over power budget!\n", -2 * remaining); remaining = 0; } return remaining; } /* Handle physical or logical connection change events. * This routine is called when: * a port connection-change occurs; * a port enable-change occurs (often caused by EMI); * usb_reset_device() encounters changed descriptors (as from * a firmware download) * caller already locked the hub */ static void hub_port_connect_change(struct usb_hub *hub, int port1, u16 portstatus, u16 portchange) { struct usb_device *hdev = hub->hdev; struct device *hub_dev = hub->intfdev; int status, i; dev_dbg (hub_dev, "port %d, status %04x, change %04x, %s\n", port1, portstatus, portchange, portspeed (portstatus)); if (hub->has_indicators) { set_port_led(hub, port1, HUB_LED_AUTO); hub->indicator[port1-1] = INDICATOR_AUTO; } /* Disconnect any existing devices under this port */ if (hdev->children[port1-1]) usb_disconnect(&hdev->children[port1-1]); clear_bit(port1, hub->change_bits); #ifdef CONFIG_USB_OTG /* during HNP, don't repeat the debounce */ if (hdev->bus->is_b_host) portchange &= ~USB_PORT_STAT_C_CONNECTION; #endif if (portchange & USB_PORT_STAT_C_CONNECTION) { status = hub_port_debounce(hub, port1); if (status < 0) { dev_err (hub_dev, "connect-debounce failed, port %d disabled\n", port1); goto done; } portstatus = status; } /* Return now if nothing is connected */ if (!(portstatus & USB_PORT_STAT_CONNECTION)) { /* maybe switch power back on (e.g. root hub was reset) */ if ((hub->descriptor->wHubCharacteristics & HUB_CHAR_LPSM) < 2 && !(portstatus & (1 << USB_PORT_FEAT_POWER))) set_port_feature(hdev, port1, USB_PORT_FEAT_POWER); if (portstatus & USB_PORT_STAT_ENABLE) goto done; return; } #ifdef CONFIG_USB_SUSPEND /* If something is connected, but the port is suspended, wake it up. */ if (portstatus & USB_PORT_STAT_SUSPEND) { status = hub_port_resume(hub, port1, NULL); if (status < 0) { dev_dbg(hub_dev, "can't clear suspend on port %d; %d\n", port1, status); goto done; } } #endif for (i = 0; i < SET_CONFIG_TRIES; i++) { struct usb_device *udev; /* reallocate for each attempt, since references * to the previous one can escape in various ways */ udev = usb_alloc_dev(hdev, hdev->bus, port1); if (!udev) { dev_err (hub_dev, "couldn't allocate port %d usb_device\n", port1); goto done; } usb_set_device_state(udev, USB_STATE_POWERED); udev->speed = USB_SPEED_UNKNOWN; /* set the address */ choose_address(udev); if (udev->devnum <= 0) { status = -ENOTCONN; /* Don't retry */ goto loop; } /* reset and get descriptor */ status = hub_port_init(hub, udev, port1, i); if (status < 0) goto loop; /* consecutive bus-powered hubs aren't reliable; they can * violate the voltage drop budget. if the new child has * a "powered" LED, users should notice we didn't enable it * (without reading syslog), even without per-port LEDs * on the parent. */ if (udev->descriptor.bDeviceClass == USB_CLASS_HUB && hub->power_budget) { u16 devstat; status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstat); if (status < 0) { dev_dbg(&udev->dev, "get status %d ?\n", status); goto loop_disable; } cpu_to_le16s(&devstat); if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) { dev_err(&udev->dev, "can't connect bus-powered hub " "to this port\n"); if (hub->has_indicators) { hub->indicator[port1-1] = INDICATOR_AMBER_BLINK; schedule_work (&hub->leds); } status = -ENOTCONN; /* Don't retry */ goto loop_disable; } } /* check for devices running slower than they could */ if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200 && udev->speed == USB_SPEED_FULL && highspeed_hubs != 0) check_highspeed (hub, udev, port1); /* Store the parent's children[] pointer. At this point * udev becomes globally accessible, although presumably * no one will look at it until hdev is unlocked. */ down (&udev->serialize); status = 0; /* We mustn't add new devices if the parent hub has * been disconnected; we would race with the * recursively_mark_NOTATTACHED() routine. */ spin_lock_irq(&device_state_lock); if (hdev->state == USB_STATE_NOTATTACHED) status = -ENOTCONN; else hdev->children[port1-1] = udev; spin_unlock_irq(&device_state_lock); /* Run it through the hoops (find a driver, etc) */ if (!status) { status = usb_new_device(udev); if (status) { spin_lock_irq(&device_state_lock); hdev->children[port1-1] = NULL; spin_unlock_irq(&device_state_lock); } } up (&udev->serialize); if (status) goto loop_disable; status = hub_power_remaining(hub); if (status) dev_dbg(hub_dev, "%dmA power budget left\n", 2 * status); return; loop_disable: hub_port_disable(hub, port1, 1); loop: ep0_reinit(udev); release_address(udev); usb_put_dev(udev); if (status == -ENOTCONN) break; } done: hub_port_disable(hub, port1, 1); } static void hub_events(void) { struct list_head *tmp; struct usb_device *hdev; struct usb_interface *intf; struct usb_hub *hub; struct device *hub_dev; u16 hubstatus; u16 hubchange; u16 portstatus; u16 portchange; int i, ret; int connect_change; /* * We restart the list every time to avoid a deadlock with * deleting hubs downstream from this one. This should be * safe since we delete the hub from the event list. * Not the most efficient, but avoids deadlocks. */ while (1) { /* Grab the first entry at the beginning of the list */ spin_lock_irq(&hub_event_lock); if (list_empty(&hub_event_list)) { spin_unlock_irq(&hub_event_lock); break; } tmp = hub_event_list.next; list_del_init(tmp); hub = list_entry(tmp, struct usb_hub, event_list); hdev = hub->hdev; intf = to_usb_interface(hub->intfdev); hub_dev = &intf->dev; dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n", hdev->state, hub->descriptor ? hub->descriptor->bNbrPorts : 0, /* NOTE: expects max 15 ports... */ (u16) hub->change_bits[0], (u16) hub->event_bits[0]); usb_get_intf(intf); i = hub->resume_root_hub; spin_unlock_irq(&hub_event_lock); /* Is this is a root hub wanting to be resumed? */ if (i) usb_resume_device(hdev); /* Lock the device, then check to see if we were * disconnected while waiting for the lock to succeed. */ if (locktree(hdev) < 0) { usb_put_intf(intf); continue; } if (hub != usb_get_intfdata(intf)) goto loop; /* If the hub has died, clean up after it */ if (hdev->state == USB_STATE_NOTATTACHED) { hub_pre_reset(hub); goto loop; } /* If this is an inactive or suspended hub, do nothing */ if (hub->quiescing) goto loop; if (hub->error) { dev_dbg (hub_dev, "resetting for error %d\n", hub->error); ret = usb_reset_device(hdev); if (ret) { dev_dbg (hub_dev, "error resetting hub: %d\n", ret); goto loop; } hub->nerrors = 0; hub->error = 0; } /* deal with port status changes */ for (i = 1; i <= hub->descriptor->bNbrPorts; i++) { if (test_bit(i, hub->busy_bits)) continue; connect_change = test_bit(i, hub->change_bits); if (!test_and_clear_bit(i, hub->event_bits) && !connect_change && !hub->activating) continue; ret = hub_port_status(hub, i, &portstatus, &portchange); if (ret < 0) continue; if (hub->activating && !hdev->children[i-1] && (portstatus & USB_PORT_STAT_CONNECTION)) connect_change = 1; if (portchange & USB_PORT_STAT_C_CONNECTION) { clear_port_feature(hdev, i, USB_PORT_FEAT_C_CONNECTION); connect_change = 1; } if (portchange & USB_PORT_STAT_C_ENABLE) { if (!connect_change) dev_dbg (hub_dev, "port %d enable change, " "status %08x\n", i, portstatus); clear_port_feature(hdev, i, USB_PORT_FEAT_C_ENABLE); /* * EM interference sometimes causes badly * shielded USB devices to be shutdown by * the hub, this hack enables them again. * Works at least with mouse driver. */ if (!(portstatus & USB_PORT_STAT_ENABLE) && !connect_change && hdev->children[i-1]) { dev_err (hub_dev, "port %i " "disabled by hub (EMI?), " "re-enabling...\n", i); connect_change = 1; } } if (portchange & USB_PORT_STAT_C_SUSPEND) { clear_port_feature(hdev, i, USB_PORT_FEAT_C_SUSPEND); if (hdev->children[i-1]) { ret = remote_wakeup(hdev-> children[i-1]); if (ret < 0) connect_change = 1; } else { ret = -ENODEV; hub_port_disable(hub, i, 1); } dev_dbg (hub_dev, "resume on port %d, status %d\n", i, ret); } if (portchange & USB_PORT_STAT_C_OVERCURRENT) { dev_err (hub_dev, "over-current change on port %d\n", i); clear_port_feature(hdev, i, USB_PORT_FEAT_C_OVER_CURRENT); hub_power_on(hub); } if (portchange & USB_PORT_STAT_C_RESET) { dev_dbg (hub_dev, "reset change on port %d\n", i); clear_port_feature(hdev, i, USB_PORT_FEAT_C_RESET); } if (connect_change) hub_port_connect_change(hub, i, portstatus, portchange); } /* end for i */ /* deal with hub status changes */ if (test_and_clear_bit(0, hub->event_bits) == 0) ; /* do nothing */ else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0) dev_err (hub_dev, "get_hub_status failed\n"); else { if (hubchange & HUB_CHANGE_LOCAL_POWER) { dev_dbg (hub_dev, "power change\n"); clear_hub_feature(hdev, C_HUB_LOCAL_POWER); } if (hubchange & HUB_CHANGE_OVERCURRENT) { dev_dbg (hub_dev, "overcurrent change\n"); msleep(500); /* Cool down */ clear_hub_feature(hdev, C_HUB_OVER_CURRENT); hub_power_on(hub); } } hub->activating = 0; /* If this is a root hub, tell the HCD it's okay to * re-enable port-change interrupts now. */ if (!hdev->parent) usb_enable_root_hub_irq(hdev->bus); loop: usb_unlock_device(hdev); usb_put_intf(intf); } /* end while (1) */ } static int hub_thread(void *__unused) { do { hub_events(); wait_event_interruptible(khubd_wait, !list_empty(&hub_event_list) || kthread_should_stop()); try_to_freeze(); } while (!kthread_should_stop() || !list_empty(&hub_event_list)); pr_debug("%s: khubd exiting\n", usbcore_name); return 0; } static struct usb_device_id hub_id_table [] = { { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS, .bDeviceClass = USB_CLASS_HUB}, { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS, .bInterfaceClass = USB_CLASS_HUB}, { } /* Terminating entry */ }; MODULE_DEVICE_TABLE (usb, hub_id_table); static struct usb_driver hub_driver = { .owner = THIS_MODULE, .name = "hub", .probe = hub_probe, .disconnect = hub_disconnect, .suspend = hub_suspend, .resume = hub_resume, .ioctl = hub_ioctl, .id_table = hub_id_table, }; int usb_hub_init(void) { if (usb_register(&hub_driver) < 0) { printk(KERN_ERR "%s: can't register hub driver\n", usbcore_name); return -1; } khubd_task = kthread_run(hub_thread, NULL, "khubd"); if (!IS_ERR(khubd_task)) return 0; /* Fall through if kernel_thread failed */ usb_deregister(&hub_driver); printk(KERN_ERR "%s: can't start khubd\n", usbcore_name); return -1; } void usb_hub_cleanup(void) { kthread_stop(khubd_task); /* * Hub resources are freed for us by usb_deregister. It calls * usb_driver_purge on every device which in turn calls that * devices disconnect function if it is using this driver. * The hub_disconnect function takes care of releasing the * individual hub resources. -greg */ usb_deregister(&hub_driver); } /* usb_hub_cleanup() */ static int config_descriptors_changed(struct usb_device *udev) { unsigned index; unsigned len = 0; struct usb_config_descriptor *buf; for (index = 0; index < udev->descriptor.bNumConfigurations; index++) { if (len < le16_to_cpu(udev->config[index].desc.wTotalLength)) len = le16_to_cpu(udev->config[index].desc.wTotalLength); } buf = kmalloc (len, SLAB_KERNEL); if (buf == NULL) { dev_err(&udev->dev, "no mem to re-read configs after reset\n"); /* assume the worst */ return 1; } for (index = 0; index < udev->descriptor.bNumConfigurations; index++) { int length; int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength); length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf, old_length); if (length < old_length) { dev_dbg(&udev->dev, "config index %d, error %d\n", index, length); break; } if (memcmp (buf, udev->rawdescriptors[index], old_length) != 0) { dev_dbg(&udev->dev, "config index %d changed (#%d)\n", index, buf->bConfigurationValue); break; } } kfree(buf); return index != udev->descriptor.bNumConfigurations; } /** * usb_reset_device - perform a USB port reset to reinitialize a device * @udev: device to reset (not in SUSPENDED or NOTATTACHED state) * * WARNING - don't reset any device unless drivers for all of its * interfaces are expecting that reset! Maybe some driver->reset() * method should eventually help ensure sufficient cooperation. * * Do a port reset, reassign the device's address, and establish its * former operating configuration. If the reset fails, or the device's * descriptors change from their values before the reset, or the original * configuration and altsettings cannot be restored, a flag will be set * telling khubd to pretend the device has been disconnected and then * re-connected. All drivers will be unbound, and the device will be * re-enumerated and probed all over again. * * Returns 0 if the reset succeeded, -ENODEV if the device has been * flagged for logical disconnection, or some other negative error code * if the reset wasn't even attempted. * * The caller must own the device lock. For example, it's safe to use * this from a driver probe() routine after downloading new firmware. * For calls that might not occur during probe(), drivers should lock * the device using usb_lock_device_for_reset(). */ int usb_reset_device(struct usb_device *udev) { struct usb_device *parent_hdev = udev->parent; struct usb_hub *parent_hub; struct usb_device_descriptor descriptor = udev->descriptor; struct usb_hub *hub = NULL; int i, ret = 0, port1 = -1; if (udev->state == USB_STATE_NOTATTACHED || udev->state == USB_STATE_SUSPENDED) { dev_dbg(&udev->dev, "device reset not allowed in state %d\n", udev->state); return -EINVAL; } if (!parent_hdev) { /* this requires hcd-specific logic; see OHCI hc_restart() */ dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__); return -EISDIR; } for (i = 0; i < parent_hdev->maxchild; i++) if (parent_hdev->children[i] == udev) { port1 = i + 1; break; } if (port1 < 0) { /* If this ever happens, it's very bad */ dev_err(&udev->dev, "Can't locate device's port!\n"); return -ENOENT; } parent_hub = hdev_to_hub(parent_hdev); /* If we're resetting an active hub, take some special actions */ if (udev->actconfig && udev->actconfig->interface[0]->dev.driver == &hub_driver.driver && (hub = hdev_to_hub(udev)) != NULL) { hub_pre_reset(hub); } set_bit(port1, parent_hub->busy_bits); for (i = 0; i < SET_CONFIG_TRIES; ++i) { /* ep0 maxpacket size may change; let the HCD know about it. * Other endpoints will be handled by re-enumeration. */ ep0_reinit(udev); ret = hub_port_init(parent_hub, udev, port1, i); if (ret >= 0) break; } clear_bit(port1, parent_hub->busy_bits); if (ret < 0) goto re_enumerate; /* Device might have changed firmware (DFU or similar) */ if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor) || config_descriptors_changed (udev)) { dev_info(&udev->dev, "device firmware changed\n"); udev->descriptor = descriptor; /* for disconnect() calls */ goto re_enumerate; } if (!udev->actconfig) goto done; ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), USB_REQ_SET_CONFIGURATION, 0, udev->actconfig->desc.bConfigurationValue, 0, NULL, 0, USB_CTRL_SET_TIMEOUT); if (ret < 0) { dev_err(&udev->dev, "can't restore configuration #%d (error=%d)\n", udev->actconfig->desc.bConfigurationValue, ret); goto re_enumerate; } usb_set_device_state(udev, USB_STATE_CONFIGURED); for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { struct usb_interface *intf = udev->actconfig->interface[i]; struct usb_interface_descriptor *desc; /* set_interface resets host side toggle even * for altsetting zero. the interface may have no driver. */ desc = &intf->cur_altsetting->desc; ret = usb_set_interface(udev, desc->bInterfaceNumber, desc->bAlternateSetting); if (ret < 0) { dev_err(&udev->dev, "failed to restore interface %d " "altsetting %d (error=%d)\n", desc->bInterfaceNumber, desc->bAlternateSetting, ret); goto re_enumerate; } } done: if (hub) hub_post_reset(hub); return 0; re_enumerate: hub_port_logical_disconnect(parent_hub, port1); return -ENODEV; }