diff options
Diffstat (limited to 'drivers/usb/core/hub.c')
-rw-r--r-- | drivers/usb/core/hub.c | 3057 |
1 files changed, 3057 insertions, 0 deletions
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c new file mode 100644 index 000000000000..fa0dc4f6de47 --- /dev/null +++ b/drivers/usb/core/hub.c @@ -0,0 +1,3057 @@ +/* + * 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 <linux/config.h> +#ifdef CONFIG_USB_DEBUG + #define DEBUG +#else + #undef DEBUG +#endif +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/completion.h> +#include <linux/sched.h> +#include <linux/list.h> +#include <linux/slab.h> +#include <linux/smp_lock.h> +#include <linux/ioctl.h> +#include <linux/usb.h> +#include <linux/usbdevice_fs.h> + +#include <asm/semaphore.h> +#include <asm/uaccess.h> +#include <asm/byteorder.h> + +#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 pid_t khubd_pid = 0; /* PID of khubd */ +static DECLARE_COMPLETION(khubd_exited); + +/* 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; + + /* 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 for power to be enabled */ + msleep(hub->descriptor->bPwrOn2PwrGood * 2); +} + +static void hub_quiesce(struct usb_hub *hub) +{ + /* stop khubd and related activity */ + hub->quiescing = 1; + 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_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; + } + + switch (hub->descriptor->wHubCharacteristics & HUB_CHAR_TTTT) { + case 0x00: + if (hdev->descriptor.bDeviceProtocol != 0) + dev_dbg(hub_dev, "TT requires at most 8 FS bit times\n"); + break; + case 0x20: + dev_dbg(hub_dev, "TT requires at most 16 FS bit times\n"); + break; + case 0x40: + dev_dbg(hub_dev, "TT requires at most 24 FS bit times\n"); + break; + case 0x60: + dev_dbg(hub_dev, "TT requires at most 32 FS bit times\n"); + 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; + } + cpu_to_le16s(&hubstatus); + 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; + 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; + +static void hub_disconnect(struct usb_interface *intf) +{ + struct usb_hub *hub = usb_get_intfdata (intf); + struct usb_device *hdev; + + if (!hub) + return; + hdev = hub->hdev; + + if (hdev->speed == USB_SPEED_HIGH) + highspeed_hubs--; + + usb_set_intfdata (intf, NULL); + + 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); + + if (hub->descriptor) { + kfree(hub->descriptor); + hub->descriptor = NULL; + } + + if (hub->status) { + kfree(hub->status); + hub->status = NULL; + } + + if (hub->buffer) { + usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer, + hub->buffer_dma); + hub->buffer = NULL; + } + + /* Free the memory */ + kfree(hub); +} + +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; + 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); + 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, pm_message_t state); + err = __usb_suspend_device(udev, + udev->bus->otg_port, + PMSG_SUSPEND); + 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 */ + 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) + dev_dbg(hub->intfdev, + "port_wait_reset: err = %d\n", + status); + } + + /* return on disconnect or reset */ + switch (status) { + case 0: + /* TRSTRCY = 10 ms */ + msleep(10); + /* 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; +} + +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; +} + +/* + * 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 + * - usb_suspend_device(dev,PM_SUSPEND_DISK) + * 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 (udev->actconfig + // && FIXME (remote wakeup enabled on this bus) + // ... currently assuming it's always appropriate + && (udev->actconfig->desc.bmAttributes + & USB_CONFIG_ATT_WAKEUP) != 0) { + 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 (PM_SUSPEND_MEM), "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. + */ +static int __usb_suspend_device (struct usb_device *udev, int port1, + pm_message_t state) +{ + 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; + } + + /* suspend interface drivers; if this is a hub, it + * suspends the child devices + */ + if (udev->actconfig) { + int i; + + for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { + struct usb_interface *intf; + struct usb_driver *driver; + + intf = udev->actconfig->interface[i]; + if (state <= intf->dev.power.power_state) + continue; + if (!intf->dev.driver) + continue; + driver = to_usb_driver(intf->dev.driver); + + if (driver->suspend) { + status = driver->suspend(intf, state); + if (intf->dev.power.power_state != state + || status) + dev_err(&intf->dev, + "suspend %d fail, code %d\n", + state, status); + } + + /* only drivers with suspend() can ever resume(); + * and after power loss, even they won't. + * bus_rescan_devices() can rebind drivers later. + * + * FIXME the PM core self-deadlocks when unbinding + * drivers during suspend/resume ... everything grabs + * dpm_sem (not a spinlock, ugh). we want to unbind, + * since we know every driver's probe/disconnect works + * even for drivers that can't suspend. + */ + if (!driver->suspend || state > PM_SUSPEND_MEM) { +#if 1 + dev_warn(&intf->dev, "resume is unsafe!\n"); +#else + down_write(&usb_bus_type.rwsem); + device_release_driver(&intf->dev); + up_write(&usb_bus_type.rwsem); +#endif + } + } + } + + /* + * FIXME this needs port power off call paths too, to help force + * USB into the "generic" PM model. At least for devices on + * ports that aren't using ganged switching (usually root hubs). + * + * NOTE: SRP-capable links should adopt more aggressive poweroff + * policies (when HNP doesn't apply) once we have mechanisms to + * turn power back on! (Likely not before 2.7...) + */ + if (state > PM_SUSPEND_MEM) { + dev_warn(&udev->dev, "no poweroff yet, suspending instead\n"); + } + + /* "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 = state; + return status; +} + +/** + * usb_suspend_device - suspend a usb device + * @udev: device that's no longer in active use + * @state: PMSG_SUSPEND to suspend + * 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. + * + * 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, pm_message_t state) +{ + int port1, status; + + port1 = locktree(udev); + if (port1 < 0) + return port1; + + status = __usb_suspend_device(udev, port1, state); + usb_unlock_device(udev); + return status; +} + +/* + * 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; + + 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 + * resumes the child devices + */ + for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { + struct usb_interface *intf; + struct usb_driver *driver; + + intf = udev->actconfig->interface[i]; + if (intf->dev.power.power_state == PM_SUSPEND_ON) + continue; + if (!intf->dev.driver) { + /* FIXME maybe force to alt 0 */ + continue; + } + driver = to_usb_driver(intf->dev.driver); + + /* bus_rescan_devices() may rebind drivers */ + if (!driver->resume) + continue; + + /* can we do better than just logging errors? */ + status = driver->resume(intf); + if (intf->dev.power.power_state != PM_SUSPEND_ON + || status) + dev_dbg(&intf->dev, + "resume fail, state %d code %d\n", + intf->dev.power.power_state, status); + } + 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 state) +{ + struct usb_hub *hub = usb_get_intfdata (intf); + struct usb_device *hdev = hub->hdev; + unsigned port1; + int status; + + /* stop khubd and related activity */ + hub_quiesce(hub); + + /* then suspend every port */ + for (port1 = 1; port1 <= hdev->maxchild; port1++) { + struct usb_device *udev; + + udev = hdev->children [port1-1]; + if (!udev) + continue; + down(&udev->serialize); + status = __usb_suspend_device(udev, port1, state); + up(&udev->serialize); + if (status < 0) + dev_dbg(&intf->dev, "suspend port %d --> %d\n", + port1, status); + } + + intf->dev.power.power_state = state; + 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; + + if (intf->dev.power.power_state == PM_SUSPEND_ON) + return 0; + + 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); + } + intf->dev.power.power_state = PMSG_ON; + + 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, pm_message_t state) +{ + return 0; +} + +int usb_resume_device(struct usb_device *udev) +{ + 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; + +loop: + usb_unlock_device(hdev); + usb_put_intf(intf); + + } /* end while (1) */ +} + +static int hub_thread(void *__unused) +{ + /* + * This thread doesn't need any user-level access, + * so get rid of all our resources + */ + + daemonize("khubd"); + allow_signal(SIGKILL); + + /* Send me a signal to get me die (for debugging) */ + do { + hub_events(); + wait_event_interruptible(khubd_wait, !list_empty(&hub_event_list)); + try_to_freeze(PF_FREEZE); + } while (!signal_pending(current)); + + pr_debug ("%s: khubd exiting\n", usbcore_name); + complete_and_exit(&khubd_exited, 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) +{ + pid_t pid; + + if (usb_register(&hub_driver) < 0) { + printk(KERN_ERR "%s: can't register hub driver\n", + usbcore_name); + return -1; + } + + pid = kernel_thread(hub_thread, NULL, CLONE_KERNEL); + if (pid >= 0) { + khubd_pid = pid; + + 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) +{ + int ret; + + /* Kill the thread */ + ret = kill_proc(khubd_pid, SIGKILL, 1); + + wait_for_completion(&khubd_exited); + + /* + * 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; +} |