unsigned limited_power:1;
unsigned quiescing:1;
- unsigned activating:1;
unsigned disconnected:1;
unsigned has_indicators:1;
u8 indicator[USB_MAXCHILDREN];
struct delayed_work leds;
+ struct delayed_work init_work;
};
MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
/*
+ * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
+ * 10 seconds to send reply for the initial 64-byte descriptor request.
+ */
+/* define initial 64-byte descriptor request timeout in milliseconds */
+static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
+module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(initial_descriptor_timeout,
+ "initial 64-byte descriptor request timeout in milliseconds "
+ "(default 5000 - 5.0 seconds)");
+
+/*
* 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
DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
+#define HUB_DEBOUNCE_TIMEOUT 1500
+#define HUB_DEBOUNCE_STEP 25
+#define HUB_DEBOUNCE_STABLE 100
+
+
+static int usb_reset_and_verify_device(struct usb_device *udev);
static inline char *portspeed(int portstatus)
{
}
EXPORT_SYMBOL_GPL(usb_hub_tt_clear_buffer);
-static void hub_power_on(struct usb_hub *hub)
+/* If do_delay is false, return the number of milliseconds the caller
+ * needs to delay.
+ */
+static unsigned hub_power_on(struct usb_hub *hub, bool do_delay)
{
int port1;
unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
+ unsigned delay;
u16 wHubCharacteristics =
le16_to_cpu(hub->descriptor->wHubCharacteristics);
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)
-{
- /* (nonblocking) khubd and related activity won't re-trigger */
- hub->quiescing = 1;
- hub->activating = 0;
-
- /* (blocking) stop khubd and related activity */
- usb_kill_urb(hub->urb);
- if (hub->has_indicators)
- cancel_delayed_work_sync(&hub->leds);
- if (hub->tt.hub)
- cancel_work_sync(&hub->tt.kevent);
-}
-
-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);
+ delay = max(pgood_delay, (unsigned) 100);
+ if (do_delay)
+ msleep(delay);
+ return delay;
}
static int hub_hub_status(struct usb_hub *hub,
ret = get_hub_status(hub->hdev, &hub->status->hub);
if (ret < 0)
dev_err (hub->intfdev,
- "%s failed (err = %d)\n", __FUNCTION__, ret);
+ "%s failed (err = %d)\n", __func__, ret);
else {
*status = le16_to_cpu(hub->status->hub.wHubStatus);
*change = le16_to_cpu(hub->status->hub.wHubChange);
kick_khubd(hub);
}
-/* caller has locked the hub device */
-static void hub_stop(struct usb_hub *hub)
-{
- struct usb_device *hdev = hub->hdev;
- int i;
-
- /* Disconnect all the children */
- for (i = 0; i < hdev->maxchild; ++i) {
- if (hdev->children[i])
- usb_disconnect(&hdev->children[i]);
- }
- hub_quiesce(hub);
-}
-
-#define HUB_RESET 1
-#define HUB_RESUME 2
-#define HUB_RESET_RESUME 3
+enum hub_activation_type {
+ HUB_INIT, HUB_INIT2, HUB_INIT3,
+ HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
+};
-#ifdef CONFIG_PM
+static void hub_init_func2(struct work_struct *ws);
+static void hub_init_func3(struct work_struct *ws);
-static void hub_restart(struct usb_hub *hub, int type)
+static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
{
struct usb_device *hdev = hub->hdev;
int port1;
+ int status;
+ bool need_debounce_delay = false;
+ unsigned delay;
+
+ /* Continue a partial initialization */
+ if (type == HUB_INIT2)
+ goto init2;
+ if (type == HUB_INIT3)
+ goto init3;
+
+ /* After a resume, port power should still be on.
+ * For any other type of activation, turn it on.
+ */
+ if (type != HUB_RESUME) {
+
+ /* Speed up system boot by using a delayed_work for the
+ * hub's initial power-up delays. This is pretty awkward
+ * and the implementation looks like a home-brewed sort of
+ * setjmp/longjmp, but it saves at least 100 ms for each
+ * root hub (assuming usbcore is compiled into the kernel
+ * rather than as a module). It adds up.
+ *
+ * This can't be done for HUB_RESUME or HUB_RESET_RESUME
+ * because for those activation types the ports have to be
+ * operational when we return. In theory this could be done
+ * for HUB_POST_RESET, but it's easier not to.
+ */
+ if (type == HUB_INIT) {
+ delay = hub_power_on(hub, false);
+ PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2);
+ schedule_delayed_work(&hub->init_work,
+ msecs_to_jiffies(delay));
+
+ /* Suppress autosuspend until init is done */
+ to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
+ return; /* Continues at init2: below */
+ } else {
+ hub_power_on(hub, true);
+ }
+ }
+ init2:
- /* Check each of the children to see if they require
- * USB-PERSIST handling or disconnection. Also check
- * each unoccupied port to make sure it is still disabled.
+ /* Check each port and set hub->change_bits to let khubd know
+ * which ports need attention.
*/
for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
struct usb_device *udev = hdev->children[port1-1];
- int status = 0;
u16 portstatus, portchange;
- if (!udev || udev->state == USB_STATE_NOTATTACHED) {
- if (type != HUB_RESET) {
- status = hub_port_status(hub, port1,
- &portstatus, &portchange);
- if (status == 0 && (portstatus &
- USB_PORT_STAT_ENABLE))
- clear_port_feature(hdev, port1,
- USB_PORT_FEAT_ENABLE);
- }
- continue;
- }
+ portstatus = portchange = 0;
+ status = hub_port_status(hub, port1, &portstatus, &portchange);
+ if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
+ dev_dbg(hub->intfdev,
+ "port %d: status %04x change %04x\n",
+ port1, portstatus, portchange);
- /* Was the power session lost while we were suspended? */
- switch (type) {
- case HUB_RESET_RESUME:
- portstatus = 0;
- portchange = USB_PORT_STAT_C_CONNECTION;
- break;
+ /* After anything other than HUB_RESUME (i.e., initialization
+ * or any sort of reset), every port should be disabled.
+ * Unconnected ports should likewise be disabled (paranoia),
+ * and so should ports for which we have no usb_device.
+ */
+ if ((portstatus & USB_PORT_STAT_ENABLE) && (
+ type != HUB_RESUME ||
+ !(portstatus & USB_PORT_STAT_CONNECTION) ||
+ !udev ||
+ udev->state == USB_STATE_NOTATTACHED)) {
+ clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
+ portstatus &= ~USB_PORT_STAT_ENABLE;
+ }
- case HUB_RESET:
- case HUB_RESUME:
- status = hub_port_status(hub, port1,
- &portstatus, &portchange);
- break;
+ /* Clear status-change flags; we'll debounce later */
+ if (portchange & USB_PORT_STAT_C_CONNECTION) {
+ need_debounce_delay = true;
+ clear_port_feature(hub->hdev, port1,
+ USB_PORT_FEAT_C_CONNECTION);
+ }
+ if (portchange & USB_PORT_STAT_C_ENABLE) {
+ need_debounce_delay = true;
+ clear_port_feature(hub->hdev, port1,
+ USB_PORT_FEAT_C_ENABLE);
}
- /* For "USB_PERSIST"-enabled children we must
- * mark the child device for reset-resume and
- * turn off the various status changes to prevent
- * khubd from disconnecting it later.
- */
- if (udev->persist_enabled && status == 0 &&
- !(portstatus & USB_PORT_STAT_ENABLE)) {
- if (portchange & USB_PORT_STAT_C_ENABLE)
- clear_port_feature(hub->hdev, port1,
- USB_PORT_FEAT_C_ENABLE);
- if (portchange & USB_PORT_STAT_C_CONNECTION)
- clear_port_feature(hub->hdev, port1,
- USB_PORT_FEAT_C_CONNECTION);
+ if (!udev || udev->state == USB_STATE_NOTATTACHED) {
+ /* Tell khubd to disconnect the device or
+ * check for a new connection
+ */
+ if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
+ set_bit(port1, hub->change_bits);
+
+ } else if (portstatus & USB_PORT_STAT_ENABLE) {
+ /* The power session apparently survived the resume.
+ * If there was an overcurrent or suspend change
+ * (i.e., remote wakeup request), have khubd
+ * take care of it.
+ */
+ if (portchange)
+ set_bit(port1, hub->change_bits);
+
+ } else if (udev->persist_enabled) {
+#ifdef CONFIG_PM
udev->reset_resume = 1;
+#endif
+ set_bit(port1, hub->change_bits);
+
+ } else {
+ /* The power session is gone; tell khubd */
+ usb_set_device_state(udev, USB_STATE_NOTATTACHED);
+ set_bit(port1, hub->change_bits);
}
+ }
- /* Otherwise for a reset_resume we must disconnect the child,
- * but as we may not lock the child device here
- * we have to do a "logical" disconnect.
- */
- else if (type == HUB_RESET_RESUME)
- hub_port_logical_disconnect(hub, port1);
+ /* If no port-status-change flags were set, we don't need any
+ * debouncing. If flags were set we can try to debounce the
+ * ports all at once right now, instead of letting khubd do them
+ * one at a time later on.
+ *
+ * If any port-status changes do occur during this delay, khubd
+ * will see them later and handle them normally.
+ */
+ if (need_debounce_delay) {
+ delay = HUB_DEBOUNCE_STABLE;
+
+ /* Don't do a long sleep inside a workqueue routine */
+ if (type == HUB_INIT2) {
+ PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func3);
+ schedule_delayed_work(&hub->init_work,
+ msecs_to_jiffies(delay));
+ return; /* Continues at init3: below */
+ } else {
+ msleep(delay);
+ }
}
+ init3:
+ hub->quiescing = 0;
+
+ 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);
- hub_activate(hub);
+ /* Scan all ports that need attention */
+ kick_khubd(hub);
}
-#endif /* CONFIG_PM */
+/* Implement the continuations for the delays above */
+static void hub_init_func2(struct work_struct *ws)
+{
+ struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
+
+ hub_activate(hub, HUB_INIT2);
+}
+
+static void hub_init_func3(struct work_struct *ws)
+{
+ struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
+
+ hub_activate(hub, HUB_INIT3);
+}
+
+enum hub_quiescing_type {
+ HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
+};
+
+static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
+{
+ struct usb_device *hdev = hub->hdev;
+ int i;
+
+ cancel_delayed_work_sync(&hub->init_work);
+
+ /* khubd and related activity won't re-trigger */
+ hub->quiescing = 1;
+
+ if (type != HUB_SUSPEND) {
+ /* Disconnect all the children */
+ for (i = 0; i < hdev->maxchild; ++i) {
+ if (hdev->children[i])
+ usb_disconnect(&hdev->children[i]);
+ }
+ }
+
+ /* Stop khubd and related activity */
+ usb_kill_urb(hub->urb);
+ if (hub->has_indicators)
+ cancel_delayed_work_sync(&hub->leds);
+ if (hub->tt.hub)
+ cancel_work_sync(&hub->tt.kevent);
+}
/* caller has locked the hub device */
static int hub_pre_reset(struct usb_interface *intf)
{
struct usb_hub *hub = usb_get_intfdata(intf);
- hub_stop(hub);
+ hub_quiesce(hub, HUB_PRE_RESET);
return 0;
}
{
struct usb_hub *hub = usb_get_intfdata(intf);
- hub_power_on(hub);
- hub_activate(hub);
+ hub_activate(hub, HUB_POST_RESET);
return 0;
}
if (hub->has_indicators && blinkenlights)
hub->indicator [0] = INDICATOR_CYCLE;
- hub_power_on(hub);
- hub_activate(hub);
+ hub_activate(hub, HUB_INIT);
return 0;
fail:
/* Disconnect all children and quiesce the hub */
hub->error = 0;
- hub_stop(hub);
+ hub_quiesce(hub, HUB_DISCONNECT);
usb_set_intfdata (intf, NULL);
desc = intf->cur_altsetting;
hdev = interface_to_usbdev(intf);
+ if (hdev->level == MAX_TOPO_LEVEL) {
+ dev_err(&intf->dev,
+ "Unsupported bus topology: hub nested too deep\n");
+ return -E2BIG;
+ }
+
#ifdef CONFIG_USB_OTG_BLACKLIST_HUB
if (hdev->parent) {
dev_warn(&intf->dev, "ignoring external hub\n");
hub->intfdev = &intf->dev;
hub->hdev = hdev;
INIT_DELAYED_WORK(&hub->leds, led_work);
+ INIT_DELAYED_WORK(&hub->init_work, NULL);
usb_get_intf(intf);
usb_set_intfdata (intf, hub);
recursively_mark_NOTATTACHED(udev);
spin_unlock_irqrestore(&device_state_lock, flags);
}
+EXPORT_SYMBOL_GPL(usb_set_device_state);
+/*
+ * WUSB devices are simple: they have no hubs behind, so the mapping
+ * device <-> virtual port number becomes 1:1. Why? to simplify the
+ * life of the device connection logic in
+ * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
+ * handshake we need to assign a temporary address in the unauthorized
+ * space. For simplicity we use the first virtual port number found to
+ * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
+ * and that becomes it's address [X < 128] or its unauthorized address
+ * [X | 0x80].
+ *
+ * We add 1 as an offset to the one-based USB-stack port number
+ * (zero-based wusb virtual port index) for two reasons: (a) dev addr
+ * 0 is reserved by USB for default address; (b) Linux's USB stack
+ * uses always #1 for the root hub of the controller. So USB stack's
+ * port #1, which is wusb virtual-port #0 has address #2.
+ */
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 (udev->wusb) {
+ devnum = udev->portnum + 1;
+ BUG_ON(test_bit(devnum, bus->devmap.devicemap));
+ } else {
+ /* 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 update_address(struct usb_device *udev, int devnum)
+{
+ /* The address for a WUSB device is managed by wusbcore. */
+ if (!udev->wusb)
+ udev->devnum = devnum;
+}
+
#ifdef CONFIG_USB_SUSPEND
static void usb_stop_pm(struct usb_device *udev)
usb_autosuspend_device(udev->parent);
usb_pm_unlock(udev);
- /* Stop any autosuspend requests already submitted */
- cancel_rearming_delayed_work(&udev->autosuspend);
+ /* Stop any autosuspend or autoresume requests already submitted */
+ cancel_delayed_work_sync(&udev->autosuspend);
+ cancel_work_sync(&udev->autoresume);
}
#else
int i;
if (!udev) {
- pr_debug ("%s nodev\n", __FUNCTION__);
+ pr_debug ("%s nodev\n", __func__);
return;
}
*/
dev_dbg (&udev->dev, "unregistering device\n");
usb_disable_device(udev, 0);
+ usb_hcd_synchronize_unlinks(udev);
+ usb_remove_ep_devs(&udev->ep0);
usb_unlock_device(udev);
/* Unregister the device. The device driver is responsible
- * for removing the device files from usbfs and sysfs and for
- * de-configuring the device.
+ * for de-configuring the device and invoking the remove-device
+ * notifier chain (used by usbfs and possibly others).
*/
device_del(&udev->dev);
dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
le16_to_cpu(udev->descriptor.idVendor),
le16_to_cpu(udev->descriptor.idProduct));
- dev_info(&udev->dev, "New USB device strings: Mfr=%d, Product=%d, "
- "SerialNumber=%d\n",
+ dev_info(&udev->dev,
+ "New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
udev->descriptor.iManufacturer,
udev->descriptor.iProduct,
udev->descriptor.iSerialNumber);
* customize to match your product.
*/
dev_info(&udev->dev,
- "can't set HNP mode; %d\n",
+ "can't set HNP mode: %d\n",
err);
bus->b_hnp_enable = 0;
}
* (Includes HNP test device.)
*/
if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
- err = usb_port_suspend(udev);
+ err = usb_port_suspend(udev, PMSG_SUSPEND);
if (err < 0)
dev_dbg(&udev->dev, "HNP fail, %d\n", err);
}
{
int err;
+ /* Increment the parent's count of unsuspended children */
+ if (udev->parent)
+ usb_autoresume_device(udev->parent);
+
usb_detect_quirks(udev); /* Determine quirks */
err = usb_configure_device(udev); /* detect & probe dev/intfs */
if (err < 0)
udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
- /* Increment the parent's count of unsuspended children */
- if (udev->parent)
- usb_autoresume_device(udev->parent);
+ /* Tell the world! */
+ announce_device(udev);
/* Register the device. The device driver is responsible
- * for adding the device files to sysfs and for configuring
- * the device.
+ * for configuring the device and invoking the add-device
+ * notifier chain (used by usbfs and possibly others).
*/
err = device_add(&udev->dev);
if (err) {
goto fail;
}
- /* Tell the world! */
- announce_device(udev);
+ (void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
return err;
fail:
usb_set_device_state(udev, USB_STATE_NOTATTACHED);
+ usb_stop_pm(udev);
return err;
}
case 0:
/* TRSTRCY = 10 ms; plus some extra */
msleep(10 + 40);
- udev->devnum = 0; /* Device now at address 0 */
+ update_address(udev, 0);
/* FALL THROUGH */
case -ENOTCONN:
case -ENODEV:
#ifdef CONFIG_PM
+#define MASK_BITS (USB_PORT_STAT_POWER | USB_PORT_STAT_CONNECTION | \
+ USB_PORT_STAT_SUSPEND)
+#define WANT_BITS (USB_PORT_STAT_POWER | USB_PORT_STAT_CONNECTION)
+
+/* Determine whether the device on a port is ready for a normal resume,
+ * is ready for a reset-resume, or should be disconnected.
+ */
+static int check_port_resume_type(struct usb_device *udev,
+ struct usb_hub *hub, int port1,
+ int status, unsigned portchange, unsigned portstatus)
+{
+ /* Is the device still present? */
+ if (status || (portstatus & MASK_BITS) != WANT_BITS) {
+ if (status >= 0)
+ status = -ENODEV;
+ }
+
+ /* Can't do a normal resume if the port isn't enabled,
+ * so try a reset-resume instead.
+ */
+ else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
+ if (udev->persist_enabled)
+ udev->reset_resume = 1;
+ else
+ status = -ENODEV;
+ }
+
+ if (status) {
+ dev_dbg(hub->intfdev,
+ "port %d status %04x.%04x after resume, %d\n",
+ port1, portchange, portstatus, status);
+ } else if (udev->reset_resume) {
+
+ /* Late port handoff can set status-change bits */
+ if (portchange & USB_PORT_STAT_C_CONNECTION)
+ clear_port_feature(hub->hdev, port1,
+ USB_PORT_FEAT_C_CONNECTION);
+ if (portchange & USB_PORT_STAT_C_ENABLE)
+ clear_port_feature(hub->hdev, port1,
+ USB_PORT_FEAT_C_ENABLE);
+ }
+
+ return status;
+}
+
#ifdef CONFIG_USB_SUSPEND
/*
*
* Returns 0 on success, else negative errno.
*/
-int usb_port_suspend(struct usb_device *udev)
+int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
{
struct usb_hub *hub = hdev_to_hub(udev->parent);
int port1 = udev->portnum;
} else {
/* device has up to 10 msec to fully suspend */
dev_dbg(&udev->dev, "usb %ssuspend\n",
- udev->auto_pm ? "auto-" : "");
+ (msg.event & PM_EVENT_AUTO ? "auto-" : ""));
usb_set_device_state(udev, USB_STATE_SUSPENDED);
msleep(10);
}
u16 devstatus;
/* caller owns the udev device lock */
- dev_dbg(&udev->dev, "finish %sresume\n",
- udev->reset_resume ? "reset-" : "");
+ dev_dbg(&udev->dev, "%s\n",
+ udev->reset_resume ? "finish reset-resume" : "finish resume");
/* usb ch9 identifies four variants of SUSPENDED, based on what
* state the device resumes to. Linux currently won't see the
* resumed.
*/
if (udev->reset_resume)
- status = usb_reset_device(udev);
+ retry_reset_resume:
+ status = usb_reset_and_verify_device(udev);
/* 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,
status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
if (status >= 0)
status = (status > 0 ? 0 : -ENODEV);
+
+ /* If a normal resume failed, try doing a reset-resume */
+ if (status && !udev->reset_resume && udev->persist_enabled) {
+ dev_dbg(&udev->dev, "retry with reset-resume\n");
+ udev->reset_resume = 1;
+ goto retry_reset_resume;
+ }
}
if (status) {
NULL, 0,
USB_CTRL_SET_TIMEOUT);
if (status)
- dev_dbg(&udev->dev, "disable remote "
- "wakeup, status %d\n", status);
+ dev_dbg(&udev->dev,
+ "disable remote wakeup, status %d\n",
+ status);
}
status = 0;
}
* to it will be lost. Using the USB_PERSIST facility, the device can be
* made to appear as if it had not disconnected.
*
- * This facility can be dangerous. Although usb_reset_device() makes
+ * This facility can be dangerous. Although usb_reset_and_verify_device() makes
* every effort to insure that the same device is present after the
* reset as before, it cannot provide a 100% guarantee. Furthermore it's
* quite possible for a device to remain unaltered but its media to be
*
* Returns 0 on success, else negative errno.
*/
-int usb_port_resume(struct usb_device *udev)
+int usb_port_resume(struct usb_device *udev, pm_message_t msg)
{
struct usb_hub *hub = hdev_to_hub(udev->parent);
int port1 = udev->portnum;
int status;
u16 portchange, portstatus;
- unsigned mask_flags, want_flags;
/* Skip the initial Clear-Suspend step for a remote wakeup */
status = hub_port_status(hub, port1, &portstatus, &portchange);
} else {
/* drive resume for at least 20 msec */
dev_dbg(&udev->dev, "usb %sresume\n",
- udev->auto_pm ? "auto-" : "");
+ (msg.event & PM_EVENT_AUTO ? "auto-" : ""));
msleep(25);
/* Virtual root hubs can trigger on GET_PORT_STATUS to
*/
status = hub_port_status(hub, port1, &portstatus, &portchange);
- SuspendCleared:
- if (udev->reset_resume)
- want_flags = USB_PORT_STAT_POWER
- | USB_PORT_STAT_CONNECTION;
- else
- want_flags = USB_PORT_STAT_POWER
- | USB_PORT_STAT_CONNECTION
- | USB_PORT_STAT_ENABLE;
- mask_flags = want_flags | USB_PORT_STAT_SUSPEND;
+ /* TRSMRCY = 10 msec */
+ msleep(10);
+ }
- if (status < 0 || (portstatus & mask_flags) != want_flags) {
- dev_dbg(hub->intfdev,
- "port %d status %04x.%04x after resume, %d\n",
- port1, portchange, portstatus, status);
- if (status >= 0)
- status = -ENODEV;
- } else {
- if (portchange & USB_PORT_STAT_C_SUSPEND)
- clear_port_feature(hub->hdev, port1,
- USB_PORT_FEAT_C_SUSPEND);
- /* TRSMRCY = 10 msec */
- msleep(10);
- }
+ SuspendCleared:
+ if (status == 0) {
+ if (portchange & USB_PORT_STAT_C_SUSPEND)
+ clear_port_feature(hub->hdev, port1,
+ USB_PORT_FEAT_C_SUSPEND);
}
clear_bit(port1, hub->busy_bits);
+ status = check_port_resume_type(udev,
+ hub, port1, status, portchange, portstatus);
if (status == 0)
status = finish_port_resume(udev);
if (status < 0) {
return status;
}
+/* caller has locked udev */
static int remote_wakeup(struct usb_device *udev)
{
int status = 0;
- usb_lock_device(udev);
if (udev->state == USB_STATE_SUSPENDED) {
dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
usb_mark_last_busy(udev);
- status = usb_external_resume_device(udev);
+ status = usb_external_resume_device(udev, PMSG_REMOTE_RESUME);
}
- usb_unlock_device(udev);
return status;
}
/* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
-int usb_port_suspend(struct usb_device *udev)
+int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
{
return 0;
}
-int usb_port_resume(struct usb_device *udev)
+/* However we may need to do a reset-resume */
+
+int usb_port_resume(struct usb_device *udev, pm_message_t msg)
{
- int status = 0;
+ struct usb_hub *hub = hdev_to_hub(udev->parent);
+ int port1 = udev->portnum;
+ int status;
+ u16 portchange, portstatus;
+
+ status = hub_port_status(hub, port1, &portstatus, &portchange);
+ status = check_port_resume_type(udev,
+ hub, port1, status, portchange, portstatus);
- /* However we may need to do a reset-resume */
- if (udev->reset_resume) {
+ if (status) {
+ dev_dbg(&udev->dev, "can't resume, status %d\n", status);
+ hub_port_logical_disconnect(hub, port1);
+ } else if (udev->reset_resume) {
dev_dbg(&udev->dev, "reset-resume\n");
- status = usb_reset_device(udev);
+ status = usb_reset_and_verify_device(udev);
}
return status;
}
udev = hdev->children [port1-1];
if (udev && udev->can_submit) {
- if (!hdev->auto_pm)
+ if (!(msg.event & PM_EVENT_AUTO))
dev_dbg(&intf->dev, "port %d nyet suspended\n",
port1);
return -EBUSY;
}
}
- dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
+ dev_dbg(&intf->dev, "%s\n", __func__);
/* stop khubd and related activity */
- hub_quiesce(hub);
+ hub_quiesce(hub, HUB_SUSPEND);
return 0;
}
struct usb_hub *hub = usb_get_intfdata(intf);
dev_dbg(&intf->dev, "%s\n", __func__);
- hub_restart(hub, HUB_RESUME);
+ hub_activate(hub, HUB_RESUME);
return 0;
}
struct usb_hub *hub = usb_get_intfdata(intf);
dev_dbg(&intf->dev, "%s\n", __func__);
- hub_power_on(hub);
- hub_restart(hub, HUB_RESET_RESUME);
+ hub_activate(hub, HUB_RESET_RESUME);
return 0;
}
* 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;
return portstatus;
}
-static void ep0_reinit(struct usb_device *udev)
+void usb_ep0_reinit(struct usb_device *udev)
{
- usb_disable_endpoint(udev, 0 + USB_DIR_IN);
- usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
- usb_enable_endpoint(udev, &udev->ep0);
+ usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
+ usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
+ usb_enable_endpoint(udev, &udev->ep0, true);
}
+EXPORT_SYMBOL_GPL(usb_ep0_reinit);
#define usb_sndaddr0pipe() (PIPE_CONTROL << 30)
#define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
USB_REQ_SET_ADDRESS, 0, devnum, 0,
NULL, 0, USB_CTRL_SET_TIMEOUT);
if (retval == 0) {
- udev->devnum = devnum; /* Device now using proper address */
+ /* Device now using proper address. */
+ update_address(udev, devnum);
usb_set_device_state(udev, USB_STATE_ADDRESS);
- ep0_reinit(udev);
+ usb_ep0_reinit(udev);
}
return retval;
}
* 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
+ * usb_reset_and_verify_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.
*/
*/
switch (udev->speed) {
case USB_SPEED_VARIABLE: /* fixed at 512 */
- udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(512);
+ udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
break;
case USB_SPEED_HIGH: /* fixed at 64 */
- udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
+ udev->ep0.desc.wMaxPacketSize = 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);
+ udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
break;
case USB_SPEED_LOW: /* fixed at 8 */
- udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
+ udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
break;
default:
goto fail;
USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
USB_DT_DEVICE << 8, 0,
buf, GET_DESCRIPTOR_BUFSIZE,
- USB_CTRL_GET_TIMEOUT);
+ initial_descriptor_timeout);
switch (buf->bMaxPacketSize0) {
case 8: case 16: case 32: case 64: case 255:
if (buf->bDescriptorType ==
goto fail;
}
if (r) {
- dev_err(&udev->dev, "device descriptor "
- "read/%s, error %d\n",
- "64", r);
+ dev_err(&udev->dev,
+ "device descriptor read/64, error %d\n",
+ r);
retval = -EMSGSIZE;
continue;
}
#undef GET_DESCRIPTOR_BUFSIZE
}
- for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
- retval = hub_set_address(udev, devnum);
- if (retval >= 0)
+ /*
+ * If device is WUSB, we already assigned an
+ * unauthorized address in the Connect Ack sequence;
+ * authorization will assign the final address.
+ */
+ if (udev->wusb == 0) {
+ for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
+ retval = hub_set_address(udev, devnum);
+ if (retval >= 0)
+ break;
+ msleep(200);
+ }
+ if (retval < 0) {
+ dev_err(&udev->dev,
+ "device not accepting address %d, error %d\n",
+ 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;
- msleep(200);
- }
- if (retval < 0) {
- dev_err(&udev->dev,
- "device not accepting address %d, error %d\n",
- 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);
+ dev_err(&udev->dev,
+ "device descriptor read/8, error %d\n",
+ retval);
if (retval >= 0)
retval = -EMSGSIZE;
} else {
if (retval)
goto fail;
- i = udev->descriptor.bMaxPacketSize0 == 0xff?
+ i = udev->descriptor.bMaxPacketSize0 == 0xff? /* wusb device? */
512 : udev->descriptor.bMaxPacketSize0;
if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
if (udev->speed != USB_SPEED_FULL ||
}
dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
- ep0_reinit(udev);
+ usb_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);
+ dev_err(&udev->dev, "device descriptor read/all, error %d\n",
+ retval);
if (retval >= 0)
retval = -ENOMSG;
goto fail;
fail:
if (retval) {
hub_port_disable(hub, port1, 0);
- udev->devnum = devnum; /* for disconnect processing */
+ update_address(udev, devnum); /* for disconnect processing */
}
mutex_unlock(&usb_address0_mutex);
return retval;
else
delta = 8;
if (delta > hub->mA_per_port)
- dev_warn(&udev->dev, "%dmA is over %umA budget "
- "for port %d!\n",
- delta, hub->mA_per_port, port1);
+ dev_warn(&udev->dev,
+ "%dmA is over %umA budget for port %d!\n",
+ delta, hub->mA_per_port, port1);
remaining -= delta;
}
if (remaining < 0) {
* 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
+ * usb_reset_and_verify_device() encounters changed descriptors (as from
* a firmware download)
* caller already locked the hub
*/
struct usb_device *hdev = hub->hdev;
struct device *hub_dev = hub->intfdev;
struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
- u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
+ unsigned wHubCharacteristics =
+ le16_to_cpu(hub->descriptor->wHubCharacteristics);
+ struct usb_device *udev;
int status, i;
-
+
dev_dbg (hub_dev,
"port %d, status %04x, change %04x, %s\n",
port1, portstatus, portchange, portspeed (portstatus));
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;
+ portchange &= ~(USB_PORT_STAT_C_CONNECTION |
+ USB_PORT_STAT_C_ENABLE);
#endif
- if (portchange & USB_PORT_STAT_C_CONNECTION) {
+ /* Try to resuscitate an existing device */
+ udev = hdev->children[port1-1];
+ if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
+ udev->state != USB_STATE_NOTATTACHED) {
+ usb_lock_device(udev);
+ if (portstatus & USB_PORT_STAT_ENABLE) {
+ status = 0; /* Nothing to do */
+
+#ifdef CONFIG_USB_SUSPEND
+ } else if (udev->state == USB_STATE_SUSPENDED &&
+ udev->persist_enabled) {
+ /* For a suspended device, treat this as a
+ * remote wakeup event.
+ */
+ if (udev->do_remote_wakeup)
+ status = remote_wakeup(udev);
+
+ /* Otherwise leave it be; devices can't tell the
+ * difference between suspended and disabled.
+ */
+ else
+ status = 0;
+#endif
+
+ } else {
+ status = -ENODEV; /* Don't resuscitate */
+ }
+ usb_unlock_device(udev);
+
+ if (status == 0) {
+ clear_bit(port1, hub->change_bits);
+ return;
+ }
+ }
+
+ /* Disconnect any existing devices under this port */
+ if (udev)
+ usb_disconnect(&hdev->children[port1-1]);
+ clear_bit(port1, hub->change_bits);
+
+ if (portchange & (USB_PORT_STAT_C_CONNECTION |
+ USB_PORT_STAT_C_ENABLE)) {
status = hub_port_debounce(hub, port1);
if (status < 0) {
if (printk_ratelimit())
- dev_err (hub_dev, "connect-debounce failed, "
+ dev_err(hub_dev, "connect-debounce failed, "
"port %d disabled\n", port1);
- goto done;
+ portstatus &= ~USB_PORT_STAT_CONNECTION;
+ } else {
+ portstatus = status;
}
- portstatus = status;
}
- /* Return now if nothing is connected */
+ /* Return now if debouncing failed or nothing is connected */
if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
/* maybe switch power back on (e.g. root hub was reset) */
if ((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;
}
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->speed = USB_SPEED_UNKNOWN;
udev->bus_mA = hub->mA_per_port;
udev->level = hdev->level + 1;
+ udev->wusb = hub_is_wusb(hub);
/* set the address */
choose_address(udev);
loop_disable:
hub_port_disable(hub, port1, 1);
loop:
- ep0_reinit(udev);
+ usb_ep0_reinit(udev);
release_address(udev);
usb_put_dev(udev);
if ((status == -ENOTCONN) || (status == -ENOTSUPP))
break;
}
- dev_err(hub_dev, "unable to enumerate USB device on port %d\n", port1);
+ if (hub->hdev->parent ||
+ !hcd->driver->port_handed_over ||
+ !(hcd->driver->port_handed_over)(hcd, port1))
+ dev_err(hub_dev, "unable to enumerate USB device on port %d\n",
+ port1);
done:
hub_port_disable(hub, port1, 1);
/* If the hub has died, clean up after it */
if (hdev->state == USB_STATE_NOTATTACHED) {
hub->error = -ENODEV;
- hub_stop(hub);
+ hub_quiesce(hub, HUB_DISCONNECT);
goto loop;
}
dev_dbg (hub_dev, "resetting for error %d\n",
hub->error);
- ret = usb_reset_composite_device(hdev, intf);
+ ret = usb_reset_device(hdev);
if (ret) {
dev_dbg (hub_dev,
"error resetting hub: %d\n", ret);
continue;
connect_change = test_bit(i, hub->change_bits);
if (!test_and_clear_bit(i, hub->event_bits) &&
- !connect_change && !hub->activating)
+ !connect_change)
continue;
ret = hub_port_status(hub, i,
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);
}
if (portchange & USB_PORT_STAT_C_SUSPEND) {
+ struct usb_device *udev;
+
clear_port_feature(hdev, i,
USB_PORT_FEAT_C_SUSPEND);
- if (hdev->children[i-1]) {
+ udev = hdev->children[i-1];
+ if (udev) {
+ usb_lock_device(udev);
ret = remote_wakeup(hdev->
children[i-1]);
+ usb_unlock_device(udev);
if (ret < 0)
connect_change = 1;
} else {
i);
clear_port_feature(hdev, i,
USB_PORT_FEAT_C_OVER_CURRENT);
- hub_power_on(hub);
+ hub_power_on(hub, true);
}
if (portchange & USB_PORT_STAT_C_RESET) {
dev_dbg (hub_dev, "overcurrent change\n");
msleep(500); /* Cool down */
clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
- hub_power_on(hub);
+ hub_power_on(hub, true);
}
}
- hub->activating = 0;
-
loop_autopm:
/* Allow autosuspend if we're not going to run again */
if (list_empty(&hub->event_list))
}
/**
- * usb_reset_device - perform a USB port reset to reinitialize a device
+ * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
* @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
*
* WARNING - don't use this routine to reset a composite device
* (one with multiple interfaces owned by separate drivers)!
- * Use usb_reset_composite_device() instead.
+ * Use usb_reset_device() instead.
*
* Do a port reset, reassign the device's address, and establish its
* former operating configuration. If the reset fails, or the device's
* holding the device lock because these tasks should always call
* usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
*/
-int usb_reset_device(struct usb_device *udev)
+static int usb_reset_and_verify_device(struct usb_device *udev)
{
struct usb_device *parent_hdev = udev->parent;
struct usb_hub *parent_hub;
if (!parent_hdev) {
/* this requires hcd-specific logic; see OHCI hc_restart() */
- dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
+ dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
return -EISDIR;
}
parent_hub = hdev_to_hub(parent_hdev);
/* ep0 maxpacket size may change; let the HCD know about it.
* Other endpoints will be handled by re-enumeration. */
- ep0_reinit(udev);
+ usb_ep0_reinit(udev);
ret = hub_port_init(parent_hub, udev, port1, i);
if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
break;
hub_port_logical_disconnect(parent_hub, port1);
return -ENODEV;
}
-EXPORT_SYMBOL_GPL(usb_reset_device);
/**
- * usb_reset_composite_device - warn interface drivers and perform a USB port reset
+ * usb_reset_device - warn interface drivers and perform a USB port reset
* @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
- * @iface: interface bound to the driver making the request (optional)
*
* Warns all drivers bound to registered interfaces (using their pre_reset
* method), performs the port reset, and then lets the drivers know that
* the reset is over (using their post_reset method).
*
- * Return value is the same as for usb_reset_device().
+ * Return value is the same as for usb_reset_and_verify_device().
*
* 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().
+ *
+ * If an interface is currently being probed or disconnected, we assume
+ * its driver knows how to handle resets. For all other interfaces,
+ * if the driver doesn't have pre_reset and post_reset methods then
+ * we attempt to unbind it and rebind afterward.
*/
-int usb_reset_composite_device(struct usb_device *udev,
- struct usb_interface *iface)
+int usb_reset_device(struct usb_device *udev)
{
int ret;
int i;
/* Prevent autosuspend during the reset */
usb_autoresume_device(udev);
- if (iface && iface->condition != USB_INTERFACE_BINDING)
- iface = NULL;
-
if (config) {
for (i = 0; i < config->desc.bNumInterfaces; ++i) {
struct usb_interface *cintf = config->interface[i];
struct usb_driver *drv;
+ int unbind = 0;
if (cintf->dev.driver) {
drv = to_usb_driver(cintf->dev.driver);
- if (drv->pre_reset)
- (drv->pre_reset)(cintf);
- /* FIXME: Unbind if pre_reset returns an error or isn't defined */
+ if (drv->pre_reset && drv->post_reset)
+ unbind = (drv->pre_reset)(cintf);
+ else if (cintf->condition ==
+ USB_INTERFACE_BOUND)
+ unbind = 1;
+ if (unbind)
+ usb_forced_unbind_intf(cintf);
}
}
}
- ret = usb_reset_device(udev);
+ ret = usb_reset_and_verify_device(udev);
if (config) {
for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
struct usb_interface *cintf = config->interface[i];
struct usb_driver *drv;
+ int rebind = cintf->needs_binding;
- if (cintf->dev.driver) {
+ if (!rebind && cintf->dev.driver) {
drv = to_usb_driver(cintf->dev.driver);
if (drv->post_reset)
- (drv->post_reset)(cintf);
- /* FIXME: Unbind if post_reset returns an error or isn't defined */
+ rebind = (drv->post_reset)(cintf);
+ else if (cintf->condition ==
+ USB_INTERFACE_BOUND)
+ rebind = 1;
}
+ if (ret == 0 && rebind)
+ usb_rebind_intf(cintf);
}
}
usb_autosuspend_device(udev);
return ret;
}
-EXPORT_SYMBOL_GPL(usb_reset_composite_device);
+EXPORT_SYMBOL_GPL(usb_reset_device);
+
+
+/**
+ * usb_queue_reset_device - Reset a USB device from an atomic context
+ * @iface: USB interface belonging to the device to reset
+ *
+ * This function can be used to reset a USB device from an atomic
+ * context, where usb_reset_device() won't work (as it blocks).
+ *
+ * Doing a reset via this method is functionally equivalent to calling
+ * usb_reset_device(), except for the fact that it is delayed to a
+ * workqueue. This means that any drivers bound to other interfaces
+ * might be unbound, as well as users from usbfs in user space.
+ *
+ * Corner cases:
+ *
+ * - Scheduling two resets at the same time from two different drivers
+ * attached to two different interfaces of the same device is
+ * possible; depending on how the driver attached to each interface
+ * handles ->pre_reset(), the second reset might happen or not.
+ *
+ * - If a driver is unbound and it had a pending reset, the reset will
+ * be cancelled.
+ *
+ * - This function can be called during .probe() or .disconnect()
+ * times. On return from .disconnect(), any pending resets will be
+ * cancelled.
+ *
+ * There is no no need to lock/unlock the @reset_ws as schedule_work()
+ * does its own.
+ *
+ * NOTE: We don't do any reference count tracking because it is not
+ * needed. The lifecycle of the work_struct is tied to the
+ * usb_interface. Before destroying the interface we cancel the
+ * work_struct, so the fact that work_struct is queued and or
+ * running means the interface (and thus, the device) exist and
+ * are referenced.
+ */
+void usb_queue_reset_device(struct usb_interface *iface)
+{
+ schedule_work(&iface->reset_ws);
+}
+EXPORT_SYMBOL_GPL(usb_queue_reset_device);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff