diff options
Diffstat (limited to 'drivers/usb/core/driver.c')
| -rw-r--r-- | drivers/usb/core/driver.c | 930 |
1 files changed, 434 insertions, 496 deletions
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index 60a45f1e3a67..f3c233806fa3 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -25,7 +25,7 @@ #include <linux/device.h> #include <linux/usb.h> #include <linux/usb/quirks.h> -#include <linux/workqueue.h> +#include <linux/pm_runtime.h> #include "hcd.h" #include "usb.h" @@ -221,7 +221,7 @@ static int usb_probe_device(struct device *dev) { struct usb_device_driver *udriver = to_usb_device_driver(dev->driver); struct usb_device *udev = to_usb_device(dev); - int error = -ENODEV; + int error = 0; dev_dbg(dev, "%s\n", __func__); @@ -230,18 +230,23 @@ static int usb_probe_device(struct device *dev) /* The device should always appear to be in use * unless the driver suports autosuspend. */ - udev->pm_usage_cnt = !(udriver->supports_autosuspend); + if (!udriver->supports_autosuspend) + error = usb_autoresume_device(udev); - error = udriver->probe(udev); + if (!error) + error = udriver->probe(udev); return error; } /* called from driver core with dev locked */ static int usb_unbind_device(struct device *dev) { + struct usb_device *udev = to_usb_device(dev); struct usb_device_driver *udriver = to_usb_device_driver(dev->driver); - udriver->disconnect(to_usb_device(dev)); + udriver->disconnect(udev); + if (!udriver->supports_autosuspend) + usb_autosuspend_device(udev); return 0; } @@ -274,60 +279,62 @@ static int usb_probe_interface(struct device *dev) intf->needs_binding = 0; if (usb_device_is_owned(udev)) - return -ENODEV; + return error; if (udev->authorized == 0) { dev_err(&intf->dev, "Device is not authorized for usage\n"); - return -ENODEV; + return error; } id = usb_match_id(intf, driver->id_table); if (!id) id = usb_match_dynamic_id(intf, driver); - if (id) { - dev_dbg(dev, "%s - got id\n", __func__); - - error = usb_autoresume_device(udev); - if (error) - return error; + if (!id) + return error; - /* Interface "power state" doesn't correspond to any hardware - * state whatsoever. We use it to record when it's bound to - * a driver that may start I/0: it's not frozen/quiesced. - */ - mark_active(intf); - intf->condition = USB_INTERFACE_BINDING; + dev_dbg(dev, "%s - got id\n", __func__); - /* The interface should always appear to be in use - * unless the driver suports autosuspend. - */ - atomic_set(&intf->pm_usage_cnt, !driver->supports_autosuspend); - - /* Carry out a deferred switch to altsetting 0 */ - if (intf->needs_altsetting0) { - error = usb_set_interface(udev, intf->altsetting[0]. - desc.bInterfaceNumber, 0); - if (error < 0) - goto err; + error = usb_autoresume_device(udev); + if (error) + return error; - intf->needs_altsetting0 = 0; - } + intf->condition = USB_INTERFACE_BINDING; - error = driver->probe(intf, id); - if (error) + /* Bound interfaces are initially active. They are + * runtime-PM-enabled only if the driver has autosuspend support. + * They are sensitive to their children's power states. + */ + pm_runtime_set_active(dev); + pm_suspend_ignore_children(dev, false); + if (driver->supports_autosuspend) + pm_runtime_enable(dev); + + /* Carry out a deferred switch to altsetting 0 */ + if (intf->needs_altsetting0) { + error = usb_set_interface(udev, intf->altsetting[0]. + desc.bInterfaceNumber, 0); + if (error < 0) goto err; - - intf->condition = USB_INTERFACE_BOUND; - usb_autosuspend_device(udev); + intf->needs_altsetting0 = 0; } + error = driver->probe(intf, id); + if (error) + goto err; + + intf->condition = USB_INTERFACE_BOUND; + usb_autosuspend_device(udev); return error; -err: - mark_quiesced(intf); + err: intf->needs_remote_wakeup = 0; intf->condition = USB_INTERFACE_UNBOUND; usb_cancel_queued_reset(intf); + + /* Unbound interfaces are always runtime-PM-disabled and -suspended */ + pm_runtime_disable(dev); + pm_runtime_set_suspended(dev); + usb_autosuspend_device(udev); return error; } @@ -377,9 +384,17 @@ static int usb_unbind_interface(struct device *dev) usb_set_intfdata(intf, NULL); intf->condition = USB_INTERFACE_UNBOUND; - mark_quiesced(intf); intf->needs_remote_wakeup = 0; + /* Unbound interfaces are always runtime-PM-disabled and -suspended */ + pm_runtime_disable(dev); + pm_runtime_set_suspended(dev); + + /* Undo any residual pm_autopm_get_interface_* calls */ + for (r = atomic_read(&intf->pm_usage_cnt); r > 0; --r) + usb_autopm_put_interface_no_suspend(intf); + atomic_set(&intf->pm_usage_cnt, 0); + if (!error) usb_autosuspend_device(udev); @@ -410,7 +425,6 @@ int usb_driver_claim_interface(struct usb_driver *driver, struct usb_interface *iface, void *priv) { struct device *dev = &iface->dev; - struct usb_device *udev = interface_to_usbdev(iface); int retval = 0; if (dev->driver) @@ -420,11 +434,16 @@ int usb_driver_claim_interface(struct usb_driver *driver, usb_set_intfdata(iface, priv); iface->needs_binding = 0; - usb_pm_lock(udev); iface->condition = USB_INTERFACE_BOUND; - mark_active(iface); - atomic_set(&iface->pm_usage_cnt, !driver->supports_autosuspend); - usb_pm_unlock(udev); + + /* Bound interfaces are initially active. They are + * runtime-PM-enabled only if the driver has autosuspend support. + * They are sensitive to their children's power states. + */ + pm_runtime_set_active(dev); + pm_suspend_ignore_children(dev, false); + if (driver->supports_autosuspend) + pm_runtime_enable(dev); /* if interface was already added, bind now; else let * the future device_add() bind it, bypassing probe() @@ -470,10 +489,10 @@ void usb_driver_release_interface(struct usb_driver *driver, if (device_is_registered(dev)) { device_release_driver(dev); } else { - down(&dev->sem); + device_lock(dev); usb_unbind_interface(dev); dev->driver = NULL; - up(&dev->sem); + device_unlock(dev); } } EXPORT_SYMBOL_GPL(usb_driver_release_interface); @@ -691,9 +710,6 @@ static int usb_uevent(struct device *dev, struct kobj_uevent_env *env) { struct usb_device *usb_dev; - /* driver is often null here; dev_dbg() would oops */ - pr_debug("usb %s: uevent\n", dev_name(dev)); - if (is_usb_device(dev)) { usb_dev = to_usb_device(dev); } else if (is_usb_interface(dev)) { @@ -705,6 +721,7 @@ static int usb_uevent(struct device *dev, struct kobj_uevent_env *env) } if (usb_dev->devnum < 0) { + /* driver is often null here; dev_dbg() would oops */ pr_debug("usb %s: already deleted?\n", dev_name(dev)); return -ENODEV; } @@ -983,7 +1000,6 @@ static void do_unbind_rebind(struct usb_device *udev, int action) } } -/* Caller has locked udev's pm_mutex */ static int usb_suspend_device(struct usb_device *udev, pm_message_t msg) { struct usb_device_driver *udriver; @@ -1007,7 +1023,6 @@ static int usb_suspend_device(struct usb_device *udev, pm_message_t msg) return status; } -/* Caller has locked udev's pm_mutex */ static int usb_resume_device(struct usb_device *udev, pm_message_t msg) { struct usb_device_driver *udriver; @@ -1022,6 +1037,14 @@ static int usb_resume_device(struct usb_device *udev, pm_message_t msg) goto done; } + /* Non-root devices on a full/low-speed bus must wait for their + * companion high-speed root hub, in case a handoff is needed. + */ + if (!(msg.event & PM_EVENT_AUTO) && udev->parent && + udev->bus->hs_companion) + device_pm_wait_for_dev(&udev->dev, + &udev->bus->hs_companion->root_hub->dev); + if (udev->quirks & USB_QUIRK_RESET_RESUME) udev->reset_resume = 1; @@ -1033,27 +1056,20 @@ static int usb_resume_device(struct usb_device *udev, pm_message_t msg) return status; } -/* Caller has locked intf's usb_device's pm mutex */ static int usb_suspend_interface(struct usb_device *udev, struct usb_interface *intf, pm_message_t msg) { struct usb_driver *driver; int status = 0; - /* with no hardware, USB interfaces only use FREEZE and ON states */ - if (udev->state == USB_STATE_NOTATTACHED || !is_active(intf)) - goto done; - - /* This can happen; see usb_driver_release_interface() */ - if (intf->condition == USB_INTERFACE_UNBOUND) + if (udev->state == USB_STATE_NOTATTACHED || + intf->condition == USB_INTERFACE_UNBOUND) goto done; driver = to_usb_driver(intf->dev.driver); if (driver->suspend) { status = driver->suspend(intf, msg); - if (status == 0) - mark_quiesced(intf); - else if (!(msg.event & PM_EVENT_AUTO)) + if (status && !(msg.event & PM_EVENT_AUTO)) dev_err(&intf->dev, "%s error %d\n", "suspend", status); } else { @@ -1061,7 +1077,6 @@ static int usb_suspend_interface(struct usb_device *udev, intf->needs_binding = 1; dev_warn(&intf->dev, "no %s for driver %s?\n", "suspend", driver->name); - mark_quiesced(intf); } done: @@ -1069,14 +1084,13 @@ static int usb_suspend_interface(struct usb_device *udev, return status; } -/* Caller has locked intf's usb_device's pm_mutex */ static int usb_resume_interface(struct usb_device *udev, struct usb_interface *intf, pm_message_t msg, int reset_resume) { struct usb_driver *driver; int status = 0; - if (udev->state == USB_STATE_NOTATTACHED || is_active(intf)) + if (udev->state == USB_STATE_NOTATTACHED) goto done; /* Don't let autoresume interfere with unbinding */ @@ -1127,90 +1141,11 @@ static int usb_resume_interface(struct usb_device *udev, done: dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status); - if (status == 0 && intf->condition == USB_INTERFACE_BOUND) - mark_active(intf); /* Later we will unbind the driver and/or reprobe, if necessary */ return status; } -#ifdef CONFIG_USB_SUSPEND - -/* Internal routine to check whether we may autosuspend a device. */ -static int autosuspend_check(struct usb_device *udev, int reschedule) -{ - int i; - struct usb_interface *intf; - unsigned long suspend_time, j; - - /* For autosuspend, fail fast if anything is in use or autosuspend - * is disabled. Also fail if any interfaces require remote wakeup - * but it isn't available. - */ - if (udev->pm_usage_cnt > 0) - return -EBUSY; - if (udev->autosuspend_delay < 0 || udev->autosuspend_disabled) - return -EPERM; - - suspend_time = udev->last_busy + udev->autosuspend_delay; - if (udev->actconfig) { - for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { - intf = udev->actconfig->interface[i]; - if (!is_active(intf)) - continue; - if (atomic_read(&intf->pm_usage_cnt) > 0) - return -EBUSY; - if (intf->needs_remote_wakeup && - !udev->do_remote_wakeup) { - dev_dbg(&udev->dev, "remote wakeup needed " - "for autosuspend\n"); - return -EOPNOTSUPP; - } - - /* Don't allow autosuspend if the device will need - * a reset-resume and any of its interface drivers - * doesn't include support. - */ - if (udev->quirks & USB_QUIRK_RESET_RESUME) { - struct usb_driver *driver; - - driver = to_usb_driver(intf->dev.driver); - if (!driver->reset_resume || - intf->needs_remote_wakeup) - return -EOPNOTSUPP; - } - } - } - - /* If everything is okay but the device hasn't been idle for long - * enough, queue a delayed autosuspend request. If the device - * _has_ been idle for long enough and the reschedule flag is set, - * likewise queue a delayed (1 second) autosuspend request. - */ - j = jiffies; - if (time_before(j, suspend_time)) - reschedule = 1; - else - suspend_time = j + HZ; - if (reschedule) { - if (!timer_pending(&udev->autosuspend.timer)) { - queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend, - round_jiffies_up_relative(suspend_time - j)); - } - return -EAGAIN; - } - return 0; -} - -#else - -static inline int autosuspend_check(struct usb_device *udev, int reschedule) -{ - return 0; -} - -#endif /* CONFIG_USB_SUSPEND */ - /** * usb_suspend_both - suspend a USB device and its interfaces * @udev: the usb_device to suspend @@ -1222,27 +1157,12 @@ static inline int autosuspend_check(struct usb_device *udev, int reschedule) * all the interfaces which were suspended are resumed so that they remain * in the same state as the device. * - * If an autosuspend is in progress the routine checks first to make sure - * that neither the device itself or any of its active interfaces is in use - * (pm_usage_cnt is greater than 0). If they are, the autosuspend fails. - * - * If the suspend succeeds, the routine recursively queues an autosuspend - * request for @udev's parent device, thereby propagating the change up - * the device tree. If all of the parent's children are now suspended, - * the parent will autosuspend in turn. - * - * The suspend method calls are subject to mutual exclusion under control - * of @udev's pm_mutex. Many of these calls are also under the protection - * of @udev's device lock (including all requests originating outside the - * USB subsystem), but autosuspend requests generated by a child device or - * interface driver may not be. Usbcore will insure that the method calls - * do not arrive during bind, unbind, or reset operations. However, drivers - * must be prepared to handle suspend calls arriving at unpredictable times. - * The only way to block such calls is to do an autoresume (preventing - * autosuspends) while holding @udev's device lock (preventing outside - * suspends). - * - * The caller must hold @udev->pm_mutex. + * Autosuspend requests originating from a child device or an interface + * driver may be made without the protection of @udev's device lock, but + * all other suspend calls will hold the lock. Usbcore will insure that + * method calls do not arrive during bind, unbind, or reset operations. + * However drivers must be prepared to handle suspend calls arriving at + * unpredictable times. * * This routine can run only in process context. */ @@ -1251,20 +1171,11 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) int status = 0; int i = 0; struct usb_interface *intf; - struct usb_device *parent = udev->parent; if (udev->state == USB_STATE_NOTATTACHED || udev->state == USB_STATE_SUSPENDED) goto done; - udev->do_remote_wakeup = device_may_wakeup(&udev->dev); - - if (msg.event & PM_EVENT_AUTO) { - status = autosuspend_check(udev, 0); - if (status < 0) - goto done; - } - /* Suspend all the interfaces and then udev itself */ if (udev->actconfig) { for (; i < udev->actconfig->desc.bNumInterfaces; i++) { @@ -1279,35 +1190,21 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) /* If the suspend failed, resume interfaces that did get suspended */ if (status != 0) { - pm_message_t msg2; - - msg2.event = msg.event ^ (PM_EVENT_SUSPEND | PM_EVENT_RESUME); + msg.event ^= (PM_EVENT_SUSPEND | PM_EVENT_RESUME); while (--i >= 0) { intf = udev->actconfig->interface[i]; - usb_resume_interface(udev, intf, msg2, 0); + usb_resume_interface(udev, intf, msg, 0); } - /* Try another autosuspend when the interfaces aren't busy */ - if (msg.event & PM_EVENT_AUTO) - autosuspend_check(udev, status == -EBUSY); - - /* If the suspend succeeded then prevent any more URB submissions, - * flush any outstanding URBs, and propagate the suspend up the tree. + /* If the suspend succeeded then prevent any more URB submissions + * and flush any outstanding URBs. */ } else { - cancel_delayed_work(&udev->autosuspend); udev->can_submit = 0; for (i = 0; i < 16; ++i) { usb_hcd_flush_endpoint(udev, udev->ep_out[i]); usb_hcd_flush_endpoint(udev, udev->ep_in[i]); } - - /* If this is just a FREEZE or a PRETHAW, udev might - * not really be suspended. Only true suspends get - * propagated up the device tree. - */ - if (parent && udev->state == USB_STATE_SUSPENDED) - usb_autosuspend_device(parent); } done: @@ -1324,23 +1221,12 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) * the resume method for @udev and then calls the resume methods for all * the interface drivers in @udev. * - * Before starting the resume, the routine calls itself recursively for - * the parent device of @udev, thereby propagating the change up the device - * tree and assuring that @udev will be able to resume. If the parent is - * unable to resume successfully, the routine fails. - * - * The resume method calls are subject to mutual exclusion under control - * of @udev's pm_mutex. Many of these calls are also under the protection - * of @udev's device lock (including all requests originating outside the - * USB subsystem), but autoresume requests generated by a child device or - * interface driver may not be. Usbcore will insure that the method calls - * do not arrive during bind, unbind, or reset operations. However, drivers - * must be prepared to handle resume calls arriving at unpredictable times. - * The only way to block such calls is to do an autoresume (preventing - * other autoresumes) while holding @udev's device lock (preventing outside - * resumes). - * - * The caller must hold @udev->pm_mutex. + * Autoresume requests originating from a child device or an interface + * driver may be made without the protection of @udev's device lock, but + * all other resume calls will hold the lock. Usbcore will insure that + * method calls do not arrive during bind, unbind, or reset operations. + * However drivers must be prepared to handle resume calls arriving at + * unpredictable times. * * This routine can run only in process context. */ @@ -1349,48 +1235,18 @@ static int usb_resume_both(struct usb_device *udev, pm_message_t msg) int status = 0; int i; struct usb_interface *intf; - struct usb_device *parent = udev->parent; - cancel_delayed_work(&udev->autosuspend); if (udev->state == USB_STATE_NOTATTACHED) { status = -ENODEV; goto done; } udev->can_submit = 1; - /* Propagate the resume up the tree, if necessary */ - if (udev->state == USB_STATE_SUSPENDED) { - if (parent) { - status = usb_autoresume_device(parent); - if (status == 0) { - status = usb_resume_device(udev, msg); - if (status || udev->state == - USB_STATE_NOTATTACHED) { - usb_autosuspend_device(parent); - - /* It's possible usb_resume_device() - * failed after the port was - * unsuspended, causing udev to be - * logically disconnected. We don't - * want usb_disconnect() to autosuspend - * the parent again, so tell it that - * udev disconnected while still - * suspended. */ - if (udev->state == - USB_STATE_NOTATTACHED) - udev->discon_suspended = 1; - } - } - } else { - - /* We can't progagate beyond the USB subsystem, - * so if a root hub's controller is suspended - * then we're stuck. */ - status = usb_resume_device(udev, msg); - } - } else if (udev->reset_resume) + /* Resume the device */ + if (udev->state == USB_STATE_SUSPENDED || udev->reset_resume) status = usb_resume_device(udev, msg); + /* Resume the interfaces */ if (status == 0 && udev->actconfig) { for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { intf = udev->actconfig->interface[i]; @@ -1406,55 +1262,94 @@ static int usb_resume_both(struct usb_device *udev, pm_message_t msg) return status; } -#ifdef CONFIG_USB_SUSPEND +/* The device lock is held by the PM core */ +int usb_suspend(struct device *dev, pm_message_t msg) +{ + struct usb_device *udev = to_usb_device(dev); -/* Internal routine to adjust a device's usage counter and change - * its autosuspend state. - */ -static int usb_autopm_do_device(struct usb_device *udev, int inc_usage_cnt) + do_unbind_rebind(udev, DO_UNBIND); + udev->do_remote_wakeup = device_may_wakeup(&udev->dev); + return usb_suspend_both(udev, msg); +} + +/* The device lock is held by the PM core */ +int usb_resume(struct device *dev, pm_message_t msg) { - int status = 0; + struct usb_device *udev = to_usb_device(dev); + int status; - usb_pm_lock(udev); - udev->pm_usage_cnt += inc_usage_cnt; - WARN_ON(udev->pm_usage_cnt < 0); - if (inc_usage_cnt) - udev->last_busy = jiffies; - if (inc_usage_cnt >= 0 && udev->pm_usage_cnt > 0) { - if (udev->state == USB_STATE_SUSPENDED) - status = usb_resume_both(udev, PMSG_AUTO_RESUME); - if (status != 0) - udev->pm_usage_cnt -= inc_usage_cnt; - else if (inc_usage_cnt) + /* For PM complete calls, all we do is rebind interfaces */ + if (msg.event == PM_EVENT_ON) { + if (udev->state != USB_STATE_NOTATTACHED) + do_unbind_rebind(udev, DO_REBIND); + status = 0; + + /* For all other calls, take the device back to full power and + * tell the PM core in case it was autosuspended previously. + */ + } else { + status = usb_resume_both(udev, msg); + if (status == 0) { + pm_runtime_disable(dev); + pm_runtime_set_active(dev); + pm_runtime_enable(dev); udev->last_busy = jiffies; - } else if (inc_usage_cnt <= 0 && udev->pm_usage_cnt <= 0) { - status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND); + } } - usb_pm_unlock(udev); + + /* Avoid PM error messages for devices disconnected while suspended + * as we'll display regular disconnect messages just a bit later. + */ + if (status == -ENODEV) + status = 0; return status; } -/* usb_autosuspend_work - callback routine to autosuspend a USB device */ -void usb_autosuspend_work(struct work_struct *work) -{ - struct usb_device *udev = - container_of(work, struct usb_device, autosuspend.work); +#endif /* CONFIG_PM */ - usb_autopm_do_device(udev, 0); +#ifdef CONFIG_USB_SUSPEND + +/** + * usb_enable_autosuspend - allow a USB device to be autosuspended + * @udev: the USB device which may be autosuspended + * + * This routine allows @udev to be autosuspended. An autosuspend won't + * take place until the autosuspend_delay has elapsed and all the other + * necessary conditions are satisfied. + * + * The caller must hold @udev's device lock. + */ +int usb_enable_autosuspend(struct usb_device *udev) +{ + if (udev->autosuspend_disabled) { + udev->autosuspend_disabled = 0; + usb_autosuspend_device(udev); + } + return 0; } +EXPORT_SYMBOL_GPL(usb_enable_autosuspend); -/* usb_autoresume_work - callback routine to autoresume a USB device */ -void usb_autoresume_work(struct work_struct *work) +/** + * usb_disable_autosuspend - prevent a USB device from being autosuspended + * @udev: the USB device which may not be autosuspended + * + * This routine prevents @udev from being autosuspended and wakes it up + * if it is already autosuspended. + * + * The caller must hold @udev's device lock. + */ +int usb_disable_autosuspend(struct usb_device *udev) { - struct usb_device *udev = - container_of(work, struct usb_device, autoresume); + int rc = 0; - /* Wake it up, let the drivers do their thing, and then put it - * back to sleep. - */ - if (usb_autopm_do_device(udev, 1) == 0) - usb_autopm_do_device(udev, -1); + if (!udev->autosuspend_disabled) { + rc = usb_autoresume_device(udev); + if (rc == 0) + udev->autosuspend_disabled = 1; + } + return rc; } +EXPORT_SYMBOL_GPL(usb_disable_autosuspend); /** * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces @@ -1464,15 +1359,11 @@ void usb_autoresume_work(struct work_struct *work) * @udev and wants to allow it to autosuspend. Examples would be when * @udev's device file in usbfs is closed or after a configuration change. * - * @udev's usage counter is decremented. If it or any of the usage counters - * for an active interface is greater than 0, no autosuspend request will be - * queued. (If an interface driver does not support autosuspend then its - * usage counter is permanently positive.) Furthermore, if an interface - * driver requires remote-wakeup capability during autosuspend but remote - * wakeup is disabled, the autosuspend will fail. + * @udev's usage counter is decremented; if it drops to 0 and all the + * interfaces are inactive then a delayed autosuspend will be attempted. + * The attempt may fail (see autosuspend_check()). * - * Often the caller will hold @udev's device lock, but this is not - * necessary. + * The caller must hold @udev's device lock. * * This routine can run only in process context. */ @@ -1480,9 +1371,11 @@ void usb_autosuspend_device(struct usb_device *udev) { int status; - status = usb_autopm_do_device(udev, -1); - dev_vdbg(&udev->dev, "%s: cnt %d\n", - __func__, udev->pm_usage_cnt); + udev->last_busy = jiffies; + status = pm_runtime_put_sync(&udev->dev); + dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n", + __func__, atomic_read(&udev->dev.power.usage_count), + status); } /** @@ -1492,17 +1385,22 @@ void usb_autosuspend_device(struct usb_device *udev) * This routine should be called when a core subsystem thinks @udev may * be ready to autosuspend. * - * @udev's usage counter left unchanged. If it or any of the usage counters - * for an active interface is greater than 0, or autosuspend is not allowed - * for any other reason, no autosuspend request will be queued. + * @udev's usage counter left unchanged. If it is 0 and all the interfaces + * are inactive then an autosuspend will be attempted. The attempt may + * fail or be delayed. + * + * The caller must hold @udev's device lock. * * This routine can run only in process context. */ void usb_try_autosuspend_device(struct usb_device *udev) { - usb_autopm_do_device(udev, 0); - dev_vdbg(&udev->dev, "%s: cnt %d\n", - __func__, udev->pm_usage_cnt); + int status; + + status = pm_runtime_idle(&udev->dev); + dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n", + __func__, atomic_read(&udev->dev.power.usage_count), + status); } /** @@ -1511,16 +1409,15 @@ void usb_try_autosuspend_device(struct usb_device *udev) * * This routine should be called when a core subsystem wants to use @udev * and needs to guarantee that it is not suspended. No autosuspend will - * occur until usb_autosuspend_device is called. (Note that this will not - * prevent suspend events originating in the PM core.) Examples would be - * when @udev's device file in usbfs is opened or when a remote-wakeup + * occur until usb_autosuspend_device() is called. (Note that this will + * not prevent suspend events originating in the PM core.) Examples would + * be when @udev's device file in usbfs is opened or when a remote-wakeup * request is received. * * @udev's usage counter is incremented to prevent subsequent autosuspends. * However if the autoresume fails then the usage counter is re-decremented. * - * Often the caller will hold @udev's device lock, but this is not - * necessary (and attempting it might cause deadlock). + * The caller must hold @udev's device lock. * * This routine can run only in process context. */ @@ -1528,42 +1425,14 @@ int usb_autoresume_device(struct usb_device *udev) { int status; - status = usb_autopm_do_device(udev, 1); - dev_vdbg(&udev->dev, "%s: status %d cnt %d\n", - __func__, status, udev->pm_usage_cnt); - return status; -} - -/* Internal routine to adjust an interface's usage counter and change - * its device's autosuspend state. - */ -static int usb_autopm_do_interface(struct usb_interface *intf, - int inc_usage_cnt) -{ - struct usb_device *udev = interface_to_usbdev(intf); - int status = 0; - - usb_pm_lock(udev); - if (intf->condition == USB_INTERFACE_UNBOUND) - status = -ENODEV; - else { - atomic_add(inc_usage_cnt, &intf->pm_usage_cnt); - udev->last_busy = jiffies; - if (inc_usage_cnt >= 0 && - atomic_read(&intf->pm_usage_cnt) > 0) { - if (udev->state == USB_STATE_SUSPENDED) - status = usb_resume_both(udev, - PMSG_AUTO_RESUME); - if (status != 0) - atomic_sub(inc_usage_cnt, &intf->pm_usage_cnt); - else - udev->last_busy = jiffies; - } else if (inc_usage_cnt <= 0 && - atomic_read(&intf->pm_usage_cnt) <= 0) { - status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND); - } - } - usb_pm_unlock(udev); + status = pm_runtime_get_sync(&udev->dev); + if (status < 0) + pm_runtime_put_sync(&udev->dev); + dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n", + __func__, atomic_read(&udev->dev.power.usage_count), + status); + if (status > 0) + status = 0; return status; } @@ -1577,34 +1446,25 @@ static int usb_autopm_do_interface(struct usb_interface *intf, * closed. * * The routine decrements @intf's usage counter. When the counter reaches - * 0, a delayed autosuspend request for @intf's device is queued. When - * the delay expires, if @intf->pm_usage_cnt is still <= 0 along with all - * the other usage counters for the sibling interfaces and @intf's - * usb_device, the device and all its interfaces will be autosuspended. - * - * Note that @intf->pm_usage_cnt is owned by the interface driver. The - * core will not change its value other than the increment and decrement - * in usb_autopm_get_interface and usb_autopm_put_interface. The driver - * may use this simple counter-oriented discipline or may set the value - * any way it likes. + * 0, a delayed autosuspend request for @intf's device is attempted. The + * attempt may fail (see autosuspend_check()). * * If the driver has set @intf->needs_remote_wakeup then autosuspend will * take place only if the device's remote-wakeup facility is enabled. * - * Suspend method calls queued by this routine can arrive at any time - * while @intf is resumed and its usage counter is equal to 0. They are - * not protected by the usb_device's lock but only by its pm_mutex. - * Drivers must provide their own synchronization. - * * This routine can run only in process context. */ void usb_autopm_put_interface(struct usb_interface *intf) { - int status; + struct usb_device *udev = interface_to_usbdev(intf); + int status; - status = usb_autopm_do_interface(intf, -1); - dev_vdbg(&intf->dev, "%s: status %d cnt %d\n", - __func__, status, atomic_read(&intf->pm_usage_cnt)); + udev->last_busy = jiffies; + atomic_dec(&intf->pm_usage_cnt); + status = pm_runtime_put_sync(&intf->dev); + dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n", + __func__, atomic_read(&intf->dev.power.usage_count), + status); } EXPORT_SYMBOL_GPL(usb_autopm_put_interface); @@ -1612,11 +1472,11 @@ EXPORT_SYMBOL_GPL(usb_autopm_put_interface); * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter * @intf: the usb_interface whose counter should be decremented * - * This routine does essentially the same thing as - * usb_autopm_put_interface(): it decrements @intf's usage counter and - * queues a delayed autosuspend request if the counter is <= 0. The - * difference is that it does not acquire the device's pm_mutex; - * callers must handle all synchronization issues themselves. + * This routine does much the same thing as usb_autopm_put_interface(): + * It decrements @intf's usage counter and schedules a delayed + * autosuspend request if the counter is <= 0. The difference is that it + * does not perform any synchronization; callers should hold a private + * lock and handle all synchronization issues themselves. * * Typically a driver would call this routine during an URB's completion * handler, if no more URBs were pending. @@ -1626,28 +1486,58 @@ EXPORT_SYMBOL_GPL(usb_autopm_put_interface); void usb_autopm_put_interface_async(struct usb_interface *intf) { struct usb_device *udev = interface_to_usbdev(intf); + unsigned long last_busy; int status = 0; - if (intf->condition == USB_INTERFACE_UNBOUND) { - status = -ENODEV; - } else { - udev->last_busy = jiffies; - atomic_dec(&intf->pm_usage_cnt); - if (udev->autosuspend_disabled || udev->autosuspend_delay < 0) - status = -EPERM; - else if (atomic_read(&intf->pm_usage_cnt) <= 0 && - !timer_pending(&udev->autosuspend.timer)) { - queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend, + last_busy = udev->last_busy; + udev->last_busy = jiffies; + atomic_dec(&intf->pm_usage_cnt); + pm_runtime_put_noidle(&intf->dev); + + if (!udev->autosuspend_disabled) { + /* Optimization: Don't schedule a delayed autosuspend if + * the timer is already running and the expiration time + * wouldn't change. + * + * We have to use the interface's timer. Attempts to + * schedule a suspend for the device would fail because + * the interface is still active. + */ + if (intf->dev.power.timer_expires == 0 || + round_jiffies_up(last_busy) != + round_jiffies_up(jiffies)) { + status = pm_schedule_suspend(&intf->dev, + jiffies_to_msecs( round_jiffies_up_relative( - udev->autosuspend_delay)); + udev->autosuspend_delay))); } } - dev_vdbg(&intf->dev, "%s: status %d cnt %d\n", - __func__, status, atomic_read(&intf->pm_usage_cnt)); + dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n", + __func__, atomic_read(&intf->dev.power.usage_count), + status); } EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async); /** + * usb_autopm_put_interface_no_suspend - decrement a USB interface's PM-usage counter + * @intf: the usb_interface whose counter should be decremented + * + * This routine decrements @intf's usage counter but does not carry out an + * autosuspend. + * + * This routine can run in atomic context. + */ +void usb_autopm_put_interface_no_suspend(struct usb_interface *intf) +{ + struct usb_device *udev = interface_to_usbdev(intf); + + udev->last_busy = jiffies; + atomic_dec(&intf->pm_usage_cnt); + pm_runtime_put_noidle(&intf->dev); +} +EXPORT_SYMBOL_GPL(usb_autopm_put_interface_no_suspend); + +/** * usb_autopm_get_interface - increment a USB interface's PM-usage counter * @intf: the usb_interface whose counter should be incremented * @@ -1659,25 +1549,8 @@ EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async); * or @intf is unbound. A typical example would be a character-device * driver when its device file is opened. * - * - * The routine increments @intf's usage counter. (However if the - * autoresume fails then the counter is re-decremented.) So long as the - * counter is greater than 0, autosuspend will not be allowed for @intf - * or its usb_device. When the driver is finished using @intf it should - * call usb_autopm_put_interface() to decrement the usage counter and - * queue a delayed autosuspend request (if the counter is <= 0). - * - * - * Note that @intf->pm_usage_cnt is owned by the interface driver. The - * core will not change its value other than the increment and decrement - * in usb_autopm_get_interface and usb_autopm_put_interface. The driver - * may use this simple counter-oriented discipline or may set the value - * any way it likes. - * - * Resume method calls generated by this routine can arrive at any time - * while @intf is suspended. They are not protected by the usb_device's - * lock but only by its pm_mutex. Drivers must provide their own - * synchronization. + * @intf's usage counter is incremented to prevent subsequent autosuspends. + * However if the autoresume fails then the counter is re-decremented. * * This routine can run only in process context. */ @@ -1685,9 +1558,16 @@ int usb_autopm_get_interface(struct usb_interface *intf) { int status; - status = usb_autopm_do_interface(intf, 1); - dev_vdbg(&intf->dev, "%s: status %d cnt %d\n", - __func__, status, atomic_read(&intf->pm_usage_cnt)); + status = pm_runtime_get_sync(&intf->dev); + if (status < 0) + pm_runtime_put_sync(&intf->dev); + else + atomic_inc(&intf->pm_usage_cnt); + dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n", + __func__, atomic_read(&intf->dev.power.usage_count), + status); + if (status > 0) + status = 0; return status; } EXPORT_SYMBOL_GPL(usb_autopm_get_interface); @@ -1697,149 +1577,207 @@ EXPORT_SYMBOL_GPL(usb_autopm_get_interface); * @intf: the usb_interface whose counter should be incremented * * This routine does much the same thing as - * usb_autopm_get_interface(): it increments @intf's usage counter and - * queues an autoresume request if the result is > 0. The differences - * are that it does not acquire the device's pm_mutex (callers must - * handle all synchronization issues themselves), and it does not - * autoresume the device directly (it only queues a request). After a - * successful call, the device will generally not yet be resumed. + * usb_autopm_get_interface(): It increments @intf's usage counter and + * queues an autoresume request if the device is suspended. The + * differences are that it does not perform any synchronization (callers + * should hold a private lock and handle all synchronization issues + * themselves), and it does not autoresume the device directly (it only + * queues a request). After a successful call, the device may not yet be + * resumed. * * This routine can run in atomic context. */ int usb_autopm_get_interface_async(struct usb_interface *intf) { - struct usb_device *udev = interface_to_usbdev(intf); - int status = 0; + int status = 0; + enum rpm_status s; - if (intf->condition == USB_INTERFACE_UNBOUND) - status = -ENODEV; - else { + /* Don't request a resume unless the interface is already suspending + * or suspended. Doing so would force a running suspend timer to be + * cancelled. + */ + pm_runtime_get_noresume(&intf->dev); + s = ACCESS_ONCE(intf->dev.power.runtime_status); + if (s == RPM_SUSPENDING || s == RPM_SUSPENDED) + status = pm_request_resume(&intf->dev); + + if (status < 0 && status != -EINPROGRESS) + pm_runtime_put_noidle(&intf->dev); + else atomic_inc(&intf->pm_usage_cnt); - if (atomic_read(&intf->pm_usage_cnt) > 0 && - udev->state == USB_STATE_SUSPENDED) - queue_work(ksuspend_usb_wq, &udev->autoresume); - } - dev_vdbg(&intf->dev, "%s: status %d cnt %d\n", - __func__, status, atomic_read(&intf->pm_usage_cnt)); + dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n", + __func__, atomic_read(&intf->dev.power.usage_count), + status); + if (status > 0) + status = 0; return status; } EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async); -#else - -void usb_autosuspend_work(struct work_struct *work) -{} - -void usb_autoresume_work(struct work_struct *work) -{} - -#endif /* CONFIG_USB_SUSPEND */ - /** - * usb_external_suspend_device - external suspend of a USB device and its interfaces - * @udev: the usb_device to suspend - * @msg: Power Management message describing this state transition + * usb_autopm_get_interface_no_resume - increment a USB interface's PM-usage counter + * @intf: the usb_interface whose counter should be incremented * - * This routine handles external suspend requests: ones not generated - * internally by a USB driver (autosuspend) but rather coming from the user - * (via sysfs) or the PM core (system sleep). The suspend will be carried - * out regardless of @udev's usage counter or those of its interfaces, - * and regardless of whether or not remote wakeup is enabled. Of course, - * interface drivers still have the option of failing the suspend (if - * there are unsuspended children, for example). + * This routine increments @intf's usage counter but does not carry out an + * autoresume. * - * The caller must hold @udev's device lock. + * This routine can run in atomic context. */ -int usb_external_suspend_device(struct usb_device *udev, pm_message_t msg) +void usb_autopm_get_interface_no_resume(struct usb_interface *intf) { - int status; + struct usb_device *udev = interface_to_usbdev(intf); - do_unbind_rebind(udev, DO_UNBIND); - usb_pm_lock(udev); - status = usb_suspend_both(udev, msg); - usb_pm_unlock(udev); - return status; + udev->last_busy = jiffies; + atomic_inc(&intf->pm_usage_cnt); + pm_runtime_get_noresume(&intf->dev); } +EXPORT_SYMBOL_GPL(usb_autopm_get_interface_no_resume); -/** - * usb_external_resume_device - external resume of a USB device and its interfaces - * @udev: the usb_device to resume - * @msg: Power Management message describing this state transition - * - * This routine handles external resume requests: ones not generated - * internally by a USB driver (autoresume) but rather coming from the user - * (via sysfs), the PM core (system resume), or the device itself (remote - * wakeup). @udev's usage counter is unaffected. - * - * The caller must hold @udev's device lock. - */ -int usb_external_resume_device(struct usb_device *udev, pm_message_t msg) +/* Internal routine to check whether we may autosuspend a device. */ +static int autosuspend_check(struct usb_device *udev) { - int status; + int i; + struct usb_interface *intf; + unsigned long suspend_time, j; - usb_pm_lock(udev); - status = usb_resume_both(udev, msg); - udev->last_busy = jiffies; - usb_pm_unlock(udev); - if (status == 0) - do_unbind_rebind(udev, DO_REBIND); + /* Fail if autosuspend is disabled, or any interfaces are in use, or + * any interface drivers require remote wakeup but it isn't available. + */ + udev->do_remote_wakeup = device_may_wakeup(&udev->dev); + if (udev->actconfig) { + for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { + intf = udev->actconfig->interface[i]; - /* Now that the device is awake, we can start trying to autosuspend - * it again. */ - if (status == 0) - usb_try_autosuspend_device(udev); - return status; + /* We don't need to check interfaces that are + * disabled for runtime PM. Either they are unbound + * or else their drivers don't support autosuspend + * and so they are permanently active. + */ + if (intf->dev.power.disable_depth) + continue; + if (atomic_read(&intf->dev.power.usage_count) > 0) + return -EBUSY; + if (intf->needs_remote_wakeup && + !udev->do_remote_wakeup) { + dev_dbg(&udev->dev, "remote wakeup needed " + "for autosuspend\n"); + return -EOPNOTSUPP; + } + + /* Don't allow autosuspend if the device will need + * a reset-resume and any of its interface drivers + * doesn't include support or needs remote wakeup. + */ + if (udev->quirks & USB_QUIRK_RESET_RESUME) { + struct usb_driver *driver; + + driver = to_usb_driver(intf->dev.driver); + if (!driver->reset_resume || + intf->needs_remote_wakeup) + return -EOPNOTSUPP; + } + } + } + + /* If everything is okay but the device hasn't been idle for long + * enough, queue a delayed autosuspend request. + */ + j = ACCESS_ONCE(jiffies); + suspend_time = udev->last_busy + udev->autosuspend_delay; + if (time_before(j, suspend_time)) { + pm_schedule_suspend(&udev->dev, jiffies_to_msecs( + round_jiffies_up_relative(suspend_time - j))); + return -EAGAIN; + } + return 0; } -int usb_suspend(struct device *dev, pm_message_t msg) +static int usb_runtime_suspend(struct device *dev) { - struct usb_device *udev; - - udev = to_usb_device(dev); + int status = 0; - /* If udev is already suspended, we can skip this suspend and - * we should also skip the upcoming system resume. High-speed - * root hubs are an exception; they need to resume whenever the - * system wakes up in order for USB-PERSIST port handover to work - * properly. + /* A USB device can be suspended if it passes the various autosuspend + * checks. Runtime suspend for a USB device means suspending all the + * interfaces and then the device itself. */ - if (udev->state == USB_STATE_SUSPENDED) { - if (udev->parent || udev->speed != USB_SPEED_HIGH) - udev->skip_sys_resume = 1; - return 0; + if (is_usb_device(dev)) { + struct usb_device *udev = to_usb_device(dev); + + if (autosuspend_check(udev) != 0) + return -EAGAIN; + + status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND); + + /* If an interface fails the suspend, adjust the last_busy + * time so that we don't get another suspend attempt right + * away. + */ + if (status) { + udev->last_busy = jiffies + + (udev->autosuspend_delay == 0 ? + HZ/2 : 0); + } + + /* Prevent the parent from suspending immediately after */ + else if (udev->parent) { + udev->parent->last_busy = jiffies; + } } - udev->skip_sys_resume = 0; - return usb_external_suspend_device(udev, msg); + /* Runtime suspend for a USB interface doesn't mean anything. */ + return status; } -int usb_resume(struct device *dev, pm_message_t msg) +static int usb_runtime_resume(struct device *dev) { - struct usb_device *udev; - int status; + /* Runtime resume for a USB device means resuming both the device + * and all its interfaces. + */ + if (is_usb_device(dev)) { + struct usb_device *udev = to_usb_device(dev); + int status; - udev = to_usb_device(dev); + status = usb_resume_both(udev, PMSG_AUTO_RESUME); + udev->last_busy = jiffies; + return status; + } - /* If udev->skip_sys_resume is set then udev was already suspended - * when the system sleep started, so we don't want to resume it - * during this system wakeup. - */ - if (udev->skip_sys_resume) - return 0; - status = usb_external_resume_device(udev, msg); + /* Runtime resume for a USB interface doesn't mean anything. */ + return 0; +} - /* Avoid PM error messages for devices disconnected while suspended - * as we'll display regular disconnect messages just a bit later. +static int usb_runtime_idle(struct device *dev) +{ + /* An idle USB device can be suspended if it passes the various + * autosuspend checks. An idle interface can be suspended at + * any time. */ - if (status == -ENODEV) - return 0; - return status; + if (is_usb_device(dev)) { + struct usb_device *udev = to_usb_device(dev); + + if (autosuspend_check(udev) != 0) + return 0; + } + + pm_runtime_suspend(dev); + return 0; } -#endif /* CONFIG_PM */ +static struct dev_pm_ops usb_bus_pm_ops = { + .runtime_suspend = usb_runtime_suspend, + .runtime_resume = usb_runtime_resume, + .runtime_idle = usb_runtime_idle, +}; + +#else + +#define usb_bus_pm_ops (*(struct dev_pm_ops *) NULL) + +#endif /* CONFIG_USB_SUSPEND */ struct bus_type usb_bus_type = { .name = "usb", .match = usb_device_match, .uevent = usb_uevent, + .pm = &usb_bus_pm_ops, }; |