diff options
| -rw-r--r-- | drivers/usb/core/driver.c | 131 | ||||
| -rw-r--r-- | drivers/usb/core/hub.c | 27 | ||||
| -rw-r--r-- | drivers/usb/core/usb.h | 2 | ||||
| -rw-r--r-- | include/linux/usb.h | 1 |
4 files changed, 140 insertions, 21 deletions
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index 8da1a56659b..ddb54e14a5c 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -201,6 +201,7 @@ static int usb_probe_interface(struct device *dev) intf = to_usb_interface(dev); udev = interface_to_usbdev(intf); + intf->needs_binding = 0; if (udev->authorized == 0) { dev_err(&intf->dev, "Device is not authorized for usage\n"); @@ -311,6 +312,7 @@ int usb_driver_claim_interface(struct usb_driver *driver, dev->driver = &driver->drvwrap.driver; usb_set_intfdata(iface, priv); + iface->needs_binding = 0; usb_pm_lock(udev); iface->condition = USB_INTERFACE_BOUND; @@ -772,6 +774,104 @@ void usb_deregister(struct usb_driver *driver) } EXPORT_SYMBOL_GPL(usb_deregister); + +/* Forced unbinding of a USB interface driver, either because + * it doesn't support pre_reset/post_reset/reset_resume or + * because it doesn't support suspend/resume. + * + * The caller must hold @intf's device's lock, but not its pm_mutex + * and not @intf->dev.sem. + */ +void usb_forced_unbind_intf(struct usb_interface *intf) +{ + struct usb_driver *driver = to_usb_driver(intf->dev.driver); + + dev_dbg(&intf->dev, "forced unbind\n"); + usb_driver_release_interface(driver, intf); + + /* Mark the interface for later rebinding */ + intf->needs_binding = 1; +} + +/* Delayed forced unbinding of a USB interface driver and scan + * for rebinding. + * + * The caller must hold @intf's device's lock, but not its pm_mutex + * and not @intf->dev.sem. + * + * FIXME: The caller must block system sleep transitions. + */ +void usb_rebind_intf(struct usb_interface *intf) +{ + int rc; + + /* Delayed unbind of an existing driver */ + if (intf->dev.driver) { + struct usb_driver *driver = + to_usb_driver(intf->dev.driver); + + dev_dbg(&intf->dev, "forced unbind\n"); + usb_driver_release_interface(driver, intf); + } + + /* Try to rebind the interface */ + intf->needs_binding = 0; + rc = device_attach(&intf->dev); + if (rc < 0) + dev_warn(&intf->dev, "rebind failed: %d\n", rc); +} + +#define DO_UNBIND 0 +#define DO_REBIND 1 + +/* Unbind drivers for @udev's interfaces that don't support suspend/resume, + * or rebind interfaces that have been unbound, according to @action. + * + * The caller must hold @udev's device lock. + * FIXME: For rebinds, the caller must block system sleep transitions. + */ +static void do_unbind_rebind(struct usb_device *udev, int action) +{ + struct usb_host_config *config; + int i; + struct usb_interface *intf; + struct usb_driver *drv; + + config = udev->actconfig; + if (config) { + for (i = 0; i < config->desc.bNumInterfaces; ++i) { + intf = config->interface[i]; + switch (action) { + case DO_UNBIND: + if (intf->dev.driver) { + drv = to_usb_driver(intf->dev.driver); + if (!drv->suspend || !drv->resume) + usb_forced_unbind_intf(intf); + } + break; + case DO_REBIND: + if (intf->needs_binding) { + + /* FIXME: The next line is needed because we are going to probe + * the interface, but as far as the PM core is concerned the + * interface is still suspended. The problem wouldn't exist + * if we could rebind the interface during the interface's own + * resume() call, but at the time the usb_device isn't locked! + * + * The real solution will be to carry this out during the device's + * complete() callback. Until that is implemented, we have to + * use this hack. + */ +// intf->dev.power.sleeping = 0; + + usb_rebind_intf(intf); + } + break; + } + } + } +} + #ifdef CONFIG_PM /* Caller has locked udev's pm_mutex */ @@ -841,7 +941,7 @@ static int usb_suspend_interface(struct usb_interface *intf, pm_message_t msg) goto done; driver = to_usb_driver(intf->dev.driver); - if (driver->suspend && driver->resume) { + if (driver->suspend) { status = driver->suspend(intf, msg); if (status == 0) mark_quiesced(intf); @@ -849,12 +949,10 @@ static int usb_suspend_interface(struct usb_interface *intf, pm_message_t msg) dev_err(&intf->dev, "%s error %d\n", "suspend", status); } else { - /* - * FIXME else if there's no suspend method, disconnect... - * Not possible if auto_pm is set... - */ - dev_warn(&intf->dev, "no suspend for driver %s?\n", - driver->name); + /* Later we will unbind the driver and reprobe */ + intf->needs_binding = 1; + dev_warn(&intf->dev, "no %s for driver %s?\n", + "suspend", driver->name); mark_quiesced(intf); } @@ -878,10 +976,12 @@ static int usb_resume_interface(struct usb_interface *intf, int reset_resume) goto done; /* Can't resume it if it doesn't have a driver. */ - if (intf->condition == USB_INTERFACE_UNBOUND) { - status = -ENOTCONN; + if (intf->condition == USB_INTERFACE_UNBOUND) + goto done; + + /* Don't resume if the interface is marked for rebinding */ + if (intf->needs_binding) goto done; - } driver = to_usb_driver(intf->dev.driver); if (reset_resume) { @@ -891,7 +991,7 @@ static int usb_resume_interface(struct usb_interface *intf, int reset_resume) dev_err(&intf->dev, "%s error %d\n", "reset_resume", status); } else { - /* status = -EOPNOTSUPP; */ + intf->needs_binding = 1; dev_warn(&intf->dev, "no %s for driver %s?\n", "reset_resume", driver->name); } @@ -902,7 +1002,7 @@ static int usb_resume_interface(struct usb_interface *intf, int reset_resume) dev_err(&intf->dev, "%s error %d\n", "resume", status); } else { - /* status = -EOPNOTSUPP; */ + intf->needs_binding = 1; dev_warn(&intf->dev, "no %s for driver %s?\n", "resume", driver->name); } @@ -910,11 +1010,10 @@ static int usb_resume_interface(struct usb_interface *intf, int reset_resume) done: dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status); - if (status == 0) + if (status == 0 && intf->condition == USB_INTERFACE_BOUND) mark_active(intf); - /* FIXME: Unbind the driver and reprobe if the resume failed - * (not possible if auto_pm is set) */ + /* Later we will unbind the driver and/or reprobe, if necessary */ return status; } @@ -1470,6 +1569,7 @@ int usb_external_suspend_device(struct usb_device *udev, pm_message_t msg) { int status; + do_unbind_rebind(udev, DO_UNBIND); usb_pm_lock(udev); udev->auto_pm = 0; status = usb_suspend_both(udev, msg); @@ -1497,6 +1597,7 @@ int usb_external_resume_device(struct usb_device *udev) status = usb_resume_both(udev); udev->last_busy = jiffies; usb_pm_unlock(udev); + do_unbind_rebind(udev, DO_REBIND); /* Now that the device is awake, we can start trying to autosuspend * it again. */ diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index bb3ecc4c08f..f1efabbc1ca 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -3367,6 +3367,11 @@ re_enumerate: * 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_device(struct usb_device *udev) { @@ -3388,12 +3393,17 @@ int usb_reset_device(struct usb_device *udev) 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); } } } @@ -3404,13 +3414,18 @@ int usb_reset_device(struct usb_device *udev) 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 (rebind) + usb_rebind_intf(cintf); } } diff --git a/drivers/usb/core/usb.h b/drivers/usb/core/usb.h index 1a8bc21c335..d3eb0a29bca 100644 --- a/drivers/usb/core/usb.h +++ b/drivers/usb/core/usb.h @@ -29,6 +29,8 @@ extern int usb_choose_configuration(struct usb_device *udev); extern void usb_kick_khubd(struct usb_device *dev); extern int usb_match_device(struct usb_device *dev, const struct usb_device_id *id); +extern void usb_forced_unbind_intf(struct usb_interface *intf); +extern void usb_rebind_intf(struct usb_interface *intf); extern int usb_hub_init(void); extern void usb_hub_cleanup(void); diff --git a/include/linux/usb.h b/include/linux/usb.h index 3cc8db5254d..5811c5da69f 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -160,6 +160,7 @@ struct usb_interface { unsigned is_active:1; /* the interface is not suspended */ unsigned sysfs_files_created:1; /* the sysfs attributes exist */ unsigned needs_remote_wakeup:1; /* driver requires remote wakeup */ + unsigned needs_binding:1; /* needs delayed unbind/rebind */ struct device dev; /* interface specific device info */ struct device *usb_dev; |