diff options
Diffstat (limited to 'drivers/usb/core/driver.c')
| -rw-r--r-- | drivers/usb/core/driver.c | 1754 |
1 files changed, 1583 insertions, 171 deletions
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index c196f384530..4aeb10034de 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -17,72 +17,40 @@ * * NOTE! This is not actually a driver at all, rather this is * just a collection of helper routines that implement the - * generic USB things that the real drivers can use.. + * matching, probing, releasing, suspending and resuming for + * real drivers. * */ -#include <linux/config.h> #include <linux/device.h> +#include <linux/slab.h> +#include <linux/export.h> #include <linux/usb.h> -#include "hcd.h" -#include "usb.h" - -static int usb_match_one_id(struct usb_interface *interface, - const struct usb_device_id *id); - -struct usb_dynid { - struct list_head node; - struct usb_device_id id; -}; - - -static int generic_probe(struct device *dev) -{ - return 0; -} -static int generic_remove(struct device *dev) -{ - struct usb_device *udev = to_usb_device(dev); - - /* if this is only an unbind, not a physical disconnect, then - * unconfigure the device */ - if (udev->state == USB_STATE_CONFIGURED) - usb_set_configuration(udev, 0); - - /* in case the call failed or the device was suspended */ - if (udev->state >= USB_STATE_CONFIGURED) - usb_disable_device(udev, 0); - return 0; -} - -struct device_driver usb_generic_driver = { - .owner = THIS_MODULE, - .name = "usb", - .bus = &usb_bus_type, - .probe = generic_probe, - .remove = generic_remove, -}; +#include <linux/usb/quirks.h> +#include <linux/usb/hcd.h> -/* Fun hack to determine if the struct device is a - * usb device or a usb interface. */ -int usb_generic_driver_data; +#include "usb.h" -#ifdef CONFIG_HOTPLUG /* * Adds a new dynamic USBdevice ID to this driver, * and cause the driver to probe for all devices again. */ -static ssize_t store_new_id(struct device_driver *driver, - const char *buf, size_t count) +ssize_t usb_store_new_id(struct usb_dynids *dynids, + const struct usb_device_id *id_table, + struct device_driver *driver, + const char *buf, size_t count) { - struct usb_driver *usb_drv = to_usb_driver(driver); struct usb_dynid *dynid; u32 idVendor = 0; u32 idProduct = 0; + unsigned int bInterfaceClass = 0; + u32 refVendor, refProduct; int fields = 0; + int retval = 0; - fields = sscanf(buf, "%x %x", &idVendor, &idProduct); + fields = sscanf(buf, "%x %x %x %x %x", &idVendor, &idProduct, + &bInterfaceClass, &refVendor, &refProduct); if (fields < 2) return -EINVAL; @@ -94,42 +62,154 @@ static ssize_t store_new_id(struct device_driver *driver, dynid->id.idVendor = idVendor; dynid->id.idProduct = idProduct; dynid->id.match_flags = USB_DEVICE_ID_MATCH_DEVICE; + if (fields > 2 && bInterfaceClass) { + if (bInterfaceClass > 255) { + retval = -EINVAL; + goto fail; + } - spin_lock(&usb_drv->dynids.lock); - list_add_tail(&usb_drv->dynids.list, &dynid->node); - spin_unlock(&usb_drv->dynids.lock); + dynid->id.bInterfaceClass = (u8)bInterfaceClass; + dynid->id.match_flags |= USB_DEVICE_ID_MATCH_INT_CLASS; + } + + if (fields > 4) { + const struct usb_device_id *id = id_table; + + if (!id) { + retval = -ENODEV; + goto fail; + } - if (get_driver(driver)) { - driver_attach(driver); - put_driver(driver); + for (; id->match_flags; id++) + if (id->idVendor == refVendor && id->idProduct == refProduct) + break; + + if (id->match_flags) { + dynid->id.driver_info = id->driver_info; + } else { + retval = -ENODEV; + goto fail; + } } + spin_lock(&dynids->lock); + list_add_tail(&dynid->node, &dynids->list); + spin_unlock(&dynids->lock); + + retval = driver_attach(driver); + + if (retval) + return retval; + return count; + +fail: + kfree(dynid); + return retval; +} +EXPORT_SYMBOL_GPL(usb_store_new_id); + +ssize_t usb_show_dynids(struct usb_dynids *dynids, char *buf) +{ + struct usb_dynid *dynid; + size_t count = 0; + + list_for_each_entry(dynid, &dynids->list, node) + if (dynid->id.bInterfaceClass != 0) + count += scnprintf(&buf[count], PAGE_SIZE - count, "%04x %04x %02x\n", + dynid->id.idVendor, dynid->id.idProduct, + dynid->id.bInterfaceClass); + else + count += scnprintf(&buf[count], PAGE_SIZE - count, "%04x %04x\n", + dynid->id.idVendor, dynid->id.idProduct); + return count; +} +EXPORT_SYMBOL_GPL(usb_show_dynids); + +static ssize_t new_id_show(struct device_driver *driver, char *buf) +{ + struct usb_driver *usb_drv = to_usb_driver(driver); + + return usb_show_dynids(&usb_drv->dynids, buf); +} + +static ssize_t new_id_store(struct device_driver *driver, + const char *buf, size_t count) +{ + struct usb_driver *usb_drv = to_usb_driver(driver); + + return usb_store_new_id(&usb_drv->dynids, usb_drv->id_table, driver, buf, count); +} +static DRIVER_ATTR_RW(new_id); + +/* + * Remove a USB device ID from this driver + */ +static ssize_t remove_id_store(struct device_driver *driver, const char *buf, + size_t count) +{ + struct usb_dynid *dynid, *n; + struct usb_driver *usb_driver = to_usb_driver(driver); + u32 idVendor; + u32 idProduct; + int fields; + + fields = sscanf(buf, "%x %x", &idVendor, &idProduct); + if (fields < 2) + return -EINVAL; + + spin_lock(&usb_driver->dynids.lock); + list_for_each_entry_safe(dynid, n, &usb_driver->dynids.list, node) { + struct usb_device_id *id = &dynid->id; + if ((id->idVendor == idVendor) && + (id->idProduct == idProduct)) { + list_del(&dynid->node); + kfree(dynid); + break; + } + } + spin_unlock(&usb_driver->dynids.lock); return count; } -static DRIVER_ATTR(new_id, S_IWUSR, NULL, store_new_id); -static int usb_create_newid_file(struct usb_driver *usb_drv) +static ssize_t remove_id_show(struct device_driver *driver, char *buf) +{ + return new_id_show(driver, buf); +} +static DRIVER_ATTR_RW(remove_id); + +static int usb_create_newid_files(struct usb_driver *usb_drv) { int error = 0; if (usb_drv->no_dynamic_id) goto exit; - if (usb_drv->probe != NULL) - error = sysfs_create_file(&usb_drv->driver.kobj, - &driver_attr_new_id.attr); + if (usb_drv->probe != NULL) { + error = driver_create_file(&usb_drv->drvwrap.driver, + &driver_attr_new_id); + if (error == 0) { + error = driver_create_file(&usb_drv->drvwrap.driver, + &driver_attr_remove_id); + if (error) + driver_remove_file(&usb_drv->drvwrap.driver, + &driver_attr_new_id); + } + } exit: return error; } -static void usb_remove_newid_file(struct usb_driver *usb_drv) +static void usb_remove_newid_files(struct usb_driver *usb_drv) { if (usb_drv->no_dynamic_id) return; - if (usb_drv->probe != NULL) - sysfs_remove_file(&usb_drv->driver.kobj, - &driver_attr_new_id.attr); + if (usb_drv->probe != NULL) { + driver_remove_file(&usb_drv->drvwrap.driver, + &driver_attr_remove_id); + driver_remove_file(&usb_drv->drvwrap.driver, + &driver_attr_new_id); + } } static void usb_free_dynids(struct usb_driver *usb_drv) @@ -143,20 +223,6 @@ static void usb_free_dynids(struct usb_driver *usb_drv) } spin_unlock(&usb_drv->dynids.lock); } -#else -static inline int usb_create_newid_file(struct usb_driver *usb_drv) -{ - return 0; -} - -static void usb_remove_newid_file(struct usb_driver *usb_drv) -{ -} - -static inline void usb_free_dynids(struct usb_driver *usb_drv) -{ -} -#endif static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *intf, struct usb_driver *drv) @@ -175,84 +241,375 @@ static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *in } -/* called from driver core with usb_bus_type.subsys writelock */ +/* called from driver core with dev locked */ +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 = 0; + + dev_dbg(dev, "%s\n", __func__); + + /* TODO: Add real matching code */ + + /* The device should always appear to be in use + * unless the driver supports autosuspend. + */ + if (!udriver->supports_autosuspend) + error = usb_autoresume_device(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(udev); + if (!udriver->supports_autosuspend) + usb_autosuspend_device(udev); + return 0; +} + +/* + * Cancel any pending scheduled resets + * + * [see usb_queue_reset_device()] + * + * Called after unconfiguring / when releasing interfaces. See + * comments in __usb_queue_reset_device() regarding + * udev->reset_running. + */ +static void usb_cancel_queued_reset(struct usb_interface *iface) +{ + if (iface->reset_running == 0) + cancel_work_sync(&iface->reset_ws); +} + +/* called from driver core with dev locked */ static int usb_probe_interface(struct device *dev) { - struct usb_interface * intf = to_usb_interface(dev); - struct usb_driver * driver = to_usb_driver(dev->driver); + struct usb_driver *driver = to_usb_driver(dev->driver); + struct usb_interface *intf = to_usb_interface(dev); + struct usb_device *udev = interface_to_usbdev(intf); const struct usb_device_id *id; int error = -ENODEV; + int lpm_disable_error; + + dev_dbg(dev, "%s\n", __func__); - dev_dbg(dev, "%s\n", __FUNCTION__); + intf->needs_binding = 0; - if (!driver->probe) + if (usb_device_is_owned(udev)) return error; - /* FIXME we'd much prefer to just resume it ... */ - if (interface_to_usbdev(intf)->state == USB_STATE_SUSPENDED) - return -EHOSTUNREACH; - id = usb_match_id(intf, driver->id_table); + if (udev->authorized == 0) { + dev_err(&intf->dev, "Device is not authorized for usage\n"); + return error; + } + + id = usb_match_dynamic_id(intf, driver); + if (!id) + 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", __FUNCTION__); + 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; - error = driver->probe(intf, id); - if (error) { - mark_quiesced(intf); - intf->condition = USB_INTERFACE_UNBOUND; - } else - intf->condition = USB_INTERFACE_BOUND; + dev_dbg(dev, "%s - got id\n", __func__); + + error = usb_autoresume_device(udev); + if (error) + return error; + + intf->condition = USB_INTERFACE_BINDING; + + /* Probed 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 the new driver doesn't allow hub-initiated LPM, and we can't + * disable hub-initiated LPM, then fail the probe. + * + * Otherwise, leaving LPM enabled should be harmless, because the + * endpoint intervals should remain the same, and the U1/U2 timeouts + * should remain the same. + * + * If we need to install alt setting 0 before probe, or another alt + * setting during probe, that should also be fine. usb_set_interface() + * will attempt to disable LPM, and fail if it can't disable it. + */ + lpm_disable_error = usb_unlocked_disable_lpm(udev); + if (lpm_disable_error && driver->disable_hub_initiated_lpm) { + dev_err(&intf->dev, "%s Failed to disable LPM for driver %s\n.", + __func__, driver->name); + error = lpm_disable_error; + goto err; + } + + /* 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->needs_altsetting0 = 0; } + error = driver->probe(intf, id); + if (error) + goto err; + + intf->condition = USB_INTERFACE_BOUND; + + /* If the LPM disable succeeded, balance the ref counts. */ + if (!lpm_disable_error) + usb_unlocked_enable_lpm(udev); + + usb_autosuspend_device(udev); + return error; + + err: + usb_set_intfdata(intf, NULL); + intf->needs_remote_wakeup = 0; + intf->condition = USB_INTERFACE_UNBOUND; + usb_cancel_queued_reset(intf); + + /* If the LPM disable succeeded, balance the ref counts. */ + if (!lpm_disable_error) + usb_unlocked_enable_lpm(udev); + + /* Unbound interfaces are always runtime-PM-disabled and -suspended */ + if (driver->supports_autosuspend) + pm_runtime_disable(dev); + pm_runtime_set_suspended(dev); + + usb_autosuspend_device(udev); return error; } -/* called from driver core with usb_bus_type.subsys writelock */ +/* called from driver core with dev locked */ static int usb_unbind_interface(struct device *dev) { + struct usb_driver *driver = to_usb_driver(dev->driver); struct usb_interface *intf = to_usb_interface(dev); - struct usb_driver *driver = to_usb_driver(intf->dev.driver); + struct usb_host_endpoint *ep, **eps = NULL; + struct usb_device *udev; + int i, j, error, r, lpm_disable_error; intf->condition = USB_INTERFACE_UNBINDING; - /* release all urbs for this interface */ - usb_disable_interface(interface_to_usbdev(intf), intf); - - if (driver && driver->disconnect) - driver->disconnect(intf); + /* Autoresume for set_interface call below */ + udev = interface_to_usbdev(intf); + error = usb_autoresume_device(udev); + + /* Hub-initiated LPM policy may change, so attempt to disable LPM until + * the driver is unbound. If LPM isn't disabled, that's fine because it + * wouldn't be enabled unless all the bound interfaces supported + * hub-initiated LPM. + */ + lpm_disable_error = usb_unlocked_disable_lpm(udev); + + /* Terminate all URBs for this interface unless the driver + * supports "soft" unbinding. + */ + if (!driver->soft_unbind) + usb_disable_interface(udev, intf, false); + + driver->disconnect(intf); + usb_cancel_queued_reset(intf); + + /* Free streams */ + for (i = 0, j = 0; i < intf->cur_altsetting->desc.bNumEndpoints; i++) { + ep = &intf->cur_altsetting->endpoint[i]; + if (ep->streams == 0) + continue; + if (j == 0) { + eps = kmalloc(USB_MAXENDPOINTS * sizeof(void *), + GFP_KERNEL); + if (!eps) { + dev_warn(dev, "oom, leaking streams\n"); + break; + } + } + eps[j++] = ep; + } + if (j) { + usb_free_streams(intf, eps, j, GFP_KERNEL); + kfree(eps); + } - /* reset other interface state */ - usb_set_interface(interface_to_usbdev(intf), - intf->altsetting[0].desc.bInterfaceNumber, - 0); + /* Reset other interface state. + * We cannot do a Set-Interface if the device is suspended or + * if it is prepared for a system sleep (since installing a new + * altsetting means creating new endpoint device entries). + * When either of these happens, defer the Set-Interface. + */ + if (intf->cur_altsetting->desc.bAlternateSetting == 0) { + /* Already in altsetting 0 so skip Set-Interface. + * Just re-enable it without affecting the endpoint toggles. + */ + usb_enable_interface(udev, intf, false); + } else if (!error && !intf->dev.power.is_prepared) { + r = usb_set_interface(udev, intf->altsetting[0]. + desc.bInterfaceNumber, 0); + if (r < 0) + intf->needs_altsetting0 = 1; + } else { + intf->needs_altsetting0 = 1; + } usb_set_intfdata(intf, NULL); + intf->condition = USB_INTERFACE_UNBOUND; - mark_quiesced(intf); + intf->needs_remote_wakeup = 0; + + /* Attempt to re-enable USB3 LPM, if the disable succeeded. */ + if (!lpm_disable_error) + usb_unlocked_enable_lpm(udev); + + /* Unbound interfaces are always runtime-PM-disabled and -suspended */ + if (driver->supports_autosuspend) + 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); return 0; } -/* returns 0 if no match, 1 if match */ -static int usb_match_one_id(struct usb_interface *interface, - const struct usb_device_id *id) +/** + * usb_driver_claim_interface - bind a driver to an interface + * @driver: the driver to be bound + * @iface: the interface to which it will be bound; must be in the + * usb device's active configuration + * @priv: driver data associated with that interface + * + * This is used by usb device drivers that need to claim more than one + * interface on a device when probing (audio and acm are current examples). + * No device driver should directly modify internal usb_interface or + * usb_device structure members. + * + * Few drivers should need to use this routine, since the most natural + * way to bind to an interface is to return the private data from + * the driver's probe() method. + * + * Callers must own the device lock, so driver probe() entries don't need + * extra locking, but other call contexts may need to explicitly claim that + * lock. + * + * Return: 0 on success. + */ +int usb_driver_claim_interface(struct usb_driver *driver, + struct usb_interface *iface, void *priv) { - struct usb_host_interface *intf; - struct usb_device *dev; + struct device *dev = &iface->dev; + struct usb_device *udev; + int retval = 0; + int lpm_disable_error; - /* proc_connectinfo in devio.c may call us with id == NULL. */ - if (id == NULL) - return 0; + if (dev->driver) + return -EBUSY; - intf = interface->cur_altsetting; - dev = interface_to_usbdev(interface); + udev = interface_to_usbdev(iface); + + dev->driver = &driver->drvwrap.driver; + usb_set_intfdata(iface, priv); + iface->needs_binding = 0; + + iface->condition = USB_INTERFACE_BOUND; + + /* Disable LPM until this driver is bound. */ + lpm_disable_error = usb_unlocked_disable_lpm(udev); + if (lpm_disable_error && driver->disable_hub_initiated_lpm) { + dev_err(&iface->dev, "%s Failed to disable LPM for driver %s\n.", + __func__, driver->name); + return -ENOMEM; + } + + /* Claimed interfaces are initially inactive (suspended) and + * runtime-PM-enabled, but only if the driver has autosuspend + * support. Otherwise they are marked active, to prevent the + * device from being autosuspended, but left disabled. In either + * case they are sensitive to their children's power states. + */ + pm_suspend_ignore_children(dev, false); + if (driver->supports_autosuspend) + pm_runtime_enable(dev); + else + pm_runtime_set_active(dev); + + /* if interface was already added, bind now; else let + * the future device_add() bind it, bypassing probe() + */ + if (device_is_registered(dev)) + retval = device_bind_driver(dev); + + /* Attempt to re-enable USB3 LPM, if the disable was successful. */ + if (!lpm_disable_error) + usb_unlocked_enable_lpm(udev); + + return retval; +} +EXPORT_SYMBOL_GPL(usb_driver_claim_interface); + +/** + * usb_driver_release_interface - unbind a driver from an interface + * @driver: the driver to be unbound + * @iface: the interface from which it will be unbound + * + * This can be used by drivers to release an interface without waiting + * for their disconnect() methods to be called. In typical cases this + * also causes the driver disconnect() method to be called. + * + * This call is synchronous, and may not be used in an interrupt context. + * Callers must own the device lock, so driver disconnect() entries don't + * need extra locking, but other call contexts may need to explicitly claim + * that lock. + */ +void usb_driver_release_interface(struct usb_driver *driver, + struct usb_interface *iface) +{ + struct device *dev = &iface->dev; + + /* this should never happen, don't release something that's not ours */ + if (!dev->driver || dev->driver != &driver->drvwrap.driver) + return; + + /* don't release from within disconnect() */ + if (iface->condition != USB_INTERFACE_BOUND) + return; + iface->condition = USB_INTERFACE_UNBINDING; + + /* Release via the driver core only if the interface + * has already been registered + */ + if (device_is_registered(dev)) { + device_release_driver(dev); + } else { + device_lock(dev); + usb_unbind_interface(dev); + dev->driver = NULL; + device_unlock(dev); + } +} +EXPORT_SYMBOL_GPL(usb_driver_release_interface); +/* returns 0 if no match, 1 if match */ +int usb_match_device(struct usb_device *dev, const struct usb_device_id *id) +{ if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) && id->idVendor != le16_to_cpu(dev->descriptor.idVendor)) return 0; @@ -276,13 +633,32 @@ static int usb_match_one_id(struct usb_interface *interface, return 0; if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) && - (id->bDeviceSubClass!= dev->descriptor.bDeviceSubClass)) + (id->bDeviceSubClass != dev->descriptor.bDeviceSubClass)) return 0; if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) && (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol)) return 0; + return 1; +} + +/* returns 0 if no match, 1 if match */ +int usb_match_one_id_intf(struct usb_device *dev, + struct usb_host_interface *intf, + const struct usb_device_id *id) +{ + /* The interface class, subclass, protocol and number should never be + * checked for a match if the device class is Vendor Specific, + * unless the match record specifies the Vendor ID. */ + if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC && + !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) && + (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS | + USB_DEVICE_ID_MATCH_INT_SUBCLASS | + USB_DEVICE_ID_MATCH_INT_PROTOCOL | + USB_DEVICE_ID_MATCH_INT_NUMBER))) + return 0; + if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) && (id->bInterfaceClass != intf->desc.bInterfaceClass)) return 0; @@ -295,8 +671,34 @@ static int usb_match_one_id(struct usb_interface *interface, (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol)) return 0; + if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER) && + (id->bInterfaceNumber != intf->desc.bInterfaceNumber)) + return 0; + return 1; } + +/* returns 0 if no match, 1 if match */ +int usb_match_one_id(struct usb_interface *interface, + const struct usb_device_id *id) +{ + struct usb_host_interface *intf; + struct usb_device *dev; + + /* proc_connectinfo in devio.c may call us with id == NULL. */ + if (id == NULL) + return 0; + + intf = interface->cur_altsetting; + dev = interface_to_usbdev(interface); + + if (!usb_match_device(dev, id)) + return 0; + + return usb_match_one_id_intf(dev, intf, id); +} +EXPORT_SYMBOL_GPL(usb_match_one_id); + /** * usb_match_id - find first usb_device_id matching device or interface * @interface: the interface of interest @@ -310,6 +712,8 @@ static int usb_match_one_id(struct usb_interface *interface, * These device tables are exported with MODULE_DEVICE_TABLE, through * modutils, to support the driver loading functionality of USB hotplugging. * + * Return: The first matching usb_device_id, or %NULL. + * * What Matches: * * The "match_flags" element in a usb_device_id controls which @@ -351,7 +755,17 @@ static int usb_match_one_id(struct usb_interface *interface, * most general; they let drivers bind to any interface on a * multiple-function device. Use the USB_INTERFACE_INFO * macro, or its siblings, to match class-per-interface style - * devices (as recorded in bDeviceClass). + * devices (as recorded in bInterfaceClass). + * + * Note that an entry created by USB_INTERFACE_INFO won't match + * any interface if the device class is set to Vendor-Specific. + * This is deliberate; according to the USB spec the meanings of + * the interface class/subclass/protocol for these devices are also + * vendor-specific, and hence matching against a standard product + * class wouldn't work anyway. If you really want to use an + * interface-based match for such a device, create a match record + * that also specifies the vendor ID. (Unforunately there isn't a + * standard macro for creating records like this.) * * Within those groups, remember that not all combinations are * meaningful. For example, don't give a product version range @@ -370,87 +784,210 @@ const struct usb_device_id *usb_match_id(struct usb_interface *interface, id->driver_info is the way to create an entry that indicates that the driver want to examine every device and interface. */ - for (; id->idVendor || id->bDeviceClass || id->bInterfaceClass || - id->driver_info; id++) { + for (; id->idVendor || id->idProduct || id->bDeviceClass || + id->bInterfaceClass || id->driver_info; id++) { if (usb_match_one_id(interface, id)) return id; } return NULL; } -EXPORT_SYMBOL_GPL_FUTURE(usb_match_id); +EXPORT_SYMBOL_GPL(usb_match_id); -int usb_device_match(struct device *dev, struct device_driver *drv) +static int usb_device_match(struct device *dev, struct device_driver *drv) { - struct usb_interface *intf; - struct usb_driver *usb_drv; - const struct usb_device_id *id; + /* devices and interfaces are handled separately */ + if (is_usb_device(dev)) { + + /* interface drivers never match devices */ + if (!is_usb_device_driver(drv)) + return 0; - /* check for generic driver, which we don't match any device with */ - if (drv == &usb_generic_driver) + /* TODO: Add real matching code */ + return 1; + + } else if (is_usb_interface(dev)) { + struct usb_interface *intf; + struct usb_driver *usb_drv; + const struct usb_device_id *id; + + /* device drivers never match interfaces */ + if (is_usb_device_driver(drv)) + return 0; + + intf = to_usb_interface(dev); + usb_drv = to_usb_driver(drv); + + id = usb_match_id(intf, usb_drv->id_table); + if (id) + return 1; + + id = usb_match_dynamic_id(intf, usb_drv); + if (id) + return 1; + } + + return 0; +} + +static int usb_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct usb_device *usb_dev; + + if (is_usb_device(dev)) { + usb_dev = to_usb_device(dev); + } else if (is_usb_interface(dev)) { + struct usb_interface *intf = to_usb_interface(dev); + + usb_dev = interface_to_usbdev(intf); + } else { return 0; + } - intf = to_usb_interface(dev); - usb_drv = to_usb_driver(drv); + 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; + } + if (!usb_dev->bus) { + pr_debug("usb %s: bus removed?\n", dev_name(dev)); + return -ENODEV; + } - id = usb_match_id(intf, usb_drv->id_table); - if (id) - return 1; + /* per-device configurations are common */ + if (add_uevent_var(env, "PRODUCT=%x/%x/%x", + le16_to_cpu(usb_dev->descriptor.idVendor), + le16_to_cpu(usb_dev->descriptor.idProduct), + le16_to_cpu(usb_dev->descriptor.bcdDevice))) + return -ENOMEM; + + /* class-based driver binding models */ + if (add_uevent_var(env, "TYPE=%d/%d/%d", + usb_dev->descriptor.bDeviceClass, + usb_dev->descriptor.bDeviceSubClass, + usb_dev->descriptor.bDeviceProtocol)) + return -ENOMEM; - id = usb_match_dynamic_id(intf, usb_drv); - if (id) - return 1; return 0; } /** - * usb_register_driver - register a USB driver - * @new_driver: USB operations for the driver + * usb_register_device_driver - register a USB device (not interface) driver + * @new_udriver: USB operations for the device driver * @owner: module owner of this driver. * - * Registers a USB driver with the USB core. The list of unattached - * interfaces will be rescanned whenever a new driver is added, allowing - * the new driver to attach to any recognized devices. - * Returns a negative error code on failure and 0 on success. + * Registers a USB device driver with the USB core. The list of + * unattached devices will be rescanned whenever a new driver is + * added, allowing the new driver to attach to any recognized devices. + * + * Return: A negative error code on failure and 0 on success. + */ +int usb_register_device_driver(struct usb_device_driver *new_udriver, + struct module *owner) +{ + int retval = 0; + + if (usb_disabled()) + return -ENODEV; + + new_udriver->drvwrap.for_devices = 1; + new_udriver->drvwrap.driver.name = new_udriver->name; + new_udriver->drvwrap.driver.bus = &usb_bus_type; + new_udriver->drvwrap.driver.probe = usb_probe_device; + new_udriver->drvwrap.driver.remove = usb_unbind_device; + new_udriver->drvwrap.driver.owner = owner; + + retval = driver_register(&new_udriver->drvwrap.driver); + + if (!retval) + pr_info("%s: registered new device driver %s\n", + usbcore_name, new_udriver->name); + else + printk(KERN_ERR "%s: error %d registering device " + " driver %s\n", + usbcore_name, retval, new_udriver->name); + + return retval; +} +EXPORT_SYMBOL_GPL(usb_register_device_driver); + +/** + * usb_deregister_device_driver - unregister a USB device (not interface) driver + * @udriver: USB operations of the device driver to unregister + * Context: must be able to sleep + * + * Unlinks the specified driver from the internal USB driver list. + */ +void usb_deregister_device_driver(struct usb_device_driver *udriver) +{ + pr_info("%s: deregistering device driver %s\n", + usbcore_name, udriver->name); + + driver_unregister(&udriver->drvwrap.driver); +} +EXPORT_SYMBOL_GPL(usb_deregister_device_driver); + +/** + * usb_register_driver - register a USB interface driver + * @new_driver: USB operations for the interface driver + * @owner: module owner of this driver. + * @mod_name: module name string + * + * Registers a USB interface driver with the USB core. The list of + * unattached interfaces will be rescanned whenever a new driver is + * added, allowing the new driver to attach to any recognized interfaces. + * + * Return: A negative error code on failure and 0 on success. * * NOTE: if you want your driver to use the USB major number, you must call * usb_register_dev() to enable that functionality. This function no longer * takes care of that. */ -int usb_register_driver(struct usb_driver *new_driver, struct module *owner) +int usb_register_driver(struct usb_driver *new_driver, struct module *owner, + const char *mod_name) { int retval = 0; if (usb_disabled()) return -ENODEV; - new_driver->driver.name = (char *)new_driver->name; - new_driver->driver.bus = &usb_bus_type; - new_driver->driver.probe = usb_probe_interface; - new_driver->driver.remove = usb_unbind_interface; - new_driver->driver.owner = owner; + new_driver->drvwrap.for_devices = 0; + new_driver->drvwrap.driver.name = new_driver->name; + new_driver->drvwrap.driver.bus = &usb_bus_type; + new_driver->drvwrap.driver.probe = usb_probe_interface; + new_driver->drvwrap.driver.remove = usb_unbind_interface; + new_driver->drvwrap.driver.owner = owner; + new_driver->drvwrap.driver.mod_name = mod_name; spin_lock_init(&new_driver->dynids.lock); INIT_LIST_HEAD(&new_driver->dynids.list); - retval = driver_register(&new_driver->driver); + retval = driver_register(&new_driver->drvwrap.driver); + if (retval) + goto out; - if (!retval) { - pr_info("%s: registered new driver %s\n", + retval = usb_create_newid_files(new_driver); + if (retval) + goto out_newid; + + pr_info("%s: registered new interface driver %s\n", usbcore_name, new_driver->name); - usbfs_update_special(); - usb_create_newid_file(new_driver); - } else { - printk(KERN_ERR "%s: error %d registering driver %s\n", - usbcore_name, retval, new_driver->name); - } +out: return retval; + +out_newid: + driver_unregister(&new_driver->drvwrap.driver); + + printk(KERN_ERR "%s: error %d registering interface " + " driver %s\n", + usbcore_name, retval, new_driver->name); + goto out; } -EXPORT_SYMBOL_GPL_FUTURE(usb_register_driver); +EXPORT_SYMBOL_GPL(usb_register_driver); /** - * usb_deregister - unregister a USB driver - * @driver: USB operations of the driver to unregister + * usb_deregister - unregister a USB interface driver + * @driver: USB operations of the interface driver to unregister * Context: must be able to sleep * * Unlinks the specified driver from the internal USB driver list. @@ -461,12 +998,887 @@ EXPORT_SYMBOL_GPL_FUTURE(usb_register_driver); */ void usb_deregister(struct usb_driver *driver) { - pr_info("%s: deregistering driver %s\n", usbcore_name, driver->name); + pr_info("%s: deregistering interface driver %s\n", + usbcore_name, driver->name); - usb_remove_newid_file(driver); + usb_remove_newid_files(driver); + driver_unregister(&driver->drvwrap.driver); usb_free_dynids(driver); - driver_unregister(&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 @intf's lock. + */ +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; +} + +/* + * Unbind drivers for @udev's marked interfaces. These interfaces have + * the needs_binding flag set, for example by usb_resume_interface(). + * + * The caller must hold @udev's device lock. + */ +static void unbind_marked_interfaces(struct usb_device *udev) +{ + struct usb_host_config *config; + int i; + struct usb_interface *intf; + + config = udev->actconfig; + if (config) { + for (i = 0; i < config->desc.bNumInterfaces; ++i) { + intf = config->interface[i]; + if (intf->dev.driver && intf->needs_binding) + usb_forced_unbind_intf(intf); + } + } +} + +/* Delayed forced unbinding of a USB interface driver and scan + * for rebinding. + * + * The caller must hold @intf's device's lock, but not @intf's lock. + * + * Note: Rebinds will be skipped if a system sleep transition is in + * progress and the PM "complete" callback hasn't occurred yet. + */ +static void usb_rebind_intf(struct usb_interface *intf) +{ + int rc; + + /* Delayed unbind of an existing driver */ + if (intf->dev.driver) + usb_forced_unbind_intf(intf); + + /* Try to rebind the interface */ + if (!intf->dev.power.is_prepared) { + intf->needs_binding = 0; + rc = device_attach(&intf->dev); + if (rc < 0) + dev_warn(&intf->dev, "rebind failed: %d\n", rc); + } +} + +/* + * Rebind drivers to @udev's marked interfaces. These interfaces have + * the needs_binding flag set. + * + * The caller must hold @udev's device lock. + */ +static void rebind_marked_interfaces(struct usb_device *udev) +{ + struct usb_host_config *config; + int i; + struct usb_interface *intf; + + config = udev->actconfig; + if (config) { + for (i = 0; i < config->desc.bNumInterfaces; ++i) { + intf = config->interface[i]; + if (intf->needs_binding) + usb_rebind_intf(intf); + } + } +} + +/* + * Unbind all of @udev's marked interfaces and then rebind all of them. + * This ordering is necessary because some drivers claim several interfaces + * when they are first probed. + * + * The caller must hold @udev's device lock. + */ +void usb_unbind_and_rebind_marked_interfaces(struct usb_device *udev) +{ + unbind_marked_interfaces(udev); + rebind_marked_interfaces(udev); +} + +#ifdef CONFIG_PM + +/* Unbind drivers for @udev's interfaces that don't support suspend/resume + * There is no check for reset_resume here because it can be determined + * only during resume whether reset_resume is needed. + * + * The caller must hold @udev's device lock. + */ +static void unbind_no_pm_drivers_interfaces(struct usb_device *udev) +{ + 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]; + + if (intf->dev.driver) { + drv = to_usb_driver(intf->dev.driver); + if (!drv->suspend || !drv->resume) + usb_forced_unbind_intf(intf); + } + } + } +} + +static int usb_suspend_device(struct usb_device *udev, pm_message_t msg) +{ + struct usb_device_driver *udriver; + int status = 0; + + if (udev->state == USB_STATE_NOTATTACHED || + udev->state == USB_STATE_SUSPENDED) + goto done; + + /* For devices that don't have a driver, we do a generic suspend. */ + if (udev->dev.driver) + udriver = to_usb_device_driver(udev->dev.driver); + else { + udev->do_remote_wakeup = 0; + udriver = &usb_generic_driver; + } + status = udriver->suspend(udev, msg); + + done: + dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status); + return status; +} + +static int usb_resume_device(struct usb_device *udev, pm_message_t msg) +{ + struct usb_device_driver *udriver; + int status = 0; + + if (udev->state == USB_STATE_NOTATTACHED) + goto done; + + /* Can't resume it if it doesn't have a driver. */ + if (udev->dev.driver == NULL) { + status = -ENOTCONN; + 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 (!PMSG_IS_AUTO(msg) && 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; + + udriver = to_usb_device_driver(udev->dev.driver); + status = udriver->resume(udev, msg); + + done: + dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status); + return status; +} + +static int usb_suspend_interface(struct usb_device *udev, + struct usb_interface *intf, pm_message_t msg) +{ + struct usb_driver *driver; + int status = 0; + + if (udev->state == USB_STATE_NOTATTACHED || + intf->condition == USB_INTERFACE_UNBOUND) + goto done; + driver = to_usb_driver(intf->dev.driver); + + /* at this time we know the driver supports suspend */ + status = driver->suspend(intf, msg); + if (status && !PMSG_IS_AUTO(msg)) + dev_err(&intf->dev, "suspend error %d\n", status); + + done: + dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status); + return status; +} + +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) + goto done; + + /* Don't let autoresume interfere with unbinding */ + if (intf->condition == USB_INTERFACE_UNBINDING) + goto done; + + /* Can't resume it if it doesn't have a driver. */ + if (intf->condition == USB_INTERFACE_UNBOUND) { + + /* Carry out a deferred switch to altsetting 0 */ + if (intf->needs_altsetting0 && !intf->dev.power.is_prepared) { + usb_set_interface(udev, intf->altsetting[0]. + desc.bInterfaceNumber, 0); + intf->needs_altsetting0 = 0; + } + 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) { + if (driver->reset_resume) { + status = driver->reset_resume(intf); + if (status) + dev_err(&intf->dev, "%s error %d\n", + "reset_resume", status); + } else { + intf->needs_binding = 1; + dev_dbg(&intf->dev, "no reset_resume for driver %s?\n", + driver->name); + } + } else { + status = driver->resume(intf); + if (status) + dev_err(&intf->dev, "resume error %d\n", status); + } + +done: + dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status); + + /* Later we will unbind the driver and/or reprobe, if necessary */ + return status; +} + +/** + * usb_suspend_both - suspend a USB device and its interfaces + * @udev: the usb_device to suspend + * @msg: Power Management message describing this state transition + * + * This is the central routine for suspending USB devices. It calls the + * suspend methods for all the interface drivers in @udev and then calls + * the suspend method for @udev itself. When the routine is called in + * autosuspend, if an error occurs at any stage, all the interfaces + * which were suspended are resumed so that they remain in the same + * state as the device, but when called from system sleep, all error + * from suspend methods of interfaces and the non-root-hub device itself + * are simply ignored, so all suspended interfaces are only resumed + * to the device's state when @udev is root-hub and its suspend method + * returns failure. + * + * 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. + * + * Return: 0 if the suspend succeeded. + */ +static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) +{ + int status = 0; + int i = 0, n = 0; + struct usb_interface *intf; + + if (udev->state == USB_STATE_NOTATTACHED || + udev->state == USB_STATE_SUSPENDED) + goto done; + + /* Suspend all the interfaces and then udev itself */ + if (udev->actconfig) { + n = udev->actconfig->desc.bNumInterfaces; + for (i = n - 1; i >= 0; --i) { + intf = udev->actconfig->interface[i]; + status = usb_suspend_interface(udev, intf, msg); + + /* Ignore errors during system sleep transitions */ + if (!PMSG_IS_AUTO(msg)) + status = 0; + if (status != 0) + break; + } + } + if (status == 0) { + status = usb_suspend_device(udev, msg); + + /* + * Ignore errors from non-root-hub devices during + * system sleep transitions. For the most part, + * these devices should go to low power anyway when + * the entire bus is suspended. + */ + if (udev->parent && !PMSG_IS_AUTO(msg)) + status = 0; + } + + /* If the suspend failed, resume interfaces that did get suspended */ + if (status != 0) { + if (udev->actconfig) { + msg.event ^= (PM_EVENT_SUSPEND | PM_EVENT_RESUME); + while (++i < n) { + intf = udev->actconfig->interface[i]; + usb_resume_interface(udev, intf, msg, 0); + } + } + + /* If the suspend succeeded then prevent any more URB submissions + * and flush any outstanding URBs. + */ + } else { + 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]); + } + } + + done: + dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status); + return status; +} + +/** + * usb_resume_both - resume a USB device and its interfaces + * @udev: the usb_device to resume + * @msg: Power Management message describing this state transition + * + * This is the central routine for resuming USB devices. It calls the + * the resume method for @udev and then calls the resume methods for all + * the interface drivers in @udev. + * + * 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. + * + * Return: 0 on success. + */ +static int usb_resume_both(struct usb_device *udev, pm_message_t msg) +{ + int status = 0; + int i; + struct usb_interface *intf; + + if (udev->state == USB_STATE_NOTATTACHED) { + status = -ENODEV; + goto done; + } + udev->can_submit = 1; + + /* 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]; + usb_resume_interface(udev, intf, msg, + udev->reset_resume); + } + } + usb_mark_last_busy(udev); + + done: + dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status); + if (!status) + udev->reset_resume = 0; + return status; +} + +static void choose_wakeup(struct usb_device *udev, pm_message_t msg) +{ + int w; + + /* Remote wakeup is needed only when we actually go to sleep. + * For things like FREEZE and QUIESCE, if the device is already + * autosuspended then its current wakeup setting is okay. + */ + if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_QUIESCE) { + if (udev->state != USB_STATE_SUSPENDED) + udev->do_remote_wakeup = 0; + return; + } - usbfs_update_special(); + /* Enable remote wakeup if it is allowed, even if no interface drivers + * actually want it. + */ + w = device_may_wakeup(&udev->dev); + + /* If the device is autosuspended with the wrong wakeup setting, + * autoresume now so the setting can be changed. + */ + if (udev->state == USB_STATE_SUSPENDED && w != udev->do_remote_wakeup) + pm_runtime_resume(&udev->dev); + udev->do_remote_wakeup = w; } -EXPORT_SYMBOL_GPL_FUTURE(usb_deregister); + +/* 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); + + unbind_no_pm_drivers_interfaces(udev); + + /* From now on we are sure all drivers support suspend/resume + * but not necessarily reset_resume() + * so we may still need to unbind and rebind upon resume + */ + choose_wakeup(udev, msg); + return usb_suspend_both(udev, msg); +} + +/* The device lock is held by the PM core */ +int usb_resume_complete(struct device *dev) +{ + struct usb_device *udev = to_usb_device(dev); + + /* For PM complete calls, all we do is rebind interfaces + * whose needs_binding flag is set + */ + if (udev->state != USB_STATE_NOTATTACHED) + rebind_marked_interfaces(udev); + return 0; +} + +/* The device lock is held by the PM core */ +int usb_resume(struct device *dev, pm_message_t msg) +{ + struct usb_device *udev = to_usb_device(dev); + int status; + + /* For all calls, take the device back to full power and + * tell the PM core in case it was autosuspended previously. + * Unbind the interfaces that will need rebinding later, + * because they fail to support reset_resume. + * (This can't be done in usb_resume_interface() + * above because it doesn't own the right set of locks.) + */ + status = usb_resume_both(udev, msg); + if (status == 0) { + pm_runtime_disable(dev); + pm_runtime_set_active(dev); + pm_runtime_enable(dev); + unbind_marked_interfaces(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 == -ESHUTDOWN) + status = 0; + return status; +} + +#endif /* CONFIG_PM */ + +#ifdef CONFIG_PM_RUNTIME + +/** + * 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. + */ +void usb_enable_autosuspend(struct usb_device *udev) +{ + pm_runtime_allow(&udev->dev); +} +EXPORT_SYMBOL_GPL(usb_enable_autosuspend); + +/** + * 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. + */ +void usb_disable_autosuspend(struct usb_device *udev) +{ + pm_runtime_forbid(&udev->dev); +} +EXPORT_SYMBOL_GPL(usb_disable_autosuspend); + +/** + * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces + * @udev: the usb_device to autosuspend + * + * This routine should be called when a core subsystem is finished using + * @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 drops to 0 and all the + * interfaces are inactive then a delayed autosuspend will be attempted. + * The attempt may fail (see autosuspend_check()). + * + * The caller must hold @udev's device lock. + * + * This routine can run only in process context. + */ +void usb_autosuspend_device(struct usb_device *udev) +{ + int status; + + usb_mark_last_busy(udev); + status = pm_runtime_put_sync_autosuspend(&udev->dev); + dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n", + __func__, atomic_read(&udev->dev.power.usage_count), + status); +} + +/** + * usb_autoresume_device - immediately autoresume a USB device and its interfaces + * @udev: the usb_device to autoresume + * + * 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 + * 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. + * + * The caller must hold @udev's device lock. + * + * This routine can run only in process context. + * + * Return: 0 on success. A negative error code otherwise. + */ +int usb_autoresume_device(struct usb_device *udev) +{ + int status; + + 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; +} + +/** + * usb_autopm_put_interface - decrement a USB interface's PM-usage counter + * @intf: the usb_interface whose counter should be decremented + * + * This routine should be called by an interface driver when it is + * finished using @intf and wants to allow it to autosuspend. A typical + * example would be a character-device driver when its device file is + * closed. + * + * The routine decrements @intf's usage counter. When the counter reaches + * 0, a delayed autosuspend request for @intf's device is attempted. The + * attempt may fail (see autosuspend_check()). + * + * This routine can run only in process context. + */ +void usb_autopm_put_interface(struct usb_interface *intf) +{ + struct usb_device *udev = interface_to_usbdev(intf); + int status; + + usb_mark_last_busy(udev); + 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); + +/** + * 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 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. + * + * This routine can run in atomic context. + */ +void usb_autopm_put_interface_async(struct usb_interface *intf) +{ + struct usb_device *udev = interface_to_usbdev(intf); + int status; + + usb_mark_last_busy(udev); + atomic_dec(&intf->pm_usage_cnt); + status = pm_runtime_put(&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_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); + + usb_mark_last_busy(udev); + 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 + * + * This routine should be called by an interface driver when it wants to + * use @intf and needs to guarantee that it is not suspended. In addition, + * the routine prevents @intf from being autosuspended subsequently. (Note + * that this will not prevent suspend events originating in the PM core.) + * This prevention will persist until usb_autopm_put_interface() is called + * or @intf is unbound. A typical example would be a character-device + * driver when its device file is opened. + * + * @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. + * + * Return: 0 on success. + */ +int usb_autopm_get_interface(struct usb_interface *intf) +{ + int status; + + 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); + +/** + * usb_autopm_get_interface_async - increment a USB interface's PM-usage counter + * @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 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. + * + * Return: 0 on success. A negative error code otherwise. + */ +int usb_autopm_get_interface_async(struct usb_interface *intf) +{ + int status; + + status = pm_runtime_get(&intf->dev); + if (status < 0 && status != -EINPROGRESS) + pm_runtime_put_noidle(&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 == -EINPROGRESS) + status = 0; + return status; +} +EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async); + +/** + * 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 increments @intf's usage counter but does not carry out an + * autoresume. + * + * This routine can run in atomic context. + */ +void usb_autopm_get_interface_no_resume(struct usb_interface *intf) +{ + struct usb_device *udev = interface_to_usbdev(intf); + + usb_mark_last_busy(udev); + atomic_inc(&intf->pm_usage_cnt); + pm_runtime_get_noresume(&intf->dev); +} +EXPORT_SYMBOL_GPL(usb_autopm_get_interface_no_resume); + +/* Internal routine to check whether we may autosuspend a device. */ +static int autosuspend_check(struct usb_device *udev) +{ + int w, i; + struct usb_interface *intf; + + /* Fail if autosuspend is disabled, or any interfaces are in use, or + * any interface drivers require remote wakeup but it isn't available. + */ + w = 0; + if (udev->actconfig) { + for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { + intf = udev->actconfig->interface[i]; + + /* 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; + w |= intf->needs_remote_wakeup; + + /* 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 (w && !device_can_wakeup(&udev->dev)) { + dev_dbg(&udev->dev, "remote wakeup needed for autosuspend\n"); + return -EOPNOTSUPP; + } + udev->do_remote_wakeup = w; + return 0; +} + +int usb_runtime_suspend(struct device *dev) +{ + struct usb_device *udev = to_usb_device(dev); + int status; + + /* 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 (autosuspend_check(udev) != 0) + return -EAGAIN; + + status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND); + + /* Allow a retry if autosuspend failed temporarily */ + if (status == -EAGAIN || status == -EBUSY) + usb_mark_last_busy(udev); + + /* + * The PM core reacts badly unless the return code is 0, + * -EAGAIN, or -EBUSY, so always return -EBUSY on an error + * (except for root hubs, because they don't suspend through + * an upstream port like other USB devices). + */ + if (status != 0 && udev->parent) + return -EBUSY; + return status; +} + +int usb_runtime_resume(struct device *dev) +{ + struct usb_device *udev = to_usb_device(dev); + int status; + + /* Runtime resume for a USB device means resuming both the device + * and all its interfaces. + */ + status = usb_resume_both(udev, PMSG_AUTO_RESUME); + return status; +} + +int usb_runtime_idle(struct device *dev) +{ + struct usb_device *udev = to_usb_device(dev); + + /* An idle USB device can be suspended if it passes the various + * autosuspend checks. + */ + if (autosuspend_check(udev) == 0) + pm_runtime_autosuspend(dev); + /* Tell the core not to suspend it, though. */ + return -EBUSY; +} + +int usb_set_usb2_hardware_lpm(struct usb_device *udev, int enable) +{ + struct usb_hcd *hcd = bus_to_hcd(udev->bus); + int ret = -EPERM; + + if (enable && !udev->usb2_hw_lpm_allowed) + return 0; + + if (hcd->driver->set_usb2_hw_lpm) { + ret = hcd->driver->set_usb2_hw_lpm(hcd, udev, enable); + if (!ret) + udev->usb2_hw_lpm_enabled = enable; + } + + return ret; +} + +#endif /* CONFIG_PM_RUNTIME */ + +struct bus_type usb_bus_type = { + .name = "usb", + .match = usb_device_match, + .uevent = usb_uevent, +}; |