/**
* usb_reset_configuration - lightweight device reset
* @dev: the device whose configuration is being reset
*
* This issues a standard SET_CONFIGURATION request to the device using
* the current configuration. The effect is to reset most USB-related
* state in the device, including interface altsettings (reset to zero),
* endpoint halts (cleared), and data toggle (only for bulk and interrupt
* endpoints). Other usbcore state is unchanged, including bindings of
* usb device drivers to interfaces.
*
* Because this affects multiple interfaces, avoid using this with composite
* (multi-interface) devices. Instead, the driver for each interface may
* use usb_set_interface() on the interfaces it claims. Be careful though;
* some devices don't support the SET_INTERFACE request, and others won't
* reset all the interface state (notably data toggles). Resetting the whole
* configuration would affect other drivers' interfaces.
*
* The caller must own the device lock.
*
* Returns zero on success, else a negative error code.
*/
int usb_reset_configuration(struct usb_device *dev)
{
int i, retval;
struct usb_host_config *config;
if (dev->state == USB_STATE_SUSPENDED)
return -EHOSTUNREACH;
/* caller must have locked the device and must own
* the usb bus readlock (so driver bindings are stable);
* calls during probe() are fine
*/
for (i = 1; i < 16; ++i) {
usb_disable_endpoint(dev, i);
usb_disable_endpoint(dev, i + USB_DIR_IN);
}
config = dev->actconfig;
retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
USB_REQ_SET_CONFIGURATION, 0,
config->desc.bConfigurationValue, 0,
NULL, 0, USB_CTRL_SET_TIMEOUT);
if (retval < 0)
return retval;
dev->toggle[0] = dev->toggle[1] = 0;
/* re-init hc/hcd interface/endpoint state */
for (i = 0; i < config->desc.bNumInterfaces; i++) {
struct usb_interface *intf = config->interface[i];
struct usb_host_interface *alt;
if (device_is_registered(&intf->dev))
usb_remove_sysfs_intf_files(intf);
alt = usb_altnum_to_altsetting(intf, 0);
/* No altsetting 0? We'll assume the first altsetting.
* We could use a GetInterface call, but if a device is
* so non-compliant that it doesn't have altsetting 0
* then I wouldn't trust its reply anyway.
*/
if (!alt)
alt = &intf->altsetting[0];
intf->cur_altsetting = alt;
usb_enable_interface(dev, intf);
if (device_is_registered(&intf->dev))
usb_create_sysfs_intf_files(intf);
}
return 0;
}
/**
* css_sch_device_unregister - unregister a subchannel
* @sch: subchannel to be unregistered
*/
void css_sch_device_unregister(struct subchannel *sch)
{
mutex_lock(&sch->reg_mutex);
if (device_is_registered(&sch->dev))
device_unregister(&sch->dev);
mutex_unlock(&sch->reg_mutex);
}
/**
* ccwgroup_remove_ccwdev() - remove function for slave devices
* @cdev: ccw device to be removed
*
* This is a remove function for ccw devices that are slave devices in a ccw
* group device. It sets the ccw device offline and also deregisters the
* embedding ccw group device.
*/
void ccwgroup_remove_ccwdev(struct ccw_device *cdev)
{
struct ccwgroup_device *gdev;
/* Ignore offlining errors, device is gone anyway. */
ccw_device_set_offline(cdev);
/* If one of its devices is gone, the whole group is done for. */
spin_lock_irq(cdev->ccwlock);
gdev = dev_get_drvdata(&cdev->dev);
if (!gdev) {
spin_unlock_irq(cdev->ccwlock);
return;
}
/* Get ccwgroup device reference for local processing. */
get_device(&gdev->dev);
spin_unlock_irq(cdev->ccwlock);
/* Unregister group device. */
mutex_lock(&gdev->reg_mutex);
if (device_is_registered(&gdev->dev)) {
__ccwgroup_remove_symlinks(gdev);
device_unregister(&gdev->dev);
__ccwgroup_remove_cdev_refs(gdev);
}
mutex_unlock(&gdev->reg_mutex);
/* Release ccwgroup device reference for local processing. */
put_device(&gdev->dev);
}
/*
* Provide an 'ungroup' attribute so the user can remove group devices no
* longer needed or accidentially created. Saves memory :)
*/
static void ccwgroup_ungroup(struct ccwgroup_device *gdev)
{
mutex_lock(&gdev->reg_mutex);
if (device_is_registered(&gdev->dev)) {
__ccwgroup_remove_symlinks(gdev);
device_unregister(&gdev->dev);
__ccwgroup_remove_cdev_refs(gdev);
}
mutex_unlock(&gdev->reg_mutex);
}
/*
* Provide an 'ungroup' attribute so the user can remove group devices no
* longer needed or accidentially created. Saves memory :)
*/
static void ccwgroup_ungroup_callback(struct device *dev)
{
struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
mutex_lock(&gdev->reg_mutex);
if (device_is_registered(&gdev->dev)) {
__ccwgroup_remove_symlinks(gdev);
device_unregister(dev);
}
mutex_unlock(&gdev->reg_mutex);
}
void hci_conn_del_sysfs(struct hci_conn *conn)
{
BT_DBG("conn %p", conn);
if (!device_is_registered(&conn->dev))
return;
INIT_WORK(&conn->work, del_conn);
schedule_work(&conn->work);
}
/* 该函数试图尝试将设备dev和驱动drv绑定在一起 */
int driver_probe_device(struct device_driver *drv, struct device *dev)
{
int ret = 0;
if (!device_is_registered(dev)) /* 如果设备没有没有注册则返回错误码-ENODEV*/
return -ENODEV;
pr_debug("bus: '%s': %s: matched device %s with driver %s\n",
drv->bus->name, __func__, dev_name(dev), drv->name);
ret = really_probe(dev, drv); /* */
return ret;
}
static inline struct ccwgroup_device *
__ccwgroup_get_gdev_by_cdev(struct ccw_device *cdev)
{
struct ccwgroup_device *gdev;
if (cdev->dev.driver_data) {
gdev = (struct ccwgroup_device *)cdev->dev.driver_data;
if (get_device(&gdev->dev)) {
if (device_is_registered(&gdev->dev))
return gdev;
put_device(&gdev->dev);
}
return NULL;
}
return NULL;
}
/**
* driver_probe_device - attempt to bind device & driver together
* @drv: driver to bind a device to
* @dev: device to try to bind to the driver
*
* This function returns -ENODEV if the device is not registered,
* 1 if the device is bound successfully and 0 otherwise.
*
* This function must be called with @dev lock held. When called for a
* USB interface, @dev->parent lock must be held as well.
*/
int driver_probe_device(struct device_driver *drv, struct device *dev)
{
int ret = 0;
if (!device_is_registered(dev))
return -ENODEV;
pr_debug("bus: '%s': %s: matched device %s with driver %s\n",
drv->bus->name, __func__, dev_name(dev), drv->name);
pm_runtime_get_noresume(dev);
pm_runtime_barrier(dev);
ret = really_probe(dev, drv);
pm_runtime_put_sync(dev);
return ret;
}
/**
* driver_probe_device - attempt to bind device & driver together
* @drv: driver to bind a device to
* @dev: device to try to bind to the driver
*
* First, we call the bus's match function, if one present, which should
* compare the device IDs the driver supports with the device IDs of the
* device. Note we don't do this ourselves because we don't know the
* format of the ID structures, nor what is to be considered a match and
* what is not.
*
* This function returns 1 if a match is found, -ENODEV if the device is
* not registered, and 0 otherwise.
*
* This function must be called with @dev->sem held. When called for a
* USB interface, @dev->parent->sem must be held as well.
*/
int driver_probe_device(struct device_driver *drv, struct device *dev)
{
int ret = 0;
if (!device_is_registered(dev))
return -ENODEV;
if (drv->bus->match && !drv->bus->match(dev, drv))
goto done;
pr_debug("bus: '%s': %s: matched device %s with driver %s\n",
drv->bus->name, __func__, dev_name(dev), drv->name);
ret = really_probe(dev, drv);
done:
return ret;
}
/**
* driver_probe_device - attempt to bind device & driver together
* @drv: driver to bind a device to
* @dev: device to try to bind to the driver
*
* First, we call the bus's match function, if one present, which should
* compare the device IDs the driver supports with the device IDs of the
* device. Note we don't do this ourselves because we don't know the
* format of the ID structures, nor what is to be considered a match and
* what is not.
*
* This function returns 1 if a match is found, -ENODEV if the device is
* not registered, and 0 otherwise.
*
* This function must be called with @dev->sem held. When called for a
* USB interface, @dev->parent->sem must be held as well.
*/
int driver_probe_device(struct device_driver * drv, struct device * dev)
{
int ret = 0;
if (!device_is_registered(dev))
return -ENODEV;
if (drv->bus->match && !drv->bus->match(dev, drv))
goto done;
pr_debug("%s: Matched Device %s with Driver %s\n",
drv->bus->name, dev->bus_id, drv->name);
ret = really_probe(dev, drv);
done:
return ret;
}
static struct ccwgroup_device *
__ccwgroup_get_gdev_by_cdev(struct ccw_device *cdev)
{
struct ccwgroup_device *gdev;
gdev = dev_get_drvdata(&cdev->dev);
if (gdev) {
if (get_device(&gdev->dev)) {
mutex_lock(&gdev->reg_mutex);
if (device_is_registered(&gdev->dev))
return gdev;
mutex_unlock(&gdev->reg_mutex);
put_device(&gdev->dev);
}
return NULL;
}
return NULL;
}
static void drm_minor_unregister(struct drm_device *dev, unsigned int type)
{
struct drm_minor *minor;
unsigned long flags;
minor = *drm_minor_get_slot(dev, type);
if (!minor || !device_is_registered(minor->kdev))
return;
/* replace @minor with NULL so lookups will fail from now on */
spin_lock_irqsave(&drm_minor_lock, flags);
idr_replace(&drm_minors_idr, NULL, minor->index);
spin_unlock_irqrestore(&drm_minor_lock, flags);
device_del(minor->kdev);
dev_set_drvdata(minor->kdev, NULL); /* safety belt */
drm_debugfs_cleanup(minor);
}
static struct ccwgroup_device *
__ccwgroup_get_gdev_by_cdev(struct ccw_device *cdev)
{
struct ccwgroup_device *gdev;
if (cdev->dev.driver_data) {
gdev = (struct ccwgroup_device *)cdev->dev.driver_data;
if (get_device(&gdev->dev)) {
mutex_lock(&gdev->reg_mutex);
if (device_is_registered(&gdev->dev))
return gdev;
mutex_unlock(&gdev->reg_mutex);
put_device(&gdev->dev);
}
return NULL;
}
return NULL;
}
/*
* usb_disable_device - Disable all the endpoints for a USB device
* @dev: the device whose endpoints are being disabled
* @skip_ep0: 0 to disable endpoint 0, 1 to skip it.
*
* Disables all the device's endpoints, potentially including endpoint 0.
* Deallocates hcd/hardware state for the endpoints (nuking all or most
* pending urbs) and usbcore state for the interfaces, so that usbcore
* must usb_set_configuration() before any interfaces could be used.
*/
void usb_disable_device(struct usb_device *dev, int skip_ep0)
{
int i;
dev_dbg(&dev->dev, "%s nuking %s URBs\n", __FUNCTION__,
skip_ep0 ? "non-ep0" : "all");
for (i = skip_ep0; i < 16; ++i) {
usb_disable_endpoint(dev, i);
usb_disable_endpoint(dev, i + USB_DIR_IN);
}
dev->toggle[0] = dev->toggle[1] = 0;
/* getting rid of interfaces will disconnect
* any drivers bound to them (a key side effect)
*/
if (dev->actconfig) {
for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) {
struct usb_interface *interface;
/* remove this interface if it has been registered */
interface = dev->actconfig->interface[i];
if (!device_is_registered(&interface->dev))
continue;
dev_dbg (&dev->dev, "unregistering interface %s\n",
interface->dev.bus_id);
usb_remove_sysfs_intf_files(interface);
kfree(interface->cur_altsetting->string);
interface->cur_altsetting->string = NULL;
device_del (&interface->dev);
}
/* Now that the interfaces are unbound, nobody should
* try to access them.
*/
for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) {
put_device (&dev->actconfig->interface[i]->dev);
dev->actconfig->interface[i] = NULL;
}
dev->actconfig = NULL;
if (dev->state == USB_STATE_CONFIGURED)
usb_set_device_state(dev, USB_STATE_ADDRESS);
}
}
/**
* 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 and the driver model's usb_bus_type.subsys
* writelock. So driver probe() entries don't need extra locking,
* but other call contexts may need to explicitly claim those locks.
*/
int usb_driver_claim_interface(struct usb_driver *driver,
struct usb_interface *iface, void* priv)
{
struct device *dev = &iface->dev;
if (dev->driver)
return -EBUSY;
dev->driver = &driver->driver;
usb_set_intfdata(iface, priv);
iface->condition = USB_INTERFACE_BOUND;
mark_active(iface);
/* if interface was already added, bind now; else let
* the future device_add() bind it, bypassing probe()
*/
if (device_is_registered(dev))
device_bind_driver(dev);
return 0;
}
static int gige_map_irq_callback(struct ssb_bus *bus, unsigned long data)
{
const struct pci_dev *pdev = (const struct pci_dev *)data;
struct ssb_device *dev;
unsigned int i;
int res;
for (i = 0; i < bus->nr_devices; i++) {
dev = &(bus->devices[i]);
if (dev->id.coreid != SSB_DEV_ETHERNET_GBIT)
continue;
if (!dev->dev ||
!dev->dev->driver ||
!device_is_registered(dev->dev))
continue;
res = ssb_gige_map_irq(dev, pdev);
if (res >= 0)
return res;
}
return -ENODEV;
}
/**
* 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 and the driver model's usb_bus_type.subsys
* writelock. So driver disconnect() entries don't need extra locking,
* but other call contexts may need to explicitly claim those locks.
*/
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->driver)
return;
/* don't release from within disconnect() */
if (iface->condition != USB_INTERFACE_BOUND)
return;
/* don't release if the interface hasn't been added yet */
if (device_is_registered(dev)) {
iface->condition = USB_INTERFACE_UNBINDING;
device_release_driver(dev);
}
dev->driver = NULL;
usb_set_intfdata(iface, NULL);
iface->condition = USB_INTERFACE_UNBOUND;
mark_quiesced(iface);
}
/**
* usb_set_interface - Makes a particular alternate setting be current
* @dev: the device whose interface is being updated
* @interface: the interface being updated
* @alternate: the setting being chosen.
* Context: !in_interrupt ()
*
* This is used to enable data transfers on interfaces that may not
* be enabled by default. Not all devices support such configurability.
* Only the driver bound to an interface may change its setting.
*
* Within any given configuration, each interface may have several
* alternative settings. These are often used to control levels of
* bandwidth consumption. For example, the default setting for a high
* speed interrupt endpoint may not send more than 64 bytes per microframe,
* while interrupt transfers of up to 3KBytes per microframe are legal.
* Also, isochronous endpoints may never be part of an
* interface's default setting. To access such bandwidth, alternate
* interface settings must be made current.
*
* Note that in the Linux USB subsystem, bandwidth associated with
* an endpoint in a given alternate setting is not reserved until an URB
* is submitted that needs that bandwidth. Some other operating systems
* allocate bandwidth early, when a configuration is chosen.
*
* This call is synchronous, and may not be used in an interrupt context.
* Also, drivers must not change altsettings while urbs are scheduled for
* endpoints in that interface; all such urbs must first be completed
* (perhaps forced by unlinking).
*
* Returns zero on success, or else the status code returned by the
* underlying usb_control_msg() call.
*/
int usb_set_interface(struct usb_device *dev, int interface, int alternate)
{
struct usb_interface *iface;
struct usb_host_interface *alt;
int ret;
int manual = 0;
if (dev->state == USB_STATE_SUSPENDED)
return -EHOSTUNREACH;
iface = usb_ifnum_to_if(dev, interface);
if (!iface) {
dev_dbg(&dev->dev, "selecting invalid interface %d\n",
interface);
return -EINVAL;
}
alt = usb_altnum_to_altsetting(iface, alternate);
if (!alt) {
warn("selecting invalid altsetting %d", alternate);
return -EINVAL;
}
ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
USB_REQ_SET_INTERFACE, USB_RECIP_INTERFACE,
alternate, interface, NULL, 0, 5000);
/* 9.4.10 says devices don't need this and are free to STALL the
* request if the interface only has one alternate setting.
*/
if (ret == -EPIPE && iface->num_altsetting == 1) {
dev_dbg(&dev->dev,
"manual set_interface for iface %d, alt %d\n",
interface, alternate);
manual = 1;
} else if (ret < 0)
return ret;
/* FIXME drivers shouldn't need to replicate/bugfix the logic here
* when they implement async or easily-killable versions of this or
* other "should-be-internal" functions (like clear_halt).
* should hcd+usbcore postprocess control requests?
*/
/* prevent submissions using previous endpoint settings */
if (device_is_registered(&iface->dev))
usb_remove_sysfs_intf_files(iface);
usb_disable_interface(dev, iface);
iface->cur_altsetting = alt;
/* If the interface only has one altsetting and the device didn't
* accept the request, we attempt to carry out the equivalent action
* by manually clearing the HALT feature for each endpoint in the
* new altsetting.
*/
if (manual) {
int i;
for (i = 0; i < alt->desc.bNumEndpoints; i++) {
unsigned int epaddr =
alt->endpoint[i].desc.bEndpointAddress;
unsigned int pipe =
__create_pipe(dev, USB_ENDPOINT_NUMBER_MASK & epaddr)
| (usb_endpoint_out(epaddr) ? USB_DIR_OUT : USB_DIR_IN);
usb_clear_halt(dev, pipe);
}
}
/* 9.1.1.5: reset toggles for all endpoints in the new altsetting
*
* Note:
* Despite EP0 is always present in all interfaces/AS, the list of
* endpoints from the descriptor does not contain EP0. Due to its
* omnipresence one might expect EP0 being considered "affected" by
* any SetInterface request and hence assume toggles need to be reset.
* However, EP0 toggles are re-synced for every individual transfer
* during the SETUP stage - hence EP0 toggles are "don't care" here.
* (Likewise, EP0 never "halts" on well designed devices.)
*/
usb_enable_interface(dev, iface);
if (device_is_registered(&iface->dev))
usb_create_sysfs_intf_files(iface);
return 0;
}
