diff --git a/drivers/base/base.h b/drivers/base/base.h index 645f62692920..783752b68a9a 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -5,6 +5,7 @@ extern int bus_add_driver(struct device_driver *); extern void bus_remove_driver(struct device_driver *); extern void driver_detach(struct device_driver * drv); +extern int driver_probe_device(struct device_driver *, struct device *); static inline struct class_device *to_class_dev(struct kobject *obj) { diff --git a/drivers/base/bus.c b/drivers/base/bus.c index c3fac7fd555e..96fe2f956754 100644 --- a/drivers/base/bus.c +++ b/drivers/base/bus.c @@ -133,6 +133,58 @@ static struct kobj_type ktype_bus = { decl_subsys(bus, &ktype_bus, NULL); +/* Manually detach a device from it's associated driver. */ +static int driver_helper(struct device *dev, void *data) +{ + const char *name = data; + + if (strcmp(name, dev->bus_id) == 0) + return 1; + return 0; +} + +static ssize_t driver_unbind(struct device_driver *drv, + const char *buf, size_t count) +{ + struct bus_type *bus = get_bus(drv->bus); + struct device *dev; + int err = -ENODEV; + + dev = bus_find_device(bus, NULL, (void *)buf, driver_helper); + if ((dev) && + (dev->driver == drv)) { + device_release_driver(dev); + err = count; + } + return err; +} +static DRIVER_ATTR(unbind, S_IWUSR, NULL, driver_unbind); + +/* + * Manually attach a device to a driver. + * Note: the driver must want to bind to the device, + * it is not possible to override the driver's id table. + */ +static ssize_t driver_bind(struct device_driver *drv, + const char *buf, size_t count) +{ + struct bus_type *bus = get_bus(drv->bus); + struct device *dev; + int err = -ENODEV; + + dev = bus_find_device(bus, NULL, (void *)buf, driver_helper); + if ((dev) && + (dev->driver == NULL)) { + down(&dev->sem); + err = driver_probe_device(drv, dev); + up(&dev->sem); + put_device(dev); + } + return err; +} +static DRIVER_ATTR(bind, S_IWUSR, NULL, driver_bind); + + static struct device * next_device(struct klist_iter * i) { struct klist_node * n = klist_next(i); @@ -177,6 +229,39 @@ int bus_for_each_dev(struct bus_type * bus, struct device * start, return error; } +/** + * bus_find_device - device iterator for locating a particular device. + * @bus: bus type + * @start: Device to begin with + * @data: Data to pass to match function + * @match: Callback function to check device + * + * This is similar to the bus_for_each_dev() function above, but it + * returns a reference to a device that is 'found' for later use, as + * determined by the @match callback. + * + * The callback should return 0 if the device doesn't match and non-zero + * if it does. If the callback returns non-zero, this function will + * return to the caller and not iterate over any more devices. + */ +struct device * bus_find_device(struct bus_type *bus, + struct device *start, void *data, + int (*match)(struct device *, void *)) +{ + struct klist_iter i; + struct device *dev; + + if (!bus) + return NULL; + + klist_iter_init_node(&bus->klist_devices, &i, + (start ? &start->knode_bus : NULL)); + while ((dev = next_device(&i))) + if (match(dev, data) && get_device(dev)) + break; + klist_iter_exit(&i); + return dev; +} static struct device_driver * next_driver(struct klist_iter * i) @@ -363,6 +448,8 @@ int bus_add_driver(struct device_driver * drv) module_add_driver(drv->owner, drv); driver_add_attrs(bus, drv); + driver_create_file(drv, &driver_attr_unbind); + driver_create_file(drv, &driver_attr_bind); } return error; } @@ -380,6 +467,8 @@ int bus_add_driver(struct device_driver * drv) void bus_remove_driver(struct device_driver * drv) { if (drv->bus) { + driver_remove_file(drv, &driver_attr_bind); + driver_remove_file(drv, &driver_attr_unbind); driver_remove_attrs(drv->bus, drv); klist_remove(&drv->knode_bus); pr_debug("bus %s: remove driver %s\n", drv->bus->name, drv->name); @@ -394,31 +483,22 @@ void bus_remove_driver(struct device_driver * drv) /* Helper for bus_rescan_devices's iter */ static int bus_rescan_devices_helper(struct device *dev, void *data) { - int *count = data; - - if (!dev->driver && (device_attach(dev) > 0)) - (*count)++; - + if (!dev->driver) + device_attach(dev); return 0; } - /** - * bus_rescan_devices - rescan devices on the bus for possible drivers - * @bus: the bus to scan. + * bus_rescan_devices - rescan devices on the bus for possible drivers + * @bus: the bus to scan. * - * This function will look for devices on the bus with no driver - * attached and rescan it against existing drivers to see if it - * matches any. Calls device_attach(). Returns the number of devices - * that were sucessfully bound to a driver. + * This function will look for devices on the bus with no driver + * attached and rescan it against existing drivers to see if it matches + * any by calling device_attach() for the unbound devices. */ -int bus_rescan_devices(struct bus_type * bus) +void bus_rescan_devices(struct bus_type * bus) { - int count = 0; - - bus_for_each_dev(bus, NULL, &count, bus_rescan_devices_helper); - - return count; + bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper); } @@ -557,6 +637,7 @@ int __init buses_init(void) EXPORT_SYMBOL_GPL(bus_for_each_dev); +EXPORT_SYMBOL_GPL(bus_find_device); EXPORT_SYMBOL_GPL(bus_for_each_drv); EXPORT_SYMBOL_GPL(bus_add_device); diff --git a/drivers/base/core.c b/drivers/base/core.c index 86d79755fbfb..efe03a024a5b 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -333,7 +333,7 @@ void device_del(struct device * dev) struct device * parent = dev->parent; if (parent) - klist_remove(&dev->knode_parent); + klist_del(&dev->knode_parent); /* Notify the platform of the removal, in case they * need to do anything... diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 6db3a789c54f..16323f9cbff0 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -65,7 +65,7 @@ void device_bind_driver(struct device * dev) * * This function must be called with @dev->sem held. */ -static int driver_probe_device(struct device_driver * drv, struct device * dev) +int driver_probe_device(struct device_driver * drv, struct device * dev) { int ret = 0; diff --git a/drivers/base/driver.c b/drivers/base/driver.c index 1b645886e9eb..291c5954a3af 100644 --- a/drivers/base/driver.c +++ b/drivers/base/driver.c @@ -55,6 +55,41 @@ int driver_for_each_device(struct device_driver * drv, struct device * start, EXPORT_SYMBOL_GPL(driver_for_each_device); +/** + * driver_find_device - device iterator for locating a particular device. + * @driver: The device's driver + * @start: Device to begin with + * @data: Data to pass to match function + * @match: Callback function to check device + * + * This is similar to the driver_for_each_device() function above, but + * it returns a reference to a device that is 'found' for later use, as + * determined by the @match callback. + * + * The callback should return 0 if the device doesn't match and non-zero + * if it does. If the callback returns non-zero, this function will + * return to the caller and not iterate over any more devices. + */ +struct device * driver_find_device(struct device_driver *drv, + struct device * start, void * data, + int (*match)(struct device *, void *)) +{ + struct klist_iter i; + struct device *dev; + + if (!drv) + return NULL; + + klist_iter_init_node(&drv->klist_devices, &i, + (start ? &start->knode_driver : NULL)); + while ((dev = next_device(&i))) + if (match(dev, data) && get_device(dev)) + break; + klist_iter_exit(&i); + return dev; +} +EXPORT_SYMBOL_GPL(driver_find_device); + /** * driver_create_file - create sysfs file for driver. * @drv: driver. diff --git a/include/linux/device.h b/include/linux/device.h index 7b781a72b293..f378c846e6d5 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -69,7 +69,7 @@ struct bus_type { extern int bus_register(struct bus_type * bus); extern void bus_unregister(struct bus_type * bus); -extern int bus_rescan_devices(struct bus_type * bus); +extern void bus_rescan_devices(struct bus_type * bus); extern struct bus_type * get_bus(struct bus_type * bus); extern void put_bus(struct bus_type * bus); @@ -80,6 +80,8 @@ extern struct bus_type * find_bus(char * name); int bus_for_each_dev(struct bus_type * bus, struct device * start, void * data, int (*fn)(struct device *, void *)); +struct device * bus_find_device(struct bus_type *bus, struct device *start, + void *data, int (*match)(struct device *, void *)); int bus_for_each_drv(struct bus_type * bus, struct device_driver * start, void * data, int (*fn)(struct device_driver *, void *)); @@ -142,6 +144,9 @@ extern void driver_remove_file(struct device_driver *, struct driver_attribute * extern int driver_for_each_device(struct device_driver * drv, struct device * start, void * data, int (*fn)(struct device *, void *)); +struct device * driver_find_device(struct device_driver *drv, + struct device *start, void *data, + int (*match)(struct device *, void *)); /*