X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fbase%2Fdriver.c;h=1214cbd17d868bf1613bcf79ee079cabef95ca62;hb=refs%2Fheads%2Fvserver;hp=0236ba33542b9dbde06ef6e1f6f9846d510fb321;hpb=5273a3df6485dc2ad6aa7ddd441b9a21970f003b;p=linux-2.6.git diff --git a/drivers/base/driver.c b/drivers/base/driver.c index 0236ba335..1214cbd17 100644 --- a/drivers/base/driver.c +++ b/drivers/base/driver.c @@ -3,20 +3,92 @@ * * Copyright (c) 2002-3 Patrick Mochel * Copyright (c) 2002-3 Open Source Development Labs - * + * * This file is released under the GPLv2 * */ -#include #include #include #include #include #include "base.h" -#define to_dev(node) container_of(node,struct device,driver_list) -#define to_drv(obj) container_of(obj,struct device_driver,kobj) +#define to_dev(node) container_of(node, struct device, driver_list) +#define to_drv(obj) container_of(obj, struct device_driver, kobj) + + +static struct device * next_device(struct klist_iter * i) +{ + struct klist_node * n = klist_next(i); + return n ? container_of(n, struct device, knode_driver) : NULL; +} + +/** + * driver_for_each_device - Iterator for devices bound to a driver. + * @drv: Driver we're iterating. + * @start: Device to begin with + * @data: Data to pass to the callback. + * @fn: Function to call for each device. + * + * Iterate over the @drv's list of devices calling @fn for each one. + */ + +int driver_for_each_device(struct device_driver * drv, struct device * start, + void * data, int (*fn)(struct device *, void *)) +{ + struct klist_iter i; + struct device * dev; + int error = 0; + + if (!drv) + return -EINVAL; + + klist_iter_init_node(&drv->klist_devices, &i, + start ? &start->knode_driver : NULL); + while ((dev = next_device(&i)) && !error) + error = fn(dev, data); + klist_iter_exit(&i); + return error; +} + +EXPORT_SYMBOL_GPL(driver_for_each_device); + + +/** + * driver_find_device - device iterator for locating a particular device. + * @drv: 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. @@ -28,7 +100,7 @@ int driver_create_file(struct device_driver * drv, struct driver_attribute * att { int error; if (get_driver(drv)) { - error = sysfs_create_file(&drv->kobj,&attr->attr); + error = sysfs_create_file(&drv->kobj, &attr->attr); put_driver(drv); } else error = -EINVAL; @@ -45,7 +117,7 @@ int driver_create_file(struct device_driver * drv, struct driver_attribute * att void driver_remove_file(struct device_driver * drv, struct driver_attribute * attr) { if (get_driver(drv)) { - sysfs_remove_file(&drv->kobj,&attr->attr); + sysfs_remove_file(&drv->kobj, &attr->attr); put_driver(drv); } } @@ -70,23 +142,27 @@ void put_driver(struct device_driver * drv) kobject_put(&drv->kobj); } - /** * driver_register - register driver with bus * @drv: driver to register * * We pass off most of the work to the bus_add_driver() call, - * since most of the things we have to do deal with the bus + * since most of the things we have to do deal with the bus * structures. * - * The one interesting aspect is that we initialize @drv->unload_sem - * to a locked state here. It will be unlocked when the driver - * reference count reaches 0. + * The one interesting aspect is that we setup @drv->unloaded + * as a completion that gets complete when the driver reference + * count reaches 0. */ int driver_register(struct device_driver * drv) { - INIT_LIST_HEAD(&drv->devices); - init_MUTEX_LOCKED(&drv->unload_sem); + if ((drv->bus->probe && drv->probe) || + (drv->bus->remove && drv->remove) || + (drv->bus->shutdown && drv->shutdown)) { + printk(KERN_WARNING "Driver '%s' needs updating - please use bus_type methods\n", drv->name); + } + klist_init(&drv->klist_devices, NULL, NULL); + init_completion(&drv->unloaded); return bus_add_driver(drv); } @@ -97,24 +173,42 @@ int driver_register(struct device_driver * drv) * * Again, we pass off most of the work to the bus-level call. * - * Though, once that is done, we attempt to take @drv->unload_sem. + * Though, once that is done, we wait until @drv->unloaded is completed. * This will block until the driver refcount reaches 0, and it is - * released. Only modular drivers will call this function, and we - * have to guarantee that it won't complete, letting the driver + * released. Only modular drivers will call this function, and we + * have to guarantee that it won't complete, letting the driver * unload until all references are gone. */ void driver_unregister(struct device_driver * drv) { bus_remove_driver(drv); - down(&drv->unload_sem); - up(&drv->unload_sem); + wait_for_completion(&drv->unloaded); +} + +/** + * driver_find - locate driver on a bus by its name. + * @name: name of the driver. + * @bus: bus to scan for the driver. + * + * Call kset_find_obj() to iterate over list of drivers on + * a bus to find driver by name. Return driver if found. + * + * Note that kset_find_obj increments driver's reference count. + */ +struct device_driver *driver_find(const char *name, struct bus_type *bus) +{ + struct kobject *k = kset_find_obj(&bus->drivers, name); + if (k) + return to_drv(k); + return NULL; } -EXPORT_SYMBOL(driver_register); -EXPORT_SYMBOL(driver_unregister); -EXPORT_SYMBOL(get_driver); -EXPORT_SYMBOL(put_driver); +EXPORT_SYMBOL_GPL(driver_register); +EXPORT_SYMBOL_GPL(driver_unregister); +EXPORT_SYMBOL_GPL(get_driver); +EXPORT_SYMBOL_GPL(put_driver); +EXPORT_SYMBOL_GPL(driver_find); -EXPORT_SYMBOL(driver_create_file); -EXPORT_SYMBOL(driver_remove_file); +EXPORT_SYMBOL_GPL(driver_create_file); +EXPORT_SYMBOL_GPL(driver_remove_file);