diff options
Diffstat (limited to 'drivers/base/bus.c')
| -rw-r--r-- | drivers/base/bus.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/drivers/base/bus.c b/drivers/base/bus.c index c3fac7fd555..2c64b792d07 100644 --- a/drivers/base/bus.c +++ b/drivers/base/bus.c @@ -177,6 +177,39 @@ 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) @@ -557,6 +590,7 @@ 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); |