Commit 0edb5860 authored by Cornelia Huck's avatar Cornelia Huck Committed by Greg Kroah-Hartman

[PATCH] driver core: add bus_find_device & driver_find_device functions

Add bus_find_device() and driver_find_device() which allow searching for a
device in the bus's resp. the driver's klist and obtain a reference on it.
Signed-off-by: default avatarCornelia Huck <cohuck@de.ibm.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent fd782a4a
......@@ -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);
......
......@@ -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.
......
......@@ -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 *));
/*
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment