Commit 1f9ffc04 authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
Browse files

Driver core: add bus_find_device_by_name function 



The driver core, and some other parts of the kernel just want to find a
device based on a name for a specific bus.  Give them a simple wrapper
to prevent them from having to always roll their own.

This will be used in the PPC patch later in this series.

Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 123ca957

drivers/base/bus.c

+29 −12
Original line number Diff line number Diff line
@@ -163,15 +163,6 @@ static struct kset *bus_kset; 


#ifdef CONFIG_HOTPLUG

/* Manually detach a device from its 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)

{
@@ -179,7 +170,7 @@ static ssize_t driver_unbind(struct device_driver *drv, 
	struct device *dev;

	int err = -ENODEV;



	dev = bus_find_device(bus, NULL, (void *)buf, driver_helper);

	dev = bus_find_device_by_name(bus, NULL, buf);

	if (dev && dev->driver == drv) {

		if (dev->parent)	/* Needed for USB */

			down(&dev->parent->sem);
@@ -206,7 +197,7 @@ static ssize_t driver_bind(struct device_driver *drv, 
	struct device *dev;

	int err = -ENODEV;



	dev = bus_find_device(bus, NULL, (void *)buf, driver_helper);

	dev = bus_find_device_by_name(bus, NULL, buf);

	if (dev && dev->driver == NULL) {

		if (dev->parent)	/* Needed for USB */

			down(&dev->parent->sem);
@@ -250,7 +241,7 @@ static ssize_t store_drivers_probe(struct bus_type *bus, 
{

	struct device *dev;



	dev = bus_find_device(bus, NULL, (void *)buf, driver_helper);

	dev = bus_find_device_by_name(bus, NULL, buf);

	if (!dev)

		return -ENODEV;

	if (bus_rescan_devices_helper(dev, NULL) != 0)
@@ -338,6 +329,32 @@ struct device *bus_find_device(struct bus_type *bus, 
}

EXPORT_SYMBOL_GPL(bus_find_device);



static int match_name(struct device *dev, void *data)

{

	const char *name = data;



	if (strcmp(name, dev->bus_id) == 0)

		return 1;

	return 0;

}



/**

 * bus_find_device_by_name - device iterator for locating a particular device of a specific name

 * @bus: bus type

 * @start: Device to begin with

 * @name: name of the device to match

 *

 * This is similar to the bus_find_device() function above, but it handles

 * searching by a name automatically, no need to write another strcmp matching

 * function.

 */

struct device *bus_find_device_by_name(struct bus_type *bus,

				       struct device *start, const char *name)

{

	return bus_find_device(bus, start, (void *)name, match_name);

}

EXPORT_SYMBOL_GPL(bus_find_device_by_name);



static struct device_driver *next_driver(struct klist_iter *i)

{

	struct klist_node *n = klist_next(i);

include/linux/device.h

+3 −0
Original line number Diff line number Diff line
@@ -84,6 +84,9 @@ int bus_for_each_dev(struct bus_type *bus, struct device *start, void *data, 
struct device *bus_find_device(struct bus_type *bus, struct device *start,

			       void *data,

			       int (*match)(struct device *dev, void *data));

struct device *bus_find_device_by_name(struct bus_type *bus,

				       struct device *start,

				       const char *name);



int __must_check bus_for_each_drv(struct bus_type *bus,

				  struct device_driver *start, void *data,

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