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-rw-r--r--drivers/base/driver.c277
1 files changed, 277 insertions, 0 deletions
diff --git a/drivers/base/driver.c b/drivers/base/driver.c
new file mode 100644
index 0000000..1e2bda7
--- /dev/null
+++ b/drivers/base/driver.c
@@ -0,0 +1,277 @@
+/*
+ * driver.c - centralized device driver management
+ *
+ * Copyright (c) 2002-3 Patrick Mochel
+ * Copyright (c) 2002-3 Open Source Development Labs
+ * Copyright (c) 2007 Greg Kroah-Hartman <gregkh@suse.de>
+ * Copyright (c) 2007 Novell Inc.
+ *
+ * This file is released under the GPLv2
+ *
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include "base.h"
+
+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->p->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 *dev, void *data))
+{
+ struct klist_iter i;
+ struct device *dev;
+
+ if (!drv)
+ return NULL;
+
+ klist_iter_init_node(&drv->p->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.
+ * @attr: driver attribute descriptor.
+ */
+int driver_create_file(struct device_driver *drv,
+ struct driver_attribute *attr)
+{
+ int error;
+ if (drv)
+ error = sysfs_create_file(&drv->p->kobj, &attr->attr);
+ else
+ error = -EINVAL;
+ return error;
+}
+EXPORT_SYMBOL_GPL(driver_create_file);
+
+/**
+ * driver_remove_file - remove sysfs file for driver.
+ * @drv: driver.
+ * @attr: driver attribute descriptor.
+ */
+void driver_remove_file(struct device_driver *drv,
+ struct driver_attribute *attr)
+{
+ if (drv)
+ sysfs_remove_file(&drv->p->kobj, &attr->attr);
+}
+EXPORT_SYMBOL_GPL(driver_remove_file);
+
+/**
+ * driver_add_kobj - add a kobject below the specified driver
+ * @drv: requesting device driver
+ * @kobj: kobject to add below this driver
+ * @fmt: format string that names the kobject
+ *
+ * You really don't want to do this, this is only here due to one looney
+ * iseries driver, go poke those developers if you are annoyed about
+ * this...
+ */
+int driver_add_kobj(struct device_driver *drv, struct kobject *kobj,
+ const char *fmt, ...)
+{
+ va_list args;
+ char *name;
+ int ret;
+
+ va_start(args, fmt);
+ name = kvasprintf(GFP_KERNEL, fmt, args);
+ va_end(args);
+
+ if (!name)
+ return -ENOMEM;
+
+ ret = kobject_add(kobj, &drv->p->kobj, "%s", name);
+ kfree(name);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(driver_add_kobj);
+
+/**
+ * get_driver - increment driver reference count.
+ * @drv: driver.
+ */
+struct device_driver *get_driver(struct device_driver *drv)
+{
+ if (drv) {
+ struct driver_private *priv;
+ struct kobject *kobj;
+
+ kobj = kobject_get(&drv->p->kobj);
+ priv = to_driver(kobj);
+ return priv->driver;
+ }
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(get_driver);
+
+/**
+ * put_driver - decrement driver's refcount.
+ * @drv: driver.
+ */
+void put_driver(struct device_driver *drv)
+{
+ kobject_put(&drv->p->kobj);
+}
+EXPORT_SYMBOL_GPL(put_driver);
+
+static int driver_add_groups(struct device_driver *drv,
+ struct attribute_group **groups)
+{
+ int error = 0;
+ int i;
+
+ if (groups) {
+ for (i = 0; groups[i]; i++) {
+ error = sysfs_create_group(&drv->p->kobj, groups[i]);
+ if (error) {
+ while (--i >= 0)
+ sysfs_remove_group(&drv->p->kobj,
+ groups[i]);
+ break;
+ }
+ }
+ }
+ return error;
+}
+
+static void driver_remove_groups(struct device_driver *drv,
+ struct attribute_group **groups)
+{
+ int i;
+
+ if (groups)
+ for (i = 0; groups[i]; i++)
+ sysfs_remove_group(&drv->p->kobj, groups[i]);
+}
+
+/**
+ * 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
+ * structures.
+ */
+int driver_register(struct device_driver *drv)
+{
+ int ret;
+ struct device_driver *other;
+
+ 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);
+
+ other = driver_find(drv->name, drv->bus);
+ if (other) {
+ put_driver(other);
+ printk(KERN_ERR "Error: Driver '%s' is already registered, "
+ "aborting...\n", drv->name);
+ return -EEXIST;
+ }
+
+ ret = bus_add_driver(drv);
+ if (ret)
+ return ret;
+ ret = driver_add_groups(drv, drv->groups);
+ if (ret)
+ bus_remove_driver(drv);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(driver_register);
+
+/**
+ * driver_unregister - remove driver from system.
+ * @drv: driver.
+ *
+ * Again, we pass off most of the work to the bus-level call.
+ */
+void driver_unregister(struct device_driver *drv)
+{
+ driver_remove_groups(drv, drv->groups);
+ bus_remove_driver(drv);
+}
+EXPORT_SYMBOL_GPL(driver_unregister);
+
+/**
+ * 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->p->drivers_kset, name);
+ struct driver_private *priv;
+
+ if (k) {
+ priv = to_driver(k);
+ return priv->driver;
+ }
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(driver_find);
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