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Diffstat (limited to 'drivers/base/class.c')
-rw-r--r--drivers/base/class.c151
1 files changed, 101 insertions, 50 deletions
diff --git a/drivers/base/class.c b/drivers/base/class.c
index ce23dc8c18c5..db65fd0babe9 100644
--- a/drivers/base/class.c
+++ b/drivers/base/class.c
@@ -17,6 +17,7 @@
#include <linux/string.h>
#include <linux/kdev_t.h>
#include <linux/err.h>
+#include <linux/slab.h>
#include "base.h"
#define to_class_attr(_attr) container_of(_attr, struct class_attribute, attr)
@@ -99,7 +100,8 @@ struct class * class_get(struct class * cls)
void class_put(struct class * cls)
{
- subsys_put(&cls->subsys);
+ if (cls)
+ subsys_put(&cls->subsys);
}
@@ -165,14 +167,25 @@ void class_unregister(struct class * cls)
static void class_create_release(struct class *cls)
{
+ pr_debug("%s called for %s\n", __FUNCTION__, cls->name);
kfree(cls);
}
static void class_device_create_release(struct class_device *class_dev)
{
+ pr_debug("%s called for %s\n", __FUNCTION__, class_dev->class_id);
kfree(class_dev);
}
+/* needed to allow these devices to have parent class devices */
+static int class_device_create_hotplug(struct class_device *class_dev,
+ char **envp, int num_envp,
+ char *buffer, int buffer_size)
+{
+ pr_debug("%s called for %s\n", __FUNCTION__, class_dev->class_id);
+ return 0;
+}
+
/**
* class_create - create a struct class structure
* @owner: pointer to the module that is to "own" this struct class
@@ -301,10 +314,12 @@ static void class_dev_release(struct kobject * kobj)
kfree(cd->devt_attr);
cd->devt_attr = NULL;
- if (cls->release)
+ if (cd->release)
+ cd->release(cd);
+ else if (cls->release)
cls->release(cd);
else {
- printk(KERN_ERR "Device class '%s' does not have a release() function, "
+ printk(KERN_ERR "Class Device '%s' does not have a release() function, "
"it is broken and must be fixed.\n",
cd->class_id);
WARN_ON(1);
@@ -382,14 +397,18 @@ static int class_hotplug(struct kset *kset, struct kobject *kobj, char **envp,
buffer = &buffer[length];
buffer_size -= length;
- if (class_dev->class->hotplug) {
- /* have the bus specific function add its stuff */
- retval = class_dev->class->hotplug (class_dev, envp, num_envp,
- buffer, buffer_size);
- if (retval) {
- pr_debug ("%s - hotplug() returned %d\n",
- __FUNCTION__, retval);
- }
+ if (class_dev->hotplug) {
+ /* have the class device specific function add its stuff */
+ retval = class_dev->hotplug(class_dev, envp, num_envp,
+ buffer, buffer_size);
+ if (retval)
+ pr_debug("class_dev->hotplug() returned %d\n", retval);
+ } else if (class_dev->class->hotplug) {
+ /* have the class specific function add its stuff */
+ retval = class_dev->class->hotplug(class_dev, envp, num_envp,
+ buffer, buffer_size);
+ if (retval)
+ pr_debug("class->hotplug() returned %d\n", retval);
}
return retval;
@@ -442,6 +461,13 @@ static ssize_t show_dev(struct class_device *class_dev, char *buf)
return print_dev_t(buf, class_dev->devt);
}
+static ssize_t store_uevent(struct class_device *class_dev,
+ const char *buf, size_t count)
+{
+ kobject_hotplug(&class_dev->kobj, KOBJ_ADD);
+ return count;
+}
+
void class_device_initialize(struct class_device *class_dev)
{
kobj_set_kset_s(class_dev, class_obj_subsys);
@@ -469,34 +495,45 @@ static char *make_class_name(struct class_device *class_dev)
int class_device_add(struct class_device *class_dev)
{
- struct class * parent = NULL;
- struct class_interface * class_intf;
+ struct class *parent_class = NULL;
+ struct class_device *parent_class_dev = NULL;
+ struct class_interface *class_intf;
char *class_name = NULL;
- int error;
+ int error = -EINVAL;
class_dev = class_device_get(class_dev);
if (!class_dev)
return -EINVAL;
- if (!strlen(class_dev->class_id)) {
- error = -EINVAL;
+ if (!strlen(class_dev->class_id))
goto register_done;
- }
- parent = class_get(class_dev->class);
+ parent_class = class_get(class_dev->class);
+ if (!parent_class)
+ goto register_done;
+ parent_class_dev = class_device_get(class_dev->parent);
pr_debug("CLASS: registering class device: ID = '%s'\n",
class_dev->class_id);
/* first, register with generic layer. */
kobject_set_name(&class_dev->kobj, "%s", class_dev->class_id);
- if (parent)
- class_dev->kobj.parent = &parent->subsys.kset.kobj;
+ if (parent_class_dev)
+ class_dev->kobj.parent = &parent_class_dev->kobj;
+ else
+ class_dev->kobj.parent = &parent_class->subsys.kset.kobj;
- if ((error = kobject_add(&class_dev->kobj)))
+ error = kobject_add(&class_dev->kobj);
+ if (error)
goto register_done;
/* add the needed attributes to this device */
+ class_dev->uevent_attr.attr.name = "uevent";
+ class_dev->uevent_attr.attr.mode = S_IWUSR;
+ class_dev->uevent_attr.attr.owner = parent_class->owner;
+ class_dev->uevent_attr.store = store_uevent;
+ class_device_create_file(class_dev, &class_dev->uevent_attr);
+
if (MAJOR(class_dev->devt)) {
struct class_device_attribute *attr;
attr = kzalloc(sizeof(*attr), GFP_KERNEL);
@@ -505,12 +542,10 @@ int class_device_add(struct class_device *class_dev)
kobject_del(&class_dev->kobj);
goto register_done;
}
-
attr->attr.name = "dev";
attr->attr.mode = S_IRUGO;
- attr->attr.owner = parent->owner;
+ attr->attr.owner = parent_class->owner;
attr->show = show_dev;
- attr->store = NULL;
class_device_create_file(class_dev, attr);
class_dev->devt_attr = attr;
}
@@ -524,20 +559,23 @@ int class_device_add(struct class_device *class_dev)
class_name);
}
+ kobject_hotplug(&class_dev->kobj, KOBJ_ADD);
+
/* notify any interfaces this device is now here */
- if (parent) {
- down(&parent->sem);
- list_add_tail(&class_dev->node, &parent->children);
- list_for_each_entry(class_intf, &parent->interfaces, node)
+ if (parent_class) {
+ down(&parent_class->sem);
+ list_add_tail(&class_dev->node, &parent_class->children);
+ list_for_each_entry(class_intf, &parent_class->interfaces, node)
if (class_intf->add)
- class_intf->add(class_dev);
- up(&parent->sem);
+ class_intf->add(class_dev, class_intf);
+ up(&parent_class->sem);
}
- kobject_hotplug(&class_dev->kobj, KOBJ_ADD);
register_done:
- if (error && parent)
- class_put(parent);
+ if (error) {
+ class_put(parent_class);
+ class_device_put(parent_class_dev);
+ }
class_device_put(class_dev);
kfree(class_name);
return error;
@@ -552,21 +590,28 @@ int class_device_register(struct class_device *class_dev)
/**
* class_device_create - creates a class device and registers it with sysfs
* @cs: pointer to the struct class that this device should be registered to.
+ * @parent: pointer to the parent struct class_device of this new device, if any.
* @dev: the dev_t for the char device to be added.
* @device: a pointer to a struct device that is assiociated with this class device.
* @fmt: string for the class device's name
*
* This function can be used by char device classes. A struct
* class_device will be created in sysfs, registered to the specified
- * class. A "dev" file will be created, showing the dev_t for the
- * device. The pointer to the struct class_device will be returned from
- * the call. Any further sysfs files that might be required can be
- * created using this pointer.
+ * class.
+ * A "dev" file will be created, showing the dev_t for the device, if
+ * the dev_t is not 0,0.
+ * If a pointer to a parent struct class_device is passed in, the newly
+ * created struct class_device will be a child of that device in sysfs.
+ * The pointer to the struct class_device will be returned from the
+ * call. Any further sysfs files that might be required can be created
+ * using this pointer.
*
* Note: the struct class passed to this function must have previously
* been created with a call to class_create().
*/
-struct class_device *class_device_create(struct class *cls, dev_t devt,
+struct class_device *class_device_create(struct class *cls,
+ struct class_device *parent,
+ dev_t devt,
struct device *device, char *fmt, ...)
{
va_list args;
@@ -585,6 +630,9 @@ struct class_device *class_device_create(struct class *cls, dev_t devt,
class_dev->devt = devt;
class_dev->dev = device;
class_dev->class = cls;
+ class_dev->parent = parent;
+ class_dev->release = class_device_create_release;
+ class_dev->hotplug = class_device_create_hotplug;
va_start(args, fmt);
vsnprintf(class_dev->class_id, BUS_ID_SIZE, fmt, args);
@@ -602,17 +650,18 @@ error:
void class_device_del(struct class_device *class_dev)
{
- struct class * parent = class_dev->class;
- struct class_interface * class_intf;
+ struct class *parent_class = class_dev->class;
+ struct class_device *parent_device = class_dev->parent;
+ struct class_interface *class_intf;
char *class_name = NULL;
- if (parent) {
- down(&parent->sem);
+ if (parent_class) {
+ down(&parent_class->sem);
list_del_init(&class_dev->node);
- list_for_each_entry(class_intf, &parent->interfaces, node)
+ list_for_each_entry(class_intf, &parent_class->interfaces, node)
if (class_intf->remove)
- class_intf->remove(class_dev);
- up(&parent->sem);
+ class_intf->remove(class_dev, class_intf);
+ up(&parent_class->sem);
}
if (class_dev->dev) {
@@ -620,6 +669,7 @@ void class_device_del(struct class_device *class_dev)
sysfs_remove_link(&class_dev->kobj, "device");
sysfs_remove_link(&class_dev->dev->kobj, class_name);
}
+ class_device_remove_file(class_dev, &class_dev->uevent_attr);
if (class_dev->devt_attr)
class_device_remove_file(class_dev, class_dev->devt_attr);
class_device_remove_attrs(class_dev);
@@ -627,8 +677,8 @@ void class_device_del(struct class_device *class_dev)
kobject_hotplug(&class_dev->kobj, KOBJ_REMOVE);
kobject_del(&class_dev->kobj);
- if (parent)
- class_put(parent);
+ class_device_put(parent_device);
+ class_put(parent_class);
kfree(class_name);
}
@@ -708,7 +758,8 @@ struct class_device * class_device_get(struct class_device *class_dev)
void class_device_put(struct class_device *class_dev)
{
- kobject_put(&class_dev->kobj);
+ if (class_dev)
+ kobject_put(&class_dev->kobj);
}
@@ -728,7 +779,7 @@ int class_interface_register(struct class_interface *class_intf)
list_add_tail(&class_intf->node, &parent->interfaces);
if (class_intf->add) {
list_for_each_entry(class_dev, &parent->children, node)
- class_intf->add(class_dev);
+ class_intf->add(class_dev, class_intf);
}
up(&parent->sem);
@@ -747,7 +798,7 @@ void class_interface_unregister(struct class_interface *class_intf)
list_del_init(&class_intf->node);
if (class_intf->remove) {
list_for_each_entry(class_dev, &parent->children, node)
- class_intf->remove(class_dev);
+ class_intf->remove(class_dev, class_intf);
}
up(&parent->sem);