#include <linux/init.h>
#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)
{
struct class_attribute * class_attr = to_class_attr(attr);
struct class * dc = to_class(kobj);
- ssize_t ret = 0;
+ ssize_t ret = -EIO;
if (class_attr->show)
ret = class_attr->show(dc, buf);
{
struct class_attribute * class_attr = to_class_attr(attr);
struct class * dc = to_class(kobj);
- ssize_t ret = 0;
+ ssize_t ret = -EIO;
if (class_attr->store)
ret = class_attr->store(dc, buf, count);
sysfs_remove_file(&cls->subsys.kset.kobj, &attr->attr);
}
-struct class * class_get(struct class * cls)
+static struct class *class_get(struct class *cls)
{
if (cls)
return container_of(subsys_get(&cls->subsys), struct class, subsys);
return NULL;
}
-void class_put(struct class * cls)
+static void class_put(struct class * cls)
{
- subsys_put(&cls->subsys);
+ if (cls)
+ subsys_put(&cls->subsys);
}
subsystem_unregister(&cls->subsys);
}
+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_uevent(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
+ * @name: pointer to a string for the name of this class.
+ *
+ * This is used to create a struct class pointer that can then be used
+ * in calls to class_device_create().
+ *
+ * Note, the pointer created here is to be destroyed when finished by
+ * making a call to class_destroy().
+ */
+struct class *class_create(struct module *owner, char *name)
+{
+ struct class *cls;
+ int retval;
+
+ cls = kzalloc(sizeof(*cls), GFP_KERNEL);
+ if (!cls) {
+ retval = -ENOMEM;
+ goto error;
+ }
+
+ cls->name = name;
+ cls->owner = owner;
+ cls->class_release = class_create_release;
+ cls->release = class_device_create_release;
+
+ retval = class_register(cls);
+ if (retval)
+ goto error;
+
+ return cls;
+
+error:
+ kfree(cls);
+ return ERR_PTR(retval);
+}
+
+/**
+ * class_destroy - destroys a struct class structure
+ * @cs: pointer to the struct class that is to be destroyed
+ *
+ * Note, the pointer to be destroyed must have been created with a call
+ * to class_create().
+ */
+void class_destroy(struct class *cls)
+{
+ if ((cls == NULL) || (IS_ERR(cls)))
+ return;
+
+ class_unregister(cls);
+}
/* Class Device Stuff */
pr_debug("device class '%s': release.\n", cd->class_id);
- if (cls->release)
+ kfree(cd->devt_attr);
+ cd->devt_attr = NULL;
+
+ 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);
.release = class_dev_release,
};
-static int class_hotplug_filter(struct kset *kset, struct kobject *kobj)
+static int class_uevent_filter(struct kset *kset, struct kobject *kobj)
{
struct kobj_type *ktype = get_ktype(kobj);
return 0;
}
-static const char *class_hotplug_name(struct kset *kset, struct kobject *kobj)
+static const char *class_uevent_name(struct kset *kset, struct kobject *kobj)
{
struct class_device *class_dev = to_class_dev(kobj);
return class_dev->class->name;
}
-static int class_hotplug(struct kset *kset, struct kobject *kobj, char **envp,
+static int class_uevent(struct kset *kset, struct kobject *kobj, char **envp,
int num_envp, char *buffer, int buffer_size)
{
struct class_device *class_dev = to_class_dev(kobj);
struct device *dev = class_dev->dev;
char *path = kobject_get_path(&dev->kobj, GFP_KERNEL);
- add_hotplug_env_var(envp, num_envp, &i, buffer, buffer_size,
- &length, "PHYSDEVPATH=%s", path);
+ add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
+ &length, "PHYSDEVPATH=%s", path);
kfree(path);
if (dev->bus)
- add_hotplug_env_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "PHYSDEVBUS=%s", dev->bus->name);
+ add_uevent_var(envp, num_envp, &i,
+ buffer, buffer_size, &length,
+ "PHYSDEVBUS=%s", dev->bus->name);
if (dev->driver)
- add_hotplug_env_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "PHYSDEVDRIVER=%s", dev->driver->name);
+ add_uevent_var(envp, num_envp, &i,
+ buffer, buffer_size, &length,
+ "PHYSDEVDRIVER=%s", dev->driver->name);
}
if (MAJOR(class_dev->devt)) {
- add_hotplug_env_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "MAJOR=%u", MAJOR(class_dev->devt));
+ add_uevent_var(envp, num_envp, &i,
+ buffer, buffer_size, &length,
+ "MAJOR=%u", MAJOR(class_dev->devt));
- add_hotplug_env_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "MINOR=%u", MINOR(class_dev->devt));
+ add_uevent_var(envp, num_envp, &i,
+ buffer, buffer_size, &length,
+ "MINOR=%u", MINOR(class_dev->devt));
}
/* terminate, set to next free slot, shrink available space */
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->uevent) {
+ /* have the class device specific function add its stuff */
+ retval = class_dev->uevent(class_dev, envp, num_envp,
+ buffer, buffer_size);
+ if (retval)
+ pr_debug("class_dev->uevent() returned %d\n", retval);
+ } else if (class_dev->class->uevent) {
+ /* have the class specific function add its stuff */
+ retval = class_dev->class->uevent(class_dev, envp, num_envp,
+ buffer, buffer_size);
+ if (retval)
+ pr_debug("class->uevent() returned %d\n", retval);
}
return retval;
}
-static struct kset_hotplug_ops class_hotplug_ops = {
- .filter = class_hotplug_filter,
- .name = class_hotplug_name,
- .hotplug = class_hotplug,
+static struct kset_uevent_ops class_uevent_ops = {
+ .filter = class_uevent_filter,
+ .name = class_uevent_name,
+ .uevent = class_uevent,
};
-static decl_subsys(class_obj, &ktype_class_device, &class_hotplug_ops);
+static decl_subsys(class_obj, &ktype_class_device, &class_uevent_ops);
static int class_device_add_attrs(struct class_device * cd)
}
}
+static int class_device_add_groups(struct class_device * cd)
+{
+ int i;
+ int error = 0;
+
+ if (cd->groups) {
+ for (i = 0; cd->groups[i]; i++) {
+ error = sysfs_create_group(&cd->kobj, cd->groups[i]);
+ if (error) {
+ while (--i >= 0)
+ sysfs_remove_group(&cd->kobj, cd->groups[i]);
+ goto out;
+ }
+ }
+ }
+out:
+ return error;
+}
+
+static void class_device_remove_groups(struct class_device * cd)
+{
+ int i;
+ if (cd->groups) {
+ for (i = 0; cd->groups[i]; i++) {
+ sysfs_remove_group(&cd->kobj, cd->groups[i]);
+ }
+ }
+}
+
static ssize_t show_dev(struct class_device *class_dev, char *buf)
{
return print_dev_t(buf, class_dev->devt);
}
-static CLASS_DEVICE_ATTR(dev, S_IRUGO, show_dev, NULL);
+
+static ssize_t store_uevent(struct class_device *class_dev,
+ const char *buf, size_t count)
+{
+ kobject_uevent(&class_dev->kobj, KOBJ_ADD);
+ return count;
+}
void class_device_initialize(struct class_device *class_dev)
{
INIT_LIST_HEAD(&class_dev->node);
}
+static char *make_class_name(struct class_device *class_dev)
+{
+ char *name;
+ int size;
+
+ size = strlen(class_dev->class->name) +
+ strlen(kobject_name(&class_dev->kobj)) + 2;
+
+ name = kmalloc(size, GFP_KERNEL);
+ if (!name)
+ return ERR_PTR(-ENOMEM);
+
+ strcpy(name, class_dev->class->name);
+ strcat(name, ":");
+ strcat(name, kobject_name(&class_dev->kobj));
+ return name;
+}
+
int class_device_add(struct class_device *class_dev)
{
- struct class * parent = NULL;
- struct class_interface * class_intf;
- int error;
+ struct class *parent_class = NULL;
+ struct class_device *parent_class_dev = NULL;
+ struct class_interface *class_intf;
+ char *class_name = NULL;
+ int error = -EINVAL;
class_dev = class_device_get(class_dev);
if (!class_dev)
return -EINVAL;
- if (!strlen(class_dev->class_id)) {
- error = -EINVAL;
- goto register_done;
- }
+ if (!strlen(class_dev->class_id))
+ goto out1;
+
+ parent_class = class_get(class_dev->class);
+ if (!parent_class)
+ goto out1;
- parent = class_get(class_dev->class);
+ 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 ((error = kobject_add(&class_dev->kobj)))
- goto register_done;
-
- /* now take care of our own registration */
- if (parent) {
- down(&parent->sem);
- list_add_tail(&class_dev->node, &parent->children);
- list_for_each_entry(class_intf, &parent->interfaces, node)
- if (class_intf->add)
- class_intf->add(class_dev);
- up(&parent->sem);
+ error = kobject_set_name(&class_dev->kobj, "%s", class_dev->class_id);
+ if (error)
+ goto out2;
+
+ if (parent_class_dev)
+ class_dev->kobj.parent = &parent_class_dev->kobj;
+ else
+ class_dev->kobj.parent = &parent_class->subsys.kset.kobj;
+
+ error = kobject_add(&class_dev->kobj);
+ if (error)
+ goto out2;
+
+ /* 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;
+ error = class_device_create_file(class_dev, &class_dev->uevent_attr);
+ if (error)
+ goto out3;
+
+ if (MAJOR(class_dev->devt)) {
+ struct class_device_attribute *attr;
+ attr = kzalloc(sizeof(*attr), GFP_KERNEL);
+ if (!attr) {
+ error = -ENOMEM;
+ goto out4;
+ }
+ attr->attr.name = "dev";
+ attr->attr.mode = S_IRUGO;
+ attr->attr.owner = parent_class->owner;
+ attr->show = show_dev;
+ error = class_device_create_file(class_dev, attr);
+ if (error) {
+ kfree(attr);
+ goto out4;
+ }
+
+ class_dev->devt_attr = attr;
}
- if (MAJOR(class_dev->devt))
- class_device_create_file(class_dev, &class_device_attr_dev);
+ error = class_device_add_attrs(class_dev);
+ if (error)
+ goto out5;
- class_device_add_attrs(class_dev);
- if (class_dev->dev)
- sysfs_create_link(&class_dev->kobj,
- &class_dev->dev->kobj, "device");
+ if (class_dev->dev) {
+ class_name = make_class_name(class_dev);
+ error = sysfs_create_link(&class_dev->kobj,
+ &class_dev->dev->kobj, "device");
+ if (error)
+ goto out6;
+ error = sysfs_create_link(&class_dev->dev->kobj, &class_dev->kobj,
+ class_name);
+ if (error)
+ goto out7;
+ }
- kobject_hotplug(&class_dev->kobj, KOBJ_ADD);
- register_done:
- if (error && parent)
- class_put(parent);
+ error = class_device_add_groups(class_dev);
+ if (error)
+ goto out8;
+
+ kobject_uevent(&class_dev->kobj, KOBJ_ADD);
+
+ /* notify any interfaces this device is now here */
+ 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, class_intf);
+ }
+ up(&parent_class->sem);
+
+ goto out1;
+
+ out8:
+ if (class_dev->dev)
+ sysfs_remove_link(&class_dev->kobj, class_name);
+ out7:
+ if (class_dev->dev)
+ sysfs_remove_link(&class_dev->kobj, "device");
+ out6:
+ class_device_remove_attrs(class_dev);
+ out5:
+ if (class_dev->devt_attr)
+ class_device_remove_file(class_dev, class_dev->devt_attr);
+ out4:
+ class_device_remove_file(class_dev, &class_dev->uevent_attr);
+ out3:
+ kobject_del(&class_dev->kobj);
+ out2:
+ if(parent_class_dev)
+ class_device_put(parent_class_dev);
+ class_put(parent_class);
+ out1:
class_device_put(class_dev);
+ kfree(class_name);
return error;
}
return class_device_add(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, 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,
+ struct class_device *parent,
+ dev_t devt,
+ struct device *device, char *fmt, ...)
+{
+ va_list args;
+ struct class_device *class_dev = NULL;
+ int retval = -ENODEV;
+
+ if (cls == NULL || IS_ERR(cls))
+ goto error;
+
+ class_dev = kzalloc(sizeof(*class_dev), GFP_KERNEL);
+ if (!class_dev) {
+ retval = -ENOMEM;
+ goto error;
+ }
+
+ 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->uevent = class_device_create_uevent;
+
+ va_start(args, fmt);
+ vsnprintf(class_dev->class_id, BUS_ID_SIZE, fmt, args);
+ va_end(args);
+ retval = class_device_register(class_dev);
+ if (retval)
+ goto error;
+
+ return class_dev;
+
+error:
+ kfree(class_dev);
+ return ERR_PTR(retval);
+}
+
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)
+ if (class_dev->dev) {
+ class_name = make_class_name(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);
+ class_device_remove_groups(class_dev);
- kobject_hotplug(&class_dev->kobj, KOBJ_REMOVE);
+ kobject_uevent(&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);
}
void class_device_unregister(struct class_device *class_dev)
class_device_put(class_dev);
}
+/**
+ * class_device_destroy - removes a class device that was created with class_device_create()
+ * @cls: the pointer to the struct class that this device was registered * with.
+ * @dev: the dev_t of the device that was previously registered.
+ *
+ * This call unregisters and cleans up a class device that was created with a
+ * call to class_device_create()
+ */
+void class_device_destroy(struct class *cls, dev_t devt)
+{
+ struct class_device *class_dev = NULL;
+ struct class_device *class_dev_tmp;
+
+ down(&cls->sem);
+ list_for_each_entry(class_dev_tmp, &cls->children, node) {
+ if (class_dev_tmp->devt == devt) {
+ class_dev = class_dev_tmp;
+ break;
+ }
+ }
+ up(&cls->sem);
+
+ if (class_dev)
+ class_device_unregister(class_dev);
+}
+
int class_device_rename(struct class_device *class_dev, char *new_name)
{
int error = 0;
+ char *old_class_name = NULL, *new_class_name = NULL;
class_dev = class_device_get(class_dev);
if (!class_dev)
pr_debug("CLASS: renaming '%s' to '%s'\n", class_dev->class_id,
new_name);
+ if (class_dev->dev)
+ old_class_name = make_class_name(class_dev);
+
strlcpy(class_dev->class_id, new_name, KOBJ_NAME_LEN);
error = kobject_rename(&class_dev->kobj, new_name);
+ if (class_dev->dev) {
+ new_class_name = make_class_name(class_dev);
+ sysfs_create_link(&class_dev->dev->kobj, &class_dev->kobj,
+ new_class_name);
+ sysfs_remove_link(&class_dev->dev->kobj, old_class_name);
+ }
class_device_put(class_dev);
+ kfree(old_class_name);
+ kfree(new_class_name);
+
return error;
}
void class_device_put(struct class_device *class_dev)
{
- kobject_put(&class_dev->kobj);
+ if (class_dev)
+ kobject_put(&class_dev->kobj);
}
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);
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);
EXPORT_SYMBOL_GPL(class_remove_file);
EXPORT_SYMBOL_GPL(class_register);
EXPORT_SYMBOL_GPL(class_unregister);
-EXPORT_SYMBOL_GPL(class_get);
-EXPORT_SYMBOL_GPL(class_put);
+EXPORT_SYMBOL_GPL(class_create);
+EXPORT_SYMBOL_GPL(class_destroy);
EXPORT_SYMBOL_GPL(class_device_register);
EXPORT_SYMBOL_GPL(class_device_unregister);
EXPORT_SYMBOL_GPL(class_device_del);
EXPORT_SYMBOL_GPL(class_device_get);
EXPORT_SYMBOL_GPL(class_device_put);
+EXPORT_SYMBOL_GPL(class_device_create);
+EXPORT_SYMBOL_GPL(class_device_destroy);
EXPORT_SYMBOL_GPL(class_device_create_file);
EXPORT_SYMBOL_GPL(class_device_remove_file);
EXPORT_SYMBOL_GPL(class_device_create_bin_file);