*
*/
-#include <linux/config.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/string.h>
+#include <linux/kdev_t.h>
#include <asm/semaphore.h>
* sysfs bindings for devices.
*/
+/**
+ * dev_driver_string - Return a device's driver name, if at all possible
+ * @dev: struct device to get the name of
+ *
+ * Will return the device's driver's name if it is bound to a device. If
+ * the device is not bound to a device, it will return the name of the bus
+ * it is attached to. If it is not attached to a bus either, an empty
+ * string will be returned.
+ */
+const char *dev_driver_string(struct device *dev)
+{
+ return dev->driver ? dev->driver->name :
+ (dev->bus ? dev->bus->name : "");
+}
+EXPORT_SYMBOL_GPL(dev_driver_string);
+
#define to_dev(obj) container_of(obj, struct device, kobj)
#define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)
-extern struct attribute * dev_default_attrs[];
-
static ssize_t
dev_attr_show(struct kobject * kobj, struct attribute * attr, char * buf)
{
struct device_attribute * dev_attr = to_dev_attr(attr);
struct device * dev = to_dev(kobj);
- ssize_t ret = 0;
+ ssize_t ret = -EIO;
if (dev_attr->show)
- ret = dev_attr->show(dev, buf);
+ ret = dev_attr->show(dev, dev_attr, buf);
return ret;
}
{
struct device_attribute * dev_attr = to_dev_attr(attr);
struct device * dev = to_dev(kobj);
- ssize_t ret = 0;
+ ssize_t ret = -EIO;
if (dev_attr->store)
- ret = dev_attr->store(dev, buf, count);
+ ret = dev_attr->store(dev, dev_attr, buf, count);
return ret;
}
static struct kobj_type ktype_device = {
.release = device_release,
.sysfs_ops = &dev_sysfs_ops,
- .default_attrs = dev_default_attrs,
};
-static int dev_hotplug_filter(struct kset *kset, struct kobject *kobj)
+static int dev_uevent_filter(struct kset *kset, struct kobject *kobj)
{
struct kobj_type *ktype = get_ktype(kobj);
struct device *dev = to_dev(kobj);
if (dev->bus)
return 1;
+ if (dev->class)
+ return 1;
}
return 0;
}
-static char *dev_hotplug_name(struct kset *kset, struct kobject *kobj)
+static const char *dev_uevent_name(struct kset *kset, struct kobject *kobj)
{
struct device *dev = to_dev(kobj);
- return dev->bus->name;
+ if (dev->bus)
+ return dev->bus->name;
+ if (dev->class)
+ return dev->class->name;
+ return NULL;
}
-static int dev_hotplug(struct kset *kset, struct kobject *kobj, char **envp,
+static int dev_uevent(struct kset *kset, struct kobject *kobj, char **envp,
int num_envp, char *buffer, int buffer_size)
{
struct device *dev = to_dev(kobj);
+ int i = 0;
+ int length = 0;
int retval = 0;
- if (dev->bus->hotplug) {
+ /* add the major/minor if present */
+ if (MAJOR(dev->devt)) {
+ add_uevent_var(envp, num_envp, &i,
+ buffer, buffer_size, &length,
+ "MAJOR=%u", MAJOR(dev->devt));
+ add_uevent_var(envp, num_envp, &i,
+ buffer, buffer_size, &length,
+ "MINOR=%u", MINOR(dev->devt));
+ }
+
+ /* add bus name of physical device */
+ if (dev->bus)
+ add_uevent_var(envp, num_envp, &i,
+ buffer, buffer_size, &length,
+ "PHYSDEVBUS=%s", dev->bus->name);
+
+ /* add driver name of physical device */
+ if (dev->driver)
+ add_uevent_var(envp, num_envp, &i,
+ buffer, buffer_size, &length,
+ "PHYSDEVDRIVER=%s", dev->driver->name);
+
+ /* terminate, set to next free slot, shrink available space */
+ envp[i] = NULL;
+ envp = &envp[i];
+ num_envp -= i;
+ buffer = &buffer[length];
+ buffer_size -= length;
+
+ if (dev->bus && dev->bus->uevent) {
/* have the bus specific function add its stuff */
- retval = dev->bus->hotplug (dev, envp, num_envp, buffer, buffer_size);
+ retval = dev->bus->uevent(dev, envp, num_envp, buffer, buffer_size);
if (retval) {
- pr_debug ("%s - hotplug() returned %d\n",
+ pr_debug ("%s - uevent() returned %d\n",
__FUNCTION__, retval);
}
}
return retval;
}
-static struct kset_hotplug_ops device_hotplug_ops = {
- .filter = dev_hotplug_filter,
- .name = dev_hotplug_name,
- .hotplug = dev_hotplug,
+static struct kset_uevent_ops device_uevent_ops = {
+ .filter = dev_uevent_filter,
+ .name = dev_uevent_name,
+ .uevent = dev_uevent,
};
-/**
- * device_subsys - structure to be registered with kobject core.
+static ssize_t store_uevent(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ kobject_uevent(&dev->kobj, KOBJ_ADD);
+ return count;
+}
+
+static ssize_t show_dev(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ return print_dev_t(buf, dev->devt);
+}
+
+/*
+ * devices_subsys - structure to be registered with kobject core.
*/
-decl_subsys(devices, &ktype_device, &device_hotplug_ops);
+decl_subsys(devices, &ktype_device, &device_uevent_ops);
/**
}
}
+static void klist_children_get(struct klist_node *n)
+{
+ struct device *dev = container_of(n, struct device, knode_parent);
+
+ get_device(dev);
+}
+
+static void klist_children_put(struct klist_node *n)
+{
+ struct device *dev = container_of(n, struct device, knode_parent);
+
+ put_device(dev);
+}
+
/**
* device_initialize - init device structure.
{
kobj_set_kset_s(dev, devices_subsys);
kobject_init(&dev->kobj);
- INIT_LIST_HEAD(&dev->node);
- INIT_LIST_HEAD(&dev->children);
- INIT_LIST_HEAD(&dev->driver_list);
- INIT_LIST_HEAD(&dev->bus_list);
+ klist_init(&dev->klist_children, klist_children_get,
+ klist_children_put);
INIT_LIST_HEAD(&dev->dma_pools);
+ INIT_LIST_HEAD(&dev->node);
+ init_MUTEX(&dev->sem);
+ device_init_wakeup(dev, 0);
}
/**
*/
int device_add(struct device *dev)
{
- struct device * parent;
- int error;
+ struct device *parent = NULL;
+ char *class_name = NULL;
+ int error = -EINVAL;
dev = get_device(dev);
if (!dev || !strlen(dev->bus_id))
- return -EINVAL;
+ goto Error;
parent = get_device(dev->parent);
pr_debug("DEV: registering device: ID = '%s'\n", dev->bus_id);
/* first, register with generic layer. */
- kobject_set_name(&dev->kobj, dev->bus_id);
+ kobject_set_name(&dev->kobj, "%s", dev->bus_id);
if (parent)
dev->kobj.parent = &parent->kobj;
if ((error = kobject_add(&dev->kobj)))
goto Error;
+
+ dev->uevent_attr.attr.name = "uevent";
+ dev->uevent_attr.attr.mode = S_IWUSR;
+ if (dev->driver)
+ dev->uevent_attr.attr.owner = dev->driver->owner;
+ dev->uevent_attr.store = store_uevent;
+ device_create_file(dev, &dev->uevent_attr);
+
+ if (MAJOR(dev->devt)) {
+ struct device_attribute *attr;
+ attr = kzalloc(sizeof(*attr), GFP_KERNEL);
+ if (!attr) {
+ error = -ENOMEM;
+ goto PMError;
+ }
+ attr->attr.name = "dev";
+ attr->attr.mode = S_IRUGO;
+ if (dev->driver)
+ attr->attr.owner = dev->driver->owner;
+ attr->show = show_dev;
+ error = device_create_file(dev, attr);
+ if (error) {
+ kfree(attr);
+ goto attrError;
+ }
+
+ dev->devt_attr = attr;
+ }
+
+ if (dev->class) {
+ sysfs_create_link(&dev->kobj, &dev->class->subsys.kset.kobj,
+ "subsystem");
+ sysfs_create_link(&dev->class->subsys.kset.kobj, &dev->kobj,
+ dev->bus_id);
+
+ sysfs_create_link(&dev->kobj, &dev->parent->kobj, "device");
+ class_name = make_class_name(dev->class->name, &dev->kobj);
+ sysfs_create_link(&dev->parent->kobj, &dev->kobj, class_name);
+ }
+
if ((error = device_pm_add(dev)))
goto PMError;
if ((error = bus_add_device(dev)))
goto BusError;
- down_write(&devices_subsys.rwsem);
+ kobject_uevent(&dev->kobj, KOBJ_ADD);
+ bus_attach_device(dev);
if (parent)
- list_add_tail(&dev->node, &parent->children);
- up_write(&devices_subsys.rwsem);
+ klist_add_tail(&dev->knode_parent, &parent->klist_children);
+
+ if (dev->class) {
+ /* tie the class to the device */
+ down(&dev->class->sem);
+ list_add_tail(&dev->node, &dev->class->devices);
+ up(&dev->class->sem);
+ }
/* notify platform of device entry */
if (platform_notify)
platform_notify(dev);
Done:
+ kfree(class_name);
put_device(dev);
return error;
BusError:
device_pm_remove(dev);
PMError:
+ if (dev->devt_attr) {
+ device_remove_file(dev, dev->devt_attr);
+ kfree(dev->devt_attr);
+ }
+ attrError:
+ kobject_uevent(&dev->kobj, KOBJ_REMOVE);
kobject_del(&dev->kobj);
Error:
if (parent)
*/
void put_device(struct device * dev)
{
- kobject_put(&dev->kobj);
+ if (dev)
+ kobject_put(&dev->kobj);
}
void device_del(struct device * dev)
{
struct device * parent = dev->parent;
+ char *class_name = NULL;
- down_write(&devices_subsys.rwsem);
if (parent)
+ klist_del(&dev->knode_parent);
+ if (dev->devt_attr)
+ device_remove_file(dev, dev->devt_attr);
+ if (dev->class) {
+ sysfs_remove_link(&dev->kobj, "subsystem");
+ sysfs_remove_link(&dev->class->subsys.kset.kobj, dev->bus_id);
+ class_name = make_class_name(dev->class->name, &dev->kobj);
+ sysfs_remove_link(&dev->kobj, "device");
+ sysfs_remove_link(&dev->parent->kobj, class_name);
+ kfree(class_name);
+ down(&dev->class->sem);
list_del_init(&dev->node);
- up_write(&devices_subsys.rwsem);
+ up(&dev->class->sem);
+ }
+ device_remove_file(dev, &dev->uevent_attr);
/* Notify the platform of the removal, in case they
* need to do anything...
platform_notify_remove(dev);
bus_remove_device(dev);
device_pm_remove(dev);
+ kobject_uevent(&dev->kobj, KOBJ_REMOVE);
kobject_del(&dev->kobj);
if (parent)
put_device(parent);
}
+static struct device * next_device(struct klist_iter * i)
+{
+ struct klist_node * n = klist_next(i);
+ return n ? container_of(n, struct device, knode_parent) : NULL;
+}
+
/**
* device_for_each_child - device child iterator.
- * @dev: parent struct device.
+ * @parent: parent struct device.
* @data: data for the callback.
* @fn: function to be called for each device.
*
- * Iterate over @dev's child devices, and call @fn for each,
+ * Iterate over @parent's child devices, and call @fn for each,
* passing it @data.
*
* We check the return of @fn each time. If it returns anything
* other than 0, we break out and return that value.
*/
-int device_for_each_child(struct device * dev, void * data,
+int device_for_each_child(struct device * parent, void * data,
int (*fn)(struct device *, void *))
{
+ struct klist_iter i;
struct device * child;
int error = 0;
- down_read(&devices_subsys.rwsem);
- list_for_each_entry(child, &dev->children, node) {
- if((error = fn(child, data)))
- break;
- }
- up_read(&devices_subsys.rwsem);
+ klist_iter_init(&parent->klist_children, &i);
+ while ((child = next_device(&i)) && !error)
+ error = fn(child, data);
+ klist_iter_exit(&i);
return error;
}
+int __init devices_init(void)
+{
+ return subsystem_register(&devices_subsys);
+}
+
+EXPORT_SYMBOL_GPL(device_for_each_child);
+
+EXPORT_SYMBOL_GPL(device_initialize);
+EXPORT_SYMBOL_GPL(device_add);
+EXPORT_SYMBOL_GPL(device_register);
+
+EXPORT_SYMBOL_GPL(device_del);
+EXPORT_SYMBOL_GPL(device_unregister);
+EXPORT_SYMBOL_GPL(get_device);
+EXPORT_SYMBOL_GPL(put_device);
+
+EXPORT_SYMBOL_GPL(device_create_file);
+EXPORT_SYMBOL_GPL(device_remove_file);
+
+
+static void device_create_release(struct device *dev)
+{
+ pr_debug("%s called for %s\n", __FUNCTION__, dev->bus_id);
+ kfree(dev);
+}
+
/**
- * device_find - locate device on a bus by name.
- * @name: name of the device.
- * @bus: bus to scan for the device.
+ * device_create - creates a device and registers it with sysfs
+ * @class: pointer to the struct class that this device should be registered to
+ * @parent: pointer to the parent struct device of this new device, if any
+ * @devt: the dev_t for the char device to be added
+ * @fmt: string for the device's name
+ *
+ * This function can be used by char device classes. A struct device
+ * will be created in sysfs, registered to the specified class.
*
- * Call kset_find_obj() to iterate over list of devices on
- * a bus to find device by name. Return device if found.
+ * 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 device is passed in, the newly created
+ * struct device will be a child of that device in sysfs.
+ * The pointer to the struct device will be returned from the call.
+ * Any further sysfs files that might be required can be created using this
+ * pointer.
*
- * Note that kset_find_obj increments device's reference count.
+ * Note: the struct class passed to this function must have previously
+ * been created with a call to class_create().
*/
-struct device *device_find(const char *name, struct bus_type *bus)
+struct device *device_create(struct class *class, struct device *parent,
+ dev_t devt, char *fmt, ...)
{
- struct kobject *k = kset_find_obj(&bus->devices, name);
- if (k)
- return to_dev(k);
- return NULL;
-}
+ va_list args;
+ struct device *dev = NULL;
+ int retval = -ENODEV;
+
+ if (class == NULL || IS_ERR(class))
+ goto error;
+ if (parent == NULL) {
+ printk(KERN_WARNING "%s does not work yet for NULL parents\n", __FUNCTION__);
+ goto error;
+ }
-int __init devices_init(void)
-{
- return subsystem_register(&devices_subsys);
-}
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+ if (!dev) {
+ retval = -ENOMEM;
+ goto error;
+ }
+
+ dev->devt = devt;
+ dev->class = class;
+ dev->parent = parent;
+ dev->release = device_create_release;
+
+ va_start(args, fmt);
+ vsnprintf(dev->bus_id, BUS_ID_SIZE, fmt, args);
+ va_end(args);
+ retval = device_register(dev);
+ if (retval)
+ goto error;
-EXPORT_SYMBOL(device_for_each_child);
+ return dev;
-EXPORT_SYMBOL(device_initialize);
-EXPORT_SYMBOL(device_add);
-EXPORT_SYMBOL(device_register);
+error:
+ kfree(dev);
+ return ERR_PTR(retval);
+}
+EXPORT_SYMBOL_GPL(device_create);
+
+/**
+ * device_destroy - removes a device that was created with device_create()
+ * @class: pointer to the struct class that this device was registered with
+ * @devt: the dev_t of the device that was previously registered
+ *
+ * This call unregisters and cleans up a device that was created with a
+ * call to device_create().
+ */
+void device_destroy(struct class *class, dev_t devt)
+{
+ struct device *dev = NULL;
+ struct device *dev_tmp;
-EXPORT_SYMBOL(device_del);
-EXPORT_SYMBOL(device_unregister);
-EXPORT_SYMBOL(get_device);
-EXPORT_SYMBOL(put_device);
-EXPORT_SYMBOL(device_find);
+ down(&class->sem);
+ list_for_each_entry(dev_tmp, &class->devices, node) {
+ if (dev_tmp->devt == devt) {
+ dev = dev_tmp;
+ break;
+ }
+ }
+ up(&class->sem);
-EXPORT_SYMBOL(device_create_file);
-EXPORT_SYMBOL(device_remove_file);
+ if (dev)
+ device_unregister(dev);
+}
+EXPORT_SYMBOL_GPL(device_destroy);