diff options
| -rw-r--r-- | drivers/base/class.c | 125 | ||||
| -rw-r--r-- | include/linux/device.h | 13 |
2 files changed, 91 insertions, 47 deletions
diff --git a/drivers/base/class.c b/drivers/base/class.c index 3cf6eb3..c3e5697 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -99,7 +99,8 @@ 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 +166,25 @@ 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 +313,12 @@ 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 +396,18 @@ 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; @@ -476,37 +494,42 @@ 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->owner; + 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); @@ -520,7 +543,7 @@ int class_device_add(struct class_device *class_dev) } attr->attr.name = "dev"; attr->attr.mode = S_IRUGO; - attr->attr.owner = parent->owner; + attr->attr.owner = parent_class->owner; attr->show = show_dev; class_device_create_file(class_dev, attr); class_dev->devt_attr = attr; @@ -538,18 +561,20 @@ int class_device_add(struct class_device *class_dev) 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, class_intf); - up(&parent->sem); + up(&parent_class->sem); } 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; @@ -564,21 +589,28 @@ 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; @@ -597,6 +629,9 @@ 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); @@ -614,17 +649,18 @@ 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, class_intf); - up(&parent->sem); + up(&parent_class->sem); } if (class_dev->dev) { @@ -640,8 +676,8 @@ 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); } @@ -721,7 +757,8 @@ 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); } diff --git a/include/linux/device.h b/include/linux/device.h index e86a580..226e550 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -213,7 +213,11 @@ struct class_device { struct class_device_attribute uevent_attr; struct device * dev; /* not necessary, but nice to have */ void * class_data; /* class-specific data */ + struct class_device *parent; /* parent of this child device, if there is one */ + void (*release)(struct class_device *dev); + int (*hotplug)(struct class_device *dev, char **envp, + int num_envp, char *buffer, int buffer_size); char class_id[BUS_ID_SIZE]; /* unique to this class */ }; @@ -261,9 +265,12 @@ extern void class_interface_unregister(struct class_interface *); extern struct class *class_create(struct module *owner, char *name); extern void class_destroy(struct class *cls); -extern struct class_device *class_device_create(struct class *cls, dev_t devt, - struct device *device, char *fmt, ...) - __attribute__((format(printf,4,5))); +extern struct class_device *class_device_create(struct class *cls, + struct class_device *parent, + dev_t devt, + struct device *device, + char *fmt, ...) + __attribute__((format(printf,5,6))); extern void class_device_destroy(struct class *cls, dev_t devt); |