Linux Kernel设备驱动模型之总线添加驱动

设备驱动之总线添加驱动： /**  * bus_add_driver - Add a driver to the bus.  * @drv: driver.  */ int bus_add_driver(struct device_driver *drv) {  struct bus_type *bus;  struct driver_private *priv;  int error = 0;

 bus = bus_get(drv->bus);  if (!bus)   return -EINVAL;

 pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name);

 priv = kzalloc(sizeof(*priv), GFP_KERNEL);  if (!priv) {   error = -ENOMEM;   goto out_put_bus;  }  klist_init(&priv->klist_devices, NULL, NULL);  priv->driver = drv;  drv->p = priv;  priv->kobj.kset = bus->p->drivers_kset;  error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL,          "%s", drv->name);  if (error)   goto out_unregister;

 klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers);  if (drv->bus->p->drivers_autoprobe) {   if (driver_allows_async_probing(drv)) {    pr_debug("bus: '%s': probing driver %s asynchronously\n",     drv->bus->name, drv->name);    async_schedule(driver_attach_async, drv);   } else {    error = driver_attach(drv);    if (error)     goto out_unregister;   }  }  module_add_driver(drv->owner, drv);

 error = driver_create_file(drv, &driver_attr_uevent);  if (error) {   printk(KERN_ERR "%s: uevent attr (%s) failed\n",    __func__, drv->name);  }  error = driver_add_groups(drv, bus->drv_groups);  if (error) {   /* How the hell do we get out of this pickle? Give up */   printk(KERN_ERR "%s: driver_create_groups(%s) failed\n",    __func__, drv->name);  }

 if (!drv->suppress_bind_attrs) {   error = add_bind_files(drv);   if (error) {    /* Ditto */    printk(KERN_ERR "%s: add_bind_files(%s) failed\n",     __func__, drv->name);   }  }

 return 0;

out_unregister:  kobject_put(&priv->kobj);  kfree(drv->p);  drv->p = NULL; out_put_bus:  bus_put(bus);  return error; }