u-boot device_0f_to_plat函数

 //

//递归函数来设定设备dev的数据，

1. 分配设备的私有数据

int device_of_to_plat(struct udevice *dev) {     const struct driver *drv;     int ret;
    if (!dev)         return -EINVAL;
    if (dev_get_flags(dev) & DM_FLAG_PLATDATA_VALID)         return 0;
    /*      * This is not needed if binding is disabled, since data is allocated      * at build time.      */     if (!CONFIG_IS_ENABLED(OF_PLATDATA_NO_BIND)) {         /* Ensure all parents have ofdata */         if (dev->parent) {             ret = device_of_to_plat(dev->parent);             if (ret)                 goto fail;
            /*              * The device might have already been probed during              * the call to device_probe() on its parent device              * (e.g. PCI bridge devices). Test the flags again              * so that we don't mess up the device.              */             if (dev_get_flags(dev) & DM_FLAG_PLATDATA_VALID)                 return 0;         } //设定设备dev的私有数据
        ret = device_alloc_priv(dev);         if (ret)             goto fail;     }     drv = dev->driver;     assert(drv);   //调用设备驱动程序的操作of_to_plat
    if (drv->of_to_plat &&         (CONFIG_IS_ENABLED(OF_PLATDATA) || dev_has_ofnode(dev))) {         ret = drv->of_to_plat(dev);         if (ret)             goto fail;     }   //设定设备dev的flag
    dev_or_flags(dev, DM_FLAG_PLATDATA_VALID);
    return 0; fail:     device_free(dev);
    return ret; }