TUSB_DEV_CONF
conf = musb_readl(tbase, TUSB_DEV_CONF);
musb_writel(tbase, TUSB_DEV_CONF, conf);
dev_conf = musb_readl(tbase, TUSB_DEV_CONF);
musb_writel(tbase, TUSB_DEV_CONF, dev_conf);