QCA8K_REG_ATU_FUNC
ret = qca8k_write(priv, QCA8K_REG_ATU_FUNC, reg);
ret = qca8k_busy_wait(priv, QCA8K_REG_ATU_FUNC, QCA8K_ATU_FUNC_BUSY);
ret = qca8k_read(priv, QCA8K_REG_ATU_FUNC, ®);