Passing html fileupload value to a c# method in MVC 5 to bind to a partial view

Question

I am new to MVC (coming from WebForm background). I have a main view which contains 2 tabs that need the same model for table view. However, I created a partial view containing table structure to display data records in the 2 tabs asynchronously. One tab gets its data from CSV while the other gets from SQL Server based on user's selection but having the same model.

I have the screenshot of the concept below: The box in red depicts the Partial View, it has 2 buttons, one to commit the table data into the database while the other is to add more records if needed;

Partial view in Parent View screenshot

My challenge is: I have a class method that needs to get a CSV file from FileUpload value and binds data to the model on the partial view.

See my model structure below:

[Table("atm")]
public class ATM
{
    public ATM()
    {
        this._EJTransactions = new HashSet<EJTransaction>();
        this._CassetteSettings = new HashSet<CassetteSetting>();
        this._EJFileDownloads = new HashSet<EJFileDownload>();
        this._CamFileDownloads = new HashSet<ImageFileDownload>();
        this._TransImages = new HashSet<TransImage>();
        this._UserAtms = new HashSet<UserAtms>();
    }

    [Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int atmId { get; set; }
    [ForeignKey("ATMVendor")]
    public int vendorId { get; set; }
    [ForeignKey("BankBranch")]
    public int branchId { get; set; }
    [MaxLength(50)]
    [Index("ix_uniq_terminal", 1, IsUnique = true)]
    [DisplayName("Terminal ID")]
    public string terminalId { get; set; }
    [MaxLength(30)]
    [Index("ix_uniq_ip", 1, IsUnique = true)]
    [DisplayName("IP")]
    public string ip { get; set; }
    [MaxLength(100)]
    [Index("ix_uniq_title", 1, IsUnique = true)]
    [DisplayName("Title")]
    public string title { get; set; }
    [DisplayName("EJ Enabled")]
    public bool ejEnabled { get; set; }
    [DisplayName("Image Enabled")]
    public bool camEnabled { get; set; }
    [DisplayName("IsActive")]
    public bool isActive { get; set; }

    public virtual ATMVendor ATMVendor { get; set; }
    public virtual BankBranch BankBranch { get; set; }

    public virtual ICollection<EJTransaction> _EJTransactions { get; set; }
    public virtual ICollection<CassetteSetting> _CassetteSettings { get; set; }
    public virtual ICollection<EJFileDownload> _EJFileDownloads { get; set; }
    public virtual ICollection<ImageFileDownload> _CamFileDownloads { get; set; }
    public virtual ICollection<TransImage> _TransImages { get; set; }
    public virtual ICollection<UserAtms> _UserAtms { get; set; }
}

The partial view binds to this model.

public class CSVAtmLoader
{
    public IEnumerable<ATM> Read(string csvfile)
    {
        List<ATM> atmlist = new List<ATM>();
        TextReader csvReader = new StreamReader(csvfile);
        var csv = new CsvReader(csvReader, false);

        csv.Configuration.DetectColumnCountChanges = true;
        csv.Configuration.RegisterClassMap<AtmMap>();

        //csv.Configuration.InjectionCharacters = new[] { '=', '@', '+', '-' };
        //csv.Configuration.SanitizeForInjection = false;
        //csv.Configuration.InjectionEscapeCharacter = '\t';

        var atms = csv.GetRecords<ATM>();
        foreach (var atm in atms)
        {
            atm.branchId = GetBranchId(atm.BankBranch.branch);
            atm.vendorId = GetVendorId(atm.ATMVendor.vendor);
            atmlist.Add(atm);
        }
        return atmlist;
    }

    private int GetBranchId(string branch)
    {
        BankBranch br = new BankBranch { branch = branch }.SelectBranch();
        return 0;
    }

    private int GetVendorId(string vendor)
    {
        return 0;
    }
}

In the parent view, I have a CSVAtm tab that hosts the partial view, I am headway blocked to get this done with dynamism of the layout. See my parent view that render the partial view with csvfile chosen from FileUpload control:

<div class="tab-pane fade" id="csvAtm">
     <p>
        <div class="form-inline">
           <table>
              <tr>
                <td><span> Choose a File:</span>&nbsp;&nbsp;</td>
                <td><input id="csvfile" type="file" name="file" class="btn btn-default" onchange="clear();"/></td>
                <td>&nbsp;&nbsp;</td>
                <td>
                   <input class="btn btn-default col-mid-2" type="button" id="upload" value="Upload" onclick="uploadfile();" />
                </td>
            </tr>
        </table>
     </div>
     <div id="error"></div>
     <br />
     <div class="form-group">

       @{
          if (string.IsNullOrEmpty(filename))
          {
            //this is where my challenge is, how to get the filename from fileupload 
            //I know this is executed at the server side and hence, the client is not aware of server side scripting 
            Html.RenderPartial("LoadedAtms", new CSVAtmLoader().Read(filename));
          }
       }
 </div>

I need a better way to achieve this with fileupload security in mind, my approach might be wrong. If I can achieve this successfully in the csv tab, it will be easier to replicate same for connecting to Sql server.

Thanks so much..