<dxg:GridControl.Columns>
    <dxg:GridColumn Header="Связь" SortOrder="Descending" FieldName="LinkDto.Id">
        <dxg:GridColumn.DisplayTemplate>
            <ControlTemplate>
                <dxe:ComboBoxEdit MinWidth="120" HorizontalAlignment="Left" VerticalAlignment="Center"
                    ItemsSource="{Binding LinkTypes}, Converter={ StaticResource LinkDtoConvertor }, ConverterParameter={ ??? }}"
                    SelectedItem="{Binding Path=RowData.Row.LinkDto}" DisplayMember="Name" />
            </ControlTemplate>
        </dxg:GridColumn.DisplayTemplate>
    </dxg:GridColumn>
</dxg:GridControl.Columns>

<dxg:GridControl.Columns>
    <dxg:GridColumn Header="Связь" SortOrder="Descending" FieldName="LinkDto.Id">
        <dxg:GridColumn.DisplayTemplate>
            <ControlTemplate>
                <dxe:ComboBoxEdit MinWidth="120" HorizontalAlignment="Left" VerticalAlignment="Center"
                         SelectedItem="{Binding Path=RowData.Row.LinkDto}" DisplayMember="Name">
			<dxe:ComboBoxEdit.ItemsSource>
			      <MultiBinding Converter="{StaticResource LinkDtoConvertor}"> 
				    <Binding Path="RowData.Row.LinkDto" />
			      </MultiBinding>
			</dxe:ComboBoxEdit.ItemsSource>
		 </dxe:ComboBoxEdit>		
            </ControlTemplate>
        </dxg:GridColumn.DisplayTemplate>
    </dxg:GridColumn>
</dxg:GridControl.Columns>

class LinkDtoConvertor : IMultiValueConverter
{
    public object Convert(object[] values, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        if (values != null && values.First() != null)
        {
			var value = values.First() as LinkDto;
			if (value != null)
			{
			    return value.id	== LinkEnum.One 
				    ? getAllLinkDto()
                    : getAllLinkDto().Where(w => w.Id != LinkEnum.One).ToList();					
			}
        }
        return null;
    }

    public object[] ConvertBack(object value, Type[] targetTypes, object parameter, System.Globalization.CultureInfo culture)
    {
        return null; 
    }
}
class LinkDto 
{
    public LinkEnum Id {get; set;}
    public string Name {get; set;}	
}
enum LinkEnum : byte
{
	One = 1,
	Two = 2,
	Three = 3
}

IList<LinkDto> getAllLinkDto();