Is there any way to retain a secondary partition to older form?

I have a SD Card of 4GB. Me Partitioned it using Link2sd.I made an ext2 partition of 2GB for using it as Internel Memmory.Now the SD Card size is shown as 2GB(when put it into computer).Can I retain the partitioned space to older form and can I use the SD Card as a 4GB memmory SD Card?