From the command prompt launch fdisk:
# fdisk /dev/mmcblk0
Device Boot Start End Sectors Size Id Type /dev/mmcblk0p1 * 8192 249855 241664 118M c W95 FAT32 (LBA) /dev/mmcblk0p2 249856 15677439 15427584 7.4G 83 Linux
Delete the primary Linux partition with d. The partition number is 2
Create a new primary partition with the command n starting from the same block and ending to the maximum block indicated as default.
Write the table with w then exit with q.
Reboot the board with:
once the system has reboot and you are back at the commandline enter the following command:
# resize2fs /dev/mmcblk0p2 resize2fs 1.42.12 (29-Aug-2014) Filesystem at /dev/mmcblk0p2 is mounted on /; on-line resizing required old_desc_blocks = 1, new_desc_blocks = 1 EXT4-fs (mmcblk0p2): resizing filesystem from 188416 to 1928448 blocks EXT4-fs (mmcblk0p2): resized filesystem to 1928448 The filesystem on /dev/mmcblk0p2 is now 1928448 (4k) blocks long.