Resize Partition with parted
If you ever wanted to resize a partition to grow unfilled space, you can use parted to grow the partition size.
parted /dev/sdx
or
parted /dev/mmcblk0
Now note the size of the disk and the start of the partition that you want to resize.
rm
Partition Type ? primary/extended ? primary Filesystem type? [ext2]? ext4 start ? startSizeMb/GB End? endSizeMb/GB quit reboot (may not be necessary) resize2fs /dev/sdx