while configuring innotop on my linux (gentoo) host

Typical DSN strings look like
The db and port are optional and can usually be omitted.
If you specify 'mysql_read_default_group=mysql' many options can be read
from your mysql options files (~/.my.cnf, /etc/my.cnf).

Enter a DSN string:host=localhost

I am stuck with this step when i give host=localhost above, I get

"MySQL INNODB_STATUS: Can't connect to data source 'localhost' because I can't work out what driver to use (it doesn't seem to contain a 'dbi:driver:' prefix and the DBI_DRIVER env var is not set) at /usr/bin/innotop line 5409"

Am i missing something

Thanks and Regards