According to Section 20 of the Representation of People Act, 1950, A person is said to be ordinarily resident in a place if he uses that place for sleeping. He does not even have to be eating in that place and may be eating from a place outside.

Even Temporary periods of absence from this " residance" can be ignored. Also it is not necessary that the period of stay should be continuous for any particular length of time and should be without any break. Temporary absence on account of duty or employment or even for vacation is not considered a hurdle to the concept of ordinary residence.

Even for passport if you have your own house but living in a rented place ,the place of residence will be your rented place only because that is where you are living.

This section allows even people living in sheds and persons living on pavements without any roof as eligible for enrolment provided they are ordinarily residing in the sheds or on pavements in a particular area and do not change their place of residing.

Hope this answers your query!