Passport return time for Chennai

[pravincd]

Hi all,
I was wondering if somebody could tell me how long does it take for an applicant to receive the passport back during a visa application? I am applying for a H4 visa for my spouse at Chennai and would like to get a sense on the number of days it would take for them to mail back the passport. We live in Mangalore, Karnataka. Would it be better if we provided a Chennai address? or is there a way to speed things?

Thanks
Pravin