Calculating the supply function of a generic perfect complements technology

The production function is: Y= min{aL, bK}
I found the demands to be L*= Y/a and K*=Y/b
The cost (prices r for K and w for L) is:
C(K,L) = rY/b + wY/a = Y(r/b + w/a)
The profits thus would be:
profits = pY – C(Y) where p is price of Y
profits = pY – Y(r/b – w/a)
So at the optimum (the First Order Condition)
p = (r/b + w/a)
Now how do I find the amount that this firm would supply? It is a perfectly competitive market and all other firms have the same technology.