If I remember correctly, Jpegs can only store 8 bits for colour data. 32 bits is for HDR and in most cameras, the sensor is unable to store that wide a dynamic range of data, hence it's normally 12 bits up-convert to 16 bits.
I don't see much point in converting 16 bit photos to 32 bit photos since you don't really gain much, and need more processing power / memory when editing the photos. If anyone knows what advantages it might bring (for non HDR purposes) please correct me.
Why do you want to convert your RAW files to 32 bits? Unless you are merging multiple exposures for a HDR image, in which Photoshop automates the process and outputs a 32 bit photo for editing.