Scott Weiland" Cocaine, Sleeping Pills & Viagra On Tour Bus

Scott Weiland's tour bus was a pharmacy on wheels ... police found a stash of drugs on board that ran the gamut from hardcore narcotics to prescriptions to ED meds.

TMZ obtained a copy of the search warrant Bloomington, MN cops got to search Weiland's bus after his death -- and it shows they found at least 2 bags of a white substance. They've already said that substance tested positive for cocaine.

Also on the bus -- a generic version of Xanax, 2 different brands of sleeping pills, Buprenorphine ... a synthetic opiate painkiller, and Viagra. There was also Ziprasidone ... which is used to treat bipolar disorder and schizophrenia. Scott was diagnosed as bipolar in 2001.

According to the docs, all of those drugs were found in a bedroom on the bus. We know Scott's body was found in a bedroom ... although the document does not mention his name.

Cops also found one bag of a green, leafy substance.