Legal Question in Criminal Law in California

That depends. Selling salt is legal if you tell the buyer it's salt. It's illegal if you tell the buyer it's a drug. What did you say it was? How much did you sell? How much did you have on you and/or elsewhere? Did you know it was just salt at the time, or did you believe it was an illegal substance? Without this information I can't give you a meaningful answer.

Whatever prison time is specified as penalty for the specific charge for your felony sales of drugs, or whatever your attorney can negotiate in a plea bargain. The actual substance doesn't matter, as long as it was represented 'as' drugs.