SONY doesn't manufacture SOC's so there's nothing there.
Jolla can't develop drivers for something that it does not make also.
RE drivers in commercial products and in mobile bussines is highly unlikely also.
So. libhybris..... because there's no native drivers since non of the SOC manufacturers (Qualcomm, MTK, Samsung, Huawei and now Xiaomi) is going to make one for Sailfish. At least not ATM, we can just hope for brighter future.
Even the non SOC ARM vendors are not exactly known as great for FOSS and linux support.