Without auto-bright/auto-maximum, scaling scales (theoretical) maximum to 2^16-1.
This is somewhat tricky, for example for 14-bit canons maximum assumed 16383-black_value, while in reality data maximum is lower (as low as ~12000 for 5D Mark II at intermediate ISOs), that's why maximum adjustment was introduced (there is no way to determine real maximum value from metadata for these camera(s)).
For most other vendors, maximum is not that tricky.
Without auto-bright/auto-maximum, scaling scales (theoretical) maximum to 2^16-1.
This is somewhat tricky, for example for 14-bit canons maximum assumed 16383-black_value, while in reality data maximum is lower (as low as ~12000 for 5D Mark II at intermediate ISOs), that's why maximum adjustment was introduced (there is no way to determine real maximum value from metadata for these camera(s)).
For most other vendors, maximum is not that tricky.