Normally with a B permit you are taxed at the source at a flat rate, no deductions.
If you make more than a certain threshold (120 or 130K Swissies) you get to file a tax declaration.
When you file that tax declaration, you can claim whatever work-related expenses they allow you and whatever you deem suitable.
I did claim all moving expenses US > CH incl. hotel, rental car, flights, etc. and so far the authorities haven't objected. Then again, they haven't paid me back the taxes I think they owe me either. We shall see.
The
Steueramt Kanton Bern might have the info you need (but not the language you are looking for).