I get the following error messages when trying to use si2157.ko in linux 5.17: si2157 13-0060: found a 'Silicon Labs Si2157-A30 ROM 0x50' si2157 13-0060: Can't continue without a firmware I did work in linux 5.16.16 without a firmware file. Unfortunately the driver does not tell me the name of the missing firmware file.
Experienced the same issue, for me firmware file it was looking for was "dvb-tuner-si2157-a30-01.fw". It might be fixed by (haven't checked though): https://lore.kernel.org/linux-media/6f84b7f4-3ede-ae55-e99b-a9d4108c80e2@gmail.com/
It's supposed to be fixed by: https://lore.kernel.org/linux-media/trinity-6009a608-b0ff-4e1a-9b91-ba4a97f10324-1648057812747@3c-app-gmx-bs71/T/#t