Here an aha1542.c that was last tested in a 2.1.132 kernel.

The old aha1542 has been used by thousands of people
for thousands of hours and is rock solid when no hardware
errors occur. However, when hardware errors occur
(reading a bad CDROM, writing a bad tape, ...)
then the system comes crashing down in an avalanche
of errors, continuously resetting the SCSI bus.
The details differ between old and new scsi_error
handling but the effect is just as catastrophical.

The present aha1542.c may not compile in your kernel, and
if it compiles it may not work. Only a handful of people have
used it. However, so far the impression is that it is
definitely better in some circumstances and never worse
than the old driver.

Please mail experiences to aeb@cwi.nl. Once a sizable number
of people has used it for a significant amount of time
without problems that they didnt have before, I can consider
offering this for inclusion in an official kernel tree.

Andries