comedi: 8255: Add some I/O base address sanity checks

The "8255" driver allows a COMEDI device to be constructed from one or
more 8255 chips, each at an I/O port base address specified by the
admin-supplied configuration options (`it->options[]`).  Currently, the
driver allows any I/O base addresses to be specified as long as the I/O
regions can be reserved, and it converts the specified `int` option
values holding the base address to `unsigned long`.

It doesn't make sense to allow base addresses that are not aligned to
4-byte boundaries because the hardware register addresses would not be
decoded properly, so add a check for valid alignment.

Convert the option values that specify the base addresses from `int` to
`unsigned int` instead of `unsigned long` so they end up the same on
32-bit and 64-bit systems.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260130170416.49994-3-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

0 files changed, 0 insertions, 0 deletions