On Fri, Jan 07, 2022 at 05:28:59PM +0800, David Laight wrote:

That !!alt_base doesn't look right. Without looking at the rest of the code maybe: if (!base && !alt_base) may be correct.

Thanks, that's my fault. I will correct it.

It also rather makes me wonder about the actual failure return value. If devm_ioport_map() returns a 'port number' for inb()/outb() then zero is technically a valid value!

That's not right. The devm_ioport_map() returns NULL if fails and returns non-NULL pointer if success. And also we can find in `drivers/ata/pata_platform.c` that it also use the same way to check the return value from devm_ioport_map().

I will submit a new version to correct my code.

Sincerely thanks, Jiang