[Linux-kernel-mentees] [RFC PATCH 00/35] Move all PCIBIOS* definitions into arch/x86

David Laight David.Laight at ACULAB.COM
Wed Jul 15 14:24:21 UTC 2020

From: Arnd Bergmann
> Sent: 15 July 2020 07:47
> On Wed, Jul 15, 2020 at 1:46 AM Bjorn Helgaas <helgaas at kernel.org> wrote:
>  So something like:
> >
> >   void pci_read_config_word(struct pci_dev *dev, int where, u16 *val)
> >
> > and where we used to return anything non-zero, we just set *val = ~0
> > instead?  I think we do that already in most, maybe all, cases.
> Right, this is what I had in mind. If we start by removing the handling
> of the return code in all files that clearly don't need it, looking at
> whatever remains will give a much better idea of what a good interface
> should be.

It would be best to get rid of that nasty 'u16 *' parameter.
Make the return int and return the read value or -1 on error.
(Or maybe 0xffff0000 on error??)

For a 32bit read (there must be one for the BARs) returning
a 64bit signed integer would work even for 32bit systems.

If code cares about the error, and it can be detected then
it can check. Otherwise the it all 'just works'.


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