Re: [RFC v2 25/39] pcmcia: add HAS_IOPORT dependencies

[Bjorn Helgaas]

On Fri, Apr 29, 2022 at 03:50:41PM +0200, Niklas Schnelle wrote:
> In a future patch HAS_IOPORT=n will result in inb()/outb() and friends
> not being declared. PCMCIA devices are either LEGACY_PCI devices
> which implies HAS_IOPORT or require HAS_IOPORT.
> 
> Acked-by: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
> Co-developed-by: Arnd Bergmann <arnd@xxxxxxxxxx>
> Signed-off-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx>
> ---
>  drivers/pcmcia/Kconfig | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/pcmcia/Kconfig b/drivers/pcmcia/Kconfig
> index 2ce261cfff8e..32b5cd324c58 100644
> --- a/drivers/pcmcia/Kconfig
> +++ b/drivers/pcmcia/Kconfig
> @@ -5,7 +5,7 @@
>  
>  menuconfig PCCARD
>  	tristate "PCCard (PCMCIA/CardBus) support"
> -	depends on !UML
> +	depends on HAS_IOPORT

I don't know much about PC Card.  Is there a requirement that these
devices must use I/O port space?  If so, can you include a spec
reference in the commit log?

I do see the PC Card spec, r8.1, sec 5.5.4.2.2 says:

  All CardBus PC Card adapters must support either memory-mapped I/O
  or both memory-mapped I/O and I/O space. The selection will depend
  largely on the system architecture the adapter is intended to be
  used in. The requirement to also support memory-mapped I/O, if I/O
  space is supported, is driven by the potential emergence of
  memory-mapped I/O only cards. Supporting both modes may also
  position the adapter to be sold into multiple system architectures.

which sounds like I/O space is optional.

>  	help
>  	  Say Y here if you want to attach PCMCIA- or PC-cards to your Linux
>  	  computer.  These are credit-card size devices such as network cards,
> -- 
> 2.32.0
>