[BUG] base: isa: ISA bus functionality not compiled for X86_64 architecture

[BUG] base: isa: ISA bus functionality not compiled for X86_64 architecture

[William Breathitt Gray]

Hello,

I'm developing drivers for devices accessible over a PC/104 bus (a bus
specification derived from ISA). Up until now I've used the
platform_driver structure in my drivers, but I believe it would be more
appropriate to use the isa_driver structure located in the
include/linux/isa.h file.

I discovered that the relevant ISA bus functions located in the
drivers/base/isa.c file are conditionally compiled based on the
CONFIG_ISA option declared in the arch/x86/Kconfig file. Unfortunately,
the CONFIG_ISA option can only be set to Y if the CONFIG_X86_32 option
is set to Y; I'm running a 64-bit X86 processor, so I naturally have
CONFIG_X86_32 set to N.

Would it be proper to remove the CONFIG_X86_32 dependency from the
CONFIG_ISA option? Motherboards with the PC/104 bus are effectively
motherboards with the ISA bus. Alternatively, I can submit a respective
pc104.c and pc104.h patch to implement a PC/104 bus driver, but it would
essentially be a virtually vertabim copy of the ISA bus implementation
(e.g. s/isa/pc104/g).

What are your thoughts?

Sincerely,

William Breathitt Gray

Re: [BUG] base: isa: ISA bus functionality not compiled for X86_64 architecture

[Greg KH]

On Wed, Jan 20, 2016 at 09:00:03AM -0500, William Breathitt Gray wrote:
> Hello,
> 
> I'm developing drivers for devices accessible over a PC/104 bus (a bus
> specification derived from ISA). Up until now I've used the
> platform_driver structure in my drivers, but I believe it would be more
> appropriate to use the isa_driver structure located in the
> include/linux/isa.h file.
> 
> I discovered that the relevant ISA bus functions located in the
> drivers/base/isa.c file are conditionally compiled based on the
> CONFIG_ISA option declared in the arch/x86/Kconfig file. Unfortunately,
> the CONFIG_ISA option can only be set to Y if the CONFIG_X86_32 option
> is set to Y; I'm running a 64-bit X86 processor, so I naturally have
> CONFIG_X86_32 set to N.
> 
> Would it be proper to remove the CONFIG_X86_32 dependency from the
> CONFIG_ISA option? Motherboards with the PC/104 bus are effectively
> motherboards with the ISA bus. Alternatively, I can submit a respective
> pc104.c and pc104.h patch to implement a PC/104 bus driver, but it would
> essentially be a virtually vertabim copy of the ISA bus implementation
> (e.g. s/isa/pc104/g).
> 
> What are your thoughts?

Just allow ISA to be built on x86-64, no one before has told us of
hardware that works on this platform.  Feel free to send in a patch that
makes things work properly for you.

thanks,

greg k-h