Re: [GIT PULL] Driver core update for 4.7-rc1

[William Breathitt Gray <vilhelm.gray@gmail.com>]

On Sat, May 21, 2016 at 09:59:09AM -0700, Linus Torvalds wrote:
>Author: Linus Torvalds <torvalds@linux-foundation.org>
>Date:   Sat May 21 09:13:41 2016 -0700
>
>    x86 isa: add back X86_32 dependency on CONFIG_ISA
>    
>    Commit b3c1be1b789c ("base: isa: Remove X86_32 dependency") made ISA
>    support available on x86-64 too.  That's not right - while there are
>    some LPC-style devices that might be useful still and be based on
>    ISA-like IP blocks, that is *not* an excuse to try to enable any random
>    legacy drivers.
>    
>    Such drivers should be individually enabled and made to perhaps depend
>    on ISA_DMA_API instead (which we have continued to support on x86-64).
>    Or we could add another "ISA_XYZ_API" that we support that doesn't
>    enable random old drivers that aren't even 64-bit clean nor do we have
>    any test coverage for.
>    
>    Turning off ISA will now also turn off some drivers that have been
>    marked as depending on it as part of this series, and that used to work
>    on modern platforms.
>    
>    See for example commits ad7afc38eab3..cc736607c86d, which may also need
>    to be reverted.
>    
>    Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
>    Cc: Linus Walleij <linus.walleij@linaro.org>
>    Cc: Guenter Roeck <linux@roeck-us.net>
>    Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
>
>diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
>index 48ac29034e1e..0a7b885964ba 100644
>--- a/arch/x86/Kconfig
>+++ b/arch/x86/Kconfig
>@@ -2447,6 +2447,8 @@ config ISA_DMA_API
> 	  Enables ISA-style DMA support for devices requiring such controllers.
> 	  If unsure, say Y.
> 
>+if X86_32
>+
> config ISA
> 	bool "ISA support"
> 	---help---
>@@ -2456,8 +2458,6 @@ config ISA
> 	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
> 	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
> 
>-if X86_32
>-
> config EISA
> 	bool "EISA support"
> 	depends on ISA

Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>

That makes sense to me. The drivers which switched to use the ISA bus
driver would simply need their respective Kconfig option adjusted to
depend on a "ISA_BUS_API" option, rather than ISA, to allow them to
compile on X86_64.

Would you like me to submit a patchset after your commit to introduce
the ISA_BUS/ISA_BUS_API Kconfig options, as well as adjust the relevant
drivers' Kconfig options to depend on the ISA_BUS_API?

William Breathitt Gray