isa: Allow ISA-style drivers on modern systems

Several modern devices, such as PC/104 cards, are expected to run on
modern systems via an ISA bus interface. Since ISA is a legacy interface
for most modern architectures, ISA support should remain disabled in
general. Support for ISA-style drivers should be enabled on a per driver
basis.

To allow ISA-style drivers on modern systems, this patch introduces the
ISA_BUS_API and ISA_BUS Kconfig options. The ISA bus driver will now
build conditionally on the ISA_BUS_API Kconfig option, which defaults to
the legacy ISA Kconfig option. The ISA_BUS Kconfig option allows the
ISA_BUS_API Kconfig option to be selected on architectures which do not
enable ISA (e.g. X86_64).

The ISA_BUS Kconfig option is currently only implemented for X86
architectures. Other architectures may have their own ISA_BUS Kconfig
options added as required.

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
William Breathitt Gray 2016-05-27 18:08:27 -04:00 committed by Greg Kroah-Hartman
parent 7e1b1fc4da
commit 3a4955111a
4 changed files with 14 additions and 2 deletions

View File

@ -606,6 +606,9 @@ config HAVE_ARCH_HASH
file which provides platform-specific implementations of some
functions in <linux/hash.h> or fs/namei.c.
config ISA_BUS_API
def_bool ISA
#
# ABI hall of shame
#

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@ -2439,6 +2439,15 @@ config PCI_CNB20LE_QUIRK
source "drivers/pci/Kconfig"
config ISA_BUS
bool "ISA-style bus support on modern systems" if EXPERT
select ISA_BUS_API
help
Enables ISA-style drivers on modern systems. This is necessary to
support PC/104 devices on X86_64 platforms.
If unsure, say N.
# x86_64 have no ISA slots, but can have ISA-style DMA.
config ISA_DMA_API
bool "ISA-style DMA support" if (X86_64 && EXPERT)

View File

@ -10,7 +10,7 @@ obj-$(CONFIG_DMA_CMA) += dma-contiguous.o
obj-y += power/
obj-$(CONFIG_HAS_DMA) += dma-mapping.o
obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += dma-coherent.o
obj-$(CONFIG_ISA) += isa.o
obj-$(CONFIG_ISA_BUS_API) += isa.o
obj-$(CONFIG_FW_LOADER) += firmware_class.o
obj-$(CONFIG_NUMA) += node.o
obj-$(CONFIG_MEMORY_HOTPLUG_SPARSE) += memory.o

View File

@ -22,7 +22,7 @@ struct isa_driver {
#define to_isa_driver(x) container_of((x), struct isa_driver, driver)
#ifdef CONFIG_ISA
#ifdef CONFIG_ISA_BUS_API
int isa_register_driver(struct isa_driver *, unsigned int);
void isa_unregister_driver(struct isa_driver *);
#else