[ARM] Refine selection of ISA_DMA_API and generic dma.c code

ISA_DMA_API tells the rest of the kernel if the ISA DMA API is
available.  Select this symbol only on machine types which make
use of the ISA DMA API.

Make building of arch/arm/kernel/dma.c depend on this symbol -
if a machine does not support the ISA DMA API, it's pointless
building this file.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

2 files changed, 7 insertions, 2 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 4b15f5f1e254..cb413109da0c 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -154,6 +154,7 @@ config ARCH_RPC
         select FIQ
         select TIMER_ACORN
         select ARCH_MAY_HAVE_PC_FDC
+        select ISA_DMA_API
         help
           On the Acorn Risc-PC, Linux can support the internal IDE disk and
           CD-ROM interface, serial and parallel port, and the floppy drive.
@@ -206,6 +207,7 @@ config ARCH_IMX
 
 config ARCH_H720X
         bool "Hynix-HMS720x-based"
+        select ISA_DMA_API
         help
           This enables support for systems based on the Hynix HMS720x
 
@@ -290,12 +292,14 @@ 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.
 
+# Select ISA DMA controller support
 config ISA_DMA
         bool
+        select ISA_DMA_API
 
+# Select ISA DMA interface
 config ISA_DMA_API
         bool
-        default y
 
 config PCI
         bool "PCI support" if ARCH_INTEGRATOR_AP || ARCH_VERSATILE_PB
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 25b14c3fdc4a..de94b0f3ee2a 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -6,11 +6,12 @@ AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET)
 
 # Object file lists.
 
-obj-y           := compat.o dma.o entry-armv.o entry-common.o irq.o \
+obj-y           := compat.o entry-armv.o entry-common.o irq.o \
                    process.o ptrace.o semaphore.o setup.o signal.o sys_arm.o \
                    time.o traps.o
 
 obj-$(CONFIG_APM)               += apm.o
+obj-$(CONFIG_ISA_DMA_API)       += dma.o
 obj-$(CONFIG_ARCH_ACORN)        += ecard.o 
 obj-$(CONFIG_FOOTBRIDGE)        += isa.o
 obj-$(CONFIG_FIQ)               += fiq.o