powerpc: Enable /dev/port when isa_io_special is set
isa_io_special is set when the platform provides a "special"
implementation of inX/outX via some FW interface for example.
Such a platform doesn't need an ISA bridge on PCI, and so /dev/port
should be made available even if one isn't present.
This makes the LPC bus IOs accessible via /dev/port on PowerNV Power8
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h
index db1f296..575fbf8 100644
--- a/arch/powerpc/include/asm/io.h
+++ b/arch/powerpc/include/asm/io.h
@@ -21,7 +21,7 @@
/*
* has legacy ISA devices ?
*/
-#define arch_has_dev_port() (isa_bridge_pcidev != NULL)
+#define arch_has_dev_port() (isa_bridge_pcidev != NULL || isa_io_special)
#endif
#include <linux/device.h>