PCI: Add pci_remap_iospace() to map bus I/O resources

Add pci_remap_iospace() to map bus I/O resources into the CPU virtual
address space.  Architectures with special needs may provide their own
version, but most should be able to use this one.

This function is useful for PCI host bridge drivers that need to map the
PCI I/O resources into virtual memory space.

[bhelgaas: phys_addr description, drop temporary "err" variable]
Signed-off-by: Liviu Dudau <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Rob Herring <[email protected]>
Reviewed-by: Catalin Marinas <[email protected]>
CC: Arnd Bergmann <[email protected]>
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index 53b2acc..977e545 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -249,6 +249,10 @@
 #define pgprot_writecombine pgprot_noncached
 #endif
 
+#ifndef pgprot_device
+#define pgprot_device pgprot_noncached
+#endif
+
 /*
  * When walking page tables, get the address of the next boundary,
  * or the end address of the range if that comes earlier.  Although no