[PATCH] include/asm-generic/io.h: add dummy fuctions to support 'COMPILE_TEST' in 'asm-generic'.

[Chen Gang <gang.chen@asianux.com>]

'asm-generic' need provide necessary configuration checking, if can't
pass checking, 'asm-generic' shouldn't implement it.

For 'COMPILE_TEST', according to its help contents, 'asm-generic' need
let it pass configuration checking, and provide related dummy contents
for it.

Part of 'COMPLE_TEST' help contents in "init/Kconfig":

  "...Despite they cannot be loaded there (or even when they load they cannot be used due to missing HW support)..."


Signed-off-by: Chen Gang <gang.chen@asianux.com>
---
 include/asm-generic/io.h |   22 ++++++++++++++++++----
 1 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index d5afe96..301ce80 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -303,13 +303,18 @@ static inline void *phys_to_virt(unsigned long address)
 /*
  * Change "struct page" to physical address.
  *
- * This implementation is for the no-MMU case only... if you have an MMU
- * you'll need to provide your own definitions.
+ * This for the no-MMU, or no-IOMEM but still try to COMPILE_TEST cases.
+ * if you have an MMU and IOMEM, you'll need to provide your own definitions.
  */
-#ifndef CONFIG_MMU
+#if !defined(CONFIG_MMU) || \
+	(!defined(CONFIG_HAS_IOMEM) && defined(CONFIG_COMPILE_TEST))
 static inline void __iomem *ioremap(phys_addr_t offset, unsigned long size)
 {
+#if !defined(CONFIG_MMU)
 	return (void __iomem*) (unsigned long)offset;
+#else
+	return NULL;
+#endif
 }
 
 #define __ioremap(offset, size, flags)	ioremap(offset, size)
@@ -325,7 +330,7 @@ static inline void __iomem *ioremap(phys_addr_t offset, unsigned long size)
 static inline void iounmap(void __iomem *addr)
 {
 }
-#endif /* CONFIG_MMU */
+#endif /* !CONFIG_MMU || (!CONFIG_HAS_IOMEM && CONFIG_COMPILE_TEST) */
 
 #ifdef CONFIG_HAS_IOPORT
 #ifndef CONFIG_GENERIC_IOMAP
@@ -341,6 +346,15 @@ static inline void ioport_unmap(void __iomem *p)
 extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
 extern void ioport_unmap(void __iomem *p);
 #endif /* CONFIG_GENERIC_IOMAP */
+#elif defined(CONFIG_COMPILE_TEST) /* CONFIG_HAS_IOPORT */
+static inline void __iomem *ioport_map(unsigned long port, unsigned int nr)
+{
+	return NULL;
+}
+
+static inline void ioport_unmap(void __iomem *p)
+{
+}
 #endif /* CONFIG_HAS_IOPORT */
 
 #ifndef xlate_dev_kmem_ptr
-- 
1.7.7.6