Consolidate the swab macros into one location

Signed-off-by: Josh Boyer <jwboyer@gmail.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/include/mtd_swab.h b/include/mtd_swab.h
new file mode 100644
index 0000000..05732a9
--- /dev/null
+++ b/include/mtd_swab.h
@@ -0,0 +1,33 @@
+#ifndef MTD_SWAB_H
+#define MTD_SWAB_H
+
+#include <endian.h>
+
+#define swab16(x) \
+        ((__u16)( \
+                (((__u16)(x) & (__u16)0x00ffU) << 8) | \
+                (((__u16)(x) & (__u16)0xff00U) >> 8) ))
+#define swab32(x) \
+        ((__u32)( \
+                (((__u32)(x) & (__u32)0x000000ffUL) << 24) | \
+                (((__u32)(x) & (__u32)0x0000ff00UL) <<  8) | \
+                (((__u32)(x) & (__u32)0x00ff0000UL) >>  8) | \
+                (((__u32)(x) & (__u32)0xff000000UL) >> 24) ))
+
+#if __BYTE_ORDER == __BIG_ENDIAN
+#define cpu_to_le16(x) ({ __u16 _x = x; swab16(_x); })
+#define cpu_to_le32(x) ({ __u32 _x = x; swab32(_x); })
+#define cpu_to_be16(x) (x)
+#define cpu_to_be32(x) (x)
+#else
+#define cpu_to_le16(x) (x)
+#define cpu_to_le32(x) (x)
+#define cpu_to_be16(x) ({ __u16 _x = x; swab16(_x); })
+#define cpu_to_be32(x) ({ __u32 _x = x; swab32(_x); })
+#endif
+#define le16_to_cpu(x) cpu_to_le16(x)
+#define be16_to_cpu(x) cpu_to_be16(x)
+#define le32_to_cpu(x) cpu_to_le32(x)
+#define be32_to_cpu(x) cpu_to_be32(x)
+
+#endif