[PATCH] add Big Endian variants of ioread/iowrite

In the new io infrastructure, all of our operators are expecting the
underlying device to be little endian (because the PCI bus, their main
consumer, is LE).

However, there are a fair few devices and busses in the world that are
actually Big Endian.  There's even evidence that some of these BE bus and
chip types are attached to LE systems.  Thus, there's a need for a BE
equivalent of our io{read,write}{16,32} operations.

The attached patch adds this as io{read,write}{16,32}be.  When it's in,
I'll add the first consume (the 53c700 SCSI chip driver).

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 20 insertions, 0 deletions

diff --git a/lib/iomap.c b/lib/iomap.c
index 5e74390852b0..55689c5d3379 100644
--- a/lib/iomap.c
+++ b/lib/iomap.c
@@ -58,13 +58,23 @@ unsigned int fastcall ioread16(void __iomem *addr)
 {
         IO_COND(addr, return inw(port), return readw(addr));
 }
+unsigned int fastcall ioread16be(void __iomem *addr)
+{
+        IO_COND(addr, return inw(port), return be16_to_cpu(__raw_readw(addr)));
+}
 unsigned int fastcall ioread32(void __iomem *addr)
 {
         IO_COND(addr, return inl(port), return readl(addr));
 }
+unsigned int fastcall ioread32be(void __iomem *addr)
+{
+        IO_COND(addr, return inl(port), return be32_to_cpu(__raw_readl(addr)));
+}
 EXPORT_SYMBOL(ioread8);
 EXPORT_SYMBOL(ioread16);
+EXPORT_SYMBOL(ioread16be);
 EXPORT_SYMBOL(ioread32);
+EXPORT_SYMBOL(ioread32be);
 
 void fastcall iowrite8(u8 val, void __iomem *addr)
 {
@@ -74,13 +84,23 @@ void fastcall iowrite16(u16 val, void __iomem *addr)
 {
         IO_COND(addr, outw(val,port), writew(val, addr));
 }
+void fastcall iowrite16be(u16 val, void __iomem *addr)
+{
+        IO_COND(addr, outw(val,port), __raw_writew(cpu_to_be16(val), addr));
+}
 void fastcall iowrite32(u32 val, void __iomem *addr)
 {
         IO_COND(addr, outl(val,port), writel(val, addr));
 }
+void fastcall iowrite32be(u32 val, void __iomem *addr)
+{
+        IO_COND(addr, outl(val,port), __raw_writel(cpu_to_be32(val), addr));
+}
 EXPORT_SYMBOL(iowrite8);
 EXPORT_SYMBOL(iowrite16);
+EXPORT_SYMBOL(iowrite16be);
 EXPORT_SYMBOL(iowrite32);
+EXPORT_SYMBOL(iowrite32be);
 
 /*
  * These are the "repeat MMIO read/write" functions.