fb: add support for foreign endianness

Add support for the framebuffers with non-native endianness.  This is done via
FBINFO_FOREIGN_ENDIAN flag that will be used by the drivers.  Depending on the
host endianness this flag will be overwritten by FBINFO_BE_MATH internal flag,
or cleared.

Tested to work on MPC8360E-RDK (BE) + Fujitsu MINT framebuffer (LE).

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: <Valdis.Kletnieks@vt.edu>
Cc: Clemens Koller <clemens.koller@anagramm.de>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index e3dc8f8d0c3e..da7b9705ca81 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -139,6 +139,30 @@ config FB_SYS_IMAGEBLIT
           blitting. This is used by drivers that don't provide their own
           (accelerated) version and the framebuffer is in system RAM.
 
+menuconfig FB_FOREIGN_ENDIAN
+        bool "Framebuffer foreign endianness support"
+        depends on FB
+        ---help---
+          This menu will let you enable support for the framebuffers with
+          non-native endianness (e.g. Little-Endian framebuffer on a
+          Big-Endian machine). Most probably you don't have such hardware,
+          so it's safe to say "n" here.
+
+choice
+        prompt "Choice endianness support"
+        depends on FB_FOREIGN_ENDIAN
+
+config FB_BOTH_ENDIAN
+        bool "Support for Big- and Little-Endian framebuffers"
+
+config FB_BIG_ENDIAN
+        bool "Support for Big-Endian framebuffers only"
+
+config FB_LITTLE_ENDIAN
+        bool "Support for Little-Endian framebuffers only"
+
+endchoice
+
 config FB_SYS_FOPS
        tristate
        depends on FB