[PATCH] fbcon: Re-fix little-endian bogosity in slow_imageblit()

From: Franck Bui-Huu
Date: Fri Nov 03 2006 - 09:55:33 EST


From: Franck Bui-Huu <fbuihuu@xxxxxxxxx>

This bug has been introduced by commit:

a536093a2f07007aa572e922752b7491b9ea8ff2

This commit fixed the big-endian case but broke the little-endian one.
This patch revert the previous change and swap the definition of
FB_BIT_NR() macro between big and little endian. It should work for
both endianess now.

Signed-off-by: Franck Bui-Huu <fbuihuu@xxxxxxxxx>
---

This is the most obvious fix for me although it's a bit weird
that bit ordering depend on platform endianess. I don't know
fb code so I prefer submitting this trivial fix rather than
breaking every thing else ;)

drivers/video/cfbimgblt.c | 4 ++--
include/linux/fb.h | 2 ++
2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/video/cfbimgblt.c b/drivers/video/cfbimgblt.c
index 51d3538..8f47bf4 100644
--- a/drivers/video/cfbimgblt.c
+++ b/drivers/video/cfbimgblt.c
@@ -168,7 +168,7 @@ static inline void slow_imageblit(const

while (j--) {
l--;
- color = (*s & (1 << l)) ? fgcolor : bgcolor;
+ color = (*s & (1 << FB_BIT_NR(l))) ? fgcolor : bgcolor;
val |= FB_SHIFT_HIGH(color, shift);

/* Did the bitshift spill bits to the next long? */
@@ -258,7 +258,7 @@ static inline void fast_imageblit(const
s += spitch;
}
}
-
+
void cfb_imageblit(struct fb_info *p, const struct fb_image *image)
{
u32 fgcolor, bgcolor, start_index, bitstart, pitch_index = 0;
diff --git a/include/linux/fb.h b/include/linux/fb.h
index 3e69241..6ca18b8 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -854,10 +854,12 @@ #define fb_memset memset
#endif

#if defined (__BIG_ENDIAN)
+#define FB_BIT_NR(b) (b)
#define FB_LEFT_POS(bpp) (32 - bpp)
#define FB_SHIFT_HIGH(val, bits) ((val) >> (bits))
#define FB_SHIFT_LOW(val, bits) ((val) << (bits))
#else
+#define FB_BIT_NR(b) (7 - (b))
#define FB_LEFT_POS(bpp) (0)
#define FB_SHIFT_HIGH(val, bits) ((val) << (bits))
#define FB_SHIFT_LOW(val, bits) ((val) >> (bits))
--
1.4.3.2

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