[patch 19/26] fbcon: Fix big-endian bogosity in slow_imageblit()

From: gregkh
Date: Tue Apr 04 2006 - 20:07:04 EST


The monochrome->color expansion routine that handles bitmaps which have
(widths % 8) != 0 (slow_imageblit) produces corrupt characters in big-endian.
This is caused by a bogus bit test in slow_imageblit().

Fix.

Signed-off-by: Antonino Daplas <adaplas@xxxxxxx>
Acked-by: Herbert Poetzl <herbert@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
drivers/video/cfbimgblt.c | 2 +-
include/linux/fb.h | 2 --
2 files changed, 1 insertion(+), 3 deletions(-)

--- linux-2.6.16.1.orig/drivers/video/cfbimgblt.c
+++ linux-2.6.16.1/drivers/video/cfbimgblt.c
@@ -169,7 +169,7 @@ static inline void slow_imageblit(const

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

/* Did the bitshift spill bits to the next long? */
--- linux-2.6.16.1.orig/include/linux/fb.h
+++ linux-2.6.16.1/include/linux/fb.h
@@ -839,12 +839,10 @@ struct fb_info {
#define FB_LEFT_POS(bpp) (32 - bpp)
#define FB_SHIFT_HIGH(val, bits) ((val) >> (bits))
#define FB_SHIFT_LOW(val, bits) ((val) << (bits))
-#define FB_BIT_NR(b) (7 - (b))
#else
#define FB_LEFT_POS(bpp) (0)
#define FB_SHIFT_HIGH(val, bits) ((val) << (bits))
#define FB_SHIFT_LOW(val, bits) ((val) >> (bits))
-#define FB_BIT_NR(b) (b)
#endif

/*

--
-
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