drivers/video/ssd1307fb.c: fix bit order bug in the byte translation function

This was leading to a strange behaviour when using the fbcon driver on
top of this one: the letters were in the right order, but each letter
had a vertical symmetry.

This was because the addressing was right for the byte, but the
addressing of each individual bit was inverted.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Brian Lilly <brian@crystalfontz.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Thomas Petazzoni <thomas@free-electrons.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/video/ssd1307fb.c b/drivers/video/ssd1307fb.c
index 4d99dd7a6831f4be0e866bcc552f62225faa526e..395cb6a8d8f3a86e3507be05686218ebee6f7d6f 100644 (file)
--- a/drivers/video/ssd1307fb.c
+++ b/drivers/video/ssd1307fb.c
@@ -145,8 +145,8 @@ static void ssd1307fb_update_display(struct ssd1307fb_par *par)
                                u32 page_length = SSD1307FB_WIDTH * i;
                                u32 index = page_length + (SSD1307FB_WIDTH * k + j) / 8;
                                u8 byte = *(vmem + index);
-                               u8 bit = byte & (1 << (7 - (j % 8)));
-                               bit = bit >> (7 - (j % 8));
+                               u8 bit = byte & (1 << (j % 8));
+                               bit = bit >> (j % 8);
                                buf |= bit << k;
                        }
                        ssd1307fb_write_data(par->client, buf);