The ssd132x buffer is encoded one pixel per nibble, with two pixels in
each byte. When encoding an 8-bit greyscale input, take the top 4-bits
as the value and ensure the two pixels are distinct and do not overwrite
each other.
Fixes: fdd591e00a9c ("drm/ssd130x: Add support for the SSD132x OLED controller family")
Signed-off-by: John Keeping <jkeeping@xxxxxxxxxxxxxxxxx>
Reviewed-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>
---
Changes since v1:
- Correct a typo in the commit message
- Add Fixes and Reviewed-by tags (thanks Javier!)
drivers/gpu/drm/solomon/ssd130x.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/solomon/ssd130x.c b/drivers/gpu/drm/solomon/ssd130x.c
index b777690fd6607..4bb663f984ce3 100644
--- a/drivers/gpu/drm/solomon/ssd130x.c
+++ b/drivers/gpu/drm/solomon/ssd130x.c
@@ -880,7 +880,7 @@ static int ssd132x_update_rect(struct ssd130x_device *ssd130x,
u8 n1 = buf[i * width + j];
u8 n2 = buf[i * width + j + 1];
- data_array[array_idx++] = (n2 << 4) | n1;
+ data_array[array_idx++] = (n2 & 0xf0) | (n1 >> 4);
}
}
--
2.48.0
