radeonfb: Disable new color expand acceleration unless explicitely enabled

This new color expansion acceleration for radeonfb appears to trigger
problems with X on VT switch and suspend/resume on some machines. It
might be a problem in the VT layer or in X, but I haven't quite found
it yet, so in the meantime, this disables the acceleration by default,
reverting to 2.6.27 state. It can be enabled using the "accel_cexp"
module parameter or fbdev argument.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/video/aty/radeon_accel.c b/drivers/video/aty/radeon_accel.c
index a547e5d4c8bf..8da5e5ab8547 100644
--- a/drivers/video/aty/radeon_accel.c
+++ b/drivers/video/aty/radeon_accel.c
@@ -256,7 +256,8 @@ void radeonfb_imageblit(struct fb_info *info, const struct fb_image *image)
                 return;
 
         /* We only do 1 bpp color expansion for now */
-        if (info->flags & FBINFO_HWACCEL_DISABLED || image->depth != 1)
+        if (!accel_cexp ||
+            (info->flags & FBINFO_HWACCEL_DISABLED) || image->depth != 1)
                 goto fallback;
 
         /* Fallback if running out of the screen. We may do clipping