drm/mgag200: Fix framebuffer pitch calculation

The framebuffer pitch calculation needs to be done differently for bpp == 24
- check xf86-video-mga for reference.

Signed-off-by: Egbert Eich <eich@suse.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>

diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
index 020a623..c8983f9 100644 (file)
--- a/drivers/gpu/drm/mgag200/mgag200_mode.c
+++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
@@ -877,7 +877,7 @@ static int mga_crtc_mode_set(struct drm_crtc *crtc,
 
        pitch = crtc->fb->pitches[0] / (crtc->fb->bits_per_pixel / 8);
        if (crtc->fb->bits_per_pixel == 24)
-               pitch = pitch >> (4 - bppshift);
+               pitch = (pitch * 3) >> (4 - bppshift);
        else
                pitch = pitch >> (4 - bppshift);