[PATCH 4.9 46/84] drm: rcar-du: Fix display timing controller parameter

Greg Kroah-Hartman
2017-08-28T08:12:01Z

From: Koji Matsuoka <koji.matsuoka.xm@renesas.com>

commit 9cdced8a39c04cf798ddb2a27cb5952f7d39f633 upstream.

There is a bug in the setting of the DES (Display Enable Signal)
register. This current setting occurs 1 dot left shift. The DES
register should be set minus one value about the specifying value
with H/W specification. This patch corrects it.

Signed-off-by: Koji Matsuoka <koji.matsuoka.xm@renesas.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Thong Ho <thong.ho.px@rvc.renesas.com>
Signed-off-by: Nhan Nguyen <nhan.nguyen.yb@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
@@ -172,7 +172,7 @@ static void rcar_du_crtc_set_display_tim
mode->crtc_vsync_start - 1);
rcar_du_crtc_write(rcrtc, VCR, mode->crtc_vtotal - 1);

- rcar_du_crtc_write(rcrtc, DESR, mode->htotal - mode->hsync_start);
+ rcar_du_crtc_write(rcrtc, DESR, mode->htotal - mode->hsync_start - 1);
rcar_du_crtc_write(rcrtc, DEWR, mode->hdisplay);
}