[PATCH 11/15] drm/sun4i: tcon: Fix tcon channel 1 backporch calculation

Maxime Ripard maxime.ripard at free-electrons.com
Tue Mar 7 00:56:30 PST 2017


It seems like what's called a backporch in the datasheet is actually the
backporch plus the sync period. Fix that in our driver.

Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
---
 drivers/gpu/drm/sun4i/sun4i_tcon.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index 93249c5ab1e4..e44217fb4f6f 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -240,15 +240,14 @@ void sun4i_tcon1_mode_set(struct sun4i_tcon *tcon, struct drm_encoder *encoder,
 		     SUN4I_TCON1_BASIC2_Y(mode->crtc_vdisplay));
 
 	/* Set horizontal display timings */
-	bp = mode->crtc_htotal - mode->crtc_hsync_end;
+	bp = mode->crtc_htotal - mode->crtc_hsync_start;
 	DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
 			 mode->htotal, bp);
 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC3_REG,
 		     SUN4I_TCON1_BASIC3_H_TOTAL(mode->crtc_htotal) |
 		     SUN4I_TCON1_BASIC3_H_BACKPORCH(bp));
 
-	/* Set vertical display timings */
-	bp = mode->crtc_vtotal - mode->crtc_vsync_end;
+	bp = mode->crtc_vtotal - mode->crtc_vsync_start;
 	DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
 			 mode->vtotal, bp);
 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC4_REG,
-- 
git-series 0.8.11



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