[PATCH 02/11] drm/sun4i: Fix tcon channel 0 comment about backporch = backporch + hsync

Chen-Yu Tsai wens at csie.org
Thu Mar 9 02:05:25 PST 2017


The backporch programmed into the tcon registers is actually the
backporch + hsync length from the display timings, as indicated in
the interface timing diagrams found in the user manual of the A31
and A33 SoCs.

The comments for channel 0 mistakenly describe the discrepancy as
TCON backporch = frontporch + hsync.

Signed-off-by: Chen-Yu Tsai <wens at csie.org>
---
 drivers/gpu/drm/sun4i/sun4i_tcon.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index ee51d7e77a6a..c52c482c8fd0 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -143,7 +143,7 @@ void sun4i_tcon0_mode_set(struct sun4i_tcon *tcon,
 
 	/*
 	 * This is called a backporch in the register documentation,
-	 * but it really is the front porch + hsync
+	 * but it really is the back porch + hsync
 	 */
 	bp = mode->crtc_htotal - mode->crtc_hsync_start;
 	DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
@@ -156,7 +156,7 @@ void sun4i_tcon0_mode_set(struct sun4i_tcon *tcon,
 
 	/*
 	 * This is called a backporch in the register documentation,
-	 * but it really is the front porch + hsync
+	 * but it really is the back porch + hsync
 	 */
 	bp = mode->crtc_vtotal - mode->crtc_vsync_start;
 	DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
-- 
2.11.0




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