Unverified Commit 81fafb94 authored by Icenowy Zheng's avatar Icenowy Zheng Committed by Maxime Ripard
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drm/sun4i: dsi: fix the overhead of the horizontal front porch 



The formula in the BSP kernel indicates that a 16-byte overhead is used
when sending the HFP. However, this value is currently set to 6 in the
sun6i_mipi_dsi driver, which makes some panels flashing.

Fix this overhead value.

Signed-off-by: default avatarIcenowy Zheng <icenowy@aosc.io>
Signed-off-by: default avatarMaxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191006160303.24413-3-icenowy@aosc.io
parent 10d8f308

drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c

+5 −4
Original line number Diff line number Diff line
@@ -569,11 +569,12 @@ static void sun6i_dsi_setup_timings(struct sun6i_dsi *dsi, 
			  (mode->htotal - mode->hsync_end) * Bpp - HBP_PACKET_OVERHEAD);



		/*

		 * The frontporch is set using a blanking packet (4

		 * bytes + payload + 2 bytes). Its minimal size is

		 * therefore 6 bytes

		 * The frontporch is set using a sync event (4 bytes)

		 * and two blanking packets (each one is 4 bytes +

		 * payload + 2 bytes). Its minimal size is therefore

		 * 16 bytes

		 */

#define HFP_PACKET_OVERHEAD	6

#define HFP_PACKET_OVERHEAD	16

		hfp = max((unsigned int)HFP_PACKET_OVERHEAD,

			  (mode->hsync_start - mode->hdisplay) * Bpp - HFP_PACKET_OVERHEAD);

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