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From 175258fc1932255e79b32b369c10634f59c60d10 Mon Sep 17 00:00:00 2001
From: Rex-BC Chen <rex-bc.chen@mediatek.com>
Date: Wed, 9 Mar 2022 15:36:35 +0800
Subject: drm/dsi: transfer DSI HS packets ending at the same time
Git-commit: 1498915233dde830061e008ad639b482fd76f93d
Patch-mainline: v5.19-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

Since a HS transmission is composed of an arbitrary number
of bytes that may not be an integer multiple of lanes, some
lanes may run out of data before others.
(Defined in 6.1.3 of mipi_DSI_specification_v.01-02-00)

However, for some DSI RX devices (for example, anx7625),
there is a limitation that packet number should be the same
on all DSI lanes. In other words, they need to end a HS at
the same time.

Because this limitation is for some specific DSI RX devices,
it is more reasonable to put the enable control in these
DSI RX drivers. If DSI TX driver knows the information,
they can adjust the setting for this situation.

Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Acked-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220309073637.3591-2-rex-bc.chen@mediatek.com
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 include/drm/drm_mipi_dsi.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h
index 147e51b6d241..51e09a1a106a 100644
--- a/include/drm/drm_mipi_dsi.h
+++ b/include/drm/drm_mipi_dsi.h
@@ -137,6 +137,8 @@ struct mipi_dsi_host *of_find_mipi_dsi_host_by_node(struct device_node *node);
 #define MIPI_DSI_CLOCK_NON_CONTINUOUS	BIT(10)
 /* transmit data in low power */
 #define MIPI_DSI_MODE_LPM		BIT(11)
+/* transmit data ending at the same time for all lanes within one hsync */
+#define MIPI_DSI_HS_PKT_END_ALIGNED	BIT(12)
 
 enum mipi_dsi_pixel_format {
 	MIPI_DSI_FMT_RGB888,
-- 
2.38.1