From 3c6bd94d32c45d47a0fce49e9cd64d72ff612bb5 Mon Sep 17 00:00:00 2001
From: Jitao Shi <jitao.shi@mediatek.com>
Date: Sun, 11 Aug 2019 18:40:04 +0800
Subject: drm/mediatek: add dsi reg commit disable control
Git-commit: 3c6bd94d32c45d47a0fce49e9cd64d72ff612bb5
Patch-mainline: v5.5-rc1
References: bsc#1152489

New DSI IP has shadow register and working reg. The register
values are writen to shadow register. And then trigger with
commit reg, the register values will be moved working register.

This function is default on. But this driver doesn't use this
function. So add the disable control.

Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
Signed-off-by: CK Hu <ck.hu@mediatek.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/mediatek/mtk_dsi.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
index a7caf75fb971..881c0afabf17 100644
--- a/drivers/gpu/drm/mediatek/mtk_dsi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
@@ -125,6 +125,10 @@
 #define VM_CMD_EN			BIT(0)
 #define TS_VFP_EN			BIT(5)
 
+#define DSI_SHADOW_DEBUG	0x190U
+#define FORCE_COMMIT			BIT(0)
+#define BYPASS_SHADOW			BIT(1)
+
 #define CONFIG				(0xff << 0)
 #define SHORT_PACKET			0
 #define LONG_PACKET			2
@@ -151,6 +155,7 @@ struct phy;
 
 struct mtk_dsi_driver_data {
 	const u32 reg_cmdq_off;
+	bool has_shadow_ctl;
 };
 
 struct mtk_dsi {
@@ -588,6 +593,11 @@ static int mtk_dsi_poweron(struct mtk_dsi *dsi)
 	}
 
 	mtk_dsi_enable(dsi);
+
+	if (dsi->driver_data->has_shadow_ctl)
+		writel(FORCE_COMMIT | BYPASS_SHADOW,
+		       dsi->regs + DSI_SHADOW_DEBUG);
+
 	mtk_dsi_reset_engine(dsi);
 	mtk_dsi_phy_timconfig(dsi);
 
-- 
2.28.0