linux-kernel - [PATCH v3 2/2] drm/mediatek: control panel's power before MIPI LP11

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Message-ID: <20211116094930.11470-3-jitao.shi@mediatek.com>
Date:   Tue, 16 Nov 2021 17:49:30 +0800
From:   Jitao Shi <jitao.shi@...iatek.com>
To:     Thierry Reding <thierry.reding@...il.com>,
        Sam Ravnborg <sam@...nborg.org>,
        David Airlie <airlied@...ux.ie>,
        Daniel Vetter <daniel@...ll.ch>,
        Matthias Brugger <matthias.bgg@...il.com>,
        Chun-Kuang Hu <chunkuang.hu@...nel.org>,
        Philipp Zabel <p.zabel@...gutronix.de>,
        <dri-devel@...ts.freedesktop.org>, <linux-kernel@...r.kernel.org>
CC:     <linux-mediatek@...ts.infradead.org>, <stonea168@....com>,
        <huijuan.xie@...iatek.com>, <shuijing.li@...iatek.com>,
        <liangxu.xu@...iatek.com>, <xinlei.li@...iatek.com>,
        Jitao Shi <jitao.shi@...iatek.com>
Subject: [PATCH v3 2/2] drm/mediatek: control panel's power before MIPI LP11

"auo,kd101n80-45na" requires the panel's IOVDD take precedence over
MIPI DATA. Otherwise there is a risk of leakage.

Signed-off-by: Jitao Shi <jitao.shi@...iatek.com>
Change-Id: I2da6179dea7e15bc5a53fe36db200b6c04f4d551
---
 drivers/gpu/drm/mediatek/mtk_dsi.c | 28 ++++++++++++++++++++++------
 1 file changed, 22 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
index 93b40c245f00..9fff0c483139 100644
--- a/drivers/gpu/drm/mediatek/mtk_dsi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
@@ -24,7 +24,7 @@
 #include <drm/drm_print.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_simple_kms_helper.h>
-
+#include <drm/panel_boe_tv101wum_nl6.h>
 #include "mtk_disp_drv.h"
 #include "mtk_drm_ddp_comp.h"
 
@@ -185,6 +185,7 @@ struct mtk_dsi {
 	struct drm_bridge bridge;
 	struct drm_bridge *next_bridge;
 	struct drm_connector *connector;
+	struct drm_panel *panel;
 	struct phy *phy;
 
 	void __iomem *regs;
@@ -619,10 +620,16 @@ static int mtk_dsi_poweron(struct mtk_dsi *dsi)
 	dsi->data_rate = DIV_ROUND_UP_ULL(dsi->vm.pixelclock * bit_per_pixel,
 					  dsi->lanes);
 
+	if (dsi->panel) {
+		if (panel_prepare_power(dsi->panel)) {
+			DRM_INFO("can't prepare power the panel\n");
+			goto err_refcount;
+		}
+	}
 	ret = clk_set_rate(dsi->hs_clk, dsi->data_rate);
 	if (ret < 0) {
 		dev_err(dev, "Failed to set data rate: %d\n", ret);
-		goto err_refcount;
+		goto err_prepare_power;
 	}
 
 	phy_power_on(dsi->phy);
@@ -665,6 +672,11 @@ static int mtk_dsi_poweron(struct mtk_dsi *dsi)
 	clk_disable_unprepare(dsi->engine_clk);
 err_phy_power_off:
 	phy_power_off(dsi->phy);
+err_prepare_power:
+	if (dsi->panel) {
+		if (panel_unprepare_power(dsi->panel))
+			DRM_INFO("Can't unprepare power the panel\n");
+	}
 err_refcount:
 	dsi->refcount--;
 	return ret;
@@ -698,6 +710,11 @@ static void mtk_dsi_poweroff(struct mtk_dsi *dsi)
 	clk_disable_unprepare(dsi->digital_clk);
 
 	phy_power_off(dsi->phy);
+
+	if (dsi->panel) {
+		if (panel_unprepare_power(dsi->panel))
+			DRM_INFO("Can't unprepare power the panel\n");
+	}
 }
 
 static void mtk_output_dsi_enable(struct mtk_dsi *dsi)
@@ -1001,7 +1018,6 @@ static int mtk_dsi_probe(struct platform_device *pdev)
 {
 	struct mtk_dsi *dsi;
 	struct device *dev = &pdev->dev;
-	struct drm_panel *panel;
 	struct resource *regs;
 	int irq_num;
 	int ret;
@@ -1019,12 +1035,12 @@ static int mtk_dsi_probe(struct platform_device *pdev)
 	}
 
 	ret = drm_of_find_panel_or_bridge(dev->of_node, 0, 0,
-					  &panel, &dsi->next_bridge);
+					  &dsi->panel, &dsi->next_bridge);
 	if (ret)
 		goto err_unregister_host;
 
-	if (panel) {
-		dsi->next_bridge = devm_drm_panel_bridge_add(dev, panel);
+	if (dsi->panel) {
+		dsi->next_bridge = devm_drm_panel_bridge_add(dev, dsi->panel);
 		if (IS_ERR(dsi->next_bridge)) {
 			ret = PTR_ERR(dsi->next_bridge);
 			goto err_unregister_host;
-- 
2.12.5