From b9f67df6de40d4cadaa3eff6ecd4c3ea6f1e81e8 Mon Sep 17 00:00:00 2001
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Date: Wed, 26 Feb 2020 13:24:41 +0200
Subject: drm/omap: dss: Cleanup DSS ports on initialisation failure
Git-commit: 2a0a3ae17d36fa86dcf7c8e8d7b7f056ebd6c064
Patch-mainline: v5.7-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322

When the DSS initialises its output DPI and SDI ports, failures don't
clean up previous successfully initialised ports. This can lead to
resource leak or memory corruption. Fix it.

Reported-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200226112514.12455-22-laurent.pinchart@ideasonboard.com
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/omapdrm/dss/dss.c | 43 +++++++++++++++++++------------
 1 file changed, 26 insertions(+), 17 deletions(-)

diff --git a/drivers/gpu/drm/omapdrm/dss/dss.c b/drivers/gpu/drm/omapdrm/dss/dss.c
index 225ec808b01a..67b92b5d8dd7 100644
--- a/drivers/gpu/drm/omapdrm/dss/dss.c
+++ b/drivers/gpu/drm/omapdrm/dss/dss.c
@@ -1151,46 +1151,38 @@ static const struct dss_features dra7xx_dss_feats = {
 	.has_lcd_clk_src	=	true,
 };
 
-static int dss_init_ports(struct dss_device *dss)
+static void __dss_uninit_ports(struct dss_device *dss, unsigned int num_ports)
 {
 	struct platform_device *pdev = dss->pdev;
 	struct device_node *parent = pdev->dev.of_node;
 	struct device_node *port;
 	unsigned int i;
-	int r;
 
-	for (i = 0; i < dss->feat->num_ports; i++) {
+	for (i = 0; i < num_ports; i++) {
 		port = of_graph_get_port_by_id(parent, i);
 		if (!port)
 			continue;
 
 		switch (dss->feat->ports[i]) {
 		case OMAP_DISPLAY_TYPE_DPI:
-			r = dpi_init_port(dss, pdev, port, dss->feat->model);
-			if (r)
-				return r;
+			dpi_uninit_port(port);
 			break;
-
 		case OMAP_DISPLAY_TYPE_SDI:
-			r = sdi_init_port(dss, pdev, port);
-			if (r)
-				return r;
+			sdi_uninit_port(port);
 			break;
-
 		default:
 			break;
 		}
 	}
-
-	return 0;
 }
 
-static void dss_uninit_ports(struct dss_device *dss)
+static int dss_init_ports(struct dss_device *dss)
 {
 	struct platform_device *pdev = dss->pdev;
 	struct device_node *parent = pdev->dev.of_node;
 	struct device_node *port;
-	int i;
+	unsigned int i;
+	int r;
 
 	for (i = 0; i < dss->feat->num_ports; i++) {
 		port = of_graph_get_port_by_id(parent, i);
@@ -1199,15 +1191,32 @@ static void dss_uninit_ports(struct dss_device *dss)
 
 		switch (dss->feat->ports[i]) {
 		case OMAP_DISPLAY_TYPE_DPI:
-			dpi_uninit_port(port);
+			r = dpi_init_port(dss, pdev, port, dss->feat->model);
+			if (r)
+				goto error;
 			break;
+
 		case OMAP_DISPLAY_TYPE_SDI:
-			sdi_uninit_port(port);
+			r = sdi_init_port(dss, pdev, port);
+			if (r)
+				goto error;
 			break;
+
 		default:
 			break;
 		}
 	}
+
+	return 0;
+
+error:
+	__dss_uninit_ports(dss, i);
+	return r;
+}
+
+static void dss_uninit_ports(struct dss_device *dss)
+{
+	__dss_uninit_ports(dss, dss->feat->num_ports);
 }
 
 static int dss_video_pll_probe(struct dss_device *dss)
-- 
2.28.0