[PATCH v4 18/51] drm/omap: dss: Cleanup DSS ports on initialisation failure

[Laurent Pinchart]

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 at xs4all.nl>
Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen at ti.com>
Acked-by: Sam Ravnborg <sam at ravnborg.org>
---
 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)
-- 
Regards,

Laurent Pinchart