[PATCH 5.4 138/388] drm/omap: dss: Cleanup DSS ports on initialisation failure

From: Greg Kroah-Hartman
Date: Tue Sep 29 2020 - 08:07:46 EST


From: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>

[ Upstream commit 2a0a3ae17d36fa86dcf7c8e8d7b7f056ebd6c064 ]

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@xxxxxxxxx>
Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@xxxxxx>
Acked-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
Tested-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx>
Reviewed-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20200226112514.12455-22-laurent.pinchart@xxxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 4bdd63b571002..ac93dae2a9c84 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)
--
2.25.1