[PATCH 2/6] drm/fsl-dcu: handle missing panel gracefully

From: Stefan Agner
Date: Sun Apr 17 2016 - 01:26:05 EST


If the device tree property fsl,panel is missing, drm_panel_attach
is called with a NULL pointer as first argument. Having a panel is
basically mandatory since RGB is the only supported connector.
Check if a panel node has been found, return -ENODEV and cleanup
otherwise.

Signed-off-by: Stefan Agner <stefan@xxxxxxxx>
---
drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c
index a07886f..819fe12 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c
@@ -171,14 +171,18 @@ int fsl_dcu_drm_connector_create(struct fsl_dcu_drm_device *fsl_dev,
DRM_MODE_DPMS_OFF);

panel_node = of_parse_phandle(fsl_dev->np, "fsl,panel", 0);
- if (panel_node) {
- fsl_dev->connector.panel = of_drm_find_panel(panel_node);
- if (!fsl_dev->connector.panel) {
- ret = -EPROBE_DEFER;
- goto err_sysfs;
- }
- of_node_put(panel_node);
+ if (!panel_node) {
+ dev_err(fsl_dev->dev, "fsl,panel property not found\n");
+ ret = -ENODEV;
+ goto err_sysfs;
+ }
+
+ fsl_dev->connector.panel = of_drm_find_panel(panel_node);
+ if (!fsl_dev->connector.panel) {
+ ret = -EPROBE_DEFER;
+ goto err_panel;
}
+ of_node_put(panel_node);

ret = drm_panel_attach(fsl_dev->connector.panel, connector);
if (ret) {
@@ -188,6 +192,8 @@ int fsl_dcu_drm_connector_create(struct fsl_dcu_drm_device *fsl_dev,

return 0;

+err_panel:
+ of_node_put(panel_node);
err_sysfs:
drm_connector_unregister(connector);
err_cleanup:
--
2.8.0