[PATCH 1/3] drm/ast: Handle failed I2C initialization gracefully
Thomas Zimmermann
tzimmermann at suse.de
Wed Dec 1 15:30:58 UTC 2021
I2C initialization is allowed to fail. In this case, create a connector
without DDC adapter. The current code would dereference a NULL pointer.
Reading the modes from the connector is supposed to work without I2C
adapter. Add the respective test.
Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
---
drivers/gpu/drm/ast/ast_mode.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index 1e30eaeb0e1b..3f0c8c1f9777 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -1226,7 +1226,7 @@ static int ast_get_modes(struct drm_connector *connector)
else
kfree(edid);
}
- if (!flags)
+ if (!flags && ast_connector->i2c)
edid = drm_get_edid(connector, &ast_connector->i2c->adapter);
if (edid) {
drm_connector_update_edid_property(&ast_connector->base, edid);
@@ -1332,10 +1332,13 @@ static int ast_connector_init(struct drm_device *dev)
if (!ast_connector->i2c)
drm_err(dev, "failed to add ddc bus for connector\n");
- drm_connector_init_with_ddc(dev, connector,
- &ast_connector_funcs,
- DRM_MODE_CONNECTOR_VGA,
- &ast_connector->i2c->adapter);
+ if (ast_connector->i2c)
+ drm_connector_init_with_ddc(dev, connector, &ast_connector_funcs,
+ DRM_MODE_CONNECTOR_VGA,
+ &ast_connector->i2c->adapter);
+ else
+ drm_connector_init(dev, connector, &ast_connector_funcs,
+ DRM_MODE_CONNECTOR_VGA);
drm_connector_helper_add(connector, &ast_connector_helper_funcs);
--
2.34.0
More information about the dri-devel
mailing list