3.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jani Nikula <jani.nikula@xxxxxxxxx> commit dc652f90e088798bfa31f496ba994ddadd5d5680 upstream. Backlight cleanup in the eDP connector destroy callback caused the backlight device to be removed on some systems that first initialized LVDS and then attempted to initialize eDP. Prevent multiple backlight initializations, and ensure backlight cleanup is only done once by moving it to modeset cleanup. A small wrinkle is the introduced asymmetry in backlight setup/cleanup. This could be solved by adding refcounting, but it seems overkill considering that there should only ever be one backlight device. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=55701 Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> Tested-by: Peter Verthez <peter.verthez@xxxxxxxxx> Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/intel_display.c | 3 +++ drivers/gpu/drm/i915/intel_dp.c | 5 +---- drivers/gpu/drm/i915/intel_lvds.c | 1 - drivers/gpu/drm/i915/intel_panel.c | 7 ++++++- 4 files changed, 10 insertions(+), 6 deletions(-) --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -9388,6 +9388,9 @@ void intel_modeset_cleanup(struct drm_de /* flush any delayed tasks or pending work */ flush_scheduled_work(); + /* destroy backlight, if any, before the connectors */ + intel_panel_destroy_backlight(dev); + drm_mode_config_cleanup(dev); } --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -2467,17 +2467,14 @@ done: static void intel_dp_destroy(struct drm_connector *connector) { - struct drm_device *dev = connector->dev; struct intel_dp *intel_dp = intel_attached_dp(connector); struct intel_connector *intel_connector = to_intel_connector(connector); if (!IS_ERR_OR_NULL(intel_connector->edid)) kfree(intel_connector->edid); - if (is_edp(intel_dp)) { - intel_panel_destroy_backlight(dev); + if (is_edp(intel_dp)) intel_panel_fini(&intel_connector->panel); - } drm_sysfs_connector_remove(connector); drm_connector_cleanup(connector); --- a/drivers/gpu/drm/i915/intel_lvds.c +++ b/drivers/gpu/drm/i915/intel_lvds.c @@ -556,7 +556,6 @@ static void intel_lvds_destroy(struct dr if (!IS_ERR_OR_NULL(lvds_connector->base.edid)) kfree(lvds_connector->base.edid); - intel_panel_destroy_backlight(connector->dev); intel_panel_fini(&lvds_connector->base.panel); drm_sysfs_connector_remove(connector); --- a/drivers/gpu/drm/i915/intel_panel.c +++ b/drivers/gpu/drm/i915/intel_panel.c @@ -422,6 +422,9 @@ int intel_panel_setup_backlight(struct d intel_panel_init_backlight(dev); + if (WARN_ON(dev_priv->backlight)) + return -ENODEV; + memset(&props, 0, sizeof(props)); props.type = BACKLIGHT_RAW; props.max_brightness = _intel_panel_get_max_backlight(dev); @@ -447,8 +450,10 @@ int intel_panel_setup_backlight(struct d void intel_panel_destroy_backlight(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; - if (dev_priv->backlight) + if (dev_priv->backlight) { backlight_device_unregister(dev_priv->backlight); + dev_priv->backlight = NULL; + } } #else int intel_panel_setup_backlight(struct drm_connector *connector) -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html