On 10/07/2014 05:56 AM, Mark yao wrote:
On 2014年09月30日 21:31, Andrzej Hajda wrote:
Hi Mark,
Hi Andrzej, Sorry for replying late, I have a vacation before. Thanks for your review.
On 09/30/2014 03:03 PM, Mark Yao wrote:
From: Mark yao mark.yao@rock-chips.com
(...)
+#ifdef CONFIG_PM_SLEEP +static int rockchip_drm_suspend(struct drm_device *dev, pm_message_t state) +{
- struct drm_connector *connector;
- drm_modeset_lock_all(dev);
- list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
int old_dpms = connector->dpms;if (connector->funcs->dpms)connector->funcs->dpms(connector, DRM_MODE_DPMS_OFF);/* Set the old mode back to the connector for resume */connector->dpms = old_dpms;- }
- drm_modeset_unlock_all(dev);
- return 0;
+}
+static int rockchip_drm_resume(struct drm_device *dev) +{
- struct drm_connector *connector;
- drm_modeset_lock_all(dev);
- list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
if (connector->funcs->dpms)connector->funcs->dpms(connector, connector->dpms);- }
- drm_modeset_unlock_all(dev);
- drm_helper_resume_force_mode(dev);
- return 0;
+}
+static int rockchip_drm_sys_suspend(struct device *dev) +{
- struct drm_device *drm_dev = dev_get_drvdata(dev);
- pm_message_t message;
- if (pm_runtime_suspended(dev))
return 0;- message.event = PM_EVENT_SUSPEND;
- return rockchip_drm_suspend(drm_dev, message);
drm_dev can be NULL here, it can happen when system is suspended before all components are bound. It can also contain invalid pointer if after successfull drm initialization de-initialization happens for some reason.
Some workaround is to check for null here and set drvdata to null on master unbind. But I guess it should be protected somehow to avoid races in accessing drvdata.
So, can I use the way that check for null here and set drvdata to null on master unbind? I don't know which way is better to protect somehow.
It seems to be a core problem, I have proposed some solution using drm driver PM callbacks [1] but it appears these callbacks are obsolete, so different solution should be found. According to Russel probably some extension of component framework. As a temporary solution I guess null checks should work in most cases.
Regards Andrzej
[1]: https://lkml.org/lkml/2014/10/3/60
-Mark.
+}
+static int rockchip_drm_sys_resume(struct device *dev) +{
- struct drm_device *drm_dev = dev_get_drvdata(dev);
- if (!pm_runtime_suspended(dev))
return 0;- return rockchip_drm_resume(drm_dev);
Ditto.
Regards Andrzej