On 06/22/2013 03:17 PM, Rafael J. Wysocki wrote: > On Saturday, June 22, 2013 02:11:14 PM Shuah Khan wrote: >> Add a new interface get_pm_transition() to return pm_transition state. >> This interface is intended to be used from dev_pm_ops class and type >> suspend interfaces that call legacy pm ops driver suspend interfaces. >> Legacy suspend pm_ops take pm_message_t as a parameter. >> >> e.g: drm_class_suspend() calls into driver suspend routines >> via drm_dev->driver->suspend(drm_dev, state). >> >> Once drm_class_suspend() is converted to dev_pm_ops, it will no longer >> have access to pm_transition which it has to pass into driver legacy >> suspend calls. get_pm_transition() interface addresses this need. > > That shouldn't be necessary because each transition has its own callback > in strict dev_pm_ops. > > Thanks, > Rafael > Yes that is correct that there is no need pass in or know pm_transition with dev_pm_ops. The issue I am running into is the legacy pm_ops class suspend/resume routines call. In the example, I mentioned in my changelog, drm_class_suspend() calls legacy pm_ops and passes in state. It passes in the state to the driver legacy suspend routine. I have seen code paths in drivers that differentiate between PM_EVENT_FREEZE, PM_EVENT_SUSPEND, PM_EVENT_SLEEP etc. I considered passing PM_EVENT_SUSPEND to drm_dev->driver->suspend(drm_dev, state) from drm_class_suspend() which would eliminate the need for this new interface. However, I am concerned about breaking driver legacy suspend routines that key of off the state to execute different code paths for PM_EVENT_FREEZE vs. PM_EVENT_SUSPEND. Suspend routines get called when state is is PM_EVENT_FREEZE based on my testing. I would rather not add a new interface. Hoping you will have another idea on how to pass in the state to legacy suspend/resume without adding this new interface. My thinking is that this new interface is temporary measure until all of the legacy suspend routines get converted to dev_pm_ops and at the tile legacy interface gets removed, this new interface can go away as well. thanks, -- Shuah Shuah Khan, Linux Kernel Developer - Open Source Group Samsung Research America (Silicon Valley) shuah.kh@xxxxxxxxxxx | (970) 672-0658 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
