On Wed, 27 Oct 2010, Hong Liu wrote: > In apds9802als_resume, I just want to power up the device, do some > configuration, and then runtime_suspend the device. Then you should change the function the way I suggested. The PM core will automatically do a runtime suspend after the system has fully woken up. > We don't have runtime_idle() implemented, the driver exported sysfs > entries to user space for data reading, and we do runtime_resume, > measaure data, runtime_suspend in the read/write funciton of those sysfs > entries. This is why I want to put the device into runtime suspend > manually whenever possible. Your approach will not work. You _must_ define runtime_idle() if you want your driver to suspend correctly. It doesn't have to be complicated; just make it call pm_runtime_suspend(). ... > We don't have runtime_idle() implemented, so I have to manually put the > device into runtime suspend. The problem is that the device can be runtime-resumed by code other than your own, and that other code will not always do a runtime-suspend afterward -- it will do a runtime-idle. That's why you need to define a runtime_idle() callback. Alan Stern _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
