On Thu, 19 May 2011, Davide Ciminaghi wrote: > I'm not completely sure about this. What we wanted to do was to avoid powering > down the mmc while it is physically writing data into its internal memory. > If we force a sync when the power loss warning event warning happens, > it is very difficult to be able to guarantee that all buffered data will be > written before power actually dies. So we preferred to follow another strategy: > let the mmc finish any running write operation, and then stop its request > queue. If power really goes down, then we hope that the file system journal > will fix things on next boot (yes, some data could get lost, but the fs should > still be mountable). On the other hand, if power resumes, nothing bad should > happen for user space processes. You could consider a totally different approach. Each platform will have a different set of high-power devices it wants to turn off when a power-loss warning occurs. So instead of changing the core PM interface, you could add a new "power_loss" notifier list. Only the most critical drivers would need to listen for notifications, and this could be different drivers on different platforms. Alan Stern _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
