Hi! > | > And latency may be ignorable in a laptop environment, but it absolutely > | > isn't in embedded devices, which users expect to operate immediately, as > | > though they were gear-driven rather than computer-driven. > | > | What latency are you talking about? Powering up piece of hw takes one > | milisecond or something. If your /dev/dsp takes 3 seconds to power up, > | you probably need userspace policy daemon. But that is not the case, > | hw takes few miliseconds to wake up. > > Sure, but *some* devices take substantially longer to power up or > down. If you insist that the driver should make the power down > decision, then you lump high-latency and low-latency devices together, > even though high-latency devices might be better served by separating > the semantics. High-latency devices indeed may be served better by separating the semantics. Fortunately the high-latency (we are talking >50msec here, right?) are rare enough... Like "none" in most embedded systems... Actually only common high-latency device is harddrive (spinup/spindown), and that's already handled specially with userspace hooks. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
