On Sat, Jan 23, 2021 at 4:35 PM Jonathan Cameron <jic23@xxxxxxxxxx> wrote: > [Me] > > Next, I think it is better to let suspend/resume, i.e. system PM > > reuse runtime PM since you're implementing that. This is why > > we invented PM runtime force resume and force suspend. > > Here the driver is turning more off for full suspend than in the > runtime path. If that results in significant extra delay then > it's not appropriate to have that in the runtime suspend path. I see the point. The resume path calls bmi088_accel_enable() which incurs a 5ms delay. The runtime resume path incurs a 1 ms delay. The runtime autosuspend kicks in after 2 ms. > Maybe the simplification of not doing the deeper power saving > mode is worth the extra power cost or extra delay, but > I'm not yet convinced. I would personally set the autosuspend to ~20ms and just use one path and take a hit of 5 ms whenever we go down between measures if it is a system that is for human interaction, but for control systems this more complex set-up may be better for response latencies. The current approach may be better tuned to perfection and we are all perfectionists :D I'm just worrying a little about bugs and maintainability. Yours, Linus Walleij
