On Mon, Feb 7, 2022 at 2:59 PM Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> wrote: > On Mon, 7 Feb 2022 09:04:41 +0000 > Massimo Toscanelli <massimo.toscanelli@xxxxxxxxxxxxxxxxxxxx> wrote: > The standard approach to avoiding rapid power up and power down cycles > is to use runtime_pm with autosuspend and a period set at a period > of perhaps 1 second. Would that work for you? You'll pay the costs > of power up only on the first read after a period of not reading. > > Exposing the control to userspace for this sort of thing is normally > a bad idea because userspace generally has no idea if it should use it > as there is no clean way of telling userspace the costs of not using > it (as those will be device specific). > > If you have a usecase that requires regular reading you should also > think about whether using the buffered interface is more appropriate. > IIRC that will keep these devices powered up continuously whilst > the buffer is enabled and will provide a lower overhead way of > reading data than sysfs reads. I see that I have repeted similar comments. Sorry for the hammering. I agree with Jonathan's stance here. Yours, Linus Walleij
