Hi! > >> This seems to look for "pwm0" and "pwm1" strings, which do not seem to > >> be documented. > >> > >> Plus... is it useful to have default-state? We already have default > >> trigger. If we keep the value by default (on PC, we do something like > >> that) this patch should not be neccessary? > > > > Thanks for the heads-up. Dropping the patch for now. > > No, please do not drop the patch. > > > I guess that pwm0/1 got propagated to v2 by an omission. > > Yes, I agree. However the two strings do not break anything and behave > analog to the 'on' or 'keep' string. Though this code could be removed > if absolutely necessary. An alternative would be to add a description > for the strings. Just to be clear: these strings have nothing to with > the exposition of device specific registers to the DT. Well, they should be removed. No need to keep surprises in code. > > Regarding default-on: Felix, do you have any use case that require > > default-on set to "keep"? > > This patch is not about 'default-on' which is a value that could be > assigned to the property 'linux,default-trigger' (according to DT > bindings documentation file 'common.txt'). > My patch does not introduce anything new with the'keep' state, it rather > completes the existing bindings according to the description in > Documentation/devicetree/bindings/leds/common.txt which states: Hmm, that was introduce by 1d1a77ddc8acfa3d506f1958e09a12085e71fc69 . I don't quite like the patch -- it duplicates default-trigger functionality without good reason. IMO we should 1) keep the led state by default 2) deprecate the default-state property 3) use default-triggers to emulate the functionality if someone really needs it. > One of my use cases is to turn a LED on by U-Boot. This LED must remain > on until eventually, under certain conditions, some userland code > changes it's state. > Setting 'default-state' to 'keep' is how you can sort of tell the > kernel, or better the driver, 'not to initialize the LED' which would > turn it off. Yes, that's reasonable. Perhaps 'keep' should be the default. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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