* Frank Rowand <frowand.list@xxxxxxxxx> [160412 14:42]: > On 4/12/2016 1:34 PM, Tony Lindgren wrote: > > > > OK thanks for the clarification. I don't see why "fail-hw-incomplete" > > could not be set dynamically during the probe in some cases based > > on the SoC revision detection for example. So from that point of > > view using status with the "fail-sss" logic would make more sense. > > If the probe detects that the device should only be power managed > based on the SoC revision, then it would simply be one more > test added at the top of probe. The patch would change from: > > if (of_device_is_incomplete(pdev->dev.of_node)) { > > to: > > if (of_device_is_incomplete(pdev->dev.of_node) || socrev == XXX) { > > That code would be the same whether the property involved was > status or something else. Yeah that should work if we had a generic way to get the runtime socrev somehow :) I guess the closest thing is the ARM system_rev. > >> I would prefer to come up with a new boolean property (with a > >> standard name that any node binding could choose to implement) > >> that says something like "only power management is available for > >> this node, do not attempt to use any other feature of the node". > > > > Heh that's going to be a long property name :) How about > > unusable-incomplete-idle-only :) > > Or even pm-only. Maybe I got a little carried away with my > verbosity. :) That works for me unless somebody comes up with a better one. I can only think unusable-for-io, which is no better. > >> With that change, the bulk of your patch looks good, with > >> minor changes: > >> > >> __of_device_is_available() would not need to change. > >> > >> __of_device_is_incomplete() would change to check the new > >> boolean property. (And I would suggest renaming it to > >> something that conveys it is ok to power manage the > >> device, but do not do anything else to the device.) > > > > I'm fine with property too, but the runtime probe fail state > > changes worry me a bit with that one. > > I don't understand what the concern is. The change I suggested > would use exactly the same code for probe as the example patch > you provided, but just with a slight name change for the function. I guess I'm just wondering if using property vs status will make things harder to change during runtime. For example, let's assume u-boot needs to set some devices to "pm-only" state based on the SoC revision on a board. > > I think Rob also preferred to use the status though while we > > chatted at ELC? > > That is the impression I got too. We'll have to see if I can > convince him otherwise. Yeah let's wait for his comments. Tony -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html