* Johan Hovold <johan@xxxxxxxxxx> [231006 08:03]: > On Fri, Oct 06, 2023 at 10:27:38AM +0300, Tony Lindgren wrote: > > * Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> [231005 12:01]: > > > On Thu, Oct 05, 2023 at 10:56:42AM +0300, Tony Lindgren wrote: > > > > The serdev device and the serial core controller devices are siblings of > > > > the serial port hardware device. The runtime PM usage count from serdev > > > > > > I'm a bit lost in terminology here. > > > AFAIU there are: > > > 1) children of the serial physical device; > > > 2) siblings (to each other). > > > > > > But may be I mistakenly deciphered the diagram from the previous discussion. > > > > You're right, so how about: > > > > The serdev device and the serial core controller devices are children of > > the serial port hardware device. The runtime PM usage count from serdev > > device does not propagate to the serial core device siblings, it only > > propagates to the parent. > > That's still not accurate: > > - the serdev device is not a child (but a grandchild) of the serial > controller > - the new serial port devices are not "siblings" (but descendants) of > the serial controller > - the serdev controller ignores the power state of its children so that > bit is also incorrect > > You just want to describe the fact that the serdev controller runtime PM > state is currently not propagated to your new "devices" that are > descendants to the serial controller. OK so let's just use: The serdev controller runtime PM state is not currently propagated to the serial core controller port device. The runtime PM usage count only propagates to the parent device. > I'm still not sure why it was implemented this way, or if it is even > correct, but this seems to be the state of things. Care to clarify a bit which parts are unclear? The hierarchy of port devices, making serial core manage runtime PM in a generic way, or flushing tx? Regards, Tony
