On Friday, January 5, 2018 1:41:31 AM CET Brian Norris wrote: > Hi, > > Trying to catch up on this thread... > > On Wed, Dec 27, 2017 at 01:57:07AM +0100, Rafael J. Wysocki wrote: > > On Tuesday, December 26, 2017 2:06:47 AM CET JeffyChen wrote: > > > Hi Rafael, > > > > > > Thanks for your reply :) > > > > > > On 12/26/2017 08:11 AM, Rafael J. Wysocki wrote: > > > >> >+ > > > >> >+ dn = pci_device_to_OF_node(ppdev); > > > >> >+ if (!dn) > > > >> >+ return 0; > > > >> >+ > > > >> >+ irq = of_irq_get_byname(dn, "wakeup"); > > > > Why is this a property of the bridge and not of the device itself? > > Wait, isn't 'dn' the port node, not the bridge node? I may be confused about the structure you have in DT. In the device hierarchy PCIe ports are represented as bridges. > > > That is suggested by Brian, because in that way, the wakeup pin would > > > not "tied to what exact device is installed (or no device, if it's a slot)." > > I believe my thinking has evolved a bit over time, and I definitely am > not the one true authority on this. I'll explain my main concerns, and > whatever solution resolves these concerns is fine with me. > > * I was primarily interested in avoiding handling WAKE# in the endpoint > drivers (e.g., as mwifiex is today). OK, everybody on this thread is interested in that. :-) > * I was also interested in not having to redefine a new DT device > node (with new "pciABCD,1234" compatible property) for each new device > attached. That just won't work for removable cards. So if you make it the property of a bridge, it should be fine (as long as the bridge itself is not removable). > I need to reread the rest of this thread a few times to really > understand what Rafael and Tony are discussing. But I feel like some of > this is still moving away from the second point above. > > > But I don't think it works when there are two devices using different WAKE# > > interrupt lines under the same bridge. Or how does it work then? We seem to have agreed that this case needs to be neglected here. The "wakeup-interrupt" property at the bridge level basically has to be defined as the wakeup interrupt for all devices on the bus under the bridge. Thanks, Rafael
