On Friday, 3 August 2018 20:24:56 MSK Linus Walleij wrote: > On Thu, Aug 2, 2018 at 1:31 PM Stefan Agner <stefan@xxxxxxxx> wrote: > > A while back at least using those init lists were not well received even > > for GPIO/pinctrl drivers: > > > > https://lore.kernel.org/lkml/CACRpkdYk0zW12qNXgOstTLmdVDYacu0Un+8quTN+J_az > > Oic7AA@xxxxxxxxxxxxxx/T/#mf0596982324a6489b5537b0531ac5aed60a316ba > You shouldn't listen too much to that guy he's not trustworthy. > > > I still think we should make an exception for GPIO/pinctrl and use > > earlier initcalls. Platform GPIO/pinctrl drivers provide basic > > infrastructure often used by many other drivers, we want to have them > > loaded early. It avoids unnecessary EPROBE_DEFER and hence probably even > > boots faster. > > When we have the pin control and GPIO at different initlevels it makes me > uneasy because I feel we have implicit init dependencies that seem more > than a little fragile. Yes, it is not very good. > My recent thinking has involved the component method used in DRM drivers > such as drivers/gpu/drm/vc4/vc4_drv.c where a few different component > subdrivers are linked together at bind time (not probe time!) into a master > component. > Rob was no big fan of this but the DRM people like it and I was thinking to > make a try at it. > > This way we could at least probe and bind the pin control and GPIO drivers > at the *same* initlevel and express the dependencies between them > somewhat. Sounds interesting, maybe you could help to convert Tegra drivers to a such method and others will follow afterwards. > > This should definitely go in, at least as a stop gap solution. > > Agreed. (And patch applied.) The best solution will be to fix the deferred probing, it's awkward that it could break suspend-resume order. Hopefully somebody with a good knowledge of driver/base will manage to fix it eventually. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
