For years/decades now, I've been complaining when I see people use platform devices for things that are obviously NOT platform devices. To finally fix this up, here is a "faux bus" that should be used instead of a platform device for these tiny and "fake" devices that people create all over the place. The api is even simpler than the normal platform device api, just two functions, one to create a device and one to remove it. When a device is created, if a probe/release callback is offered, they will be called at the proper time in the device's lifecycle. When finished with the device, just destroy it and all should be good. This simple api should also hopefully provide for a simple rust binding to it given the simple rules and lifecycle of the pointer passed back from the creation function (i.e. it is alive and valid for as long as you have not called destroy on it.) I've also converted four different examples of platform device abuse, the dummy regulator driver, the USB phy code, the x86 microcode dvice, and the "regulator" device that wifi uses to load the firmware tables, to use this api. In all cases, the logic either was identical, or became simpler, than before, a good sign (side note, a bug was fixed in the usb phy code that no one ever noticed before). Note, unless there are major objections, I'm leaning toward getting patch 1 of this series merged during this -rc cycle so that all of the individual driver subsystem cleanups can go through those subsystems as needed, as well as allowing the rust developers to create a binding and get that merged easier. Having patch 1 merged on its own isn't going to cause any changes if no one uses it, so that should be fine. Changes from v2: - lots of cleanups to faux.c based on reviews, see patch 1 for details - actually tested the destroy device path, it worked first try! - added 3 more example drivers Greg Kroah-Hartman (5): driver core: add a faux bus for use when a simple device/bus is needed regulator: dummy: convert to use the faux bus USB: phy: convert usb_phy_generic logic to use a faux device x86/microcode: move away from using a fake platform device wifi: cfg80211: move away from using a fake platform device arch/x86/kernel/cpu/microcode/core.c | 14 +- drivers/base/Makefile | 2 +- drivers/base/base.h | 1 + drivers/base/faux.c | 196 +++++++++++++++++++++++++++ drivers/base/init.c | 1 + drivers/regulator/dummy.c | 37 ++--- drivers/usb/chipidea/ci_hdrc_pci.c | 2 +- drivers/usb/dwc2/pci.c | 4 +- drivers/usb/musb/mediatek.c | 4 +- drivers/usb/musb/mpfs.c | 4 +- drivers/usb/musb/tusb6010.c | 2 +- drivers/usb/phy/phy-generic.c | 9 +- include/linux/device/faux.h | 31 +++++ include/linux/usb/usb_phy_generic.h | 9 +- net/wireless/reg.c | 28 ++-- 15 files changed, 277 insertions(+), 67 deletions(-) create mode 100644 drivers/base/faux.c create mode 100644 include/linux/device/faux.h -- 2.48.1
