On Mon, Jul 22, 2019 at 09:58:42AM +0000, Pawel Laszczak wrote: > Hi, > > > > >> This patch introduce new Cadence USBSS DRD driver to linux kernel. > >> > >> The Cadence USBSS DRD Controller is a highly configurable IP Core which > >> can be instantiated as Dual-Role Device (DRD), Peripheral Only and > >> Host Only (XHCI)configurations. > > > >I see you are using debugfs to select between DRD, peripheral-onlyh and XHCI... > > > >Is that good idea? > > Yes driver allows selecting dr_mode by debugfs. Controller also support such functionality > so I don't understand why would it not be a good idea. > > I personally use this for testing but it can be used to limit controller functionality without > recompiling kernel. debugfs is ONLY for debugging, never rely on it being enabled, or mounted, on a system in order to have any normal operation happen. So for testing, yes, this is fine. If this is going to be the normal api/interface for how to control this driver, no, that is not acceptable at all. thanks, greg k-h