> From: Bartlomiej Zolnierkiewicz [mailto:b.zolnierkie@xxxxxxxxxxx] > Sent: Friday, September 19, 2014 7:50 AM > > Unfortunately after second look there are even more problems with Kconfig > changes, please see below. > > > > > > >> if USB_DWC2 > > >> > > >> +choice > > >> + bool "DWC2 Mode Selection" > > >> + default USB_DWC2_DUAL_ROLE if (USB && USB_GADGET) > > >> + default USB_DWC2_HOST if (USB && !USB_GADGET) > > >> + default USB_DWC2_PERIPHERAL if (!USB && USB_GADGET) > > Previously it was possible to have following functionalities in > one kernel (for multiplatform kernels): > > - host PCI support > - host platform support > - gadget platform support > > Now mode selection will determine the used mode for combined > host+gadget platform driver. It is no longer possible to have > host platform and gadget platform support in one kernel. Why not? Why wouldn't it work if you enable USB_DWC2_DUAL_ROLE? The dwc3 driver uses the same scheme as this, and I have not heard any complaints about that not working. > Also there is only one mode selection for both PCI and platform > drivers so it is no longer possible to have both gadget platform > support and host PCI support in one kernel. There will be, once I update the dwc2 PCI support to include the gadget functionality. Then, if you enable USB_DWC2_DUAL_ROLE and DWC2_PCI, you should be set. In the meantime, I believe the only platform today that needs PCI support for dwc2 is our internal Synopsys development board, which is not an ARM platform. So I don't think there is a real issue here. > I think it would be the best to replace global mode selection > choice option with just two independent suboptions for combined > host+gadget platform driver which will enable host and gadget > support to be compiled into the driver (you would need to enable > both for dual role support). The actual selection of the mode > used should be done at runtime using device tree. See above. The dwc3 driver uses the same scheme as Dinh has implemented, and I don't think there have been any problems with it. -- Paul -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
