Hello, On Tue, 2017-04-18 at 12:23 +0000, Alexey Brodkin wrote: > Hello Frank, > > On Mon, 2017-04-17 at 20:15 -0700, Frank Rowand wrote: > > > > On 04/13/17 05:33, Alexey Brodkin wrote: > > > > > > > > > DWC3 driver uses of_usb_get_phy_mode() which is > > > implemented in drivers/usb/phy/of.c and in bare minimal > > > configuration it might not be pulled in kernel binary. > > > > > > In case of ARC or ARM this could be easily reproduced with > > > "allnodefconfig" +CONFIG_USB=m +CONFIG_USB_DWC3=m. > > > > > > On building all ends-up with: > > > ---------------------->8------------------ > > > Kernel: arch/arm/boot/Image is ready > > > Kernel: arch/arm/boot/zImage is ready > > > Building modules, stage 2. > > > MODPOST 5 modules > > > ERROR: "of_usb_get_phy_mode" [drivers/usb/dwc3/dwc3.ko] undefined! > > > make[1]: *** [__modpost] Error 1 > > > make: *** [modules] Error 2 > > > ---------------------->8------------------ > > > > > > Signed-off-by: Alexey Brodkin <abrodkin@xxxxxxxxxxxx> > > > Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > > > Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> > > > Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> > > > Cc: Nicolas Pitre <nicolas.pitre@xxxxxxxxxx> > > > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > > > Cc: Felipe Balbi <balbi@xxxxxxxxxx> > > > Cc: Felix Fietkau <nbd@xxxxxxxx> > > > Cc: Jeremy Kerr <jk@xxxxxxxxxx> > > > Cc: linux-snps-arc@xxxxxxxxxxxxxxxxxxx > > > Cc: stable@xxxxxxxxxxxxxxx > > > --- > > > drivers/Makefile | 1 + > > > 1 file changed, 1 insertion(+) > > > > > > diff --git a/drivers/Makefile b/drivers/Makefile > > > index 2eced9afba53..8f8bdc9e3d29 100644 > > > --- a/drivers/Makefile > > > +++ b/drivers/Makefile > > > @@ -104,6 +104,7 @@ obj-$(CONFIG_USB_PHY) += usb/ > > > obj-$(CONFIG_USB) += usb/ > > > obj-$(CONFIG_PCI) += usb/ > > > obj-$(CONFIG_USB_GADGET) += usb/ > > > > > > > > > > > +obj-$(CONFIG_OF) += usb/ > > > > Would CONFIG_USB_SUPPORT make more sense? (And does it work?) > > Well I'm not really sure here. > > The problem was in missing "drivers/usb/phy/of.o" in "drivers/usb/built-in.o". > So I took a look at how components get enabled and saw quite mixed stuff. > > In "drivers/usb/phy/Makefile" we see: > ------------------------->8--------------------------- > obj-$(CONFIG_OF)» » » += of.o > ------------------------->8--------------------------- > > In "drivers/usb/Makefile" we see: > ------------------------->8--------------------------- > obj-$(CONFIG_USB_SUPPORT)» += phy/ > ------------------------->8--------------------------- > > From above I may conclude that your proposal should work as well > but it's more a question of which approach is safer and more future proof. > > Maybe it even worth adding the following to "drivers/usb/Makefile": > ------------------------->8--------------------------- > obj-$(CONFIG_USB_SUPPORT)» += phy/ > ------------------------->8--------------------------- I'm wondering if there're any other thoughts on this one? The patch fixes a real problem and it would be good to get this or similar fix upstream. -Alexey