On Sun, 2012-04-22 at 21:01 +0200, Sebastian Andrzej Siewior wrote: > * Greg KH | 2012-04-21 08:34:02 [-0700]: > > >> > CONFIG_MODULES is not enabled. > >> > CONFIG_TCM_USB_GADGET=y > >> > CONFIG_USB_GADGET=y > >> > >> Sebastian + Greg-KH (Cc'ed), any ideas why this is the case here..? > > > >I have no idea, sorry. > > The short version: > in order to fix this either move the usb-target-gadget to > drivers/usb/gadget/Kconfig and make sure only one gadget can be compiled > at a time or add some kind of depends. > > The longer version: > This is a short comming of the gadget framework. We are able to build > multiple UDCs at a time and we can build multiple gadgets _as_ modules. > Since we can not bind & configure via an interface the whole thing works > right now via "modprobe $gadget. There is some infrastructure to accept > multiple UDCs/gadget but the *whole* thing is not complete. > In non-modules mode you can only select one gadget at a time. With the > target gadget living outside of usb/gadget selection it is possible to > select both at the same time which causes the duplicate symbols here. > A "quick" fix is not to define all the functions static and put > maybe_unsued on each function to avoid warnings. This is only duct tape > on top and I would prefer that nobody is sending such a patch. The > result is hardly usefull by a user. > A real fix would to get rid of the "#includes foo.c" and use a helper > module/library instead. > I tried this once and notice that the whole thing relies on > static/global variables which are initialized once on modprobe. So > with the second module loaded (read as rmmod $mod1 && modprobe $mod2) > the gadget framework explodes. Once I noticed that, the patches got out > of Felipe's tree before anyone noticed something. That means we should > first get rid of the global variables and then maybe try again :) > Hey Sebastian & USB folks, So I'm catching up on for-next-merge stuff after being away last week, and ended up following your advice to just move tcm_usb_gadget code into drivers/usb/gadget/ in to address the legacy requirements above.. After the recommended change, the in-kernel config using a single gadget driver (the target) are able to build. Thanks for the detailed explanation btw.. ;) I've made the same change for tcm_usb_gadget in lio-core, and updated for-next-merge with the following merge patch: http://git.kernel.org/?p=linux/kernel/git/nab/target-pending.git;a=commit;h=0c41520201bc0933d65b8644173802778f426234 Please let me know if you have any other changes that should go into sunday's linux-next build. Thanks! --nab -- To unsubscribe from this list: send the line "unsubscribe target-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
