Hi Michael, Thanks for the reply. I am a bit of old-school, and would prefer things in one place only (in the kernel) :) Thus : a) I wish to have all the endpoints configuration/management in the kernel only (like done in drivers/usb/gadget/function/f_serial.c, drivers/usb/gadget/function/u_serial.c). b) Only the attributes like vendorId/productId would be in configfs, to help setup the device. c) No user-space management of kernel objects. Either-way, I think that my issue of "function exposure" would remain the same, irrespective of whether we use configfs for managing the kernel-objects (please correct me if I am wrong). Thanks again for your time, look forward to listening back ! Thanks and Regards, Ajay On Sat, Sep 11, 2021 at 8:01 PM Michael Sweet <msweet@xxxxxxxxxx> wrote: > > Ajay, > > Quick question (as someone who has been down this road), do you need to do a kernel driver or could you just use the functionfs support to implement everything in userspace? I found that path to be much easier and less error-prone (and one of these days I'm going to be contributing some documentation changes to make some things clearer...) and I was able to get my IPP-USB implementation up and running very quickly. > > > > On Sep 11, 2021, at 1:43 AM, Ajay Garg <ajaygargnsit@xxxxxxxxx> wrote: > > > > Hi All. > > > > As a first step, I have been able to load a gadget on configfs, which > > binds to the function "gser" (thus loading up the usb_f_serial module > > when the gadget mounts). Things work well till here. > > > > Now, I have written a brand-new gadget-side device-driver, trying to > > create a new function "gusb", via DECLARE_USB_FUNCTION_INIT. > > However, now when I try to load the gadget for binding to "gusb", I > > get the error that the function cannot be found. > > > > Seems that firing up a new gadget-side driver, that registers a new > > function via DECLARE_USB_FUNCTION_INIT, is not enough to make the new > > function visible across the kernel. > > > > Kindly let know what I am missing. > > Will be grateful for pointers. > > > > > > Thanks and Regards, > > Ajay > > > > ________________________ > Michael Sweet > > >
