Hi Felipe & Alan, To continue with topic discussed at http://www.spinics.net/lists/linux-usb/msg105279.html, I implement the gadget bus to bind udc to gadget driver follow most ideas from your two. Now this problem is really annoying, many gadget build-in platforms (Eg, Android) will fail to enable usb peripheral function due to udc is probe deferral, I hope we can fix this problem asap. The current "udc class" design can't cover auto-bind/manual bind by device model, so the first patch changes "udc class" to "gadget bus". The second patch adds the implementation of gadget bus, and the udc will bind to gadget driver automatically when they are matched. The rule of auto-binding is: if the udc is not in use and the gadget driver is not used by any udcs, it is matched successfully, and will be binded. Each gadget driver can only be binded at one udc. For example, there are two udcs, "udc-0" and "udc-1", and two gadget drivers, "g_mass_storage" and "g_serial", assumed the udcs is added to bus first, then, the "udc-0" will be binded to "g_mass_storage", and "udc-1" will be binded to "g_seiral". The third patch adds one "tricky" solution for manual bind if both udc and gadget driver are built in. The fifth patch delete the __init marker from all gadget driver's bind function, since the bind may not be executed after gadget driver has loaded due to udc is not ready. Below tests are done: One gadget driver build in and two udcs, udc devices are created first One gadget driver build in and two udcs, gadget driver is created first Two gadget driver build as modules and two udcs build in Two gadget driver build as modules and the udc driver build as module, and no matter which is loaded first. Manual binding/unbinding with different udcs: - Both udc and gadget driver are build in, udc-core.manual_binding=1 echo 0 > /sys/module/udc_core/parameters/manual_binding echo udc-0 > /sys/bus/usb_gadget/drivers/g_serial/bind echo udc-0 > /sys/bus/usb_gadget/drivers/g_serial/unbind echo udc-1 > /sys/bus/usb_gadget/drivers/g_serial/bind echo udc-1 > /sys/bus/usb_gadget/drivers/g_serial/unbind echo udc-0 > /sys/bus/usb_gadget/drivers/g_serial/bind - After auto-bind, unbind current udc and do manual bind echo udc-0 > /sys/bus/usb_gadget/drivers/g_serial/unbind echo udc-1 > /sys/bus/usb_gadget/drivers/g_serial/bind P.S: The mass storage gadget driver still not has problem if unload udc before unload gadget driver due to device_release_driver is called recursion (test_and_clear_bit is called by msg_thread_exits first), I will try to post a patch to fix it. Peter Chen (4): usb: gadget: core: change udc class to gadget bus usb: gadget: core: add implementation of gadget bus usb: gadget: core: add manual binding usb: gadget: remove __init from gadget driver bind function drivers/usb/gadget/acm_ms.c | 4 +- drivers/usb/gadget/audio.c | 4 +- drivers/usb/gadget/cdc2.c | 4 +- drivers/usb/gadget/dbgp.c | 4 +- drivers/usb/gadget/ether.c | 6 +- drivers/usb/gadget/f_hid.c | 6 +- drivers/usb/gadget/f_midi.c | 12 +- drivers/usb/gadget/f_uac1.c | 12 +- drivers/usb/gadget/f_uac2.c | 2 +- drivers/usb/gadget/f_uvc.c | 28 +++--- drivers/usb/gadget/gmidi.c | 4 +- drivers/usb/gadget/hid.c | 6 +- drivers/usb/gadget/mass_storage.c | 4 +- drivers/usb/gadget/multi.c | 4 +- drivers/usb/gadget/ncm.c | 4 +- drivers/usb/gadget/nokia.c | 4 +- drivers/usb/gadget/printer.c | 6 +- drivers/usb/gadget/serial.c | 2 +- drivers/usb/gadget/u_uac1.c | 2 +- drivers/usb/gadget/udc-core.c | 234 ++++++++++++++++++++++++------------- drivers/usb/gadget/webcam.c | 4 +- drivers/usb/gadget/zero.c | 2 +- 22 files changed, 216 insertions(+), 142 deletions(-) -- 1.7.8 -- 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
