On Sat, Sep 06, 2014 at 12:09:22AM +0000, Peter Chen wrote: > > > On Fri, Sep 05, 2014 at 08:44:08AM +0800, Peter Chen wrote: > > > On Thu, Sep 04, 2014 at 11:04:38AM -0400, Alan Stern wrote: > > > > On Thu, 4 Sep 2014, Peter Chen wrote: > > > > > > > > > Hi Felipe & Alan, how about using below steps for this > > > > > reset/vbus/pullup changes? It mainly uses Alan's suggestion. > > > > > > > > > > Step 1: > > > > > The initial implementation in the four gadget > > > > > drivers can be very simple: It calls the disconnect handler. > > > > > the ->reset is mandatory for all gadget drivers (currently, > > > > > only four, they are composite, configfs, gadgetfs , dbgp. > > > > > Step 2: > > > > > Add routines to udc-core to handle Vbus changes, function > > > > > activation changes, and resets. It will include three sub-steps, > > > > > from easy to hard: reset handler, vbus handler, and activation > > > > > handler. > > > > > > > > Perhaps the activation handler can be delayed until step 4. It > > > > won't get used until composite.c is modified to call it. > > > > > > > > > Step 3: > > > > > Modify all UDCs to call udc-core's reset and vbus handler, delete > > > > > usb_gadget_connect/usb_gadget_disconnect operation at all UDC > > drivers, > > > > > and delete invoking usb_gadget_connect unconditional at > > > > > udc_bind_to_driver Step 4: > > > > > Modify the composite.c to disable pullup for adding every function, and > > > > > enable pullup when necessary. > > > > > > > > Actually, composite.c should be modified to call the activation > > > > handler in udc-core, and then _that_ routine would adjust the pullup > > > > as necessary. > > > > > > > > This plan is okay with me. > > > > > > > > > > OK, let's put the function activation change to the last. If the > > > Felipe has no other comments, I will send the patch for step one next > > Monday. > > > > Please do, the thread already has too much information and we better put all > > that in code. Keep in mind that me and Alan have resurected an old patchset > > adding ->reset() callback to the gadget framework. If you want to take a look > > it's at [1] > > > > https://git.kernel.org/cgit/linux/kernel/git/balbi/usb.git/log/?h=gadget-add- > > reset-method > > > > Thanks, Felipe. > > It still takes gadget driver's ->reset as optional, but we want to > take it as mandatory per our discussion. right, I was going to change that but since you're already working on it I figured you might prefer doing it all yourself :-) cheers -- balbi
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