Hi, Peter Chen <hzpeterchen@xxxxxxxxx> writes: >> "Du, Changbin" <changbin.du@xxxxxxxxx> writes: >> > Hi, Balbi, >> > >> > The step to reproduce this issue is: >> > 1) connect device to a host and wait its enumeration. >> > 2) trigger software disconnect by calling function >> > usb_gadget_disconnect(), which finally call >> > dwc3_gadget_pullup(false). Do not reconnect device >> > (I mean no enumeration go on, keep bit Run/Stop 0.). >> > >> > At here, gadget driver's disconnect callback should be >> > Called, right? We has been disconnected. But no, as >> > You said " not generating disconnect IRQ after you >> > drop Run/Stop is expected". >> > >> > And I am testing on an Android device, Android only >> > use dwc3_gadget_pullup(false) to issue a soft disconnection. >> > This confused user that the UI still show usb as connected >> > State, caused by missing a disconnect event. >> >> okay, so I know what this is. This is caused by Android gadget itself >> not notifying the gadget that a disconnect has happened. Just look at >> udc-core's soft_connect implementation for the sysfs interface, and >> you'll see what I mean. >> >> This should be fixed at Android gadget itself. The only thing we could >> do is introduce a new usb_gadget_soft_connect()/disconnect() to wrap the >> logic so it's easier for Android gadget to use; but even that I'm a >> little bit reluctant to do because Android should be using our >> soft_connect interface instead of reimplementing it (wrongly) by its >> own. >> > > If it is a gadget driver, it can call its disconnect explicitly. > Another thing is the gadget driver should not call usb_gadget_disconnect > directly, it should call usb_gadget_deactivate or usb_function_deactivate. > > Since currently, calling usb_gadget_disconnect may not do real pull down > dp, Felipe, will you consider adding gadget_driver->disconnect into > usb_gadget_disconnect after pull down dp? this is the detail that I'm not yet entirely sure is always valid. Would there ever be a situation where we want to drop pull-ups but not tell the gadget about it ? I'm not sure. Anybody wants to investigate ? Otherwise I'll add it to my TODO list. -- balbi
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