On Fri, May 19, 2023 at 04:30:41AM +0000, Badhri Jagan Sridharan wrote:
chipidea udc calls usb_udc_vbus_handler from udc_start gadget ops causing a deadlock. Avoid this by offloading usb_udc_vbus_handler processing.
Look, this is way overkill.
usb_udc_vbus_handler() has only two jobs to do: set udc->vbus and call usb_udc_connect_control(). Furthermore, it gets called from only two drivers: chipidea and max3420.
Why not have the callers set udc->vbus themselves and then call usb_gadget_{dis}connect() directly? Then we could eliminate usb_udc_vbus_handler() entirely. And the unnecessary calls -- the ones causing deadlocks -- from within udc_start() and udc_stop() handlers can be removed with no further consequence.
This approach simplifies and removes code. Whereas your approach complicates and adds code for no good reason.
Alan Stern