On Sun, 6 Jan 2019, Paul Elder wrote: > Implement the mechanism for optional explicit status stage for the MUSB > driver. This allows a function driver to specify what to reply for the > status stage. The functionality for an implicit status stage is > retained. > > Signed-off-by: Paul Elder <paul.el...@ideasonboard.com> > v1 Reviewed-by: Laurent Pinchart <laurent.pinch...@ideasonboard.com> > v1 Acked-by: Bin Liu <b-...@ti.com> > --- > No change from v3 > > Changes from v2: > - update call to usb_gadget_control_complete to include status > - since sending STALL from the function driver is now done with > usb_ep_set_halt, there is no need for the internal ep0_send_response to > take a stall/ack parameter; remove the parameter and make the function > only send ack, and remove checking for the status reply in the > usb_request for the status stage > > Changes from v1: > - obvious change to implement v2 mechanism laid out by 4/6 of this > series (send_response, and musb_g_ep0_send_response function has > been removed, call to usb_gadget_control_complete has been added) > - ep0_send_response's ack argument has been changed from stall > - last_packet flag in ep0_rxstate has been removed, since it is equal to > req != NULL > > drivers/usb/musb/musb_gadget.c | 2 ++ > drivers/usb/musb/musb_gadget_ep0.c | 23 +++++++++++++++++++++++ > 2 files changed, 25 insertions(+) > > diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c > index d3f33f449445..a7a992ab0c9d 100644 > --- a/drivers/usb/musb/musb_gadget.c > +++ b/drivers/usb/musb/musb_gadget.c > @@ -145,6 +145,8 @@ __acquires(ep->musb->lock) > > trace_musb_req_gb(req); > usb_gadget_giveback_request(&req->ep->end_point, &req->request); > + usb_gadget_control_complete(&musb->g, request->explicit_status, > + request->status);
I haven't paid much attention to this part of the patch series, not knowing much about musb. Still, it's clear that usb_gadget_control_complete should be called only for transfers on ep0. You need to test the endpoint value. Another problem: the completion handler may deallocate the request. Dereferencing request->expicit_status and request->status would then cause errors. Would it be preferable to call usb_gadget_control_complete before usb_gadget_giveback_request? If it gets done that way then the arguments could be simplified: we could pass a pointer to the request instead of the separate explicit_status and status values. Alan Stern
