[PATCH v2 1/2] usb: dwc2: host: Fix missing device insertions

Julius Werner jwerner at chromium.org
Mon Nov 16 12:26:26 PST 2015

Another point to note, which I think is what prevents the flow Alan
suggested from working, is this little snippet in DWC2's hub_control
GetPortStatus callback:

                if (!hsotg->flags.b.port_connect_status) {
                         * The port is disconnected, which means the core is
                         * either in device mode or it soon will be.
                         * return 0's for the remainder of the port status
                         * since the port register can't be read if the core
                         * is in device mode.
                        *(__le32 *)buf = cpu_to_le32(port_status);

This is before it actually checks the register state of the port. So
it relies on dwc2_hcd_connect() and dwc2_hcd_disconnect() to be called
in the right order to give the correct answer for
USB_PORT_STAT_CONNECTION. This could maybe be improved but I don't
know what kind of weird interactions with device mode operation made
that snippet necessary in the first place.

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