On 2/9/2022 8:15 PM, Fabrice Gasnier wrote:
> When the gadget driver hasn't been (yet) configured, and the cable is
> connected to a HOST, the SFTDISCON gets cleared unconditionally, so the
> HOST tries to enumerate it.
> At the host side, this can result in a stuck USB port or worse. When
> getting lucky, some dmesg can be observed at the host side:
> new high-speed USB device number ...
> device descriptor read/64, error -110
>
> Fix it in drd, by checking the enabled flag before calling
> dwc2_hsotg_core_connect(). It will be called later, once configured,
> by the normal flow:
> - udc_bind_to_driver
> - usb_gadget_connect
> - dwc2_hsotg_pullup
> - dwc2_hsotg_core_connect
>
> Fixes: 17f934024e84 ("usb: dwc2: override PHY input signals with usb role switch support")
> Signed-off-by: Fabrice Gasnier <fabrice.gasnier@xxxxxxxxxxx>
Acked-by: Minas Harutyunyan <Minas.Harutyunyan@xxxxxxxxxxxx>
> ---
> drivers/usb/dwc2/drd.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/usb/dwc2/drd.c b/drivers/usb/dwc2/drd.c
> index 1b39c47..9b6d44d 100644
> --- a/drivers/usb/dwc2/drd.c
> +++ b/drivers/usb/dwc2/drd.c
> @@ -130,8 +130,10 @@ static int dwc2_drd_role_sw_set(struct usb_role_switch *sw, enum usb_role role)
> already = dwc2_ovr_avalid(hsotg, true);
> } else if (role == USB_ROLE_DEVICE) {
> already = dwc2_ovr_bvalid(hsotg, true);
> - /* This clear DCTL.SFTDISCON bit */
> - dwc2_hsotg_core_connect(hsotg);
> + if (hsotg->enabled) {
> + /* This clear DCTL.SFTDISCON bit */
> + dwc2_hsotg_core_connect(hsotg);
> + }
> } else {
> if (dwc2_is_device_mode(hsotg)) {
> if (!dwc2_ovr_bvalid(hsotg, false))
