usb: dwc3: core: Only handle soft-reset in DCTL

commit f4fd84ae0765a80494b28c43b756a95100351a94 upstream.

Make sure not to set run_stop bit or link state change request while
initiating soft-reset. Register read-modify-write operation may
unintentionally start the controller before the initialization completes
with its previous DCTL value, which can cause initialization failure.

Fixes: f59dcab17629 ("usb: dwc3: core: improve reset sequence")
Cc: <stable@vger.kernel.org>
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/6aecbd78328f102003d40ccf18ceeebd411d3703.1650594792.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 951d02b864bbbc3b77fde7a37e0ec81db36ec689..5cb1350ec66d1e42721daf33bce47c3aaf36b014 100644 (file)
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -275,7 +275,8 @@ static int dwc3_core_soft_reset(struct dwc3 *dwc)
 
        reg = dwc3_readl(dwc->regs, DWC3_DCTL);
        reg |= DWC3_DCTL_CSFTRST;
-       dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+       reg &= ~DWC3_DCTL_RUN_STOP;
+       dwc3_gadget_dctl_write_safe(dwc, reg);
 
        /*
         * For DWC_usb31 controller 1.90a and later, the DCTL.CSFRST bit