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

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: f59dcab ("usb: dwc3: core: improve reset sequence")
Cc: <[email protected]>
Signed-off-by: Thinh Nguyen <[email protected]>
Link: https://lore.kernel.org/r/6aecbd78328f102003d40ccf18ceeebd411d3703.1650594792.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: Thinh Nguyen

drivers/usb/dwc3/core.c

@@ -274,7 +274,8 @@ 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