Hi Peter,

quoted

quoted

@@ -299,6 +306,7 @@ int cdns3_drd_init(struct cdns3 *cdns)
               cdns->version  = CDNS3_CONTROLLER_V0;
               cdns->otg_v1_regs = NULL;
               cdns->otg_regs = regs;
+               writel(0x1, &cdns->otg_v0_regs->simulate);
               dev_info(cdns->dev, "DRD version v0 (%08x)\n",
                        readl(&cdns->otg_v0_regs->version));
       } else {

I have confirmation from HW team that time that driver should wait after de-
selecting mode is 2-3ms for simulate mode. It's time when FSM is in
DRD_H_WAIT_VBUS_FAIL.
Driver cannot re-enable the host/device mode before this time has elapsed.

3 ms is the maximum time. Additionally, you can confirm the current FSM state by
reading the host_otg_state (bit 5:3) or dev_otg_state (2:0)  from OTGSTATE
register.

If bit 0 in simulate register is cleared the time is exactly 1s.

Thanks, Pawel.

Would you please add below changes in your next revision?
- Set bit 0 in simulate register

But it's used only for simulation environments to speed up simulation. 
On real platforms this bit should be cleared. I'm not sure if I can 
add some code related to simulation environment to driver. 
If yes then I must introduce the way, that allow to recognize this two modes. 
I could add module parameter or add additional config in Kconfig file.

- timeout logic for waiting host_otg_state or dev_otg_state at OTGSTATE
when switch to host or device.

I will add such code. 

Pawel