Re: [PATCH 5/5] usb: dwc3: gadget: Increase DWC3 controller halt timeout

From: Thinh Nguyen
Date: Fri Jul 08 2022 - 21:48:02 EST


On 7/8/2022, Wesley Cheng wrote:
> Since EP0 transactions need to be completed before the controller halt
> sequence is finished, this may take some time depending on the host and the
> enabled functions. Increase the controller halt timeout, so that we give
> the controller sufficient time to handle EP0 transfers.
>
> Signed-off-by: Wesley Cheng <quic_wcheng@xxxxxxxxxxx>
> ---
> drivers/usb/dwc3/gadget.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index fba2797ad9ae..a5c0e39bd002 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -2487,6 +2487,7 @@ static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend)
> do {
> reg = dwc3_readl(dwc->regs, DWC3_DSTS);
> reg &= DWC3_DSTS_DEVCTRLHLT;
> + msleep(1);

I think it makes more sense to msleep() first before reading the register.

Thanks,
Thinh

> } while (--timeout && !(!is_on ^ !reg));
>
> if (!timeout)