Re: [PATCH] usb: dwc3: gadget:Core consumes a trb software to fill a trb, in ISO

From: Felipe Balbi
Date: Fri Dec 22 2017 - 02:55:05 EST



Hi,

Lipengcheng <lpc.li@xxxxxxxxxxxxx> writes:

> Iso transmission, the current process is that all trb(HWO=1) is handled.
> Then core generate DWC3_DEPEVT_XFERNOTREADY event, Software begin refill
> trb, this will produce 0 length package, the patch is to achieve the core
> consumes a trb, and then the software fill a trb. Normally, there will never
> be DWC3_DEPEVT_XFERNOTREADY event and 0-length packet.
>
> Signed-off-by: l00229106 <lpc.li@xxxxxxxxxxxxx>

who is 100229106??

> ---
> drivers/usb/dwc3/gadget.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 981fd98..1e6c42e 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -2420,7 +2420,7 @@ static void dwc3_endpoint_transfer_complete(struct dwc3 *dwc,
> if (!dep->endpoint.desc)
> return;
>
> - if (!usb_endpoint_xfer_isoc(dep->endpoint.desc))
> + if (!usb_endpoint_xfer_isoc(dep->endpoint.desc) || (dep->flags & DWC3_EP_TRANSFER_STARTED))

this is wrong. isoc endpoints should NEVER be prestarted.

--
balbi