Re: [PATCH v2 3/3] usb: chipidea: udc: improve error recovery for ISO transfer

[Peter Chen <peter.chen@kernel.org>]

On 24-09-20 17:40:56, Xu Yang wrote:
> Impove device mode ISO transfer error tolerant by reprime the corresponding
> endpoint.
> 
> The recovery steps when error occurs:
> - Delete the error dTD from dQH and giveback request to user.
> - Do reprime if dQH is not empty.
> - Do prime when new dTD is queued if dQH is empty
> 
> Signed-off-by: Xu Yang <xu.yang_2@nxp.com>

Acked-by: Peter Chen <peter.chen@kernel.org>


> 
> ---
> Changes in v2:
>  - modify commit message
>  - keep "hwreq->req.status = tmptoken & TD_STATUS"
>  - giveback status 0 to user for isoc error case
> ---
>  drivers/usb/chipidea/udc.c | 13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
> index c0b8745234c6..e1121db0aea0 100644
> --- a/drivers/usb/chipidea/udc.c
> +++ b/drivers/usb/chipidea/udc.c
> @@ -823,6 +823,7 @@ static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
>  	unsigned remaining_length;
>  	unsigned actual = hwreq->req.length;
>  	struct ci_hdrc *ci = hwep->ci;
> +	bool is_isoc = hwep->type == USB_ENDPOINT_XFER_ISOC;
>  
>  	if (hwreq->req.status != -EALREADY)
>  		return -EINVAL;
> @@ -836,7 +837,7 @@ static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
>  			int n = hw_ep_bit(hwep->num, hwep->dir);
>  
>  			if (ci->rev == CI_REVISION_24 ||
> -			    ci->rev == CI_REVISION_22)
> +			    ci->rev == CI_REVISION_22 || is_isoc)
>  				if (!hw_read(ci, OP_ENDPTSTAT, BIT(n)))
>  					reprime_dtd(ci, hwep, node);
>  			hwreq->req.status = -EALREADY;
> @@ -855,11 +856,15 @@ static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
>  			hwreq->req.status = -EPROTO;
>  			break;
>  		} else if ((TD_STATUS_TR_ERR & hwreq->req.status)) {
> -			hwreq->req.status = -EILSEQ;
> -			break;
> +			if (is_isoc) {
> +				hwreq->req.status = 0;
> +			} else {
> +				hwreq->req.status = -EILSEQ;
> +				break;
> +			}
>  		}
>  
> -		if (remaining_length) {
> +		if (remaining_length && !is_isoc) {
>  			if (hwep->dir == TX) {
>  				hwreq->req.status = -EPROTO;
>  				break;
> -- 
> 2.34.1
>