Re: [PATCH v2 1/1] usb: dwc3: fix Clear Stall EP command failure

[Felipe Balbi]

Hi John,

Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> writes:
> Commit 50c763f8c1bac ("usb: dwc3: Set the ClearPendIN bit on Clear
> Stall EP command") sets ClearPendIN bit for all IN endpoints of
> v2.60a+ cores. This causes ClearStall command fails on 2.60+ cores
> operating in HighSpeed mode.
>
> In page 539 of 2.60a specification:
>
> "When issuing Clear Stall command for IN endpoints in SuperSpeed
> mode, the software must set the "ClearPendIN" bit to '1' to
> clear any pending IN transcations, so that the device does not
> expect any ACK TP from the host for the data sent earlier."
>
> It's obvious that we only need to apply this rule to those IN
> endpoints that currently operating in SuperSpeed mode.
>
> Fixes: 50c763f8c1bac ("usb: dwc3: Set the ClearPendIN bit on Clear Stall EP command")
> Cc: <stable@xxxxxxxxxxxxxxx> # v4.7+
> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> ---
>  v1->v2:
>  - check current instead of maximum speed
>  - improve the commit message
>
>  drivers/usb/dwc3/gadget.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 7a8d3d8..4fd9fda 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -348,7 +348,8 @@ static int dwc3_send_clear_stall_ep_cmd(struct dwc3_ep *dep)
>  	 * IN transfers due to a mishandled error condition. Synopsys
>  	 * STAR 9000614252.
>  	 */
> -	if (dep->direction && (dwc->revision >= DWC3_REVISION_260A))
> +	if (dep->direction && (dwc->revision >= DWC3_REVISION_260A) &&
> +	    (dwc->gadget.speed >= USB_SPEED_SUPER))
>  		cmd |= DWC3_DEPCMD_CLEARPENDIN;
>  
>  	memset(&params, 0, sizeof(params));

since this is patching what you changed, can you have a look? It makes
sense to me.

-- 
balbi