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

[John Youn <John.Youn@synopsys.com>]

On 9/9/2016 12:47 AM, Felipe Balbi wrote:
> 
> Hi John,
> 
> Lu Baolu <baolu.lu@linux.intel.com> 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@vger.kernel.org> # v4.7+
>> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
>> ---
>>  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.
> 

Looks good to me

John