On 22-08-25 08:22:07, Pawel Laszczak wrote:

The TRB_SMM flag indicates that DMA has completed the TD service with this TRB. Usually it’s a last TRB in TD. In case of ISOC transfer for bInterval > 1 each ISOC transfer contains more than one TD associated with usb request (one TD per ITP). In such case the TRB_SMM flag will be set in every TD and driver will recognize the end of transfer after processing the first TD with TRB_SMM. In result driver stops updating request->actual and returns incorrect actual length. To fix this issue driver additionally must check TRB_CHAIN which is not used for isochronous transfers.

Fixes: 249f0a25e8be ("usb: cdns3: gadget: handle sg list use case at completion correctly") cc: stable@vger.kernel.org Signed-off-by: Pawel Laszczak pawell@cadence.com

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

---

drivers/usb/cdns3/cdns3-gadget.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/cdns3/cdns3-gadget.c b/drivers/usb/cdns3/cdns3-gadget.c index fa8263951e63..a6618a922c61 100644 --- a/drivers/usb/cdns3/cdns3-gadget.c +++ b/drivers/usb/cdns3/cdns3-gadget.c @@ -1529,7 +1529,8 @@ static void cdns3_transfer_completed(struct cdns3_device *priv_dev, TRB_LEN(le32_to_cpu(trb->length)); if (priv_req->num_of_trb > 1 &&

• 			le32_to_cpu(trb->control) & TRB_SMM)
  

• 			le32_to_cpu(trb->control) & TRB_SMM &&
  

• 			le32_to_cpu(trb->control) & TRB_CHAIN)
  		transfer_end = true;
  

cdns3_ep_inc_deq(priv_ep); -- 2.25.1