| Message ID | 20220825062207.5824-1-pawell@cadence.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | d5dcc33677d7415c5f23b3c052f9e80cbab9ea4e |
| Headers | show |
| Series | usb: cdns3: fix incorrect handling TRB_SMM flag for ISOC transfer | expand |
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 >
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);
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> --- drivers/usb/cdns3/cdns3-gadget.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)