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: 249f0a25 ("usb: cdns3: gadget: handle sg list use case at completion correctly")
cc: <stable@vger.kernel.org>
Acked-by: Peter Chen <peter.chen@kernel.org>
Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Link: https://lore.kernel.org/r/20220825062207.5824-1-pawell@cadence.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>