This is a note to let you know that I've just added the patch titled usb: cdnsp: fix lack of ZLP for ep0 to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: usb-cdnsp-fix-lack-of-zlp-for-ep0.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From ae423ef5d095e09970f52c08020fdbf7f9d87c22 Mon Sep 17 00:00:00 2001 From: Pawel Laszczak <pawell@xxxxxxxxxxx> Date: Tue, 22 Nov 2022 03:51:38 -0500 Subject: usb: cdnsp: fix lack of ZLP for ep0 From: Pawel Laszczak <pawell@xxxxxxxxxxx> commit ae423ef5d095e09970f52c08020fdbf7f9d87c22 upstream. Patch implements the handling of ZLP for control transfer. To send the ZLP driver must prepare the extra TRB in TD with length set to zero and TRB type to TRB_NORMAL. The first TRB must have set TRB_CHAIN flag, TD_SIZE = 1 and TRB type to TRB_DATA. Fixes: 3d82904559f4 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver") cc: <stable@xxxxxxxxxxxxxxx> Reviewed-by: Peter Chen <peter.chen@xxxxxxxxxx> Signed-off-by: Pawel Laszczak <pawell@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20221122085138.332434-1-pawell@xxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/cdns3/cdnsp-ring.c | 42 +++++++++++++++++++++++++++++++---------- 1 file changed, 32 insertions(+), 10 deletions(-) --- a/drivers/usb/cdns3/cdnsp-ring.c +++ b/drivers/usb/cdns3/cdnsp-ring.c @@ -2006,10 +2006,11 @@ int cdnsp_queue_bulk_tx(struct cdnsp_dev int cdnsp_queue_ctrl_tx(struct cdnsp_device *pdev, struct cdnsp_request *preq) { - u32 field, length_field, remainder; + u32 field, length_field, zlp = 0; struct cdnsp_ep *pep = preq->pep; struct cdnsp_ring *ep_ring; int num_trbs; + u32 maxp; int ret; ep_ring = cdnsp_request_to_transfer_ring(pdev, preq); @@ -2019,26 +2020,33 @@ int cdnsp_queue_ctrl_tx(struct cdnsp_dev /* 1 TRB for data, 1 for status */ num_trbs = (pdev->three_stage_setup) ? 2 : 1; + maxp = usb_endpoint_maxp(pep->endpoint.desc); + + if (preq->request.zero && preq->request.length && + (preq->request.length % maxp == 0)) { + num_trbs++; + zlp = 1; + } + ret = cdnsp_prepare_transfer(pdev, preq, num_trbs); if (ret) return ret; /* If there's data, queue data TRBs */ - if (pdev->ep0_expect_in) - field = TRB_TYPE(TRB_DATA) | TRB_IOC; - else - field = TRB_ISP | TRB_TYPE(TRB_DATA) | TRB_IOC; - if (preq->request.length > 0) { - remainder = cdnsp_td_remainder(pdev, 0, preq->request.length, - preq->request.length, preq, 1, 0); + field = TRB_TYPE(TRB_DATA); - length_field = TRB_LEN(preq->request.length) | - TRB_TD_SIZE(remainder) | TRB_INTR_TARGET(0); + if (zlp) + field |= TRB_CHAIN; + else + field |= TRB_IOC | (pdev->ep0_expect_in ? 0 : TRB_ISP); if (pdev->ep0_expect_in) field |= TRB_DIR_IN; + length_field = TRB_LEN(preq->request.length) | + TRB_TD_SIZE(zlp) | TRB_INTR_TARGET(0); + cdnsp_queue_trb(pdev, ep_ring, true, lower_32_bits(preq->request.dma), upper_32_bits(preq->request.dma), length_field, @@ -2046,6 +2054,20 @@ int cdnsp_queue_ctrl_tx(struct cdnsp_dev TRB_SETUPID(pdev->setup_id) | pdev->setup_speed); + if (zlp) { + field = TRB_TYPE(TRB_NORMAL) | TRB_IOC; + + if (!pdev->ep0_expect_in) + field = TRB_ISP; + + cdnsp_queue_trb(pdev, ep_ring, true, + lower_32_bits(preq->request.dma), + upper_32_bits(preq->request.dma), 0, + field | ep_ring->cycle_state | + TRB_SETUPID(pdev->setup_id) | + pdev->setup_speed); + } + pdev->ep0_stage = CDNSP_DATA_STAGE; } Patches currently in stable-queue which might be from pawell@xxxxxxxxxxx are queue-6.1/usb-cdnsp-fix-lack-of-zlp-for-ep0.patch