On Tue, Nov 15, 2022 at 5:22 PM Pawel Laszczak pawell@cadence.com wrote:
Patch modifies the TD_SIZE in TRB before ZLP TRB. The TD_SIZE in TRB before ZLP TRB must be set to 1 to force processing ZLP TRB by controller.
cc: stable@vger.kernel.org Fixes: 3d82904559f4 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver") Signed-off-by: Pawel Laszczak pawell@cadence.com
v2:
- returned value for last TRB must be 0
v3:
- fix issue for request->length > 64KB
drivers/usb/cdns3/cdnsp-ring.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/drivers/usb/cdns3/cdnsp-ring.c b/drivers/usb/cdns3/cdnsp-ring.c index 794e413800ae..86e1141e150f 100644 --- a/drivers/usb/cdns3/cdnsp-ring.c +++ b/drivers/usb/cdns3/cdnsp-ring.c @@ -1763,10 +1763,15 @@ static u32 cdnsp_td_remainder(struct
cdnsp_device *pdev,
int trb_buff_len, unsigned int td_total_len, struct cdnsp_request *preq,
bool more_trbs_coming)
bool more_trbs_coming,bool zlp){ u32 maxp, total_packet_count;
/* Before ZLP driver needs set TD_SIZE = 1. */if (zlp)return 1;Pawel, with your change, the TD_SIZE is 1 or 0, but not like the kernel doc defined like below:
Description is not added in kernel doc but is added before "if (zlp)".
I will add as last lines in kernel doc the description:
* * TD containing ZLP must have TD size set to one in penultimate TRB in TD. */
Will this patch be correct for you then?
Pawel
/*
- TD size is the number of max packet sized packets remaining in the TD
- (*not* including this TRB).
- Total TD packet count = total_packet_count =
DIV_ROUND_UP(TD size in bytes / wMaxPacketSize)- Packets transferred up to and including this TRB = packets_transferred =
rounddown(total bytes transferred including this TRB / wMaxPacketSize)- TD size = total_packet_count - packets_transferred
- It must fit in bits 21:17, so it can't be bigger than 31.
- This is taken care of in the TRB_TD_SIZE() macro
- The last TRB in a TD must have the TD size set to zero.
*/
Peter
/* One TRB with a zero-length data packet. */ if (!more_trbs_coming || (transferred == 0 && trb_buff_len == 0) || trb_buff_len == td_total_len) @@ -1960,7 +1965,8 @@ intcdnsp_queue_bulk_tx(struct cdnsp_device *pdev, struct cdnsp_request
*preq)
/* Set the TRB length, TD size, and interrupter fields. */ remainder = cdnsp_td_remainder(pdev, enqd_len, trb_buff_len, full_len, preq,
more_trbs_coming);
more_trbs_coming,zero_len_trb); length_field = TRB_LEN(trb_buff_len) | TRB_TD_SIZE(remainder) | TRB_INTR_TARGET(0); @@ -2025,7 +2031,7 @@ intcdnsp_queue_ctrl_tx(struct cdnsp_device *pdev, struct cdnsp_request *preq)
if (preq->request.length > 0) { remainder = cdnsp_td_remainder(pdev, 0, preq->request.length,
preq->request.length, preq, 1);
preq->request.length,preq, 1, 0);
length_field = TRB_LEN(preq->request.length) | TRB_TD_SIZE(remainder) |TRB_INTR_TARGET(0); @@ -2225,7 +2231,7 @@ static int
cdnsp_queue_isoc_tx(struct cdnsp_device *pdev,
/* Set the TRB length, TD size, & interrupter fields. */ remainder = cdnsp_td_remainder(pdev, running_total, trb_buff_len, td_len, preq,
more_trbs_coming);
more_trbs_coming, 0); length_field = TRB_LEN(trb_buff_len) |TRB_INTR_TARGET(0);
-- 2.25.1