summary refs log tree commit diff
path: root/drivers/usb/cdns3
diff options
context:
space:
mode:
authorPawel Laszczak <pawell@cadence.com>2022-11-22 03:51:38 -0500
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2022-12-31 13:33:09 +0100
commitdfbbc47d8672a73679311df5acbeae6a6ff23dee (patch)
tree4ee0d0bc279cf2ace9081a0445e1ae26f25ea4b1 /drivers/usb/cdns3
parent5b7c3061067efaa82ce9833a6ea21ed7cf44c234 (diff)
downloadlinux-dfbbc47d8672a73679311df5acbeae6a6ff23dee.tar.gz
usb: cdnsp: fix lack of ZLP for ep0
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@vger.kernel.org>
Reviewed-by: Peter Chen <peter.chen@kernel.org>
Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Link: https://lore.kernel.org/r/20221122085138.332434-1-pawell@cadence.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/cdns3')
-rw-r--r--drivers/usb/cdns3/cdnsp-ring.c42
1 files changed, 32 insertions, 10 deletions
diff --git a/drivers/usb/cdns3/cdnsp-ring.c b/drivers/usb/cdns3/cdnsp-ring.c
index 2f29431f612e..b23e543b3a3d 100644
--- 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_device *pdev, struct cdnsp_request *preq)
 
 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_device *pdev, struct cdnsp_request *preq)
 	/* 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_device *pdev, struct cdnsp_request *preq)
 				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;
 	}