[PATCH 00/10] usb: dwc3: gadget: Revise preparation for extra TRBs

[PATCH 00/10] usb: dwc3: gadget: Revise preparation for extra TRBs

[Thinh Nguyen]

This series resolves various issues with ZLP handling and refactor handling of
TRBs. This series has too many changes comparing to the "[PATCH v3 0/4] usb:
dwc3: gadget: Fix TRB preparation" series so I created different series
instead.


Thinh Nguyen (10):
  usb: dwc3: gadget: Check MPS of the request length
  usb: dwc3: gadget: Reclaim extra TRBs after request completion
  usb: dwc3: gadget: Refactor preparing extra TRB
  usb: dwc3: gadget: Improve TRB ZLP setup
  usb: dwc3: ep0: Fix ZLP for OUT ep0 requests
  usb: dwc3: gadget: Return the number of prepared TRBs
  usb: dwc3: gadget: Check for number of TRBs prepared
  usb: dwc3: gadget: Set IOC if not enough for extra TRBs
  usb: dwc3: gadget: Refactor preparing last TRBs
  usb: dwc3: gadget: Rename misleading function names

 drivers/usb/dwc3/ep0.c    |  11 +-
 drivers/usb/dwc3/gadget.c | 262 +++++++++++++++++---------------------
 2 files changed, 124 insertions(+), 149 deletions(-)


base-commit: 2f45af92722ee6e78f12037af1870117bcae00d1
-- 
2.28.0

[PATCH 01/10] usb: dwc3: gadget: Check MPS of the request length

[Thinh Nguyen]

When preparing for SG, not all the entries are prepared at once. When
resume, don't use the remaining request length to calculate for MPS
alignment. Use the entire request->length to do that.

Cc: stable@vger.kernel.org
Fixes: 5d187c0454ef ("usb: dwc3: gadget: Don't setup more than requested")
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
---
 drivers/usb/dwc3/gadget.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index cb19d682bbac..44351078f833 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1098,6 +1098,8 @@ static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep,
 	struct scatterlist *s;
 	int		i;
 	unsigned int length = req->request.length;
+	unsigned int maxp = usb_endpoint_maxp(dep->endpoint.desc);
+	unsigned int rem = length % maxp;
 	unsigned int remaining = req->request.num_mapped_sgs
 		- req->num_queued_sgs;
 
@@ -1109,8 +1111,6 @@ static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep,
 		length -= sg_dma_len(s);
 
 	for_each_sg(sg, s, remaining, i) {
-		unsigned int maxp = usb_endpoint_maxp(dep->endpoint.desc);
-		unsigned int rem = length % maxp;
 		unsigned int trb_length;
 		unsigned int chain = true;
 
-- 
2.28.0

[PATCH 02/10] usb: dwc3: gadget: Reclaim extra TRBs after request completion

[Thinh Nguyen]

An SG request may be partially completed (due to no available TRBs).
Don't reclaim extra TRBs and clear the needs_extra_trb flag until the
request is fully completed. Otherwise, the driver will reclaim the wrong
TRB.

Cc: stable@vger.kernel.org
Fixes: 1f512119a08c ("usb: dwc3: gadget: add remaining sg entries to ring")
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
---
 drivers/usb/dwc3/gadget.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 44351078f833..6017263929f3 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2738,6 +2738,11 @@ static int dwc3_gadget_ep_cleanup_completed_request(struct dwc3_ep *dep,
 		ret = dwc3_gadget_ep_reclaim_trb_linear(dep, req, event,
 				status);
 
+	req->request.actual = req->request.length - req->remaining;
+
+	if (!dwc3_gadget_ep_request_completed(req))
+		goto out;
+
 	if (req->needs_extra_trb) {
 		unsigned int maxp = usb_endpoint_maxp(dep->endpoint.desc);
 
@@ -2753,11 +2758,6 @@ static int dwc3_gadget_ep_cleanup_completed_request(struct dwc3_ep *dep,
 		req->needs_extra_trb = false;
 	}
 
-	req->request.actual = req->request.length - req->remaining;
-
-	if (!dwc3_gadget_ep_request_completed(req))
-		goto out;
-
 	dwc3_gadget_giveback(dep, req, status);
 
 out:
-- 
2.28.0

[PATCH 05/10] usb: dwc3: ep0: Fix ZLP for OUT ep0 requests

[Thinh Nguyen]

The current ZLP handling for ep0 requests is only for control IN
requests. For OUT direction, DWC3 needs to check and setup for MPS
alignment.

Usually, control OUT requests can indicate its transfer size via the
wLength field of the control message. So usb_request->zero is usually
not needed for OUT direction. To handle ZLP OUT for control endpoint,
make sure the TRB is MPS size.

Cc: stable@vger.kernel.org
Fixes: c7fcdeb2627c ("usb: dwc3: ep0: simplify EP0 state machine")
Fixes: d6e5a549cc4d ("usb: dwc3: simplify ZLP handling")
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
---
 drivers/usb/dwc3/ep0.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index b0363e3ba4d1..5580caed8b0c 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -947,12 +947,16 @@ static void dwc3_ep0_xfer_complete(struct dwc3 *dwc,
 static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
 		struct dwc3_ep *dep, struct dwc3_request *req)
 {
+	unsigned int		trb_length = 0;
 	int			ret;
 
 	req->direction = !!dep->number;
 
 	if (req->request.length == 0) {
-		dwc3_ep0_prepare_one_trb(dep, dwc->ep0_trb_addr, 0,
+		if (!req->direction)
+			trb_length = dep->endpoint.maxpacket;
+
+		dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr, trb_length,
 				DWC3_TRBCTL_CONTROL_DATA, false);
 		ret = dwc3_ep0_start_trans(dep);
 	} else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket)
@@ -999,9 +1003,12 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
 
 		req->trb = &dwc->ep0_trb[dep->trb_enqueue - 1];
 
+		if (!req->direction)
+			trb_length = dep->endpoint.maxpacket;
+
 		/* Now prepare one extra TRB to align transfer size */
 		dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr,
-					 0, DWC3_TRBCTL_CONTROL_DATA,
+					 trb_length, DWC3_TRBCTL_CONTROL_DATA,
 					 false);
 		ret = dwc3_ep0_start_trans(dep);
 	} else {
-- 
2.28.0