summaryrefslogtreecommitdiff
path: root/drivers/usb
diff options
context:
space:
mode:
authorThinh Nguyen <Thinh.Nguyen@synopsys.com>2020-08-06 19:46:29 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-09-03 11:27:09 +0200
commit7c8b5685662b5fe7ec57ee875aad62da11226b5d (patch)
treee558d953cf62a457c9f106c3d5ab68d0ea782b22 /drivers/usb
parent4bc5d90a7dce113f95a85e6454773a8232019dc3 (diff)
usb: dwc3: gadget: Fix handling ZLP
[ Upstream commit d2ee3ff79e6a3d4105e684021017d100524dc560 ] The usb_request->zero doesn't apply for isoc. Also, if we prepare a 0-length (ZLP) TRB for the OUT direction, we need to prepare an extra TRB to pad up to the MPS alignment. Use the same bounce buffer for the ZLP TRB and the extra pad TRB. Cc: <stable@vger.kernel.org> # v4.5+ Fixes: d6e5a549cc4d ("usb: dwc3: simplify ZLP handling") Fixes: 04c03d10e507 ("usb: dwc3: gadget: handle request->zero") Signed-off-by: Thinh Nguyen <thinhn@synopsys.com> Signed-off-by: Felipe Balbi <balbi@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/usb')
-rw-r--r--drivers/usb/dwc3/gadget.c24
1 files changed, 22 insertions, 2 deletions
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 816216870a1b..8e67591df76b 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1159,6 +1159,7 @@ static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep,
req->request.short_not_ok,
req->request.no_interrupt);
} else if (req->request.zero && req->request.length &&
+ !usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
(IS_ALIGNED(req->request.length, maxp))) {
struct dwc3 *dwc = dep->dwc;
struct dwc3_trb *trb;
@@ -1168,13 +1169,23 @@ static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep,
/* prepare normal TRB */
dwc3_prepare_one_trb(dep, req, length, true, 0);
- /* Now prepare one extra TRB to handle ZLP */
+ /* Prepare one extra TRB to handle ZLP */
trb = &dep->trb_pool[dep->trb_enqueue];
req->num_trbs++;
__dwc3_prepare_one_trb(dep, trb, dwc->bounce_addr, 0,
- false, 1, req->request.stream_id,
+ !req->direction, 1, req->request.stream_id,
req->request.short_not_ok,
req->request.no_interrupt);
+
+ /* Prepare one more TRB to handle MPS alignment for OUT */
+ if (!req->direction) {
+ trb = &dep->trb_pool[dep->trb_enqueue];
+ req->num_trbs++;
+ __dwc3_prepare_one_trb(dep, trb, dwc->bounce_addr, maxp,
+ false, 1, req->request.stream_id,
+ req->request.short_not_ok,
+ req->request.no_interrupt);
+ }
} else {
dwc3_prepare_one_trb(dep, req, length, false, 0);
}
@@ -2578,8 +2589,17 @@ static int dwc3_gadget_ep_cleanup_completed_request(struct dwc3_ep *dep,
status);
if (req->needs_extra_trb) {
+ unsigned int maxp = usb_endpoint_maxp(dep->endpoint.desc);
+
ret = dwc3_gadget_ep_reclaim_trb_linear(dep, req, event,
status);
+
+ /* Reclaim MPS padding TRB for ZLP */
+ if (!req->direction && req->request.zero && req->request.length &&
+ !usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
+ (IS_ALIGNED(req->request.length, maxp)))
+ ret = dwc3_gadget_ep_reclaim_trb_linear(dep, req, event, status);
+
req->needs_extra_trb = false;
}