2020-04-23 22:11:42

by John Stultz

[permalink] [raw]
Subject: [PATCH] dwc3: Remove check for HWO flag in dwc3_gadget_ep_reclaim_trb_sg()

The check for the HWO flag in dwc3_gadget_ep_reclaim_trb_sg()
causes us to break out of the loop before we call
dwc3_gadget_ep_reclaim_completed_trb(), which is what likely
should be clearing the HWO flag.

This can cause odd behavior where we never reclaim all the trbs
in the sg list, so we never call giveback on a usb req, and that
will causes transfer stalls.

This effectively resovles the adb stalls seen on HiKey960
after userland changes started only using AIO in adbd.

Cc: YongQin Liu <[email protected]>
Cc: Anurag Kumar Vulisha <[email protected]>
Cc: Yang Fei <[email protected]>
Cc: Thinh Nguyen <[email protected]>
Cc: Tejas Joglekar <[email protected]>
Cc: Andrzej Pietrasiewicz <[email protected]>
Cc: Jack Pham <[email protected]>
Cc: Josh Gao <[email protected]>
Cc: Todd Kjos <[email protected]>
Cc: Felipe Balbi <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: [email protected]
Cc: [email protected] #4.20+
Signed-off-by: John Stultz <[email protected]>
---
drivers/usb/dwc3/gadget.c | 3 ---
1 file changed, 3 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 4d3c79d90a6e..2a26d33520ce 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2457,9 +2457,6 @@ static int dwc3_gadget_ep_reclaim_trb_sg(struct dwc3_ep *dep,
for_each_sg(sg, s, pending, i) {
trb = &dep->trb_pool[dep->trb_dequeue];

- if (trb->ctrl & DWC3_TRB_CTRL_HWO)
- break;
-
req->sg = sg_next(s);
req->num_pending_sgs--;

--
2.17.1