From 55168470835688e5da5828cdcf1b1498d7baadb1 Mon Sep 17 00:00:00 2001
From: Felipe Balbi <felipe.balbi@linux.intel.com>
Date: Mon, 11 Sep 2017 10:45:12 +0300
Subject: [PATCH] usb: dwc3: ep0: fix DMA starvation by assigning req->trb on
ep0
Git-commit: 55168470835688e5da5828cdcf1b1498d7baadb1
Patch-mainline: v4.14-rc4
References: bsc#1085536
If we don't assign a TRB to ep0 requests, we won't be able to unmap
the request later on resulting in starvation of DMA resources.
Fixes: 4a71fcb8ac5f ("usb: dwc3: gadget: only unmap requests from DMA if mapped")
Reported-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Tested-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
drivers/usb/dwc3/ep0.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 827e376bfa97..75e6cb044eb2 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -990,6 +990,8 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
DWC3_TRBCTL_CONTROL_DATA,
true);
+ req->trb = &dwc->ep0_trb[dep->trb_enqueue - 1];
+
/* Now prepare one extra TRB to align transfer size */
dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr,
maxpacket - rem,
@@ -1015,6 +1017,8 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
DWC3_TRBCTL_CONTROL_DATA,
true);
+ req->trb = &dwc->ep0_trb[dep->trb_enqueue - 1];
+
/* Now prepare one extra TRB to align transfer size */
dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr,
0, DWC3_TRBCTL_CONTROL_DATA,
@@ -1029,6 +1033,9 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
dwc3_ep0_prepare_one_trb(dep, req->request.dma,
req->request.length, DWC3_TRBCTL_CONTROL_DATA,
false);
+
+ req->trb = &dwc->ep0_trb[dep->trb_enqueue];
+
ret = dwc3_ep0_start_trans(dep);
}
--
2.13.6