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authorPaul Zimmerman <paulz@synopsys.com>2012-02-15 13:35:06 +0200
committerFelipe Balbi <balbi@ti.com>2012-03-02 12:12:03 +0200
commit8d62cd65d74d0e241b3a152f7347bb66126b705b (patch)
tree91c5d44b0ea7080267b54e4503dd44f0a41aa0bf /drivers/usb/dwc3
parent075cd14d2a8d35afc39ad28fc7b968275881266b (diff)
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usb: dwc3: gadget: don't wrap around the TRB poll on non-ISOC
If we have a non-ISOC endpoint, we will not have a Link TRB pointing to the beginning of the TRB pool. On such endpoints, we don't want to let the driver wrap around the TRB pool otherwise controller will hang waiting for a valid TRB. Cc: stable@vger.kernel.org Signed-off-by: Paul Zimmerman <paulz@synopsys.com> Signed-off-by: Felipe Balbi <balbi@ti.com>
Diffstat (limited to 'drivers/usb/dwc3')
-rw-r--r--drivers/usb/dwc3/gadget.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index d121e73d89ae..48b2d0d14481 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -826,6 +826,7 @@ static void dwc3_prepare_trbs(struct dwc3_ep *dep, bool starting)
{
struct dwc3_request *req, *n;
u32 trbs_left;
+ u32 max;
unsigned int last_one = 0;
BUILD_BUG_ON_NOT_POWER_OF_2(DWC3_TRB_NUM);
@@ -833,6 +834,13 @@ static void dwc3_prepare_trbs(struct dwc3_ep *dep, bool starting)
/* the first request must not be queued */
trbs_left = (dep->busy_slot - dep->free_slot) & DWC3_TRB_MASK;
+ /* Can't wrap around on a non-isoc EP since there's no link TRB */
+ if (!usb_endpoint_xfer_isoc(dep->desc)) {
+ max = DWC3_TRB_NUM - (dep->free_slot & DWC3_TRB_MASK);
+ if (trbs_left > max)
+ trbs_left = max;
+ }
+
/*
* If busy & slot are equal than it is either full or empty. If we are
* starting to process requests then we are empty. Otherwise we are