[PATCH 4.8 14/85] usb: dwc3: gadget: set PCM1 field of isochronous-first TRBs

From: Greg Kroah-Hartman
Date: Wed Jan 04 2017 - 15:52:34 EST


4.8-stable review patch. If anyone has any objections, please let me know.

------------------

From: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>

commit 6b9018d4c1e5c958625be94a160a5984351d4632 upstream.

In case of High-Speed, High-Bandwidth endpoints, we
need to tell DWC3 that we have more than one packet
per interval. We do that by setting PCM1 field of
Isochronous-First TRB.

Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/usb/dwc3/gadget.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -775,6 +775,9 @@ static void dwc3_prepare_one_trb(struct
unsigned length, unsigned last, unsigned chain, unsigned node)
{
struct dwc3_trb *trb;
+ struct dwc3 *dwc = dep->dwc;
+ struct usb_gadget *gadget = &dwc->gadget;
+ enum usb_device_speed speed = gadget->speed;

dwc3_trace(trace_dwc3_gadget, "%s: req %p dma %08llx length %d%s%s",
dep->name, req, (unsigned long long) dma,
@@ -804,10 +807,16 @@ static void dwc3_prepare_one_trb(struct
break;

case USB_ENDPOINT_XFER_ISOC:
- if (!node)
+ if (!node) {
trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS_FIRST;
- else
+
+ if (speed == USB_SPEED_HIGH) {
+ struct usb_ep *ep = &dep->endpoint;
+ trb->size |= DWC3_TRB_SIZE_PCM1(ep->mult - 1);
+ }
+ } else {
trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS;
+ }

/* always enable Interrupt on Missed ISOC */
trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;