usb: dwc3: gadget: Report isoc transfer frame number

Implement the new frame_number API to report the isochronous interval
frame number. This patch checks and reports the interval in which the
isoc transfer was transmitted or received via the Isoc-First TRB SOF
number field.

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

2 files changed, 14 insertions, 0 deletions

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 15c07b2b5866..df876418cb78 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -784,6 +784,7 @@ enum dwc3_link_state {
 #define DWC3_TRB_CTRL_ISP_IMI           BIT(10)
 #define DWC3_TRB_CTRL_IOC               BIT(11)
 #define DWC3_TRB_CTRL_SID_SOFN(n)       (((n) & 0xffff) << 14)
+#define DWC3_TRB_CTRL_GET_SID_SOFN(n)   (((n) & (0xffff << 14)) >> 14)
 
 #define DWC3_TRBCTL_TYPE(n)             ((n) & (0x3f << 4))
 #define DWC3_TRBCTL_NORMAL              DWC3_TRB_CTRL_TRBCTL(1)
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 38d6df98e9ce..e2caf9eec30a 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2340,6 +2340,19 @@ static int dwc3_gadget_ep_reclaim_completed_trb(struct dwc3_ep *dep,
                 trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
 
         /*
+         * For isochronous transfers, the first TRB in a service interval must
+         * have the Isoc-First type. Track and report its interval frame number.
+         */
+        if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
+            (trb->ctrl & DWC3_TRBCTL_ISOCHRONOUS_FIRST)) {
+                unsigned int frame_number;
+
+                frame_number = DWC3_TRB_CTRL_GET_SID_SOFN(trb->ctrl);
+                frame_number &= ~(dep->interval - 1);
+                req->request.frame_number = frame_number;
+        }
+
+        /*
          * If we're dealing with unaligned size OUT transfer, we will be left
          * with one TRB pending in the ring. We need to manually clear HWO bit
          * from that TRB.