usb: dwc2: host: fix the data toggle error in full speed descriptor dma

There will be data toggle error happen for full speed buld-out transfer.
The data toggle bit is saved in qh for non-control transfers, it is wrong
to  check the qtd for that case.

Also fix one static analysis tool issue after fix the data toggle error.

John Youn:
* Added WARN() to warn on improper usage of the
  dwc2_hcd_save_data_toggle() function.

Signed-off-by: Dyson Lee <dyson.lee@intel.com>
Signed-off-by: Tang, Jianqiang <jianqiang.tang@intel.com>
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

2 files changed, 9 insertions, 1 deletions

diff --git a/drivers/usb/dwc2/hcd_ddma.c b/drivers/usb/dwc2/hcd_ddma.c
index 89db47a1ffed..a41274aa52ad 100644
--- a/drivers/usb/dwc2/hcd_ddma.c
+++ b/drivers/usb/dwc2/hcd_ddma.c
@@ -1257,7 +1257,7 @@ stop_scan:
                  */
                 if (halt_status == DWC2_HC_XFER_STALL)
                         qh->data_toggle = DWC2_HC_PID_DATA0;
-                else if (qtd)
+                else
                         dwc2_hcd_save_data_toggle(hsotg, chan, chnum, qtd);
         }
 
diff --git a/drivers/usb/dwc2/hcd_intr.c b/drivers/usb/dwc2/hcd_intr.c
index f8253803a050..cadba8b13c48 100644
--- a/drivers/usb/dwc2/hcd_intr.c
+++ b/drivers/usb/dwc2/hcd_intr.c
@@ -525,11 +525,19 @@ void dwc2_hcd_save_data_toggle(struct dwc2_hsotg *hsotg,
         u32 pid = (hctsiz & TSIZ_SC_MC_PID_MASK) >> TSIZ_SC_MC_PID_SHIFT;
 
         if (chan->ep_type != USB_ENDPOINT_XFER_CONTROL) {
+                if (WARN(!chan || !chan->qh,
+                         "chan->qh must be specified for non-control eps\n"))
+                        return;
+
                 if (pid == TSIZ_SC_MC_PID_DATA0)
                         chan->qh->data_toggle = DWC2_HC_PID_DATA0;
                 else
                         chan->qh->data_toggle = DWC2_HC_PID_DATA1;
         } else {
+                if (WARN(!qtd,
+                         "qtd must be specified for control eps\n"))
+                        return;
+
                 if (pid == TSIZ_SC_MC_PID_DATA0)
                         qtd->data_toggle = DWC2_HC_PID_DATA0;
                 else