usb: dwc3: Set the ClearPendIN bit on Clear Stall EP command

As of core revision 2.60a the recommended programming model is to set
the ClearPendIN bit when issuing a Clear Stall EP command for IN
endpoints. This is to prevent an issue where some (non-compliant) hosts
may not send ACK TPs for pending IN transfers due to a mishandled error
condition. Synopsys STAR 9000614252.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 7ddf9449a06302ed7c72bb692ed4e5cc52bd40a5..654050684f4fadb4004587edcb653ca03c0d4f3f 100644 (file)
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -402,6 +402,7 @@
 #define DWC3_DEPCMD_GET_RSC_IDX(x)     (((x) >> DWC3_DEPCMD_PARAM_SHIFT) & 0x7f)
 #define DWC3_DEPCMD_STATUS(x)          (((x) >> 12) & 0x0F)
 #define DWC3_DEPCMD_HIPRI_FORCERM      (1 << 11)
+#define DWC3_DEPCMD_CLEARPENDIN                (1 << 11)
 #define DWC3_DEPCMD_CMDACT             (1 << 10)
 #define DWC3_DEPCMD_CMDIOC             (1 << 8)
 

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 9a7d0bd15dc311c2a697678f05a7cc67ca3ef2ad..07248ff1be5c150b04c2d0f6297290489c94c205 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -347,6 +347,28 @@ int dwc3_send_gadget_ep_cmd(struct dwc3 *dwc, unsigned ep,
        return ret;
 }
 
+static int dwc3_send_clear_stall_ep_cmd(struct dwc3_ep *dep)
+{
+       struct dwc3 *dwc = dep->dwc;
+       struct dwc3_gadget_ep_cmd_params params;
+       u32 cmd = DWC3_DEPCMD_CLEARSTALL;
+
+       /*
+        * As of core revision 2.60a the recommended programming model
+        * is to set the ClearPendIN bit when issuing a Clear Stall EP
+        * command for IN endpoints. This is to prevent an issue where
+        * some (non-compliant) hosts may not send ACK TPs for pending
+        * IN transfers due to a mishandled error condition. Synopsys
+        * STAR 9000614252.
+        */
+       if (dep->direction && (dwc->revision >= DWC3_REVISION_260A))
+               cmd |= DWC3_DEPCMD_CLEARPENDIN;
+
+       memset(&params, 0, sizeof(params));
+
+       return dwc3_send_gadget_ep_cmd(dwc, dep->number, cmd, &params);
+}
+
 static dma_addr_t dwc3_trb_dma_offset(struct dwc3_ep *dep,
                struct dwc3_trb *trb)
 {
@@ -1314,8 +1336,7 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
                else
                        dep->flags |= DWC3_EP_STALL;
        } else {
-               ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
-                       DWC3_DEPCMD_CLEARSTALL, &params);
+               ret = dwc3_send_clear_stall_ep_cmd(dep);
                if (ret)
                        dev_err(dwc->dev, "failed to clear STALL on %s\n",
                                        dep->name);
@@ -2247,7 +2268,6 @@ static void dwc3_clear_stall_all_ep(struct dwc3 *dwc)
 
        for (epnum = 1; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
                struct dwc3_ep *dep;
-               struct dwc3_gadget_ep_cmd_params params;
                int ret;
 
                dep = dwc->eps[epnum];
@@ -2259,9 +2279,7 @@ static void dwc3_clear_stall_all_ep(struct dwc3 *dwc)
 
                dep->flags &= ~DWC3_EP_STALL;
 
-               memset(&params, 0, sizeof(params));
-               ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
-                               DWC3_DEPCMD_CLEARSTALL, &params);
+               ret = dwc3_send_clear_stall_ep_cmd(dep);
                WARN_ON_ONCE(ret);
        }
 }