usb_canbus: Prioritize local response sending over new host messages

Prioritize sending responses back to the host over transmitting new messages from the host. Otherwise, the gs_usb host usb acknowledgments could saturate the usb bandwidth for extended periods. Signed-off-by: Kevin O'Connor <[email protected]>
Klipper3d · Oct 1, 2023 · c2cc494 · c2cc494
1 parent 7629e52
commit c2cc494
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/src/generic/usb_canbus.c b/src/generic/usb_canbus.c
@@ -244,9 +244,9 @@ usbcan_task(void)
 
         // Send any previous echo frames
         if (host_status) {
-            if (UsbCan.usb_send_busy)
+            if (UsbCan.notify_local || UsbCan.usb_send_busy)
                 // Don't send echo frame until other traffic is sent
-                return;
+                break;
             int ret = usb_send_bulk_in(gs, sizeof(*gs));
             if (ret < 0)
                 return;
@@ -281,6 +281,8 @@ canbus_send(struct canbus_msg *msg)
     int ret = send_frame(msg);
     if (ret < 0)
         goto retry_later;
+    if (UsbCan.notify_local && UsbCan.host_status)
+        canbus_notify_tx();
     UsbCan.notify_local = 0;
     return msg->dlc;
 retry_later: