usb: add pipelining option to usb endpoints

With this patch applied USB drivers can enable pipelining per endpoint.
With pipelining enabled the usb core will continue submitting packets
even when there are still async transfers in flight instead of passing
them on one by one.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

1 files changed, 10 insertions, 1 deletions

diff --git a/hw/usb.c b/hw/usb.c
index fc41d62438..800d912a27 100644
--- a/hw/usb.c
+++ b/hw/usb.c
@@ -323,7 +323,7 @@ int usb_handle_packet(USBDevice *dev, USBPacket *p)
     assert(p->state == USB_PACKET_SETUP);
     assert(p->ep != NULL);
 
-    if (QTAILQ_EMPTY(&p->ep->queue)) {
+    if (QTAILQ_EMPTY(&p->ep->queue) || p->ep->pipeline) {
         ret = usb_process_one(p);
         if (ret == USB_RET_ASYNC) {
             usb_packet_set_state(p, USB_PACKET_ASYNC);
@@ -468,6 +468,7 @@ void usb_ep_init(USBDevice *dev)
     dev->ep_ctl.type = USB_ENDPOINT_XFER_CONTROL;
     dev->ep_ctl.ifnum = 0;
     dev->ep_ctl.dev = dev;
+    dev->ep_ctl.pipeline = false;
     QTAILQ_INIT(&dev->ep_ctl.queue);
     for (ep = 0; ep < USB_MAX_ENDPOINTS; ep++) {
         dev->ep_in[ep].nr = ep + 1;
@@ -480,6 +481,8 @@ void usb_ep_init(USBDevice *dev)
         dev->ep_out[ep].ifnum = 0;
         dev->ep_in[ep].dev = dev;
         dev->ep_out[ep].dev = dev;
+        dev->ep_in[ep].pipeline = false;
+        dev->ep_out[ep].pipeline = false;
         QTAILQ_INIT(&dev->ep_in[ep].queue);
         QTAILQ_INIT(&dev->ep_out[ep].queue);
     }
@@ -593,3 +596,9 @@ int usb_ep_get_max_packet_size(USBDevice *dev, int pid, int ep)
     struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);
     return uep->max_packet_size;
 }
+
+void usb_ep_set_pipeline(USBDevice *dev, int pid, int ep, bool enabled)
+{
+    struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);
+    uep->pipeline = enabled;
+}