xhci: Fix number of streams allocated when using streams

According to the xhci spec the total number of streams is
2 ^ (MaxPStreams + 1), and this is also how the Linux xhci driver
uses this field.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

diff --git a/hw/usb/hcd-xhci.c b/hw/usb/hcd-xhci.c
index f02231dc87eee81903253459746b67c157dce7e0..69d9144ee8154796917f6a3152d4f1719841ea28 100644 (file)
--- a/hw/usb/hcd-xhci.c
+++ b/hw/usb/hcd-xhci.c
@@ -1138,7 +1138,7 @@ static void xhci_reset_streams(XHCIEPContext *epctx)
 static void xhci_alloc_streams(XHCIEPContext *epctx, dma_addr_t base)
 {
     assert(epctx->pstreams == NULL);
-    epctx->nr_pstreams = 2 << epctx->max_pstreams;
+    epctx->nr_pstreams = 2 << (epctx->max_pstreams + 1);
     epctx->pstreams = xhci_alloc_stream_contexts(epctx->nr_pstreams, base);
 }