xHCI 1.0: Control endpoint average TRB length field set

xHCI 1.0 specification indicates that software should set Average TRB Length
to '8' for control endpoints.

Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>

1 files changed, 8 insertions, 1 deletions

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index a4fc4d929385..543833b9dbad 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1246,8 +1246,15 @@ int xhci_endpoint_init(struct xhci_hcd *xhci,
          * including link TRBs, No-op TRBs, and Event data TRBs.  Since we don't
          * use Event Data TRBs, and we don't chain in a link TRB on short
          * transfers, we're basically dividing by 1.
+         *
+         * xHCI 1.0 specification indicates that the Average TRB Length should
+         * be set to 8 for control endpoints.
          */
-        ep_ctx->tx_info |= cpu_to_le32(AVG_TRB_LENGTH_FOR_EP(max_esit_payload));
+        if (usb_endpoint_xfer_control(&ep->desc) && xhci->hci_version == 0x100)
+                ep_ctx->tx_info |= cpu_to_le32(AVG_TRB_LENGTH_FOR_EP(8));
+        else
+                ep_ctx->tx_info |=
+                         cpu_to_le32(AVG_TRB_LENGTH_FOR_EP(max_esit_payload));
 
         /* FIXME Debug endpoint context */
         return 0;