usb: xhci-mtk: fix bpkts value of LS/HS periodic eps not behind TT

when a LS or FS device doesn't connect though a HS hub,
the @bPkts field of its periodic endpoint context should
be set to 1.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/host/xhci-mtk-sch.c b/drivers/usb/host/xhci-mtk-sch.c
index c30de7c39f44088e302b257a480a6c7b159ff167..73f763c4f5f591a2c19053083dedf7b6aa252f31 100644 (file)
--- a/drivers/usb/host/xhci-mtk-sch.c
+++ b/drivers/usb/host/xhci-mtk-sch.c
@@ -275,8 +275,9 @@ static bool need_bw_sch(struct usb_host_endpoint *ep,
                return false;
 
        /*
-        * for LS & FS periodic endpoints which its device don't attach
-        * to TT are also ignored, root-hub will schedule them directly
+        * for LS & FS periodic endpoints which its device is not behind
+        * a TT are also ignored, root-hub will schedule them directly,
+        * but need set @bpkts field of endpoint context to 1.
         */
        if (is_fs_or_ls(speed) && !has_tt)
                return false;
@@ -339,8 +340,17 @@ int xhci_mtk_add_ep_quirk(struct usb_hcd *hcd, struct usb_device *udev,
                GET_MAX_PACKET(usb_endpoint_maxp(&ep->desc)),
                usb_endpoint_dir_in(&ep->desc), ep);
 
-       if (!need_bw_sch(ep, udev->speed, slot_ctx->tt_info & TT_SLOT))
+       if (!need_bw_sch(ep, udev->speed, slot_ctx->tt_info & TT_SLOT)) {
+               /*
+                * set @bpkts to 1 if it is LS or FS periodic endpoint, and its
+                * device does not connected through an external HS hub
+                */
+               if (usb_endpoint_xfer_int(&ep->desc)
+                       || usb_endpoint_xfer_isoc(&ep->desc))
+                       ep_ctx->reserved[0] |= cpu_to_le32(EP_BPKTS(1));
+
                return 0;
+       }
 
        bw_index = get_bw_index(xhci, udev, ep);
        sch_bw = &sch_array[bw_index];