usb: xhci: Fix max packet size for full speed device endpoint 0

In xhci_check_maxpacket(), the control endpoint 0 max packet size
is wrongly taken from the interface's endpoint descriptor. However
the default endpoint 0 does not come with an endpoint descriptor
hence is not included in the interface structure. Change to use
epmaxpacketin[0] instead.

The other bug in this routine is that when setting max packet size
to the xHC endpoint 0 context, it does not clear its previous value
at all before programming a new one.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 4b3d58d56e6b0558cb99f71c544c71d905038706..ec82fa664e100a10ae14d04077821506a95281d8 100644 (file)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -546,16 +546,13 @@ int xhci_check_maxpacket(struct usb_device *udev)
        int max_packet_size;
        int hw_max_packet_size;
        int ret = 0;
-       struct usb_interface *ifdesc;
-
-       ifdesc = &udev->config.if_desc[0];
 
        out_ctx = ctrl->devs[slot_id]->out_ctx;
        xhci_inval_cache((uintptr_t)out_ctx->bytes, out_ctx->size);
 
        ep_ctx = xhci_get_ep_ctx(ctrl, out_ctx, ep_index);
        hw_max_packet_size = MAX_PACKET_DECODED(le32_to_cpu(ep_ctx->ep_info2));
-       max_packet_size = usb_endpoint_maxp(&ifdesc->ep_desc[0]);
+       max_packet_size = udev->epmaxpacketin[0];
        if (hw_max_packet_size != max_packet_size) {
                debug("Max Packet Size for ep 0 changed.\n");
                debug("Max packet size in usb_device = %d\n", max_packet_size);
@@ -567,7 +564,8 @@ int xhci_check_maxpacket(struct usb_device *udev)
                                ctrl->devs[slot_id]->out_ctx, ep_index);
                in_ctx = ctrl->devs[slot_id]->in_ctx;
                ep_ctx = xhci_get_ep_ctx(ctrl, in_ctx, ep_index);
-               ep_ctx->ep_info2 &= cpu_to_le32(~MAX_PACKET_MASK);
+               ep_ctx->ep_info2 &= cpu_to_le32(~((0xffff & MAX_PACKET_MASK)
+                                               << MAX_PACKET_SHIFT));
                ep_ctx->ep_info2 |= cpu_to_le32(MAX_PACKET(max_packet_size));
 
                /*