xhci 1.0: Set transfer burst count field.

[pandora-kernel.git] / drivers / usb / host / xhci-ring.c

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 27d690d..cc59632 100644 (file)
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -3123,6 +3123,27 @@ static int count_isoc_trbs_needed(struct xhci_hcd *xhci,
        return num_trbs;
 }
 
+/*
+ * The transfer burst count field of the isochronous TRB defines the number of
+ * bursts that are required to move all packets in this TD.  Only SuperSpeed
+ * devices can burst up to bMaxBurst number of packets per service interval.
+ * This field is zero based, meaning a value of zero in the field means one
+ * burst.  Basically, for everything but SuperSpeed devices, this field will be
+ * zero.  Only xHCI 1.0 host controllers support this field.
+ */
+static unsigned int xhci_get_burst_count(struct xhci_hcd *xhci,
+               struct usb_device *udev,
+               struct urb *urb, unsigned int total_packet_count)
+{
+       unsigned int max_burst;
+
+       if (xhci->hci_version < 0x100 || udev->speed != USB_SPEED_SUPER)
+               return 0;
+
+       max_burst = urb->ep->ss_ep_comp.bMaxBurst;
+       return roundup(total_packet_count, max_burst + 1) - 1;
+}
+
 /* This is for isoc transfer */
 static int xhci_queue_isoc_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
                struct urb *urb, int slot_id, unsigned int ep_index)
@@ -3164,14 +3185,18 @@ static int xhci_queue_isoc_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
        /* Queue the first TRB, even if it's zero-length */
        for (i = 0; i < num_tds; i++) {
                unsigned int total_packet_count;
+               unsigned int burst_count;
 
                first_trb = true;
                running_total = 0;
                addr = start_addr + urb->iso_frame_desc[i].offset;
                td_len = urb->iso_frame_desc[i].length;
                td_remain_len = td_len;
+               /* FIXME: Ignoring zero-length packets, can those happen? */
                total_packet_count = roundup(td_len,
                                le16_to_cpu(urb->ep->desc.wMaxPacketSize));
+               burst_count = xhci_get_burst_count(xhci, urb->dev, urb,
+                               total_packet_count);
 
                trbs_per_td = count_isoc_trbs_needed(xhci, urb, i);
 
@@ -3185,7 +3210,7 @@ static int xhci_queue_isoc_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
 
                for (j = 0; j < trbs_per_td; j++) {
                        u32 remainder = 0;
-                       field = 0;
+                       field = TRB_TBC(burst_count);
 
                        if (first_trb) {
                                /* Queue the isoc TRB */