[PATCH] UHCI: remove ISO TDs as they are used

This patch (as690) does the same thing for ISO TDs as as680 did for
non-ISO TDs: free them as they are used rather than all at once when an
URB is complete.  At the same time it fixes a minor buglet (I'm not
aware of it ever affecting anyone): An ISO TD should be retired when its
frame is over, regardless of whether or not the hardware has marked it
inactive.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 73 insertions, 30 deletions

diff --git a/drivers/usb/host/uhci-q.c b/drivers/usb/host/uhci-q.c
index 7acc23473c63..cbbaa4c1740f 100644
--- a/drivers/usb/host/uhci-q.c
+++ b/drivers/usb/host/uhci-q.c
@@ -184,6 +184,24 @@ static inline void uhci_remove_td_from_frame_list(struct uhci_hcd *uhci,
         td->frame = -1;
 }
 
+static inline void uhci_remove_tds_from_frame(struct uhci_hcd *uhci,
+                unsigned int framenum)
+{
+        struct uhci_td *ftd, *ltd;
+
+        framenum &= (UHCI_NUMFRAMES - 1);
+
+        ftd = uhci->frame_cpu[framenum];
+        if (ftd) {
+                ltd = list_entry(ftd->fl_list.prev, struct uhci_td, fl_list);
+                uhci->frame[framenum] = ltd->link;
+                uhci->frame_cpu[framenum] = NULL;
+
+                while (!list_empty(&ftd->fl_list))
+                        list_del_init(ftd->fl_list.prev);
+        }
+}
+
 /*
  * Remove all the TDs for an Isochronous URB from the frame list
  */
@@ -523,7 +541,6 @@ static int uhci_map_status(int status, int dir_out)
                 return -ENOSR;
         if (status & TD_CTRL_STALLED)                   /* Stalled */
                 return -EPIPE;
-        WARN_ON(status & TD_CTRL_ACTIVE);               /* Active */
         return 0;
 }
 
@@ -960,12 +977,12 @@ static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb,
                 return -EFBIG;
 
         /* Check the period and figure out the starting frame number */
-        uhci_get_current_frame_number(uhci);
         if (qh->period == 0) {
                 if (urb->transfer_flags & URB_ISO_ASAP) {
+                        uhci_get_current_frame_number(uhci);
                         urb->start_frame = uhci->frame_number + 10;
                 } else {
-                        i = urb->start_frame - uhci->frame_number;
+                        i = urb->start_frame - uhci->last_iso_frame;
                         if (i <= 0 || i >= UHCI_NUMFRAMES)
                                 return -EINVAL;
                 }
@@ -974,7 +991,7 @@ static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb,
 
         } else {        /* Pick up where the last URB leaves off */
                 if (list_empty(&qh->queue)) {
-                        frame = uhci->frame_number + 10;
+                        frame = qh->iso_frame;
                 } else {
                         struct urb *lurb;
 
@@ -986,11 +1003,12 @@ static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb,
                 }
                 if (urb->transfer_flags & URB_ISO_ASAP)
                         urb->start_frame = frame;
-                /* FIXME: Sanity check */
+                else if (urb->start_frame != frame)
+                        return -EINVAL;
         }
 
         /* Make sure we won't have to go too far into the future */
-        if (uhci_frame_before_eq(uhci->frame_number + UHCI_NUMFRAMES,
+        if (uhci_frame_before_eq(uhci->last_iso_frame + UHCI_NUMFRAMES,
                         urb->start_frame + urb->number_of_packets *
                                 urb->interval))
                 return -EFBIG;
@@ -1020,7 +1038,13 @@ static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb,
         frame = urb->start_frame;
         list_for_each_entry(td, &urbp->td_list, list) {
                 uhci_insert_td_in_frame_list(uhci, td, frame);
-                frame += urb->interval;
+                frame += qh->period;
+        }
+
+        if (list_empty(&qh->queue)) {
+                qh->iso_packet_desc = &urb->iso_frame_desc[0];
+                qh->iso_frame = urb->start_frame;
+                qh->iso_status = 0;
         }
 
         return 0;
@@ -1028,37 +1052,44 @@ static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb,
 
 static int uhci_result_isochronous(struct uhci_hcd *uhci, struct urb *urb)
 {
-        struct uhci_td *td;
-        struct urb_priv *urbp = (struct urb_priv *)urb->hcpriv;
-        int status;
-        int i, ret = 0;
-
-        urb->actual_length = urb->error_count = 0;
+        struct uhci_td *td, *tmp;
+        struct urb_priv *urbp = urb->hcpriv;
+        struct uhci_qh *qh = urbp->qh;
 
-        i = 0;
-        list_for_each_entry(td, &urbp->td_list, list) {
+        list_for_each_entry_safe(td, tmp, &urbp->td_list, list) {
+                unsigned int ctrlstat;
+                int status;
                 int actlength;
-                unsigned int ctrlstat = td_status(td);
 
-                if (ctrlstat & TD_CTRL_ACTIVE)
+                if (uhci_frame_before_eq(uhci->cur_iso_frame, qh->iso_frame))
                         return -EINPROGRESS;
 
-                actlength = uhci_actual_length(ctrlstat);
-                urb->iso_frame_desc[i].actual_length = actlength;
-                urb->actual_length += actlength;
+                uhci_remove_tds_from_frame(uhci, qh->iso_frame);
+
+                ctrlstat = td_status(td);
+                if (ctrlstat & TD_CTRL_ACTIVE) {
+                        status = -EXDEV;        /* TD was added too late? */
+                } else {
+                        status = uhci_map_status(uhci_status_bits(ctrlstat),
+                                        usb_pipeout(urb->pipe));
+                        actlength = uhci_actual_length(ctrlstat);
+
+                        urb->actual_length += actlength;
+                        qh->iso_packet_desc->actual_length = actlength;
+                        qh->iso_packet_desc->status = status;
+                }
 
-                status = uhci_map_status(uhci_status_bits(ctrlstat),
-                                usb_pipeout(urb->pipe));
-                urb->iso_frame_desc[i].status = status;
                 if (status) {
                         urb->error_count++;
-                        ret = status;
+                        qh->iso_status = status;
                 }
 
-                i++;
+                uhci_remove_td_from_urbp(td);
+                uhci_free_td(uhci, td);
+                qh->iso_frame += qh->period;
+                ++qh->iso_packet_desc;
         }
-
-        return ret;
+        return qh->iso_status;
 }
 
 static int uhci_urb_enqueue(struct usb_hcd *hcd,
@@ -1119,6 +1150,7 @@ static int uhci_urb_enqueue(struct usb_hcd *hcd,
                 }
                 break;
         case USB_ENDPOINT_XFER_ISOC:
+                urb->error_count = 0;
                 bustime = usb_check_bandwidth(urb->dev, urb);
                 if (bustime < 0) {
                         ret = bustime;
@@ -1200,9 +1232,18 @@ __acquires(uhci->lock)
 {
         struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv;
 
-        /* Isochronous TDs get unlinked directly from the frame list */
-        if (qh->type == USB_ENDPOINT_XFER_ISOC)
-                uhci_unlink_isochronous_tds(uhci, urb);
+        /* When giving back the first URB in an Isochronous queue,
+         * reinitialize the QH's iso-related members for the next URB. */
+        if (qh->type == USB_ENDPOINT_XFER_ISOC &&
+                        urbp->node.prev == &qh->queue &&
+                        urbp->node.next != &qh->queue) {
+                struct urb *nurb = list_entry(urbp->node.next,
+                                struct urb_priv, node)->urb;
+
+                qh->iso_packet_desc = &nurb->iso_frame_desc[0];
+                qh->iso_frame = nurb->start_frame;
+                qh->iso_status = 0;
+        }
 
         /* Take the URB off the QH's queue.  If the queue is now empty,
          * this is a perfect time for a toggle fixup. */
@@ -1434,6 +1475,7 @@ rescan:
 
         uhci_clear_next_interrupt(uhci);
         uhci_get_current_frame_number(uhci);
+        uhci->cur_iso_frame = uhci->frame_number;
 
         /* Go through all the QH queues and process the URBs in each one */
         for (i = 0; i < UHCI_NUM_SKELQH - 1; ++i) {
@@ -1451,6 +1493,7 @@ rescan:
                 }
         }
 
+        uhci->last_iso_frame = uhci->cur_iso_frame;
         if (uhci->need_rescan)
                 goto rescan;
         uhci->scan_in_progress = 0;