Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/v4l-dvb

[linux-2.6-omap-h63xx.git] / drivers / usb / host / ehci-sched.c

diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
index be575e46eac3132a661479a9138fcf64ea3a73ae..4a0c5a78b2ed74358055e800d5181b1a1e2cb1c7 100644 (file)
--- a/drivers/usb/host/ehci-sched.c
+++ b/drivers/usb/host/ehci-sched.c
@@ -437,6 +437,9 @@ static int enable_periodic (struct ehci_hcd *ehci)
        u32     cmd;
        int     status;
 
+       if (ehci->periodic_sched++)
+               return 0;
+
        /* did clearing PSE did take effect yet?
         * takes effect only at frame boundaries...
         */
@@ -461,6 +464,9 @@ static int disable_periodic (struct ehci_hcd *ehci)
        u32     cmd;
        int     status;
 
+       if (--ehci->periodic_sched)
+               return 0;
+
        /* did setting PSE not take effect yet?
         * takes effect only at frame boundaries...
         */
@@ -544,13 +550,10 @@ static int qh_link_periodic (struct ehci_hcd *ehci, struct ehci_qh *qh)
                : (qh->usecs * 8);
 
        /* maybe enable periodic schedule processing */
-       if (!ehci->periodic_sched++)
-               return enable_periodic (ehci);
-
-       return 0;
+       return enable_periodic(ehci);
 }
 
-static void qh_unlink_periodic (struct ehci_hcd *ehci, struct ehci_qh *qh)
+static int qh_unlink_periodic(struct ehci_hcd *ehci, struct ehci_qh *qh)
 {
        unsigned        i;
        unsigned        period;
@@ -586,9 +589,7 @@ static void qh_unlink_periodic (struct ehci_hcd *ehci, struct ehci_qh *qh)
        qh_put (qh);
 
        /* maybe turn off periodic schedule */
-       ehci->periodic_sched--;
-       if (!ehci->periodic_sched)
-               (void) disable_periodic (ehci);
+       return disable_periodic(ehci);
 }
 
 static void intr_deschedule (struct ehci_hcd *ehci, struct ehci_qh *qh)
@@ -1349,18 +1350,27 @@ iso_stream_schedule (
        /* when's the last uframe this urb could start? */
        max = now + mod;
 
-       /* typical case: reuse current schedule. stream is still active,
-        * and no gaps from host falling behind (irq delays etc)
+       /* Typical case: reuse current schedule, stream is still active.
+        * Hopefully there are no gaps from the host falling behind
+        * (irq delays etc), but if there are we'll take the next
+        * slot in the schedule, implicitly assuming URB_ISO_ASAP.
         */
        if (likely (!list_empty (&stream->td_list))) {
                start = stream->next_uframe;
                if (start < now)
                        start += mod;
-               if (likely ((start + sched->span) < max))
-                       goto ready;
-               /* else fell behind; someday, try to reschedule */
-               status = -EL2NSYNC;
-               goto fail;
+
+               /* Fell behind (by up to twice the slop amount)? */
+               if (start >= max - 2 * 8 * SCHEDULE_SLOP)
+                       start += stream->interval * DIV_ROUND_UP(
+                                       max - start, stream->interval) - mod;
+
+               /* Tried to schedule too far into the future? */
+               if (unlikely((start + sched->span) >= max)) {
+                       status = -EFBIG;
+                       goto fail;
+               }
+               goto ready;
        }
 
        /* need to schedule; when's the next (u)frame we could start?
@@ -1553,9 +1563,7 @@ itd_link_urb (
        urb->hcpriv = NULL;
 
        timer_action (ehci, TIMER_IO_WATCHDOG);
-       if (unlikely (!ehci->periodic_sched++))
-               return enable_periodic (ehci);
-       return 0;
+       return enable_periodic(ehci);
 }
 
 #define        ISO_ERRS (EHCI_ISOC_BUF_ERR | EHCI_ISOC_BABBLE | EHCI_ISOC_XACTERR)
@@ -1613,6 +1621,9 @@ itd_complete (
                } else if (likely ((t & EHCI_ISOC_ACTIVE) == 0)) {
                        desc->status = 0;
                        desc->actual_length = EHCI_ITD_LENGTH (t);
+               } else {
+                       /* URB was too late */
+                       desc->status = -EXDEV;
                }
        }
 
@@ -1630,7 +1641,7 @@ itd_complete (
        ehci_urb_done(ehci, urb, 0);
        retval = true;
        urb = NULL;
-       ehci->periodic_sched--;
+       (void) disable_periodic(ehci);
        ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs--;
 
        if (unlikely (list_empty (&stream->td_list))) {
@@ -1939,9 +1950,7 @@ sitd_link_urb (
        urb->hcpriv = NULL;
 
        timer_action (ehci, TIMER_IO_WATCHDOG);
-       if (!ehci->periodic_sched++)
-               return enable_periodic (ehci);
-       return 0;
+       return enable_periodic(ehci);
 }
 
 /*-------------------------------------------------------------------------*/
@@ -2007,7 +2016,7 @@ sitd_complete (
        ehci_urb_done(ehci, urb, 0);
        retval = true;
        urb = NULL;
-       ehci->periodic_sched--;
+       (void) disable_periodic(ehci);
        ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs--;
 
        if (list_empty (&stream->td_list)) {
@@ -2095,7 +2104,7 @@ done:
 static void
 scan_periodic (struct ehci_hcd *ehci)
 {
-       unsigned        frame, clock, now_uframe, mod;
+       unsigned        now_uframe, frame, clock, clock_frame, mod;
        unsigned        modified;
 
        mod = ehci->periodic_size << 3;
@@ -2111,6 +2120,7 @@ scan_periodic (struct ehci_hcd *ehci)
        else
                clock = now_uframe + mod - 1;
        clock %= mod;
+       clock_frame = clock >> 3;
 
        for (;;) {
                union ehci_shadow       q, *q_p;
@@ -2157,22 +2167,26 @@ restart:
                        case Q_TYPE_ITD:
                                /* If this ITD is still active, leave it for
                                 * later processing ... check the next entry.
+                                * No need to check for activity unless the
+                                * frame is current.
                                 */
-                               rmb ();
-                               for (uf = 0; uf < 8 && live; uf++) {
-                                       if (0 == (q.itd->hw_transaction [uf]
-                                                       & ITD_ACTIVE(ehci)))
-                                               continue;
-                                       incomplete = true;
-                                       q_p = &q.itd->itd_next;
-                                       hw_p = &q.itd->hw_next;
-                                       type = Q_NEXT_TYPE(ehci,
+                               if (frame == clock_frame && live) {
+                                       rmb();
+                                       for (uf = 0; uf < 8; uf++) {
+                                               if (q.itd->hw_transaction[uf] &
+                                                           ITD_ACTIVE(ehci))
+                                                       break;
+                                       }
+                                       if (uf < 8) {
+                                               incomplete = true;
+                                               q_p = &q.itd->itd_next;
+                                               hw_p = &q.itd->hw_next;
+                                               type = Q_NEXT_TYPE(ehci,
                                                        q.itd->hw_next);
-                                       q = *q_p;
-                                       break;
+                                               q = *q_p;
+                                               break;
+                                       }
                                }
-                               if (uf < 8 && live)
-                                       break;
 
                                /* Take finished ITDs out of the schedule
                                 * and process them:  recycle, maybe report
@@ -2189,9 +2203,12 @@ restart:
                        case Q_TYPE_SITD:
                                /* If this SITD is still active, leave it for
                                 * later processing ... check the next entry.
+                                * No need to check for activity unless the
+                                * frame is current.
                                 */
-                               if ((q.sitd->hw_results & SITD_ACTIVE(ehci))
-                                               && live) {
+                               if (frame == clock_frame && live &&
+                                               (q.sitd->hw_results &
+                                                       SITD_ACTIVE(ehci))) {
                                        incomplete = true;
                                        q_p = &q.sitd->sitd_next;
                                        hw_p = &q.sitd->hw_next;
@@ -2223,8 +2240,7 @@ restart:
                        if (unlikely (modified)) {
                                if (likely(ehci->periodic_sched > 0))
                                        goto restart;
-                               /* maybe we can short-circuit this scan! */
-                               disable_periodic(ehci);
+                               /* short-circuit this scan */
                                now_uframe = clock;
                                break;
                        }
@@ -2260,6 +2276,7 @@ restart:
 
                        /* rescan the rest of this frame, then ... */
                        clock = now;
+                       clock_frame = clock >> 3;
                } else {
                        now_uframe++;
                        now_uframe %= mod;