UHCI: Fix problem caused by lack of terminating QH

This patch (as871) fixes a problem introduced by an earlier change.
It turns out that some systems really do need to have a terminating
skeleton QH present whenever FSBR is on.  I don't know any way to tell
which systems do need it and which don't; the easiest answer is to
have it there always.

This fixes the NumLock-hang bug reported by Jiri Slaby.

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

1 files changed, 15 insertions, 11 deletions

diff --git a/drivers/usb/host/uhci-debug.c b/drivers/usb/host/uhci-debug.c
index 8d24d3dc0a61..1497371583b9 100644
--- a/drivers/usb/host/uhci-debug.c
+++ b/drivers/usb/host/uhci-debug.c
@@ -145,7 +145,8 @@ static int uhci_show_urbp(struct urb_priv *urbp, char *buf, int len, int space)
         return out - buf;
 }
 
-static int uhci_show_qh(struct uhci_qh *qh, char *buf, int len, int space)
+static int uhci_show_qh(struct uhci_hcd *uhci,
+                struct uhci_qh *qh, char *buf, int len, int space)
 {
         char *out = buf;
         int i, nurbs;
@@ -190,6 +191,9 @@ static int uhci_show_qh(struct uhci_qh *qh, char *buf, int len, int space)
 
         if (list_empty(&qh->queue)) {
                 out += sprintf(out, "%*s  queue is empty\n", space, "");
+                if (qh == uhci->skel_async_qh)
+                        out += uhci_show_td(uhci->term_td, out,
+                                        len - (out - buf), 0);
         } else {
                 struct urb_priv *urbp = list_entry(qh->queue.next,
                                 struct urb_priv, node);
@@ -343,6 +347,7 @@ static int uhci_sprint_schedule(struct uhci_hcd *uhci, char *buf, int len)
         struct list_head *tmp, *head;
         int nframes, nerrs;
         __le32 link;
+        __le32 fsbr_link;
 
         static const char * const qh_names[] = {
                 "unlink", "iso", "int128", "int64", "int32", "int16",
@@ -424,21 +429,22 @@ check_link:
 
         out += sprintf(out, "Skeleton QHs\n");
 
+        fsbr_link = 0;
         for (i = 0; i < UHCI_NUM_SKELQH; ++i) {
                 int cnt = 0;
-                __le32 fsbr_link = 0;
 
                 qh = uhci->skelqh[i];
                 out += sprintf(out, "- skel_%s_qh\n", qh_names[i]); \
-                out += uhci_show_qh(qh, out, len - (out - buf), 4);
+                out += uhci_show_qh(uhci, qh, out, len - (out - buf), 4);
 
                 /* Last QH is the Terminating QH, it's different */
                 if (i == SKEL_TERM) {
                         if (qh_element(qh) != LINK_TO_TD(uhci->term_td))
                                 out += sprintf(out, "    skel_term_qh element is not set to term_td!\n");
-                        if (link == LINK_TO_QH(uhci->skel_term_qh))
-                                goto check_qh_link;
-                        continue;
+                        link = fsbr_link;
+                        if (!link)
+                                link = LINK_TO_QH(uhci->skel_term_qh);
+                        goto check_qh_link;
                 }
 
                 head = &qh->node;
@@ -448,7 +454,7 @@ check_link:
                         qh = list_entry(tmp, struct uhci_qh, node);
                         tmp = tmp->next;
                         if (++cnt <= 10)
-                                out += uhci_show_qh(qh, out,
+                                out += uhci_show_qh(uhci, qh, out,
                                                 len - (out - buf), 4);
                         if (!fsbr_link && qh->skel >= SKEL_FSBR)
                                 fsbr_link = LINK_TO_QH(qh);
@@ -463,8 +469,6 @@ check_link:
                         link = LINK_TO_QH(uhci->skel_async_qh);
                 else if (!uhci->fsbr_is_on)
                         ;
-                else if (fsbr_link)
-                        link = fsbr_link;
                 else
                         link = LINK_TO_QH(uhci->skel_term_qh);
 check_qh_link:
@@ -573,8 +577,8 @@ static const struct file_operations uhci_debug_operations = {
 static inline void lprintk(char *buf)
 {}
 
-static inline int uhci_show_qh(struct uhci_qh *qh, char *buf,
-                int len, int space)
+static inline int uhci_show_qh(struct uhci_hcd *uhci,
+                struct uhci_qh *qh, char *buf, int len, int space)
 {
         return 0;
 }