2 files changed, 35 insertions, 2 deletions

diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c
index aba8f19eae4d..46987735a2e3 100644
--- a/drivers/usb/host/ohci-hcd.c
+++ b/drivers/usb/host/ohci-hcd.c
@@ -72,7 +72,7 @@
 static const char       hcd_name [] = "ohci_hcd";
 
 #define STATECHANGE_DELAY       msecs_to_jiffies(300)
-#define IO_WATCHDOG_DELAY       msecs_to_jiffies(250)
+#define IO_WATCHDOG_DELAY       msecs_to_jiffies(250)
 
 #include "ohci.h"
 #include "pci-quirks.h"
@@ -230,9 +230,11 @@ static int ohci_urb_enqueue (
 
                 /* Start up the I/O watchdog timer, if it's not running */
                 if (!timer_pending(&ohci->io_watchdog) &&
-                                list_empty(&ohci->eds_in_use))
+                                list_empty(&ohci->eds_in_use)) {
+                        ohci->prev_frame_no = ohci_frame_no(ohci);
                         mod_timer(&ohci->io_watchdog,
                                         jiffies + IO_WATCHDOG_DELAY);
+                }
                 list_add(&ed->in_use_list, &ohci->eds_in_use);
 
                 if (ed->type == PIPE_ISOCHRONOUS) {
@@ -727,6 +729,7 @@ static void io_watchdog_func(unsigned long _ohci)
         u32             head;
         struct ed       *ed;
         struct td       *td, *td_start, *td_next;
+        unsigned        frame_no;
         unsigned long   flags;
 
         spin_lock_irqsave(&ohci->lock, flags);
@@ -742,6 +745,7 @@ static void io_watchdog_func(unsigned long _ohci)
         if (!(status & OHCI_INTR_WDH) && ohci->wdh_cnt == ohci->prev_wdh_cnt) {
                 if (ohci->prev_donehead) {
                         ohci_err(ohci, "HcDoneHead not written back; disabled\n");
+ died:
                         usb_hc_died(ohci_to_hcd(ohci));
                         ohci_dump(ohci);
                         ohci_shutdown(ohci_to_hcd(ohci));
@@ -802,7 +806,35 @@ static void io_watchdog_func(unsigned long _ohci)
         ohci_work(ohci);
 
         if (ohci->rh_state == OHCI_RH_RUNNING) {
+
+                /*
+                 * Sometimes a controller just stops working.  We can tell
+                 * by checking that the frame counter has advanced since
+                 * the last time we ran.
+                 *
+                 * But be careful: Some controllers violate the spec by
+                 * stopping their frame counter when no ports are active.
+                 */
+                frame_no = ohci_frame_no(ohci);
+                if (frame_no == ohci->prev_frame_no) {
+                        int             active_cnt = 0;
+                        int             i;
+                        unsigned        tmp;
+
+                        for (i = 0; i < ohci->num_ports; ++i) {
+                                tmp = roothub_portstatus(ohci, i);
+                                /* Enabled and not suspended? */
+                                if ((tmp & RH_PS_PES) && !(tmp & RH_PS_PSS))
+                                        ++active_cnt;
+                        }
+
+                        if (active_cnt > 0) {
+                                ohci_err(ohci, "frame counter not updating; disabled\n");
+                                goto died;
+                        }
+                }
                 if (!list_empty(&ohci->eds_in_use)) {
+                        ohci->prev_frame_no = frame_no;
                         ohci->prev_wdh_cnt = ohci->wdh_cnt;
                         ohci->prev_donehead = ohci_readl(ohci,
                                         &ohci->regs->donehead);
diff --git a/drivers/usb/host/ohci.h b/drivers/usb/host/ohci.h
index 0548f5ca18e2..59f424567a8d 100644
--- a/drivers/usb/host/ohci.h
+++ b/drivers/usb/host/ohci.h
@@ -421,6 +421,7 @@ struct ohci_hcd {
 
         // there are also chip quirks/bugs in init logic
 
+        unsigned                prev_frame_no;
         unsigned                wdh_cnt, prev_wdh_cnt;
         u32                     prev_donehead;
         struct timer_list       io_watchdog;