This patch is trying to fix this bug on SLES11 SP2:
    https://bugzilla.novell.com/show_bug.cgi?id=817035

On a large HP system with 64T memory and 60 logical cpus, when usb
driver inits the iLo Virtual USB Controller, there comes a warning
"Controller not stopped yet!". It is because the HP iLo virtual usb
device requires a longer delay.

Signed-off-by: Li, Zhen-Hua <zhen-h...@hp.com>
---
 drivers/usb/host/uhci-hcd.c |    5 +++++
 drivers/usb/host/uhci-hub.c |   12 +++++++-----
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/host/uhci-hcd.c b/drivers/usb/host/uhci-hcd.c
index 4a86b63..af30517 100644
--- a/drivers/usb/host/uhci-hcd.c
+++ b/drivers/usb/host/uhci-hcd.c
@@ -355,6 +355,11 @@ __acquires(uhci->lock)
                if (uhci->dead)
                        return;
        }
+
+       /* HP's iLo Virtual USB Controller requires a longer delay. */
+       if (uhci->wait_for_hp)
+               wait_for_HP(uhci, USBSTS, USBSTS_HCH, 1000);
+
        if (!(uhci_readw(uhci, USBSTS) & USBSTS_HCH))
                dev_warn(uhci_dev(uhci), "Controller not stopped yet!\n");
 
diff --git a/drivers/usb/host/uhci-hub.c b/drivers/usb/host/uhci-hub.c
index f87bee6..c3f772c 100644
--- a/drivers/usb/host/uhci-hub.c
+++ b/drivers/usb/host/uhci-hub.c
@@ -120,14 +120,15 @@ static void uhci_finish_suspend(struct uhci_hcd *uhci, 
int port,
 }
 
 /* Wait for the UHCI controller in HP's iLO2 server management chip.
- * It can take up to 250 us to finish a reset and set the CSC bit.
+ * It can take up to max_wait us to finish the operation.
  */
-static void wait_for_HP(struct uhci_hcd *uhci, unsigned long port_addr)
+static void wait_for_HP(struct uhci_hcd *uhci, unsigned long port_addr,
+               u16 status, int max_wait)
 {
        int i;
 
-       for (i = 10; i < 250; i += 10) {
-               if (uhci_readw(uhci, port_addr) & USBPORTSC_CSC)
+       for (i = 10; i < max_wait; i += 10) {
+               if (uhci_readw(uhci, port_addr) & status)
                        return;
                udelay(10);
        }
@@ -151,7 +152,8 @@ static void uhci_check_ports(struct uhci_hcd *uhci)
                                /* HP's server management chip requires
                                 * a longer delay. */
                                if (uhci->wait_for_hp)
-                                       wait_for_HP(uhci, port_addr);
+                                       wait_for_HP(uhci, port_addr,
+                                               USBPORTSC_CSC, 250);
 
                                /* If the port was enabled before, turning
                                 * reset on caused a port enable change.
-- 
1.7.10.4

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