[PATCH 1/1] driver,usb: Fix a warning in uhci-hcd driver

Li, Zhen-Hua
2013-04-26T07:39:02Z

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-hual@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