[PATCH] USB: UHCI: Increase port-reset completion delay for HP controllers

This patch (as657) increases the port-reset completion delay in uhci-hcd
for HP's embedded controllers.  Unlike other UHCI controllers, the HP
chips can take as long as 250 us to carry out the processing associated
with finishing a port reset.

This fixes Novell bug #148761.

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

1 files changed, 21 insertions, 0 deletions

diff --git a/drivers/usb/host/uhci-hub.c b/drivers/usb/host/uhci-hub.c
index a71e48a6680..152971d1676 100644
--- a/drivers/usb/host/uhci-hub.c
+++ b/drivers/usb/host/uhci-hub.c
@@ -99,6 +99,21 @@ 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.
+ */
+static void wait_for_HP(unsigned long port_addr)
+{
+        int i;
+
+        for (i = 10; i < 250; i += 10) {
+                if (inw(port_addr) & USBPORTSC_CSC)
+                        return;
+                udelay(10);
+        }
+        /* Log a warning? */
+}
+
 static void uhci_check_ports(struct uhci_hcd *uhci)
 {
         unsigned int port;
@@ -113,6 +128,12 @@ static void uhci_check_ports(struct uhci_hcd *uhci)
                                 CLR_RH_PORTSTAT(USBPORTSC_PR);
                                 udelay(10);
 
+                                /* HP's server management chip requires
+                                 * a longer delay. */
+                                if (to_pci_dev(uhci_dev(uhci))->vendor ==
+                                                PCI_VENDOR_ID_HP)
+                                        wait_for_HP(port_addr);
+
                                 /* If the port was enabled before, turning
                                  * reset on caused a port enable change.
                                  * Turning reset off causes a port connect