1 files changed, 25 insertions, 0 deletions

diff --git a/drivers/usb/host/ohci-ppc-of.c b/drivers/usb/host/ohci-ppc-of.c
index 7ac53264ead3..68a301710297 100644
--- a/drivers/usb/host/ohci-ppc-of.c
+++ b/drivers/usb/host/ohci-ppc-of.c
@@ -91,6 +91,7 @@ ohci_hcd_ppc_of_probe(struct of_device *op, const struct of_device_id *match)
 
         int rv;
         int is_bigendian;
+        struct device_node *np;
 
         if (usb_disabled())
                 return -ENODEV;
@@ -147,6 +148,30 @@ ohci_hcd_ppc_of_probe(struct of_device *op, const struct of_device_id *match)
         if (rv == 0)
                 return 0;
 
+        /* by now, 440epx is known to show usb_23 erratum */
+        np = of_find_compatible_node(NULL, NULL, "ibm,usb-ehci-440epx");
+
+        /* Work around - At this point ohci_run has executed, the
+        * controller is running, everything, the root ports, etc., is
+        * set up.  If the ehci driver is loaded, put the ohci core in
+        * the suspended state.  The ehci driver will bring it out of
+        * suspended state when / if a non-high speed USB device is
+        * attached to the USB Host port.  If the ehci driver is not
+        * loaded, do nothing. request_mem_region is used to test if
+        * the ehci driver is loaded.
+        */
+        if (np !=  NULL) {
+                if (!of_address_to_resource(np, 0, &res)) {
+                        if (!request_mem_region(res.start, 0x4, hcd_name)) {
+                                writel_be((readl_be(&ohci->regs->control) |
+                                        OHCI_USB_SUSPEND), &ohci->regs->control);
+                                        (void) readl_be(&ohci->regs->control);
+                        } else
+                                release_mem_region(res.start, 0x4);
+                } else
+                    pr_debug(__FILE__ ": cannot get ehci offset from fdt\n");
+        }
+
         iounmap(hcd->regs);
 err_ioremap:
         irq_dispose_mapping(irq);