1 files changed, 24 insertions, 0 deletions

diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index c46a58f9181d..36864f958444 100644
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -66,6 +66,8 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
 {
         struct ehci_hcd         *ehci = hcd_to_ehci(hcd);
         struct pci_dev          *pdev = to_pci_dev(hcd->self.controller);
+        struct pci_dev          *p_smbus;
+        u8                      rev;
         u32                     temp;
         int                     retval;
 
@@ -166,6 +168,28 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
                         pci_write_config_byte(pdev, 0x4b, tmp | 0x20);
                 }
                 break;
+        case PCI_VENDOR_ID_ATI:
+                /* SB600 and old version of SB700 have a bug in EHCI controller,
+                 * which causes usb devices lose response in some cases.
+                 */
+                if ((pdev->device == 0x4386) || (pdev->device == 0x4396)) {
+                        p_smbus = pci_get_device(PCI_VENDOR_ID_ATI,
+                                                 PCI_DEVICE_ID_ATI_SBX00_SMBUS,
+                                                 NULL);
+                        if (!p_smbus)
+                                break;
+                        rev = p_smbus->revision;
+                        if ((pdev->device == 0x4386) || (rev == 0x3a)
+                            || (rev == 0x3b)) {
+                                u8 tmp;
+                                ehci_info(ehci, "applying AMD SB600/SB700 USB "
+                                        "freeze workaround\n");
+                                pci_read_config_byte(pdev, 0x53, &tmp);
+                                pci_write_config_byte(pdev, 0x53, tmp | (1<<3));
+                        }
+                        pci_dev_put(p_smbus);
+                }
+                break;
         }
 
         ehci_reset(ehci);