USB: ohci: quirk AMD prefetch for USB 1.1 ISO transfer

[safe/jmp/linux-2.6] / drivers / usb / host / ohci-pci.c

diff --git a/drivers/usb/host/ohci-pci.c b/drivers/usb/host/ohci-pci.c
index d2ba04d..b8a1148 100644 (file)
--- a/drivers/usb/host/ohci-pci.c
+++ b/drivers/usb/host/ohci-pci.c
@@ -177,6 +177,13 @@ static int ohci_quirk_amd700(struct usb_hcd *hcd)
                return 0;
 
        pci_read_config_byte(amd_smbus_dev, PCI_REVISION_ID, &rev);
+
+       /* SB800 needs pre-fetch fix */
+       if ((rev >= 0x40) && (rev <= 0x4f)) {
+               ohci->flags |= OHCI_QUIRK_AMD_PREFETCH;
+               ohci_dbg(ohci, "enabled AMD prefetch quirk\n");
+       }
+
        if ((rev > 0x3b) || (rev < 0x30)) {
                pci_dev_put(amd_smbus_dev);
                amd_smbus_dev = NULL;
@@ -262,6 +269,19 @@ static void amd_iso_dev_put(void)
 
 }
 
+static void sb800_prefetch(struct ohci_hcd *ohci, int on)
+{
+       struct pci_dev *pdev;
+       u16 misc;
+
+       pdev = to_pci_dev(ohci_to_hcd(ohci)->self.controller);
+       pci_read_config_word(pdev, 0x50, &misc);
+       if (on == 0)
+               pci_write_config_word(pdev, 0x50, misc & 0xfcff);
+       else
+               pci_write_config_word(pdev, 0x50, misc | 0x0300);
+}
+
 /* List of quirks for OHCI */
 static const struct pci_device_id ohci_pci_quirks[] = {
        {