pata_atiixp: propogate cable detection hack from drivers/ide to the new driver

diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.20-rc6-mm3/drivers/ata/pata_atiixp.c linux-2.6.20-rc6-mm3/drivers/ata/pata_atiixp.c
@@ -36,15 +36,22 @@
 static int atiixp_pre_reset(struct ata_port *ap)
 {
 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
-	static struct pci_bits atiixp_enable_bits[] = {
+	static const struct pci_bits atiixp_enable_bits[] = {
 		{ 0x48, 1, 0x01, 0x00 },
 		{ 0x48, 1, 0x08, 0x00 }
 	};
+	u8 udma;
 
 	if (!pci_test_config_bits(pdev, &atiixp_enable_bits[ap->port_no]))
 		return -ENOENT;
 
-	ap->cbl = ATA_CBL_PATA80;
+	/* Hack from drivers/ide/pci. Really we want to know how to do the
+	   raw detection not play follow the bios mode guess */
+	pci_read_config_byte(pdev, ATIIXP_IDE_UDMA_MODE + ap->port_no, &udma);
+	if ((udma & 0x07) >= 0x04 || (udma & 0x70) >= 0x40)
+		ap->cbl = ATA_CBL_PATA80;
+	else
+		ap->cbl = ATA_CBL_PATA40;
 	return ata_std_prereset(ap);
 }