ahci: jmb361 has only one port

JMB361 has only one port but reports it has two causing longish probe
failure on the second one.  Quirk it.

Reported by Gajo Petrovic in bz 10911.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Gajo Petrovic <gajo01@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 966ab40..29f34d0 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -653,6 +653,14 @@
 		cap &= ~HOST_CAP_PMP;
 	}
 
+	if (pdev->vendor == PCI_VENDOR_ID_JMICRON && pdev->device == 0x2361 &&
+	    port_map != 1) {
+		dev_printk(KERN_INFO, &pdev->dev,
+			   "JMB361 has only one port, port_map 0x%x -> 0x%x\n",
+			   port_map, 1);
+		port_map = 1;
+	}
+
 	/*
 	 * Temporary Marvell 6145 hack: PATA port presence
 	 * is asserted through the standard AHCI port