From 83e890a1f63baee491247fc447f61a3bcd9fefa7 Mon Sep 17 00:00:00 2001
From: Alan <alan@lxorguk.ukuu.org.uk>
Date: Mon, 8 Jan 2007 12:10:05 +0000
Subject: [PATCH] --- yaml --- r: 47343 b: refs/heads/master c:
 4112e16a7c606a80810d22d55bfc742eaa61fecb h: refs/heads/master i:   47341:
 95a45023573165c7048337f78091d1ac2e9a176d   47339:
 89d5701d21b072d3708eaa6ffc955c8d03f33e00   47335:
 e0b779735d098a7f75c0b18ea357c9b612927aa6   47327:
 7980b788c3330fd512d11fd801b1004558ea8ada v: v3

---
 [refs]                         |  2 +-
 trunk/drivers/ata/libata-sff.c | 22 ++++++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 06232f417cc9..9053da36c048 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d73f30e1c9a9af14757fa5bf4014343926047156
+refs/heads/master: 4112e16a7c606a80810d22d55bfc742eaa61fecb
diff --git a/trunk/drivers/ata/libata-sff.c b/trunk/drivers/ata/libata-sff.c
index 12c88c588039..cfa9ed179d9c 100644
--- a/trunk/drivers/ata/libata-sff.c
+++ b/trunk/drivers/ata/libata-sff.c
@@ -832,6 +832,21 @@ void ata_bmdma_post_internal_cmd(struct ata_queued_cmd *qc)
 }
 
 #ifdef CONFIG_PCI
+
+static int ata_resources_present(struct pci_dev *pdev, int port)
+{
+	int i;
+	
+	/* Check the PCI resources for this channel are enabled */
+	port = port * 2;
+	for (i = 0; i < 2; i ++) {
+		if (pci_resource_start(pdev, port + i) == 0 ||
+			pci_resource_len(pdev, port + i) == 0)
+		return 0;
+	}
+	return 1;
+}
+		
 /**
  *	ata_pci_init_native_mode - Initialize native-mode driver
  *	@pdev:  pci device to be initialized
@@ -863,6 +878,13 @@ ata_pci_init_native_mode(struct pci_dev *pdev, struct ata_port_info **port, int
 
 	probe_ent->irq = pdev->irq;
 	probe_ent->irq_flags = IRQF_SHARED;
+	
+	/* Discard disabled ports. Some controllers show their
+	   unused channels this way */
+	if (ata_resources_present(pdev, 0) == 0)
+		ports &= ~ATA_PORT_PRIMARY;
+	if (ata_resources_present(pdev, 1) == 0)
+		ports &= ~ATA_PORT_SECONDARY;
 
 	if (ports & ATA_PORT_PRIMARY) {
 		probe_ent->port[p].cmd_addr = pci_resource_start(pdev, 0);