1 files changed, 22 insertions, 4 deletions

diff --git a/drivers/scsi/libata-bmdma.c b/drivers/scsi/libata-bmdma.c
index 95d81d86d8b..835dff0bafd 100644
--- a/drivers/scsi/libata-bmdma.c
+++ b/drivers/scsi/libata-bmdma.c
@@ -703,6 +703,7 @@ ata_pci_init_native_mode(struct pci_dev *pdev, struct ata_port_info **port, int
         struct ata_probe_ent *probe_ent =
                 ata_probe_ent_alloc(pci_dev_to_dev(pdev), port[0]);
         int p = 0;
+        unsigned long bmdma;
 
         if (!probe_ent)
                 return NULL;
@@ -716,7 +717,12 @@ ata_pci_init_native_mode(struct pci_dev *pdev, struct ata_port_info **port, int
                 probe_ent->port[p].altstatus_addr =
                 probe_ent->port[p].ctl_addr =
                         pci_resource_start(pdev, 1) | ATA_PCI_CTL_OFS;
-                probe_ent->port[p].bmdma_addr = pci_resource_start(pdev, 4);
+                bmdma = pci_resource_start(pdev, 4);
+                if (bmdma) {
+                        if (inb(bmdma + 2) & 0x80)
+                                probe_ent->host_set_flags |= ATA_HOST_SIMPLEX;
+                        probe_ent->port[p].bmdma_addr = bmdma;
+                }
                 ata_std_ports(&probe_ent->port[p]);
                 p++;
         }
@@ -726,7 +732,13 @@ ata_pci_init_native_mode(struct pci_dev *pdev, struct ata_port_info **port, int
                 probe_ent->port[p].altstatus_addr =
                 probe_ent->port[p].ctl_addr =
                         pci_resource_start(pdev, 3) | ATA_PCI_CTL_OFS;
-                probe_ent->port[p].bmdma_addr = pci_resource_start(pdev, 4) + 8;
+                bmdma = pci_resource_start(pdev, 4);
+                if (bmdma) {
+                        bmdma += 8;
+                        if(inb(bmdma + 2) & 0x80)
+                        probe_ent->host_set_flags |= ATA_HOST_SIMPLEX;
+                        probe_ent->port[p].bmdma_addr = bmdma;
+                }
                 ata_std_ports(&probe_ent->port[p]);
                 p++;
         }
@@ -740,6 +752,7 @@ static struct ata_probe_ent *ata_pci_init_legacy_port(struct pci_dev *pdev,
                                 struct ata_port_info *port, int port_num)
 {
         struct ata_probe_ent *probe_ent;
+        unsigned long bmdma;
 
         probe_ent = ata_probe_ent_alloc(pci_dev_to_dev(pdev), port);
         if (!probe_ent)
@@ -766,8 +779,13 @@ static struct ata_probe_ent *ata_pci_init_legacy_port(struct pci_dev *pdev,
                         break;
         }
 
-        probe_ent->port[0].bmdma_addr =
-                pci_resource_start(pdev, 4) + 8 * port_num;
+        bmdma = pci_resource_start(pdev, 4);
+        if (bmdma != 0) {
+                bmdma += 8 * port_num;
+                probe_ent->port[0].bmdma_addr = bmdma;
+                if (inb(bmdma + 2) & 0x80)
+                        probe_ent->host_set_flags |= ATA_HOST_SIMPLEX;
+        }
         ata_std_ports(&probe_ent->port[0]);
 
         return probe_ent;