pm80xx: configure PHY settings based on subsystem vendor ID

Previuosly, all PMC Sierra 80xx controllers are assumed to be a
motherboard controller, except if the subsystem vendor ID was equal to
PCI_VENDOR_ID_ADAPTEC.  The driver then attempts to load PHY settings
from NVRAM.  While this may be correct behavior for most controllers, it
does not work with Adaptec and ATTO controllers since they do not store
PHY settings in NVRAM and choose to use either custom PHY settings or
chip defaults.  Loading random values from NVRAM may cause the
controllers to malfunction in this edge case.
Signed-off-by: Benjamin Rood <brood@attotech.com>
Reviewed-by: Jack Wang <jinpu.wang@profitbricks.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/pm8001/pm8001_init.c

@@ -720,6 +720,23 @@ static int pm8001_get_phy_settings_info(struct pm8001_hba_info *pm8001_ha)
 	return 0;
 }
 
+/**
+ * pm8001_configure_phy_settings : Configures PHY settings based on vendor ID.
+ * @pm8001_ha : our hba.
+ */
+static int pm8001_configure_phy_settings(struct pm8001_hba_info *pm8001_ha)
+{
+	switch (pm8001_ha->pdev->subsystem_vendor) {
+	case PCI_VENDOR_ID_ATTO:
+	case PCI_VENDOR_ID_ADAPTEC2:
+	case 0:
+		return 0;
+
+	default:
+		return pm8001_get_phy_settings_info(pm8001_ha);
+	}
+}
+
 #ifdef PM8001_USE_MSIX
 /**
  * pm8001_setup_msix - enable MSI-X interrupt
@@ -902,12 +919,9 @@ static int pm8001_pci_probe(struct pci_dev *pdev,
 
 	pm8001_init_sas_add(pm8001_ha);
 	/* phy setting support for motherboard controller */
-	if (pdev->subsystem_vendor != PCI_VENDOR_ID_ADAPTEC2 &&
-		pdev->subsystem_vendor != 0) {
-		rc = pm8001_get_phy_settings_info(pm8001_ha);
-		if (rc)
-			goto err_out_shost;
-	}
+	if (pm8001_configure_phy_settings(pm8001_ha))
+		goto err_out_shost;
+
 	pm8001_post_sas_ha_init(shost, chip);
 	rc = sas_register_ha(SHOST_TO_SAS_HA(shost));
 	if (rc)