i7core_edac: return -ENODEV if no MC is found

Nehalem-EX uses a different memory controller. However, as the
memory controller is not visible on some Nehalem/Nehalem-EP, we
need to indirectly probe via a X58 PCI device. The same devices
are found on (some) Nehalem-EX. So, on those machines, the
probe routine needs to return -ENODEV, as the actual Memory
Controller registers won't be detected.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 18 insertions, 2 deletions

diff --git a/drivers/edac/i7core_edac.c b/drivers/edac/i7core_edac.c
index 304f550ed8d..6ae7795dea8 100644
--- a/drivers/edac/i7core_edac.c
+++ b/drivers/edac/i7core_edac.c
@@ -2226,7 +2226,7 @@ fail0:
 static int __devinit i7core_probe(struct pci_dev *pdev,
                                   const struct pci_device_id *id)
 {
-        int rc;
+        int rc, count = 0;
         struct i7core_dev *i7core_dev;
 
         /* get the pci devices we want to reserve for our use */
@@ -2246,12 +2246,28 @@ static int __devinit i7core_probe(struct pci_dev *pdev,
                 goto fail0;
 
         list_for_each_entry(i7core_dev, &i7core_edac_list, list) {
+                count++;
                 rc = i7core_register_mci(i7core_dev);
                 if (unlikely(rc < 0))
                         goto fail1;
         }
 
-        i7core_printk(KERN_INFO, "Driver loaded.\n");
+        /*
+         * Nehalem-EX uses a different memory controller. However, as the
+         * memory controller is not visible on some Nehalem/Nehalem-EP, we
+         * need to indirectly probe via a X58 PCI device. The same devices
+         * are found on (some) Nehalem-EX. So, on those machines, the
+         * probe routine needs to return -ENODEV, as the actual Memory
+         * Controller registers won't be detected.
+         */
+        if (!count) {
+                rc = -ENODEV;
+                goto fail1;
+        }
+
+        i7core_printk(KERN_INFO,
+                      "Driver loaded, %d memory controller(s) found.\n",
+                      count);
 
         mutex_unlock(&i7core_edac_lock);
         return 0;