agp/intel: put back check that we have a driver for the bridge.

On my 945 laptop + radeon GPU, I was getting an oops on boot without this
check which seems to have gotten dropped in the rework.

Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/char/agp/intel-agp.c b/drivers/char/agp/intel-agp.c
index 07a9aad28c11..034644eeedf2 100644
--- a/drivers/char/agp/intel-agp.c
+++ b/drivers/char/agp/intel-agp.c
@@ -885,6 +885,14 @@ static int __devinit agp_intel_probe(struct pci_dev *pdev,
                 return -ENODEV;
         }
 
+        if (!bridge->driver) {
+                if (cap_ptr)
+                        dev_warn(&pdev->dev, "can't find bridge device (chip_id: %04x)\n",
+                                 intel_agp_chipsets[i].gmch_chip_id);
+                agp_put_bridge(bridge);
+                return -ENODEV;
+        }
+
         bridge->dev = pdev;
         bridge->dev_private_data = NULL;