+
+/**
+ * Determine if the device really is AGP or not.
+ *
+ * In addition to the usual tests performed by \c drm_device_is_agp, this
+ * function detects PCI G450 cards that appear to the system exactly like
+ * AGP G450 cards.
+ *
+ * \param dev The device to be tested.
+ *
+ * \returns
+ * If the device is a PCI G450, zero is returned. Otherwise 2 is returned.
+ */
+static int mga_driver_device_is_agp(drm_device_t * dev)
+{
+ const struct pci_dev *const pdev = dev->pdev;
+
+ /* There are PCI versions of the G450. These cards have the
+ * same PCI ID as the AGP G450, but have an additional PCI-to-PCI
+ * bridge chip. We detect these cards, which are not currently
+ * supported by this driver, by looking at the device ID of the
+ * bus the "card" is on. If vendor is 0x3388 (Hint Corp) and the
+ * device is 0x0021 (HB6 Universal PCI-PCI bridge), we reject the
+ * device.
+ */
+
+ if ((pdev->device == 0x0525) && pdev->bus->self
+ && (pdev->bus->self->vendor == 0x3388)
+ && (pdev->bus->self->device == 0x0021)) {
+ return 0;
+ }
+
+ return 2;
+}