diff --git a/drivers/gpu/drm/nouveau/nouveau_acpi.c b/drivers/gpu/drm/nouveau/nouveau_acpi.c
index dd7d2e182719..f9a2df29a593 100644
--- a/drivers/gpu/drm/nouveau/nouveau_acpi.c
+++ b/drivers/gpu/drm/nouveau/nouveau_acpi.c
@@ -317,6 +317,16 @@ static bool nouveau_dsm_detect(void)
 			has_optimus = 1;
 	}
 
+	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_3D << 8, pdev)) != NULL) {
+		vga_count++;
+
+		retval = nouveau_dsm_pci_probe(pdev);
+		if (retval & NOUVEAU_DSM_HAS_MUX)
+			has_dsm |= 1;
+		if (retval & NOUVEAU_DSM_HAS_OPT)
+			has_optimus = 1;
+	}
+
 	/* find the optimus DSM or the old v1 DSM */
 	if (has_optimus == 1) {
 		acpi_get_name(nouveau_dsm_priv.dhandle, ACPI_FULL_PATHNAME,