drm/nouveau: fix suspend/resume when in headless mode

commit 9430738d upstream.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
[jrnieder@gmail.com: backport to 3.2: make fbcon suspend/resume
 handling conditional in a vague hope that this will approximate what
 the original does for 3.3+]
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/gpu/drm/nouveau/nouveau_drv.c

@@ -178,8 +178,10 @@ nouveau_pci_suspend(struct pci_dev *pdev, pm_message_t pm_state)
 	if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
 		return 0;
 
-	NV_INFO(dev, "Disabling fbcon acceleration...\n");
-	nouveau_fbcon_save_disable_accel(dev);
+	if (dev->mode_config.num_crtc) {
+		NV_INFO(dev, "Disabling fbcon acceleration...\n");
+		nouveau_fbcon_save_disable_accel(dev);
+	}
 
 	NV_INFO(dev, "Unpinning framebuffer(s)...\n");
 	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
@@ -246,10 +248,12 @@ nouveau_pci_suspend(struct pci_dev *pdev, pm_message_t pm_state)
 		pci_set_power_state(pdev, PCI_D3hot);
 	}
 
-	console_lock();
-	nouveau_fbcon_set_suspend(dev, 1);
-	console_unlock();
-	nouveau_fbcon_restore_accel(dev);
+	if (dev->mode_config.num_crtc) {
+		console_lock();
+		nouveau_fbcon_set_suspend(dev, 1);
+		console_unlock();
+		nouveau_fbcon_restore_accel(dev);
+	}
 	return 0;
 
 out_abort:
@@ -275,7 +279,8 @@ nouveau_pci_resume(struct pci_dev *pdev)
 	if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
 		return 0;
 
-	nouveau_fbcon_save_disable_accel(dev);
+	if (dev->mode_config.num_crtc)
+		nouveau_fbcon_save_disable_accel(dev);
 
 	NV_INFO(dev, "We're back, enabling device...\n");
 	pci_set_power_state(pdev, PCI_D0);
@@ -376,15 +381,18 @@ nouveau_pci_resume(struct pci_dev *pdev)
 		nv_crtc->lut.depth = 0;
 	}
 
-	console_lock();
-	nouveau_fbcon_set_suspend(dev, 0);
-	console_unlock();
+	if (dev->mode_config.num_crtc) {
+		console_lock();
+		nouveau_fbcon_set_suspend(dev, 0);
+		console_unlock();
 
-	nouveau_fbcon_zfill_all(dev);
+		nouveau_fbcon_zfill_all(dev);
+	}
 
 	drm_helper_resume_force_mode(dev);
 
-	nouveau_fbcon_restore_accel(dev);
+	if (dev->mode_config.num_crtc)
+		nouveau_fbcon_restore_accel(dev);
 	return 0;
 }