[Nouveau] [PATCH 2/9] drm/nouveau: Forbid runtime pm on driver unload

[Lukas Wunner]

The PCI core calls pm_runtime_forbid() on device probe in pci_pm_init(),
making this the default state when nouveau is loaded. nouveau_drm_load()
therefore calls pm_runtime_allow(), but there's no pm_runtime_forbid()
in nouveau_drm_unload() to balance it. Add it so that we leave the
device in the same state that we found it.

This isn't a bug, it's just good housekeeping. When nouveau is first
loaded with runpm=1, then unloaded and loaded again with runpm=0,
pm_runtime_forbid() will be called from nouveau_pmops_runtime_idle() or
nouveau_pmops_runtime_suspend(), so the behaviour is correct. The nvidia
blob doesn't use runtime pm, but if it ever does, this commit avoids
that it has to clean up behind nouveau.

Tested-by: Karol Herbst <nouveau at karolherbst.de>
Signed-off-by: Lukas Wunner <lukas at wunner.de>
---
 drivers/gpu/drm/nouveau/nouveau_drm.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c
index faf7438..ef784b7 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -500,6 +500,7 @@ nouveau_drm_unload(struct drm_device *dev)
 
 	if (nouveau_runtime_pm != 0) {
 		pm_runtime_get_sync(dev->dev);
+		pm_runtime_forbid(dev->dev);
 	}
 
 	nouveau_fbcon_fini(dev);
-- 
2.8.1