[PATCH] drm/panfrost: Fix module unload

From: Steven Price
Date: Fri Oct 30 2020 - 11:07:20 EST


When unloading the call to pm_runtime_put_sync_suspend() will attempt to
turn the GPU cores off, however panfrost_device_fini() will have turned
the clocks off. This leads to the hardware locking up.

Instead don't call pm_runtime_put_sync_suspend() and instead simply mark
the device as suspended using pm_runtime_set_suspended(). And also
include this on the error path in panfrost_probe().

Fixes: aebe8c22a912 ("drm/panfrost: Fix possible suspend in panfrost_remove")
Signed-off-by: Steven Price <steven.price@xxxxxxx>
---
drivers/gpu/drm/panfrost/panfrost_drv.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c
index 23513869500c..0ac8ad18fdc6 100644
--- a/drivers/gpu/drm/panfrost/panfrost_drv.c
+++ b/drivers/gpu/drm/panfrost/panfrost_drv.c
@@ -627,6 +627,7 @@ static int panfrost_probe(struct platform_device *pdev)
err_out1:
pm_runtime_disable(pfdev->dev);
panfrost_device_fini(pfdev);
+ pm_runtime_set_suspended(pfdev->dev);
err_out0:
drm_dev_put(ddev);
return err;
@@ -641,9 +642,9 @@ static int panfrost_remove(struct platform_device *pdev)
panfrost_gem_shrinker_cleanup(ddev);

pm_runtime_get_sync(pfdev->dev);
- panfrost_device_fini(pfdev);
- pm_runtime_put_sync_suspend(pfdev->dev);
pm_runtime_disable(pfdev->dev);
+ panfrost_device_fini(pfdev);
+ pm_runtime_set_suspended(pfdev->dev);

drm_dev_put(ddev);
return 0;
--
2.20.1