[PATCH 2/3] drm/amd/display: Stop storing failures into adev->dm.cached_state

[Mario Limonciello <superm1@kernel.org>]

From: Mario Limonciello <mario.limonciello@amd.com>

If drm_atomic_helper_suspend() has failed for any reason, it's stored
in adev->dm.cached_state.  This isn't expected because the resume
(or complete()) sequence will attempt to use the stored state to
resume.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 25 +++++++++++++------
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 1797fa85fac6a..1f5894d8f2fb1 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -3060,6 +3060,19 @@ static void hpd_rx_irq_work_suspend(struct amdgpu_display_manager *dm)
 	}
 }
 
+static int dm_cache_state(struct amdgpu_device *adev)
+{
+	int r;
+
+	adev->dm.cached_state = drm_atomic_helper_suspend(adev_to_drm(adev));
+	if (IS_ERR(adev->dm.cached_state)) {
+		r = PTR_ERR(adev->dm.cached_state);
+		adev->dm.cached_state = NULL;
+	}
+
+	return adev->dm.cached_state ? 0 : r;
+}
+
 static int dm_prepare_suspend(struct amdgpu_ip_block *ip_block)
 {
 	struct amdgpu_device *adev = ip_block->adev;
@@ -3068,11 +3081,8 @@ static int dm_prepare_suspend(struct amdgpu_ip_block *ip_block)
 		return 0;
 
 	WARN_ON(adev->dm.cached_state);
-	adev->dm.cached_state = drm_atomic_helper_suspend(adev_to_drm(adev));
-	if (IS_ERR(adev->dm.cached_state))
-		return PTR_ERR(adev->dm.cached_state);
 
-	return 0;
+	return dm_cache_state(adev);
 }
 
 static int dm_suspend(struct amdgpu_ip_block *ip_block)
@@ -3106,9 +3116,10 @@ static int dm_suspend(struct amdgpu_ip_block *ip_block)
 	}
 
 	if (!adev->dm.cached_state) {
-		adev->dm.cached_state = drm_atomic_helper_suspend(adev_to_drm(adev));
-		if (IS_ERR(adev->dm.cached_state))
-			return PTR_ERR(adev->dm.cached_state);
+		int r = dm_cache_state(adev);
+
+		if (r)
+			return r;
 	}
 
 	s3_handle_hdmi_cec(adev_to_drm(adev), true);
-- 
2.43.0