[PATCH] drm/amdgpu/display: Fix reload driver error

[Emily Deng]

Issue:
Will have follow error when reload driver:
[ 3986.567739] sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:07.0/drm_dp_aux_dev'
[ 3986.567743] CPU: 6 PID: 1767 Comm: modprobe Tainted: G           OE     5.0.0-rc1-custom #1
[ 3986.567745] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
[ 3986.567746] Call Trace:
......
[ 3986.567808]  drm_dp_aux_register_devnode+0xdc/0x140 [drm_kms_helper]
......
[ 3986.569081] kobject_add_internal failed for drm_dp_aux_dev with -EEXIST, don't try to register things with the same name in the same directory.

Reproduce sequences:
1.modprobe amdgpu
2.modprobe -r amdgpu
3.modprobe amdgpu

Root cause:
When unload driver, it don't unregister aux.

Signed-off-by: Emily Deng <Emily.Deng at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h               |  1 +
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c      | 18 +++++++++++++++++-
 .../drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c    |  6 +++++-
 3 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
index e48fd35..720955b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
@@ -525,6 +525,7 @@ enum amdgpu_connector_dither {
 struct amdgpu_dm_dp_aux {
 	struct drm_dp_aux aux;
 	struct ddc_service *ddc_service;
+	bool has_aux;
 };
 
 struct amdgpu_i2c_adapter {
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 8fe1685..de369ae 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -3760,6 +3760,16 @@ int amdgpu_dm_connector_atomic_get_property(struct drm_connector *connector,
 	return ret;
 }
 
+static void amdgpu_dm_connector_unregister(struct drm_connector *connector)
+{
+	struct amdgpu_dm_connector *amdgpu_dm_connector = to_amdgpu_dm_connector(connector);
+
+	if (amdgpu_dm_connector->dm_dp_aux.has_aux) {
+		drm_dp_aux_unregister(&amdgpu_dm_connector->dm_dp_aux.aux);
+		amdgpu_dm_connector->dm_dp_aux.has_aux = false;
+	}
+}
+
 static void amdgpu_dm_connector_destroy(struct drm_connector *connector)
 {
 	struct amdgpu_dm_connector *aconnector = to_amdgpu_dm_connector(connector);
@@ -3788,6 +3798,11 @@ static void amdgpu_dm_connector_destroy(struct drm_connector *connector)
 	drm_dp_cec_unregister_connector(&aconnector->dm_dp_aux.aux);
 	drm_connector_unregister(connector);
 	drm_connector_cleanup(connector);
+	if (aconnector->i2c) {
+		i2c_del_adapter(&aconnector->i2c->base);
+		kfree(aconnector->i2c);
+	}
+
 	kfree(connector);
 }
 
@@ -3846,7 +3861,8 @@ static const struct drm_connector_funcs amdgpu_dm_connector_funcs = {
 	.atomic_duplicate_state = amdgpu_dm_connector_atomic_duplicate_state,
 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 	.atomic_set_property = amdgpu_dm_connector_atomic_set_property,
-	.atomic_get_property = amdgpu_dm_connector_atomic_get_property
+	.atomic_get_property = amdgpu_dm_connector_atomic_get_property,
+	.early_unregister = amdgpu_dm_connector_unregister
 };
 
 static int get_modes(struct drm_connector *connector)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
index 6e205ee..190e92c 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
@@ -387,12 +387,16 @@ static const struct drm_dp_mst_topology_cbs dm_mst_cbs = {
 void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm,
 				       struct amdgpu_dm_connector *aconnector)
 {
+	int ret;
 	aconnector->dm_dp_aux.aux.name = "dmdc";
 	aconnector->dm_dp_aux.aux.dev = dm->adev->dev;
 	aconnector->dm_dp_aux.aux.transfer = dm_dp_aux_transfer;
 	aconnector->dm_dp_aux.ddc_service = aconnector->dc_link->ddc;
 
-	drm_dp_aux_register(&aconnector->dm_dp_aux.aux);
+	ret = drm_dp_aux_register(&aconnector->dm_dp_aux.aux);
+	if (!ret)
+		aconnector->dm_dp_aux.has_aux = true;
+
 	drm_dp_cec_register_connector(&aconnector->dm_dp_aux.aux,
 				      aconnector->base.name, dm->adev->dev);
 	aconnector->mst_mgr.cbs = &dm_mst_cbs;
-- 
2.7.4