drm/amd/display: Fix DCE LVDS handling

LVDS does not use an HPD pin so it may be invalid.  Handle
this case correctly in link encoder creation.

Fixes: 7c8fb3b8e9ba ("drm/amd/display: Add hpd_source index check for DCE60/80/100/110/112/120 link encoders")
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/5012
Cc: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Cc: Roman Li <roman.li@amd.com>
Reviewed-by: Roman Li <roman.li@amd.com>
Reviewed-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 3b5620f7ee688177fcf65cf61588c5435bce1872)
Cc: stable@vger.kernel.org

6 files changed, 19 insertions, 22 deletions

diff --git a/drivers/gpu/drm/amd/display/dc/resource/dce100/dce100_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dce100/dce100_resource.c
index 92c123aca0c9..fdcf8db6be50 100644
--- a/drivers/gpu/drm/amd/display/dc/resource/dce100/dce100_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/resource/dce100/dce100_resource.c
@@ -650,9 +650,6 @@ static struct link_encoder *dce100_link_encoder_create(
 		return &enc110->base;
 	}
 
-	if (enc_init_data->hpd_source >= ARRAY_SIZE(link_enc_hpd_regs))
-		return NULL;
-
 	link_regs_id =
 		map_transmitter_id_to_phy_instance(enc_init_data->transmitter);
 
@@ -661,7 +658,8 @@ static struct link_encoder *dce100_link_encoder_create(
 				      &link_enc_feature,
 				      &link_enc_regs[link_regs_id],
 				      &link_enc_aux_regs[enc_init_data->channel - 1],
-				      &link_enc_hpd_regs[enc_init_data->hpd_source]);
+				      enc_init_data->hpd_source >= ARRAY_SIZE(link_enc_hpd_regs) ?
+				      NULL : &link_enc_hpd_regs[enc_init_data->hpd_source]);
 	return &enc110->base;
 }
 
diff --git a/drivers/gpu/drm/amd/display/dc/resource/dce110/dce110_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dce110/dce110_resource.c
index 95852d277c22..ab71f645c90e 100644
--- a/drivers/gpu/drm/amd/display/dc/resource/dce110/dce110_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/resource/dce110/dce110_resource.c
@@ -671,7 +671,7 @@ static struct link_encoder *dce110_link_encoder_create(
 		kzalloc_obj(struct dce110_link_encoder);
 	int link_regs_id;
 
-	if (!enc110 || enc_init_data->hpd_source >= ARRAY_SIZE(link_enc_hpd_regs))
+	if (!enc110)
 		return NULL;
 
 	link_regs_id =
@@ -682,7 +682,8 @@ static struct link_encoder *dce110_link_encoder_create(
 				      &link_enc_feature,
 				      &link_enc_regs[link_regs_id],
 				      &link_enc_aux_regs[enc_init_data->channel - 1],
-				      &link_enc_hpd_regs[enc_init_data->hpd_source]);
+				      enc_init_data->hpd_source >= ARRAY_SIZE(link_enc_hpd_regs) ?
+				      NULL : &link_enc_hpd_regs[enc_init_data->hpd_source]);
 	return &enc110->base;
 }
 
diff --git a/drivers/gpu/drm/amd/display/dc/resource/dce112/dce112_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dce112/dce112_resource.c
index 58c6a00397cf..b7051bfd4326 100644
--- a/drivers/gpu/drm/amd/display/dc/resource/dce112/dce112_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/resource/dce112/dce112_resource.c
@@ -632,7 +632,7 @@ static struct link_encoder *dce112_link_encoder_create(
 		kzalloc_obj(struct dce110_link_encoder);
 	int link_regs_id;
 
-	if (!enc110 || enc_init_data->hpd_source >= ARRAY_SIZE(link_enc_hpd_regs))
+	if (!enc110)
 		return NULL;
 
 	link_regs_id =
@@ -643,7 +643,8 @@ static struct link_encoder *dce112_link_encoder_create(
 				      &link_enc_feature,
 				      &link_enc_regs[link_regs_id],
 				      &link_enc_aux_regs[enc_init_data->channel - 1],
-				      &link_enc_hpd_regs[enc_init_data->hpd_source]);
+				      enc_init_data->hpd_source >= ARRAY_SIZE(link_enc_hpd_regs) ?
+				      NULL : &link_enc_hpd_regs[enc_init_data->hpd_source]);
 	return &enc110->base;
 }
 
diff --git a/drivers/gpu/drm/amd/display/dc/resource/dce120/dce120_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dce120/dce120_resource.c
index 71d76b021375..7ee70f7b3aa7 100644
--- a/drivers/gpu/drm/amd/display/dc/resource/dce120/dce120_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/resource/dce120/dce120_resource.c
@@ -716,7 +716,7 @@ static struct link_encoder *dce120_link_encoder_create(
 		kzalloc_obj(struct dce110_link_encoder);
 	int link_regs_id;
 
-	if (!enc110 || enc_init_data->hpd_source >= ARRAY_SIZE(link_enc_hpd_regs))
+	if (!enc110)
 		return NULL;
 
 	link_regs_id =
@@ -727,7 +727,8 @@ static struct link_encoder *dce120_link_encoder_create(
 				      &link_enc_feature,
 				      &link_enc_regs[link_regs_id],
 				      &link_enc_aux_regs[enc_init_data->channel - 1],
-				      &link_enc_hpd_regs[enc_init_data->hpd_source]);
+				      enc_init_data->hpd_source >= ARRAY_SIZE(link_enc_hpd_regs) ?
+				      NULL : &link_enc_hpd_regs[enc_init_data->hpd_source]);
 
 	return &enc110->base;
 }
diff --git a/drivers/gpu/drm/amd/display/dc/resource/dce60/dce60_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dce60/dce60_resource.c
index c27645708286..3d52973dd7f2 100644
--- a/drivers/gpu/drm/amd/display/dc/resource/dce60/dce60_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/resource/dce60/dce60_resource.c
@@ -746,18 +746,16 @@ static struct link_encoder *dce60_link_encoder_create(
 		return &enc110->base;
 	}
 
-	if (enc_init_data->hpd_source >= ARRAY_SIZE(link_enc_hpd_regs))
-		return NULL;
-
 	link_regs_id =
 		map_transmitter_id_to_phy_instance(enc_init_data->transmitter);
 
 	dce60_link_encoder_construct(enc110,
-				      enc_init_data,
-				      &link_enc_feature,
-				      &link_enc_regs[link_regs_id],
-				      &link_enc_aux_regs[enc_init_data->channel - 1],
-				      &link_enc_hpd_regs[enc_init_data->hpd_source]);
+				     enc_init_data,
+				     &link_enc_feature,
+				     &link_enc_regs[link_regs_id],
+				     &link_enc_aux_regs[enc_init_data->channel - 1],
+				     enc_init_data->hpd_source >= ARRAY_SIZE(link_enc_hpd_regs) ?
+				     NULL : &link_enc_hpd_regs[enc_init_data->hpd_source]);
 	return &enc110->base;
 }
 
diff --git a/drivers/gpu/drm/amd/display/dc/resource/dce80/dce80_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dce80/dce80_resource.c
index d66d8ac6d897..89927727a0d9 100644
--- a/drivers/gpu/drm/amd/display/dc/resource/dce80/dce80_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/resource/dce80/dce80_resource.c
@@ -752,9 +752,6 @@ static struct link_encoder *dce80_link_encoder_create(
 		return &enc110->base;
 	}
 
-	if (enc_init_data->hpd_source >= ARRAY_SIZE(link_enc_hpd_regs))
-		return NULL;
-
 	link_regs_id =
 		map_transmitter_id_to_phy_instance(enc_init_data->transmitter);
 
@@ -763,7 +760,8 @@ static struct link_encoder *dce80_link_encoder_create(
 				      &link_enc_feature,
 				      &link_enc_regs[link_regs_id],
 				      &link_enc_aux_regs[enc_init_data->channel - 1],
-				      &link_enc_hpd_regs[enc_init_data->hpd_source]);
+				      enc_init_data->hpd_source >= ARRAY_SIZE(link_enc_hpd_regs) ?
+				      NULL : &link_enc_hpd_regs[enc_init_data->hpd_source]);
 	return &enc110->base;
 }