drm/radeon/kms/atom: set sane defaults in atombios_get_encoder_mode()

If there was no connector mapped to the encoder, atombios_get_encoder_mode()
returned 0 which is the id for DP.  Return something sane instead based on
the encoder id.  This avoids hitting the DP paths on non-DP encoders.

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 15 insertions, 3 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_encoders.c b/drivers/gpu/drm/radeon/radeon_encoders.c
index d55cb58283a..c6981dfd915 100644
--- a/drivers/gpu/drm/radeon/radeon_encoders.c
+++ b/drivers/gpu/drm/radeon/radeon_encoders.c
@@ -595,6 +595,7 @@ atombios_digital_setup(struct drm_encoder *encoder, int action)
 int
 atombios_get_encoder_mode(struct drm_encoder *encoder)
 {
+        struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
         struct drm_device *dev = encoder->dev;
         struct radeon_device *rdev = dev->dev_private;
         struct drm_connector *connector;
@@ -602,9 +603,20 @@ atombios_get_encoder_mode(struct drm_encoder *encoder)
         struct radeon_connector_atom_dig *dig_connector;
 
         connector = radeon_get_connector_for_encoder(encoder);
-        if (!connector)
-                return 0;
-
+        if (!connector) {
+                switch (radeon_encoder->encoder_id) {
+                case ENCODER_OBJECT_ID_INTERNAL_UNIPHY:
+                case ENCODER_OBJECT_ID_INTERNAL_UNIPHY1:
+                case ENCODER_OBJECT_ID_INTERNAL_UNIPHY2:
+                case ENCODER_OBJECT_ID_INTERNAL_KLDSCP_LVTMA:
+                case ENCODER_OBJECT_ID_INTERNAL_KLDSCP_DVO1:
+                        return ATOM_ENCODER_MODE_DVI;
+                case ENCODER_OBJECT_ID_INTERNAL_KLDSCP_DAC1:
+                case ENCODER_OBJECT_ID_INTERNAL_KLDSCP_DAC2:
+                default:
+                        return ATOM_ENCODER_MODE_CRT;
+                }
+        }
         radeon_connector = to_radeon_connector(connector);
 
         switch (connector->connector_type) {