drm/radeon/kms: add support for load detection on dp bridges

dp to vga bridges for example.

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

2 files changed, 68 insertions, 1 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c b/drivers/gpu/drm/radeon/radeon_connectors.c
index c04e18ee8a87..dc7852b3c5ca 100644
--- a/drivers/gpu/drm/radeon/radeon_connectors.c
+++ b/drivers/gpu/drm/radeon/radeon_connectors.c
@@ -1235,6 +1235,16 @@ radeon_dp_detect(struct drm_connector *connector, bool force)
                                         ret = connector_status_connected;
                         }
                 }
+
+                if ((ret == connector_status_disconnected) &&
+                    radeon_connector->dac_load_detect) {
+                        struct drm_encoder *encoder = radeon_best_single_encoder(connector);
+                        struct drm_encoder_helper_funcs *encoder_funcs;
+                        if (encoder) {
+                                encoder_funcs = encoder->helper_private;
+                                ret = encoder_funcs->detect(encoder, connector);
+                        }
+                }
         }
 
         radeon_connector_update_scratch_regs(connector, ret);
@@ -1408,6 +1418,10 @@ radeon_add_atom_connector(struct drm_device *dev,
                 default:
                         connector->interlace_allowed = true;
                         connector->doublescan_allowed = true;
+                        radeon_connector->dac_load_detect = true;
+                        drm_connector_attach_property(&radeon_connector->base,
+                                                      rdev->mode_info.load_detect_property,
+                                                      1);
                         break;
                 case DRM_MODE_CONNECTOR_DVII:
                 case DRM_MODE_CONNECTOR_DVID:
@@ -1429,6 +1443,12 @@ radeon_add_atom_connector(struct drm_device *dev,
                                 connector->doublescan_allowed = true;
                         else
                                 connector->doublescan_allowed = false;
+                        if (connector_type == DRM_MODE_CONNECTOR_DVII) {
+                                radeon_connector->dac_load_detect = true;
+                                drm_connector_attach_property(&radeon_connector->base,
+                                                              rdev->mode_info.load_detect_property,
+                                                              1);
+                        }
                         break;
                 case DRM_MODE_CONNECTOR_LVDS:
                 case DRM_MODE_CONNECTOR_eDP:
diff --git a/drivers/gpu/drm/radeon/radeon_encoders.c b/drivers/gpu/drm/radeon/radeon_encoders.c
index 39fa2258f235..d3449443aa1f 100644
--- a/drivers/gpu/drm/radeon/radeon_encoders.c
+++ b/drivers/gpu/drm/radeon/radeon_encoders.c
@@ -1999,6 +1999,53 @@ radeon_atom_dac_detect(struct drm_encoder *encoder, struct drm_connector *connec
         return connector_status_disconnected;
 }
 
+static enum drm_connector_status
+radeon_atom_dig_detect(struct drm_encoder *encoder, struct drm_connector *connector)
+{
+        struct drm_device *dev = encoder->dev;
+        struct radeon_device *rdev = dev->dev_private;
+        struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
+        struct radeon_connector *radeon_connector = to_radeon_connector(connector);
+        struct drm_encoder *ext_encoder = radeon_atom_get_external_encoder(encoder);
+        u32 bios_0_scratch;
+
+        if (!ASIC_IS_DCE4(rdev))
+                return connector_status_unknown;
+
+        if (!ext_encoder)
+                return connector_status_unknown;
+
+        if ((radeon_connector->devices & ATOM_DEVICE_CRT_SUPPORT) == 0)
+                return connector_status_unknown;
+
+        /* load detect on the dp bridge */
+        atombios_external_encoder_setup(encoder, ext_encoder,
+                                        EXTERNAL_ENCODER_ACTION_V3_DACLOAD_DETECTION);
+
+        bios_0_scratch = RREG32(R600_BIOS_0_SCRATCH);
+
+        DRM_DEBUG_KMS("Bios 0 scratch %x %08x\n", bios_0_scratch, radeon_encoder->devices);
+        if (radeon_connector->devices & ATOM_DEVICE_CRT1_SUPPORT) {
+                if (bios_0_scratch & ATOM_S0_CRT1_MASK)
+                        return connector_status_connected;
+        }
+        if (radeon_connector->devices & ATOM_DEVICE_CRT2_SUPPORT) {
+                if (bios_0_scratch & ATOM_S0_CRT2_MASK)
+                        return connector_status_connected;
+        }
+        if (radeon_connector->devices & ATOM_DEVICE_CV_SUPPORT) {
+                if (bios_0_scratch & (ATOM_S0_CV_MASK|ATOM_S0_CV_MASK_A))
+                        return connector_status_connected;
+        }
+        if (radeon_connector->devices & ATOM_DEVICE_TV1_SUPPORT) {
+                if (bios_0_scratch & (ATOM_S0_TV1_COMPOSITE | ATOM_S0_TV1_COMPOSITE_A))
+                        return connector_status_connected; /* CTV */
+                else if (bios_0_scratch & (ATOM_S0_TV1_SVIDEO | ATOM_S0_TV1_SVIDEO_A))
+                        return connector_status_connected; /* STV */
+        }
+        return connector_status_disconnected;
+}
+
 static void radeon_atom_encoder_prepare(struct drm_encoder *encoder)
 {
         struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
@@ -2162,7 +2209,7 @@ static const struct drm_encoder_helper_funcs radeon_atom_dig_helper_funcs = {
         .mode_set = radeon_atom_encoder_mode_set,
         .commit = radeon_atom_encoder_commit,
         .disable = radeon_atom_encoder_disable,
-        /* no detect for TMDS/LVDS yet */
+        .detect = radeon_atom_dig_detect,
 };
 
 static const struct drm_encoder_helper_funcs radeon_atom_dac_helper_funcs = {