drm/i915: Reject modeset when the same digital port is used more than once

[pandora-kernel.git] / drivers / gpu / drm / i915 / intel_display.c

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 910df02..6289bab 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -10153,6 +10153,48 @@ static bool check_encoder_cloning(struct intel_crtc *crtc)
        return true;
 }
 
+static bool check_digital_port_conflicts(struct drm_device *dev)
+{
+       struct intel_connector *connector;
+       unsigned int used_ports = 0;
+
+       /*
+        * Walk the connector list instead of the encoder
+        * list to detect the problem on ddi platforms
+        * where there's just one encoder per digital port.
+        */
+       list_for_each_entry(connector,
+                           &dev->mode_config.connector_list, base.head) {
+               struct intel_encoder *encoder = connector->new_encoder;
+
+               if (!encoder)
+                       continue;
+
+               WARN_ON(!encoder->new_crtc);
+
+               switch (encoder->type) {
+                       unsigned int port_mask;
+               case INTEL_OUTPUT_UNKNOWN:
+                       if (WARN_ON(!HAS_DDI(dev)))
+                               break;
+               case INTEL_OUTPUT_DISPLAYPORT:
+               case INTEL_OUTPUT_HDMI:
+               case INTEL_OUTPUT_EDP:
+                       port_mask = 1 << enc_to_dig_port(&encoder->base)->port;
+
+                       /* the same port mustn't appear more than once */
+                       if (used_ports & port_mask)
+                               return false;
+
+                       used_ports |= port_mask;
+               default:
+                       break;
+               }
+       }
+
+       return true;
+}
+
 static struct intel_crtc_config *
 intel_modeset_pipe_config(struct drm_crtc *crtc,
                          struct drm_framebuffer *fb,
@@ -10169,6 +10211,11 @@ intel_modeset_pipe_config(struct drm_crtc *crtc,
                return ERR_PTR(-EINVAL);
        }
 
+       if (!check_digital_port_conflicts(dev)) {
+               DRM_DEBUG_KMS("rejecting conflicting digital port configuration\n");
+               return ERR_PTR(-EINVAL);
+       }
+
        pipe_config = kzalloc(sizeof(*pipe_config), GFP_KERNEL);
        if (!pipe_config)
                return ERR_PTR(-ENOMEM);