Merge branch 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel...

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

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 6c8746c..d1e8ddb 100644 (file)
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -36,6 +36,7 @@
 #include <drm/i915_drm.h>
 #include "i915_drv.h"
 
+#define DP_RECEIVER_CAP_SIZE   0xf
 #define DP_LINK_STATUS_SIZE    6
 #define DP_LINK_CHECK_TIMEOUT  (10 * 1000)
 
@@ -1796,8 +1797,7 @@ intel_dp_start_link_train(struct intel_dp *intel_dp)
                        if ((intel_dp->train_set[i] & DP_TRAIN_MAX_SWING_REACHED) == 0)
                                break;
                if (i == intel_dp->lane_count && voltage_tries == 5) {
-                       ++loop_tries;
-                       if (loop_tries == 5) {
+                       if (++loop_tries == 5) {
                                DRM_DEBUG_KMS("too many full retries, give up\n");
                                break;
                        }
@@ -1807,15 +1807,11 @@ intel_dp_start_link_train(struct intel_dp *intel_dp)
                }
 
                /* Check to see if we've tried the same voltage 5 times */
-               if ((intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK) == voltage) {
-                       ++voltage_tries;
-                       if (voltage_tries == 5) {
-                               DRM_DEBUG_KMS("too many voltage retries, give up\n");
-                               break;
-                       }
-               } else
+               if ((intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK) != voltage) {
+                       voltage = intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
                        voltage_tries = 0;
-               voltage = intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
+               } else
+                       ++voltage_tries;
 
                /* Compute new intel_dp->train_set as requested by target */
                intel_get_adjust_train(intel_dp, link_status);
@@ -1963,12 +1959,25 @@ static bool
 intel_dp_get_dpcd(struct intel_dp *intel_dp)
 {
        if (intel_dp_aux_native_read_retry(intel_dp, 0x000, intel_dp->dpcd,
-                                          sizeof(intel_dp->dpcd)) &&
-           (intel_dp->dpcd[DP_DPCD_REV] != 0)) {
-               return true;
-       }
+                                          sizeof(intel_dp->dpcd)) == 0)
+               return false; /* aux transfer failed */
 
-       return false;
+       if (intel_dp->dpcd[DP_DPCD_REV] == 0)
+               return false; /* DPCD not present */
+
+       if (!(intel_dp->dpcd[DP_DOWNSTREAMPORT_PRESENT] &
+             DP_DWN_STRM_PORT_PRESENT))
+               return true; /* native DP sink */
+
+       if (intel_dp->dpcd[DP_DPCD_REV] == 0x10)
+               return true; /* no per-port downstream info */
+
+       if (intel_dp_aux_native_read_retry(intel_dp, DP_DOWNSTREAM_PORT_0,
+                                          intel_dp->downstream_ports,
+                                          DP_MAX_DOWNSTREAM_PORTS) == 0)
+               return false; /* downstream port status fetch failed */
+
+       return true;
 }
 
 static void
@@ -2068,11 +2077,43 @@ intel_dp_check_link_status(struct intel_dp *intel_dp)
        }
 }
 
+/* XXX this is probably wrong for multiple downstream ports */
 static enum drm_connector_status
 intel_dp_detect_dpcd(struct intel_dp *intel_dp)
 {
-       if (intel_dp_get_dpcd(intel_dp))
+       uint8_t *dpcd = intel_dp->dpcd;
+       bool hpd;
+       uint8_t type;
+
+       if (!intel_dp_get_dpcd(intel_dp))
+               return connector_status_disconnected;
+
+       /* if there's no downstream port, we're done */
+       if (!(dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_PRESENT))
+               return connector_status_connected;
+
+       /* If we're HPD-aware, SINK_COUNT changes dynamically */
+       hpd = !!(intel_dp->downstream_ports[0] & DP_DS_PORT_HPD);
+       if (hpd) {
+               uint8_t reg;
+               if (!intel_dp_aux_native_read_retry(intel_dp, DP_SINK_COUNT,
+                                                   &reg, 1))
+                       return connector_status_unknown;
+               return DP_GET_SINK_COUNT(reg) ? connector_status_connected
+                                             : connector_status_disconnected;
+       }
+
+       /* If no HPD, poke DDC gently */
+       if (drm_probe_ddc(&intel_dp->adapter))
                return connector_status_connected;
+
+       /* Well we tried, say unknown for unreliable port types */
+       type = intel_dp->downstream_ports[0] & DP_DS_PORT_TYPE_MASK;
+       if (type == DP_DS_PORT_TYPE_VGA || type == DP_DS_PORT_TYPE_NON_EDID)
+               return connector_status_unknown;
+
+       /* Anything else is out of spec, warn and ignore */
+       DRM_DEBUG_KMS("Broken DP branch device, ignoring\n");
        return connector_status_disconnected;
 }