1 files changed, 57 insertions, 38 deletions

diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c
index e38bc6769180..8df574316063 100644
--- a/drivers/gpu/drm/i915/intel_crt.c
+++ b/drivers/gpu/drm/i915/intel_crt.c
@@ -34,8 +34,17 @@
 #include "i915_drm.h"
 #include "i915_drv.h"
 
+/* Here's the desired hotplug mode */
+#define ADPA_HOTPLUG_BITS (ADPA_CRT_HOTPLUG_PERIOD_128 |                \
+                           ADPA_CRT_HOTPLUG_WARMUP_10MS |               \
+                           ADPA_CRT_HOTPLUG_SAMPLE_4S |                 \
+                           ADPA_CRT_HOTPLUG_VOLTAGE_50 |                \
+                           ADPA_CRT_HOTPLUG_VOLREF_325MV |              \
+                           ADPA_CRT_HOTPLUG_ENABLE)
+
 struct intel_crt {
         struct intel_encoder base;
+        bool force_hotplug_required;
 };
 
 static struct intel_crt *intel_attached_crt(struct drm_connector *connector)
@@ -139,7 +148,7 @@ static void intel_crt_mode_set(struct drm_encoder *encoder,
                            dpll_md & ~DPLL_MD_UDI_MULTIPLIER_MASK);
         }
 
-        adpa = 0;
+        adpa = ADPA_HOTPLUG_BITS;
         if (adjusted_mode->flags & DRM_MODE_FLAG_PHSYNC)
                 adpa |= ADPA_HSYNC_ACTIVE_HIGH;
         if (adjusted_mode->flags & DRM_MODE_FLAG_PVSYNC)
@@ -167,53 +176,44 @@ static void intel_crt_mode_set(struct drm_encoder *encoder,
 static bool intel_ironlake_crt_detect_hotplug(struct drm_connector *connector)
 {
         struct drm_device *dev = connector->dev;
+        struct intel_crt *crt = intel_attached_crt(connector);
         struct drm_i915_private *dev_priv = dev->dev_private;
-        u32 adpa, temp;
+        u32 adpa;
         bool ret;
-        bool turn_off_dac = false;
 
-        temp = adpa = I915_READ(PCH_ADPA);
+        /* The first time through, trigger an explicit detection cycle */
+        if (crt->force_hotplug_required) {
+                bool turn_off_dac = HAS_PCH_SPLIT(dev);
+                u32 save_adpa;
 
-        if (HAS_PCH_SPLIT(dev))
-                turn_off_dac = true;
-
-        adpa &= ~ADPA_CRT_HOTPLUG_MASK;
-        if (turn_off_dac)
-                adpa &= ~ADPA_DAC_ENABLE;
-
-        /* disable HPD first */
-        I915_WRITE(PCH_ADPA, adpa);
-        (void)I915_READ(PCH_ADPA);
-
-        adpa |= (ADPA_CRT_HOTPLUG_PERIOD_128 |
-                        ADPA_CRT_HOTPLUG_WARMUP_10MS |
-                        ADPA_CRT_HOTPLUG_SAMPLE_4S |
-                        ADPA_CRT_HOTPLUG_VOLTAGE_50 | /* default */
-                        ADPA_CRT_HOTPLUG_VOLREF_325MV |
-                        ADPA_CRT_HOTPLUG_ENABLE |
-                        ADPA_CRT_HOTPLUG_FORCE_TRIGGER);
-
-        DRM_DEBUG_KMS("pch crt adpa 0x%x", adpa);
-        I915_WRITE(PCH_ADPA, adpa);
-
-        if (wait_for((I915_READ(PCH_ADPA) & ADPA_CRT_HOTPLUG_FORCE_TRIGGER) == 0,
-                     1000))
-                DRM_DEBUG_KMS("timed out waiting for FORCE_TRIGGER");
-
-        if (turn_off_dac) {
-                /* Make sure hotplug is enabled */
-                I915_WRITE(PCH_ADPA, temp | ADPA_CRT_HOTPLUG_ENABLE);
-                (void)I915_READ(PCH_ADPA);
+                crt->force_hotplug_required = 0;
+
+                save_adpa = adpa = I915_READ(PCH_ADPA);
+                DRM_DEBUG_KMS("trigger hotplug detect cycle: adpa=0x%x\n", adpa);
+
+                adpa |= ADPA_CRT_HOTPLUG_FORCE_TRIGGER;
+                if (turn_off_dac)
+                        adpa &= ~ADPA_DAC_ENABLE;
+
+                I915_WRITE(PCH_ADPA, adpa);
+
+                if (wait_for((I915_READ(PCH_ADPA) & ADPA_CRT_HOTPLUG_FORCE_TRIGGER) == 0,
+                             1000))
+                        DRM_DEBUG_KMS("timed out waiting for FORCE_TRIGGER");
+
+                if (turn_off_dac) {
+                        I915_WRITE(PCH_ADPA, save_adpa);
+                        POSTING_READ(PCH_ADPA);
+                }
         }
 
         /* Check the status to see if both blue and green are on now */
         adpa = I915_READ(PCH_ADPA);
-        adpa &= ADPA_CRT_HOTPLUG_MONITOR_MASK;
-        if ((adpa == ADPA_CRT_HOTPLUG_MONITOR_COLOR) ||
-                (adpa == ADPA_CRT_HOTPLUG_MONITOR_MONO))
+        if ((adpa & ADPA_CRT_HOTPLUG_MONITOR_MASK) != 0)
                 ret = true;
         else
                 ret = false;
+        DRM_DEBUG_KMS("ironlake hotplug adpa=0x%x, result %d\n", adpa, ret);
 
         return ret;
 }
@@ -452,8 +452,10 @@ intel_crt_detect(struct drm_connector *connector, bool force)
                 if (intel_crt_detect_hotplug(connector)) {
                         DRM_DEBUG_KMS("CRT detected via hotplug\n");
                         return connector_status_connected;
-                } else
+                } else {
+                        DRM_DEBUG_KMS("CRT not detected via hotplug\n");
                         return connector_status_disconnected;
+                }
         }
 
         if (intel_crt_detect_ddc(crt))
@@ -587,5 +589,22 @@ void intel_crt_init(struct drm_device *dev)
         else
                 connector->polled = DRM_CONNECTOR_POLL_CONNECT;
 
+        /*
+         * Configure the automatic hotplug detection stuff
+         */
+        crt->force_hotplug_required = 0;
+        if (HAS_PCH_SPLIT(dev)) {
+                u32 adpa;
+
+                adpa = I915_READ(PCH_ADPA);
+                adpa &= ~ADPA_CRT_HOTPLUG_MASK;
+                adpa |= ADPA_HOTPLUG_BITS;
+                I915_WRITE(PCH_ADPA, adpa);
+                POSTING_READ(PCH_ADPA);
+
+                DRM_DEBUG_KMS("pch crt adpa set to 0x%x\n", adpa);
+                crt->force_hotplug_required = 1;
+        }
+
         dev_priv->hotplug_supported_mask |= CRT_HOTPLUG_INT_STATUS;
 }