1 files changed, 20 insertions, 11 deletions

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 5ede4e8e290d..57552eb386b0 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -404,7 +404,7 @@ intel_dp_aux_ch(struct intel_dp *intel_dp,
         int i, ret, recv_bytes;
         uint32_t status;
         int try, precharge, clock = 0;
-        bool has_aux_irq = true;
+        bool has_aux_irq = HAS_AUX_IRQ(dev);
         uint32_t timeout;
 
         /* dp aux is extremely sensitive to irq latency, hence request the
@@ -537,6 +537,7 @@ intel_dp_aux_native_write(struct intel_dp *intel_dp,
         uint8_t msg[20];
         int msg_bytes;
         uint8_t ack;
+        int retry;
 
         if (WARN_ON(send_bytes > 16))
                 return -E2BIG;
@@ -548,19 +549,21 @@ intel_dp_aux_native_write(struct intel_dp *intel_dp,
         msg[3] = send_bytes - 1;
         memcpy(&msg[4], send, send_bytes);
         msg_bytes = send_bytes + 4;
-        for (;;) {
+        for (retry = 0; retry < 7; retry++) {
                 ret = intel_dp_aux_ch(intel_dp, msg, msg_bytes, &ack, 1);
                 if (ret < 0)
                         return ret;
                 ack >>= 4;
                 if ((ack & DP_AUX_NATIVE_REPLY_MASK) == DP_AUX_NATIVE_REPLY_ACK)
-                        break;
+                        return send_bytes;
                 else if ((ack & DP_AUX_NATIVE_REPLY_MASK) == DP_AUX_NATIVE_REPLY_DEFER)
-                        udelay(100);
+                        usleep_range(400, 500);
                 else
                         return -EIO;
         }
-        return send_bytes;
+
+        DRM_ERROR("too many retries, giving up\n");
+        return -EIO;
 }
 
 /* Write a single byte to the aux channel in native mode */
@@ -582,6 +585,7 @@ intel_dp_aux_native_read(struct intel_dp *intel_dp,
         int reply_bytes;
         uint8_t ack;
         int ret;
+        int retry;
 
         if (WARN_ON(recv_bytes > 19))
                 return -E2BIG;
@@ -595,7 +599,7 @@ intel_dp_aux_native_read(struct intel_dp *intel_dp,
         msg_bytes = 4;
         reply_bytes = recv_bytes + 1;
 
-        for (;;) {
+        for (retry = 0; retry < 7; retry++) {
                 ret = intel_dp_aux_ch(intel_dp, msg, msg_bytes,
                                       reply, reply_bytes);
                 if (ret == 0)
@@ -608,10 +612,13 @@ intel_dp_aux_native_read(struct intel_dp *intel_dp,
                         return ret - 1;
                 }
                 else if ((ack & DP_AUX_NATIVE_REPLY_MASK) == DP_AUX_NATIVE_REPLY_DEFER)
-                        udelay(100);
+                        usleep_range(400, 500);
                 else
                         return -EIO;
         }
+
+        DRM_ERROR("too many retries, giving up\n");
+        return -EIO;
 }
 
 static int
@@ -1869,10 +1876,12 @@ static void vlv_pre_enable_dp(struct intel_encoder *encoder)
 
         mutex_unlock(&dev_priv->dpio_lock);
 
-        /* init power sequencer on this pipe and port */
-        intel_dp_init_panel_power_sequencer(dev, intel_dp, &power_seq);
-        intel_dp_init_panel_power_sequencer_registers(dev, intel_dp,
-                                                      &power_seq);
+        if (is_edp(intel_dp)) {
+                /* init power sequencer on this pipe and port */
+                intel_dp_init_panel_power_sequencer(dev, intel_dp, &power_seq);
+                intel_dp_init_panel_power_sequencer_registers(dev, intel_dp,
+                                                              &power_seq);
+        }
 
         intel_enable_dp(encoder);