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<body><span class="vcard"><a class="email" href="mailto:imre.deak@intel.com" title="Imre Deak <imre.deak@intel.com>"> <span class="fn">Imre Deak</span></a>
</span> changed
<a class="bz_bug_link
bz_status_NEW "
title="NEW - [SKL] External VGA monitor not detected after DPMS/second hotplug"
href="https://bugs.freedesktop.org/show_bug.cgi?id=99114">bug 99114</a>
<br>
<table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>What</th>
<th>Removed</th>
<th>Added</th>
</tr>
<tr>
<td style="text-align:right;">i915 features</td>
<td>
</td>
<td>display/DP
</td>
</tr>
<tr>
<td style="text-align:right;">i915 platform</td>
<td>
</td>
<td>SKL
</td>
</tr></table>
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<b><a class="bz_bug_link
bz_status_NEW "
title="NEW - [SKL] External VGA monitor not detected after DPMS/second hotplug"
href="https://bugs.freedesktop.org/show_bug.cgi?id=99114#c5">Comment # 5</a>
on <a class="bz_bug_link
bz_status_NEW "
title="NEW - [SKL] External VGA monitor not detected after DPMS/second hotplug"
href="https://bugs.freedesktop.org/show_bug.cgi?id=99114">bug 99114</a>
from <span class="vcard"><a class="email" href="mailto:imre.deak@intel.com" title="Imre Deak <imre.deak@intel.com>"> <span class="fn">Imre Deak</span></a>
</span></b>
<pre>Looks like the DP->VGA adaptor NAKs the DPCD SINK_COUNT read during detection
while it's in low power state. At the same time it correctly returns the DPCD
receiver cap registers. Could you try the following:
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index db75bb9..e8673ba 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -4099,6 +4099,8 @@ intel_dp_detect_dpcd(struct intel_dp *intel_dp)
uint8_t *dpcd = intel_dp->dpcd;
uint8_t type;
+ intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
+
if (!intel_dp_get_dpcd(intel_dp))
return connector_status_disconnected;</pre>
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