From 59f7ed9c780a80845b4fa1dbf214c69d3539e0a5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Fl=C3=B6ser?= <mgraesslin@kde.org>
Date: Tue, 31 Oct 2017 17:12:12 +0100
Subject: [PATCH] [platforms/drm] Forward the mode changes to the
 OutputInterface

Summary:
While KWin gained support for changing modes it did not yet forward it
to the Wayland OutputInterface. This change implements this missing todo
by finding the matching mode and marking it as current.

Test Plan: Run kinfocenter to verify the current mode is properly set.

Reviewers: #kwin, #plasma

Subscribers: plasma-devel, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D8578
---
 plugins/platforms/drm/drm_output.cpp | 40 +++++++++++++++++++---------
 1 file changed, 27 insertions(+), 13 deletions(-)

diff --git a/plugins/platforms/drm/drm_output.cpp b/plugins/platforms/drm/drm_output.cpp
index 5c19a95b49..40c3fd9db9 100644
--- a/plugins/platforms/drm/drm_output.cpp
+++ b/plugins/platforms/drm/drm_output.cpp
@@ -237,6 +237,24 @@ static QHash<int, QByteArray> s_connectorNames = {
     {DRM_MODE_CONNECTOR_DSI, QByteArrayLiteral("DSI")}
 };
 
+namespace {
+quint64 refreshRateForMode(_drmModeModeInfo *m)
+{
+    // Calculate higher precision (mHz) refresh rate
+    // logic based on Weston, see compositor-drm.c
+    quint64 refreshRate = (m->clock * 1000000LL / m->htotal + m->vtotal / 2) / m->vtotal;
+    if (m->flags & DRM_MODE_FLAG_INTERLACE) {
+        refreshRate *= 2;
+    }
+    if (m->flags & DRM_MODE_FLAG_DBLSCAN) {
+        refreshRate /= 2;
+    }
+    if (m->vscan > 1) {
+        refreshRate /= m->vscan;
+    }
+    return refreshRate;
+}
+}
 
 bool DrmOutput::init(drmModeConnector *connector)
 {
@@ -257,6 +275,14 @@ bool DrmOutput::init(drmModeConnector *connector)
         m_waylandOutput.clear();
     }
     m_waylandOutput = waylandServer()->display()->createOutput();
+    connect(this, &DrmOutput::modeChanged, this,
+        [this] {
+            if (m_waylandOutput.isNull()) {
+                return;
+            }
+            m_waylandOutput->setCurrentMode(QSize(m_mode.hdisplay, m_mode.vdisplay), refreshRateForMode(&m_mode));
+        }
+    );
     if (!m_waylandOutputDevice.isNull()) {
         delete m_waylandOutputDevice.data();
         m_waylandOutputDevice.clear();
@@ -324,18 +350,7 @@ bool DrmOutput::init(drmModeConnector *connector)
             deviceflags |= KWayland::Server::OutputDeviceInterface::ModeFlag::Preferred;
         }
 
-        // Calculate higher precision (mHz) refresh rate
-        // logic based on Weston, see compositor-drm.c
-        quint64 refreshRate = (m->clock * 1000000LL / m->htotal + m->vtotal / 2) / m->vtotal;
-        if (m->flags & DRM_MODE_FLAG_INTERLACE) {
-            refreshRate *= 2;
-        }
-        if (m->flags & DRM_MODE_FLAG_DBLSCAN) {
-            refreshRate /= 2;
-        }
-        if (m->vscan > 1) {
-            refreshRate /= m->vscan;
-        }
+        const auto refreshRate = refreshRateForMode(m);
         m_waylandOutput->addMode(QSize(m->hdisplay, m->vdisplay), flags, refreshRate);
 
         KWayland::Server::OutputDeviceInterface::Mode mode;
@@ -756,7 +771,6 @@ bool DrmOutput::commitChanges()
         qCDebug(KWIN_DRM) << "Setting new mode:" << m_changeset->mode();
         m_waylandOutputDevice->setCurrentMode(m_changeset->mode());
         updateMode(m_changeset->mode());
-        // FIXME: implement for wl_output
     }
     if (m_changeset->transformChanged()) {
         qCDebug(KWIN_DRM) << "Server setting transform: " << (int)(m_changeset->transform());