[1/2][Ozone-Drm] Refactor GPU display management

ui/ozone/platform/drm/common/drm_util.cc

Index: ui/ozone/platform/drm/common/drm_util.cc
diff --git a/ui/ozone/platform/drm/common/drm_util.cc b/ui/ozone/platform/drm/common/drm_util.cc
index f85e3cd9c99d98c48255851d085a3d5627cf4e0f..b81866b19828a308d8c1cfdbe1bcc8a6ed637022 100644
--- a/ui/ozone/platform/drm/common/drm_util.cc
+++ b/ui/ozone/platform/drm/common/drm_util.cc
@@ -9,6 +9,12 @@
 #include <sys/mman.h>
 #include <xf86drmMode.h>
 
+#include "ui/display/util/edid_parser.h"
+
+#if !defined(DRM_MODE_CONNECTOR_DSI)
+#define DRM_MODE_CONNECTOR_DSI 16
+#endif
+
 namespace ui {
 
 namespace {
@@ -53,6 +59,96 @@ uint32_t GetCrtc(int fd,
   return 0;
 }
 
+// Computes the refresh rate for the specific mode. If we have enough
+// information use the mode timings to compute a more exact value otherwise
+// fallback to using the mode's vertical refresh rate (the kernel computes this
+// the same way, however there is a loss in precision since |vrefresh| is sent
+// as an integer).
+float GetRefreshRate(const drmModeModeInfo& mode) {
+  if (!mode.htotal || !mode.vtotal)
+    return mode.vrefresh;
+
+  float clock = mode.clock;
+  float htotal = mode.htotal;
+  float vtotal = mode.vtotal;
+
+  return (clock * 1000.0f) / (htotal * vtotal);
+}
+
+DisplayConnectionType GetDisplayType(drmModeConnector* connector) {
+  switch (connector->connector_type) {
+    case DRM_MODE_CONNECTOR_VGA:
+      return DISPLAY_CONNECTION_TYPE_VGA;
+    case DRM_MODE_CONNECTOR_DVII:
+    case DRM_MODE_CONNECTOR_DVID:
+    case DRM_MODE_CONNECTOR_DVIA:
+      return DISPLAY_CONNECTION_TYPE_DVI;
+    case DRM_MODE_CONNECTOR_LVDS:
+    case DRM_MODE_CONNECTOR_eDP:
+    case DRM_MODE_CONNECTOR_DSI:
+      return DISPLAY_CONNECTION_TYPE_INTERNAL;
+    case DRM_MODE_CONNECTOR_DisplayPort:
+      return DISPLAY_CONNECTION_TYPE_DISPLAYPORT;
+    case DRM_MODE_CONNECTOR_HDMIA:
+    case DRM_MODE_CONNECTOR_HDMIB:
+      return DISPLAY_CONNECTION_TYPE_HDMI;
+    default:
+      return DISPLAY_CONNECTION_TYPE_UNKNOWN;
+  }
+}
+
+int GetDrmProperty(int fd,
+                   drmModeConnector* connector,
+                   const std::string& name,
+                   ScopedDrmPropertyPtr* property) {
+  for (int i = 0; i < connector->count_props; ++i) {
+    ScopedDrmPropertyPtr tmp(drmModeGetProperty(fd, connector->props[i]));
+    if (!tmp)
+      continue;
+
+    if (name == tmp->name) {
+      *property = tmp.Pass();
+      return i;
+    }
+  }
+
+  return -1;
+}
+
+std::string GetNameForEnumValue(drmModePropertyRes* property, uint32_t value) {
+  for (int i = 0; i < property->count_enums; ++i)
+    if (property->enums[i].value == value)
+      return property->enums[i].name;
+
+  return std::string();
+}
+
+ScopedDrmPropertyBlobPtr GetDrmPropertyBlob(int fd,
+                                            drmModeConnector* connector,
+                                            const std::string& name) {
+  ScopedDrmPropertyPtr property;
+  int index = GetDrmProperty(fd, connector, name, &property);
+  if (index < 0)
+    return nullptr;
+
+  if (property->flags & DRM_MODE_PROP_BLOB) {
+    return ScopedDrmPropertyBlobPtr(
+        drmModeGetPropertyBlob(fd, connector->prop_values[index]));
+  }
+
+  return nullptr;
+}
+
+bool IsAspectPreserving(int fd, drmModeConnector* connector) {
+  ScopedDrmPropertyPtr property;
+  int index = GetDrmProperty(fd, connector, "scaling mode", &property);
+  if (index < 0)
+    return false;
+
+  return (GetNameForEnumValue(property.get(), connector->prop_values[index]) ==
+          "Full aspect");
+}
+
 }  // namespace
 
 HardwareDisplayControllerInfo::HardwareDisplayControllerInfo(
@@ -100,4 +196,69 @@ bool SameMode(const drmModeModeInfo& lhs, const drmModeModeInfo& rhs) {
          lhs.flags == rhs.flags && strcmp(lhs.name, rhs.name) == 0;
 }
 
+DisplayMode_Params CreateDisplayModeParams(const drmModeModeInfo& mode) {
+  DisplayMode_Params params;
+  params.size = gfx::Size(mode.hdisplay, mode.vdisplay);
+  params.is_interlaced = mode.flags & DRM_MODE_FLAG_INTERLACE;
+  params.refresh_rate = GetRefreshRate(mode);
+
+  return params;
+}
+
+DisplaySnapshot_Params CreateDisplaySnapshotParams(
+    HardwareDisplayControllerInfo* info,
+    int fd,
+    size_t display_index) {
+  DisplaySnapshot_Params params;
+  params.display_id = display_index;
+  params.physical_size =
+      gfx::Size(info->connector()->mmWidth, info->connector()->mmHeight);
+  params.type = GetDisplayType(info->connector());
+  params.is_aspect_preserving_scaling =
+      IsAspectPreserving(fd, info->connector());
+
+  ScopedDrmPropertyBlobPtr edid_blob(
+      GetDrmPropertyBlob(fd, info->connector(), "EDID"));
+
+  if (edid_blob) {
+    std::vector<uint8_t> edid(
+        static_cast<uint8_t*>(edid_blob->data),
+        static_cast<uint8_t*>(edid_blob->data) + edid_blob->length);
+
+    if (!GetDisplayIdFromEDID(edid, display_index, &params.display_id))
+      params.display_id = display_index;
+
+    ParseOutputDeviceData(edid, nullptr, &params.display_name, nullptr,
+                          nullptr);
+    ParseOutputOverscanFlag(edid, &params.has_overscan);
+  } else {
+    VLOG(1) << "Failed to get EDID blob for connector "
+            << info->connector()->connector_id;
+  }
+
+  for (int i = 0; i < info->connector()->count_modes; ++i) {
+    const drmModeModeInfo& mode = info->connector()->modes[i];
+    params.modes.push_back(CreateDisplayModeParams(mode));
+
+    if (info->crtc()->mode_valid && SameMode(info->crtc()->mode, mode)) {
+      params.has_current_mode = true;
+      params.current_mode = params.modes.back();
+    }
+
+    if (mode.type & DRM_MODE_TYPE_PREFERRED) {
+      params.has_native_mode = true;
+      params.native_mode = params.modes.back();
+    }
+  }
+
+  // If no preferred mode is found then use the first one. Using the first one
+  // since it should be the best mode.
+  if (!params.has_native_mode && !params.modes.empty()) {
+    params.has_native_mode = true;
+    params.native_mode = params.modes.front();
+  }
+
+  return params;
+}
+
 }  // namespace ui