Load and apply a vcgt table from an ICC file to the internal display

ui/ozone/platform/drm/gpu/drm_gpu_display_manager.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/ozone/platform/drm/gpu/drm_gpu_display_manager.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/file_descriptor_posix.h"
 #include "base/files/file.h"
@@ skipping 218 matching lines @@
       std::find_if(devices_.begin(), devices_.end(), FindByDevicePath(path));
   if (it == devices_.end()) {
     VLOG(2) << "Got request to remove non-existent device '" << path.value()
             << "'";
     return;
   }
 
   devices_.erase(it);
 }
 
+void DrmGpuDisplayManager::SetGammaRamp(int64_t id,
+                                        const std::vector<uint16_t>& r,
+                                        const std::vector<uint16_t>& g,
+                                        const std::vector<uint16_t>& b) {
+  DrmDisplaySnapshot* display = FindDisplaySnapshot(id);
+  if (!display) {
+    LOG(ERROR) << "There is no display with ID " << id;
+    return;
+  }
+
+  if (r.size() != g.size() || g.size() != b.size()) {
+    LOG(ERROR) << "Gamma ramp channels must all the same length.";
+  }
+
+  if (!display->drm()->SetGammaRamp(
+          display->crtc(), r.size(), const_cast<uint16_t*>(&r[0]),
+          const_cast<uint16_t*>(&g[0]), const_cast<uint16_t*>(&b[0]))) {

[spang, 2015/04/13 18:22:43]

Please move the casts closer to the ioctl in DrmDevice::SetGammaRamp().

[robert.bradford, 2015/04/17 16:42:46]

Done.

+    LOG(ERROR) << "Failed to set gamma ramp for display: crtc_id = "
+               << display->crtc() << " size = " << r.size();
+  }
+}
+
 DrmDisplaySnapshot* DrmGpuDisplayManager::FindDisplaySnapshot(int64_t id) {
   for (size_t i = 0; i < cached_displays_.size(); ++i)
     if (cached_displays_[i]->display_id() == id)
       return cached_displays_[i];
 
   return NULL;
 }
 
 const DrmDisplayMode* DrmGpuDisplayManager::FindDisplayMode(
     const gfx::Size& size,
@@ skipping 157 matching lines @@
 
     if (it == old_displays.end()) {
       screen_manager_->AddDisplayController(new_displays[i]->drm(),
                                             new_displays[i]->crtc(),
                                             new_displays[i]->connector());
     }
   }
 }
 
 }  // namespace ui