drm/DrmDevice.cpp - android_external_drm_hwcomposer - Gitiles

 /*
  * Copyright (C) 2015 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #define LOG_TAG "hwc-drm-device"

 #include "DrmDevice.h"

 #include <fcntl.h>
 #include <xf86drm.h>
 #include <xf86drmMode.h>

 #include <algorithm>
 #include <array>
 #include <cerrno>
 #include <cinttypes>
 #include <cstdint>
 #include <sstream>
 #include <string>

 #include "drm/DrmPlane.h"
 #include "utils/log.h"
 #include "utils/properties.h"

 static void trim_left(std::string *str) {
   str->erase(std::begin(*str),
              std::find_if(std::begin(*str), std::end(*str),
                           [](int ch) { return std::isspace(ch) == 0; }));
 }

 static void trim_right(std::string *str) {
   str->erase(std::find_if(std::rbegin(*str), std::rend(*str),
                           [](int ch) { return std::isspace(ch) == 0; })
                  .base(),
              std::end(*str));
 }

 static void trim(std::string *str) {
   trim_left(str);
   trim_right(str);
 }

 namespace android {

 static std::vector<std::string> read_primary_display_order_prop() {
   std::array<char, PROPERTY_VALUE_MAX> display_order_buf{};
   property_get("vendor.hwc.drm.primary_display_order", display_order_buf.data(),
                "...");

   std::vector<std::string> display_order;
   std::istringstream str(display_order_buf.data());
   for (std::string conn_name; std::getline(str, conn_name, ',');) {
     trim(&conn_name);
     display_order.push_back(std::move(conn_name));
   }
   return display_order;
 }

 static std::vector<DrmConnector *> make_primary_display_candidates(
     const std::vector<std::unique_ptr<DrmConnector>> &connectors) {
   std::vector<DrmConnector *> primary_candidates;
   std::transform(std::begin(connectors), std::end(connectors),
                  std::back_inserter(primary_candidates),
                  [](const std::unique_ptr<DrmConnector> &conn) {
                    return conn.get();
                  });
   primary_candidates.erase(std::remove_if(std::begin(primary_candidates),
                                           std::end(primary_candidates),
                                           [](const DrmConnector *conn) {
                                             return conn->state() !=
                                                    DRM_MODE_CONNECTED;
                                           }),
                            std::end(primary_candidates));

   std::vector<std::string> display_order = read_primary_display_order_prop();
   bool use_other = display_order.back() == "...";

   // putting connectors from primary_display_order first
   auto curr_connector = std::begin(primary_candidates);
   for (const std::string &display_name : display_order) {
     auto it = std::find_if(std::begin(primary_candidates),
                            std::end(primary_candidates),
                            [&display_name](const DrmConnector *conn) {
                              return conn->name() == display_name;
                            });
     if (it != std::end(primary_candidates)) {
       std::iter_swap(it, curr_connector);
       ++curr_connector;
     }
   }

   if (use_other) {
     // then putting internal connectors second, everything else afterwards
     std::partition(curr_connector, std::end(primary_candidates),
                    [](const DrmConnector *conn) { return conn->internal(); });
   } else {
     primary_candidates.erase(curr_connector, std::end(primary_candidates));
   }

   return primary_candidates;
 }

 DrmDevice::DrmDevice() {
   self.reset(this);
   mDrmFbImporter = std::make_unique<DrmFbImporter>(self);
 }

 // NOLINTNEXTLINE (readability-function-cognitive-complexity): Fixme
 std::tuple<int, int> DrmDevice::Init(const char *path, int num_displays) {
   /* TODO: Use drmOpenControl here instead */
   fd_ = UniqueFd(open(path, O_RDWR | O_CLOEXEC));
   if (fd() < 0) {
     // NOLINTNEXTLINE(concurrency-mt-unsafe): Fixme
     ALOGE("Failed to open dri %s: %s", path, strerror(errno));
     return std::make_tuple(-ENODEV, 0);
   }

   int ret = drmSetClientCap(fd(), DRM_CLIENT_CAP_UNIVERSAL_PLANES, 1);
   if (ret) {
     ALOGE("Failed to set universal plane cap %d", ret);
     return std::make_tuple(ret, 0);
   }

   ret = drmSetClientCap(fd(), DRM_CLIENT_CAP_ATOMIC, 1);
   if (ret) {
     ALOGE("Failed to set atomic cap %d", ret);
     return std::make_tuple(ret, 0);
   }

 #ifdef DRM_CLIENT_CAP_WRITEBACK_CONNECTORS
   ret = drmSetClientCap(fd(), DRM_CLIENT_CAP_WRITEBACK_CONNECTORS, 1);
   if (ret) {
     ALOGI("Failed to set writeback cap %d", ret);
     ret = 0;
   }
 #endif

   uint64_t cap_value = 0;
   if (drmGetCap(fd(), DRM_CAP_ADDFB2_MODIFIERS, &cap_value)) {
     ALOGW("drmGetCap failed. Fallback to no modifier support.");
     cap_value = 0;
   }
   HasAddFb2ModifiersSupport_ = cap_value != 0;

   drmSetMaster(fd());
   if (!drmIsMaster(fd())) {
     ALOGE("DRM/KMS master access required");
     return std::make_tuple(-EACCES, 0);
   }

   auto res = MakeDrmModeResUnique(fd());
   if (!res) {
     ALOGE("Failed to get DrmDevice resources");
     return std::make_tuple(-ENODEV, 0);
   }

   min_resolution_ = std::pair<uint32_t, uint32_t>(res->min_width,
                                                   res->min_height);
   max_resolution_ = std::pair<uint32_t, uint32_t>(res->max_width,
                                                   res->max_height);

   // Assumes that the primary display will always be in the first
   // drm_device opened.
   bool found_primary = num_displays != 0;

   for (int i = 0; !ret && i < res->count_crtcs; ++i) {
     auto c = MakeDrmModeCrtcUnique(fd(), res->crtcs[i]);
     if (!c) {
       ALOGE("Failed to get crtc %d", res->crtcs[i]);
       ret = -ENODEV;
       break;
     }

     std::unique_ptr<DrmCrtc> crtc(new DrmCrtc(this, c.get(), i));

     ret = crtc->Init();
     if (ret) {
       ALOGE("Failed to initialize crtc %d", res->crtcs[i]);
       break;
     }
     crtcs_.emplace_back(std::move(crtc));
   }

   std::vector<uint32_t> possible_clones;
   for (int i = 0; !ret && i < res->count_encoders; ++i) {
     auto e = MakeDrmModeEncoderUnique(fd(), res->encoders[i]);
     if (!e) {
       ALOGE("Failed to get encoder %d", res->encoders[i]);
       ret = -ENODEV;
       break;
     }

     std::vector<DrmCrtc *> possible_crtcs;
     DrmCrtc *current_crtc = nullptr;
     for (auto &crtc : crtcs_) {
       if ((1 << crtc->pipe()) & e->possible_crtcs)
         possible_crtcs.push_back(crtc.get());

       if (crtc->id() == e->crtc_id)
         current_crtc = crtc.get();
     }

     std::unique_ptr<DrmEncoder> enc(
         new DrmEncoder(e.get(), current_crtc, possible_crtcs));
     possible_clones.push_back(e->possible_clones);

     encoders_.emplace_back(std::move(enc));
   }

   for (unsigned int i = 0; i < encoders_.size(); i++) {
     for (unsigned int j = 0; j < encoders_.size(); j++)
       if (possible_clones[i] & (1 << j))
         encoders_[i]->AddPossibleClone(encoders_[j].get());
   }

   for (int i = 0; !ret && i < res->count_connectors; ++i) {
     auto c = MakeDrmModeConnectorUnique(fd(), res->connectors[i]);
     if (!c) {
       ALOGE("Failed to get connector %d", res->connectors[i]);
       ret = -ENODEV;
       break;
     }

     std::vector<DrmEncoder *> possible_encoders;
     DrmEncoder *current_encoder = nullptr;
     for (int j = 0; j < c->count_encoders; ++j) {
       for (auto &encoder : encoders_) {
         if (encoder->id() == c->encoders[j])
           possible_encoders.push_back(encoder.get());
         if (encoder->id() == c->encoder_id)
           current_encoder = encoder.get();
       }
     }

     std::unique_ptr<DrmConnector> conn(
         new DrmConnector(this, c.get(), current_encoder, possible_encoders));

     ret = conn->Init();
     if (ret) {
       ALOGE("Init connector %d failed", res->connectors[i]);
       break;
     }

     if (conn->writeback())
       writeback_connectors_.emplace_back(std::move(conn));
     else
       connectors_.emplace_back(std::move(conn));
   }

   // Primary display priority:
   // 1) vendor.hwc.drm.primary_display_order property
   // 2) internal connectors
   // 3) anything else
   std::vector<DrmConnector *>
       primary_candidates = make_primary_display_candidates(connectors_);
   if (!primary_candidates.empty() && !found_primary) {
     DrmConnector &conn = **std::begin(primary_candidates);
     conn.set_display(num_displays);
     displays_[num_displays] = num_displays;
     ++num_displays;
     found_primary = true;
   } else {
     ALOGE(
         "Failed to find primary display from "
         "\"vendor.hwc.drm.primary_display_order\" property");
   }

   // If no priority display were found then pick first available as primary and
   // for the others assign consecutive display_numbers.
   for (auto &conn : connectors_) {
     if (conn->external() || conn->internal()) {
       if (!found_primary) {
         conn->set_display(num_displays);
         displays_[num_displays] = num_displays;
         found_primary = true;
         ++num_displays;
       } else if (conn->display() < 0) {
         conn->set_display(num_displays);
         displays_[num_displays] = num_displays;
         ++num_displays;
       }
     }
   }

   // Catch-all for the above loops
   if (ret)
     return std::make_tuple(ret, 0);

   auto plane_res = MakeDrmModePlaneResUnique(fd());
   if (!plane_res) {
     ALOGE("Failed to get plane resources");
     return std::make_tuple(-ENOENT, 0);
   }

   for (uint32_t i = 0; i < plane_res->count_planes; ++i) {
     auto p = MakeDrmModePlaneUnique(fd(), plane_res->planes[i]);
     if (!p) {
       ALOGE("Failed to get plane %d", plane_res->planes[i]);
       ret = -ENODEV;
       break;
     }

     std::unique_ptr<DrmPlane> plane(new DrmPlane(this, p.get()));

     ret = plane->Init();
     if (ret) {
       ALOGE("Init plane %d failed", plane_res->planes[i]);
       break;
     }

     planes_.emplace_back(std::move(plane));
   }
   if (ret)
     return std::make_tuple(ret, 0);

   for (auto &conn : connectors_) {
     ret = CreateDisplayPipe(conn.get());
     if (ret) {
       ALOGE("Failed CreateDisplayPipe %d with %d", conn->id(), ret);
       return std::make_tuple(ret, 0);
     }
   }
   return std::make_tuple(ret, displays_.size());
 }

 bool DrmDevice::HandlesDisplay(int display) const {
   return displays_.find(display) != displays_.end();
 }

 DrmConnector *DrmDevice::GetConnectorForDisplay(int display) const {
   for (const auto &conn : connectors_) {
     if (conn->display() == display)
       return conn.get();
   }
   return nullptr;
 }

 DrmCrtc *DrmDevice::GetCrtcForDisplay(int display) const {
   for (const auto &crtc : crtcs_) {
     if (crtc->display() == display)
       return crtc.get();
   }
   return nullptr;
 }

 const std::vector<std::unique_ptr<DrmCrtc>> &DrmDevice::crtcs() const {
   return crtcs_;
 }

 uint32_t DrmDevice::next_mode_id() {
   return ++mode_id_;
 }

 int DrmDevice::TryEncoderForDisplay(int display, DrmEncoder *enc) {
   /* First try to use the currently-bound crtc */
   DrmCrtc *crtc = enc->crtc();
   if (crtc && crtc->can_bind(display)) {
     crtc->set_display(display);
     enc->set_crtc(crtc);
     return 0;
   }

   /* Try to find a possible crtc which will work */
   for (DrmCrtc *crtc : enc->possible_crtcs()) {
     /* We've already tried this earlier */
     if (crtc == enc->crtc())
       continue;

     if (crtc->can_bind(display)) {
       crtc->set_display(display);
       enc->set_crtc(crtc);
       return 0;
     }
   }

   /* We can't use the encoder, but nothing went wrong, try another one */
   return -EAGAIN;
 }

 int DrmDevice::CreateDisplayPipe(DrmConnector *connector) {
   int display = connector->display();
   /* Try to use current setup first */
   if (connector->encoder()) {
     int ret = TryEncoderForDisplay(display, connector->encoder());
     if (!ret) {
       return 0;
     }

     if (ret != -EAGAIN) {
       ALOGE("Could not set mode %d/%d", display, ret);
       return ret;
     }
   }

   for (DrmEncoder *enc : connector->possible_encoders()) {
     int ret = TryEncoderForDisplay(display, enc);
     if (!ret) {
       connector->set_encoder(enc);
       return 0;
     }

     if (ret != -EAGAIN) {
       ALOGE("Could not set mode %d/%d", display, ret);
       return ret;
     }
   }
   ALOGE("Could not find a suitable encoder/crtc for display %d",
         connector->display());
   return -ENODEV;
 }

 auto DrmDevice::RegisterUserPropertyBlob(void *data, size_t length) const
     -> DrmModeUserPropertyBlobUnique {
   struct drm_mode_create_blob create_blob {};
   create_blob.length = length;
   create_blob.data = (__u64)data;

   int ret = drmIoctl(fd(), DRM_IOCTL_MODE_CREATEPROPBLOB, &create_blob);
   if (ret) {
     ALOGE("Failed to create mode property blob %d", ret);
     return {};
   }

   return DrmModeUserPropertyBlobUnique(
       new uint32_t(create_blob.blob_id), [this](const uint32_t *it) {
         struct drm_mode_destroy_blob destroy_blob {};
         destroy_blob.blob_id = (__u32)*it;
         int err = drmIoctl(fd(), DRM_IOCTL_MODE_DESTROYPROPBLOB, &destroy_blob);
         if (err != 0) {
           ALOGE("Failed to destroy mode property blob %" PRIu32 "/%d", *it,
                 err);
         }
         // NOLINTNEXTLINE(cppcoreguidelines-owning-memory)
         delete it;
       });
 }

 int DrmDevice::GetProperty(uint32_t obj_id, uint32_t obj_type,
                            const char *prop_name, DrmProperty *property) const {
   drmModeObjectPropertiesPtr props = nullptr;

   props = drmModeObjectGetProperties(fd(), obj_id, obj_type);
   if (!props) {
     ALOGE("Failed to get properties for %d/%x", obj_id, obj_type);
     return -ENODEV;
   }

   bool found = false;
   for (int i = 0; !found && (size_t)i < props->count_props; ++i) {
     drmModePropertyPtr p = drmModeGetProperty(fd(), props->props[i]);
     if (!strcmp(p->name, prop_name)) {
       property->Init(obj_id, p, props->prop_values[i]);
       found = true;
     }
     drmModeFreeProperty(p);
   }

   drmModeFreeObjectProperties(props);
   return found ? 0 : -ENOENT;
 }

 int DrmDevice::GetCrtcProperty(const DrmCrtc &crtc, const char *prop_name,
                                DrmProperty *property) const {
   return GetProperty(crtc.id(), DRM_MODE_OBJECT_CRTC, prop_name, property);
 }

 int DrmDevice::GetConnectorProperty(const DrmConnector &connector,
                                     const char *prop_name,
                                     DrmProperty *property) const {
   return GetProperty(connector.id(), DRM_MODE_OBJECT_CONNECTOR, prop_name,
                      property);
 }

 std::string DrmDevice::GetName() const {
   auto *ver = drmGetVersion(fd());
   if (!ver) {
     ALOGW("Failed to get drm version for fd=%d", fd());
     return "generic";
   }

   std::string name(ver->name);
   drmFreeVersion(ver);
   return name;
 }

 auto DrmDevice::IsKMSDev(const char *path) -> bool {
   auto fd = UniqueFd(open(path, O_RDWR | O_CLOEXEC));
   if (!fd) {
     return false;
   }

   auto res = MakeDrmModeResUnique(fd.Get());
   if (!res) {
     return false;
   }

   bool is_kms = res->count_crtcs > 0 && res->count_connectors > 0 &&
                 res->count_encoders > 0;

   return is_kms;
 }

 }  // namespace android
	/*
	* Copyright (C) 2015 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#define LOG_TAG "hwc-drm-device"

	#include "DrmDevice.h"

	#include <fcntl.h>
	#include <xf86drm.h>
	#include <xf86drmMode.h>

	#include <algorithm>
	#include <array>
	#include <cerrno>
	#include <cinttypes>
	#include <cstdint>
	#include <sstream>
	#include <string>

	#include "drm/DrmPlane.h"
	#include "utils/log.h"
	#include "utils/properties.h"

	static void trim_left(std::string *str) {
	str->erase(std::begin(*str),
	std::find_if(std::begin(str), std::end(str),
	[](int ch) { return std::isspace(ch) == 0; }));
	}

	static void trim_right(std::string *str) {
	str->erase(std::find_if(std::rbegin(str), std::rend(str),
	[](int ch) { return std::isspace(ch) == 0; })
	.base(),
	std::end(*str));
	}

	static void trim(std::string *str) {
	trim_left(str);
	trim_right(str);
	}

	namespace android {

	static std::vector<std::string> read_primary_display_order_prop() {
	std::array<char, PROPERTY_VALUE_MAX> display_order_buf{};
	property_get("vendor.hwc.drm.primary_display_order", display_order_buf.data(),
	"...");

	std::vector<std::string> display_order;
	std::istringstream str(display_order_buf.data());
	for (std::string conn_name; std::getline(str, conn_name, ',');) {
	trim(&conn_name);
	display_order.push_back(std::move(conn_name));
	}
	return display_order;
	}

	static std::vector<DrmConnector *> make_primary_display_candidates(
	const std::vector<std::unique_ptr<DrmConnector>> &connectors) {
	std::vector<DrmConnector *> primary_candidates;
	std::transform(std::begin(connectors), std::end(connectors),
	std::back_inserter(primary_candidates),
	[](const std::unique_ptr<DrmConnector> &conn) {
	return conn.get();
	});
	primary_candidates.erase(std::remove_if(std::begin(primary_candidates),
	std::end(primary_candidates),
	[](const DrmConnector *conn) {
	return conn->state() !=
	DRM_MODE_CONNECTED;
	}),
	std::end(primary_candidates));

	std::vector<std::string> display_order = read_primary_display_order_prop();
	bool use_other = display_order.back() == "...";

	// putting connectors from primary_display_order first
	auto curr_connector = std::begin(primary_candidates);
	for (const std::string &display_name : display_order) {
	auto it = std::find_if(std::begin(primary_candidates),
	std::end(primary_candidates),
	[&display_name](const DrmConnector *conn) {
	return conn->name() == display_name;
	});
	if (it != std::end(primary_candidates)) {
	std::iter_swap(it, curr_connector);
	++curr_connector;
	}
	}

	if (use_other) {
	// then putting internal connectors second, everything else afterwards
	std::partition(curr_connector, std::end(primary_candidates),
	[](const DrmConnector *conn) { return conn->internal(); });
	} else {
	primary_candidates.erase(curr_connector, std::end(primary_candidates));
	}

	return primary_candidates;
	}

	DrmDevice::DrmDevice() {
	self.reset(this);
	mDrmFbImporter = std::make_unique<DrmFbImporter>(self);
	}

	// NOLINTNEXTLINE (readability-function-cognitive-complexity): Fixme
	std::tuple<int, int> DrmDevice::Init(const char *path, int num_displays) {
	/* TODO: Use drmOpenControl here instead */
	fd_ = UniqueFd(open(path, O_RDWR \| O_CLOEXEC));
	if (fd() < 0) {
	// NOLINTNEXTLINE(concurrency-mt-unsafe): Fixme
	ALOGE("Failed to open dri %s: %s", path, strerror(errno));
	return std::make_tuple(-ENODEV, 0);
	}

	int ret = drmSetClientCap(fd(), DRM_CLIENT_CAP_UNIVERSAL_PLANES, 1);
	if (ret) {
	ALOGE("Failed to set universal plane cap %d", ret);
	return std::make_tuple(ret, 0);
	}

	ret = drmSetClientCap(fd(), DRM_CLIENT_CAP_ATOMIC, 1);
	if (ret) {
	ALOGE("Failed to set atomic cap %d", ret);
	return std::make_tuple(ret, 0);
	}

	#ifdef DRM_CLIENT_CAP_WRITEBACK_CONNECTORS
	ret = drmSetClientCap(fd(), DRM_CLIENT_CAP_WRITEBACK_CONNECTORS, 1);
	if (ret) {
	ALOGI("Failed to set writeback cap %d", ret);
	ret = 0;
	}
	#endif

	uint64_t cap_value = 0;
	if (drmGetCap(fd(), DRM_CAP_ADDFB2_MODIFIERS, &cap_value)) {
	ALOGW("drmGetCap failed. Fallback to no modifier support.");
	cap_value = 0;
	}
	HasAddFb2ModifiersSupport_ = cap_value != 0;

	drmSetMaster(fd());
	if (!drmIsMaster(fd())) {
	ALOGE("DRM/KMS master access required");
	return std::make_tuple(-EACCES, 0);
	}

	auto res = MakeDrmModeResUnique(fd());
	if (!res) {
	ALOGE("Failed to get DrmDevice resources");
	return std::make_tuple(-ENODEV, 0);
	}

	min_resolution_ = std::pair<uint32_t, uint32_t>(res->min_width,
	res->min_height);
	max_resolution_ = std::pair<uint32_t, uint32_t>(res->max_width,
	res->max_height);

	// Assumes that the primary display will always be in the first
	// drm_device opened.
	bool found_primary = num_displays != 0;

	for (int i = 0; !ret && i < res->count_crtcs; ++i) {
	auto c = MakeDrmModeCrtcUnique(fd(), res->crtcs[i]);
	if (!c) {
	ALOGE("Failed to get crtc %d", res->crtcs[i]);
	ret = -ENODEV;
	break;
	}

	std::unique_ptr<DrmCrtc> crtc(new DrmCrtc(this, c.get(), i));

	ret = crtc->Init();
	if (ret) {
	ALOGE("Failed to initialize crtc %d", res->crtcs[i]);
	break;
	}
	crtcs_.emplace_back(std::move(crtc));
	}

	std::vector<uint32_t> possible_clones;
	for (int i = 0; !ret && i < res->count_encoders; ++i) {
	auto e = MakeDrmModeEncoderUnique(fd(), res->encoders[i]);
	if (!e) {
	ALOGE("Failed to get encoder %d", res->encoders[i]);
	ret = -ENODEV;
	break;
	}

	std::vector<DrmCrtc *> possible_crtcs;
	DrmCrtc *current_crtc = nullptr;
	for (auto &crtc : crtcs_) {
	if ((1 << crtc->pipe()) & e->possible_crtcs)
	possible_crtcs.push_back(crtc.get());

	if (crtc->id() == e->crtc_id)
	current_crtc = crtc.get();
	}

	std::unique_ptr<DrmEncoder> enc(
	new DrmEncoder(e.get(), current_crtc, possible_crtcs));
	possible_clones.push_back(e->possible_clones);

	encoders_.emplace_back(std::move(enc));
	}

	for (unsigned int i = 0; i < encoders_.size(); i++) {
	for (unsigned int j = 0; j < encoders_.size(); j++)
	if (possible_clones[i] & (1 << j))
	encoders_[i]->AddPossibleClone(encoders_[j].get());
	}

	for (int i = 0; !ret && i < res->count_connectors; ++i) {
	auto c = MakeDrmModeConnectorUnique(fd(), res->connectors[i]);
	if (!c) {
	ALOGE("Failed to get connector %d", res->connectors[i]);
	ret = -ENODEV;
	break;
	}

	std::vector<DrmEncoder *> possible_encoders;
	DrmEncoder *current_encoder = nullptr;
	for (int j = 0; j < c->count_encoders; ++j) {
	for (auto &encoder : encoders_) {
	if (encoder->id() == c->encoders[j])
	possible_encoders.push_back(encoder.get());
	if (encoder->id() == c->encoder_id)
	current_encoder = encoder.get();
	}
	}

	std::unique_ptr<DrmConnector> conn(
	new DrmConnector(this, c.get(), current_encoder, possible_encoders));

	ret = conn->Init();
	if (ret) {
	ALOGE("Init connector %d failed", res->connectors[i]);
	break;
	}

	if (conn->writeback())
	writeback_connectors_.emplace_back(std::move(conn));
	else
	connectors_.emplace_back(std::move(conn));
	}

	// Primary display priority:
	// 1) vendor.hwc.drm.primary_display_order property
	// 2) internal connectors
	// 3) anything else
	std::vector<DrmConnector *>
	primary_candidates = make_primary_display_candidates(connectors_);
	if (!primary_candidates.empty() && !found_primary) {
	DrmConnector &conn = **std::begin(primary_candidates);
	conn.set_display(num_displays);
	displays_[num_displays] = num_displays;
	++num_displays;
	found_primary = true;
	} else {
	ALOGE(
	"Failed to find primary display from "
	"\"vendor.hwc.drm.primary_display_order\" property");
	}

	// If no priority display were found then pick first available as primary and
	// for the others assign consecutive display_numbers.
	for (auto &conn : connectors_) {
	if (conn->external() \|\| conn->internal()) {
	if (!found_primary) {
	conn->set_display(num_displays);
	displays_[num_displays] = num_displays;
	found_primary = true;
	++num_displays;
	} else if (conn->display() < 0) {
	conn->set_display(num_displays);
	displays_[num_displays] = num_displays;
	++num_displays;
	}
	}
	}

	// Catch-all for the above loops
	if (ret)
	return std::make_tuple(ret, 0);

	auto plane_res = MakeDrmModePlaneResUnique(fd());
	if (!plane_res) {
	ALOGE("Failed to get plane resources");
	return std::make_tuple(-ENOENT, 0);
	}

	for (uint32_t i = 0; i < plane_res->count_planes; ++i) {
	auto p = MakeDrmModePlaneUnique(fd(), plane_res->planes[i]);
	if (!p) {
	ALOGE("Failed to get plane %d", plane_res->planes[i]);
	ret = -ENODEV;
	break;
	}

	std::unique_ptr<DrmPlane> plane(new DrmPlane(this, p.get()));

	ret = plane->Init();
	if (ret) {
	ALOGE("Init plane %d failed", plane_res->planes[i]);
	break;
	}

	planes_.emplace_back(std::move(plane));
	}
	if (ret)
	return std::make_tuple(ret, 0);

	for (auto &conn : connectors_) {
	ret = CreateDisplayPipe(conn.get());
	if (ret) {
	ALOGE("Failed CreateDisplayPipe %d with %d", conn->id(), ret);
	return std::make_tuple(ret, 0);
	}
	}
	return std::make_tuple(ret, displays_.size());
	}

	bool DrmDevice::HandlesDisplay(int display) const {
	return displays_.find(display) != displays_.end();
	}

	DrmConnector *DrmDevice::GetConnectorForDisplay(int display) const {
	for (const auto &conn : connectors_) {
	if (conn->display() == display)
	return conn.get();
	}
	return nullptr;
	}

	DrmCrtc *DrmDevice::GetCrtcForDisplay(int display) const {
	for (const auto &crtc : crtcs_) {
	if (crtc->display() == display)
	return crtc.get();
	}
	return nullptr;
	}

	const std::vector<std::unique_ptr<DrmCrtc>> &DrmDevice::crtcs() const {
	return crtcs_;
	}

	uint32_t DrmDevice::next_mode_id() {
	return ++mode_id_;
	}

	int DrmDevice::TryEncoderForDisplay(int display, DrmEncoder *enc) {
	/* First try to use the currently-bound crtc */
	DrmCrtc *crtc = enc->crtc();
	if (crtc && crtc->can_bind(display)) {
	crtc->set_display(display);
	enc->set_crtc(crtc);
	return 0;
	}

	/* Try to find a possible crtc which will work */
	for (DrmCrtc *crtc : enc->possible_crtcs()) {
	/* We've already tried this earlier */
	if (crtc == enc->crtc())
	continue;

	if (crtc->can_bind(display)) {
	crtc->set_display(display);
	enc->set_crtc(crtc);
	return 0;
	}
	}

	/* We can't use the encoder, but nothing went wrong, try another one */
	return -EAGAIN;
	}

	int DrmDevice::CreateDisplayPipe(DrmConnector *connector) {
	int display = connector->display();
	/* Try to use current setup first */
	if (connector->encoder()) {
	int ret = TryEncoderForDisplay(display, connector->encoder());
	if (!ret) {
	return 0;
	}

	if (ret != -EAGAIN) {
	ALOGE("Could not set mode %d/%d", display, ret);
	return ret;
	}
	}

	for (DrmEncoder *enc : connector->possible_encoders()) {
	int ret = TryEncoderForDisplay(display, enc);
	if (!ret) {
	connector->set_encoder(enc);
	return 0;
	}

	if (ret != -EAGAIN) {
	ALOGE("Could not set mode %d/%d", display, ret);
	return ret;
	}
	}
	ALOGE("Could not find a suitable encoder/crtc for display %d",
	connector->display());
	return -ENODEV;
	}

	auto DrmDevice::RegisterUserPropertyBlob(void *data, size_t length) const
	-> DrmModeUserPropertyBlobUnique {
	struct drm_mode_create_blob create_blob {};
	create_blob.length = length;
	create_blob.data = (__u64)data;

	int ret = drmIoctl(fd(), DRM_IOCTL_MODE_CREATEPROPBLOB, &create_blob);
	if (ret) {
	ALOGE("Failed to create mode property blob %d", ret);
	return {};
	}

	return DrmModeUserPropertyBlobUnique(
	new uint32_t(create_blob.blob_id), [this](const uint32_t *it) {
	struct drm_mode_destroy_blob destroy_blob {};
	destroy_blob.blob_id = (__u32)*it;
	int err = drmIoctl(fd(), DRM_IOCTL_MODE_DESTROYPROPBLOB, &destroy_blob);
	if (err != 0) {
	ALOGE("Failed to destroy mode property blob %" PRIu32 "/%d", *it,
	err);
	}
	// NOLINTNEXTLINE(cppcoreguidelines-owning-memory)
	delete it;
	});
	}

	int DrmDevice::GetProperty(uint32_t obj_id, uint32_t obj_type,
	const char prop_name, DrmProperty property) const {
	drmModeObjectPropertiesPtr props = nullptr;

	props = drmModeObjectGetProperties(fd(), obj_id, obj_type);
	if (!props) {
	ALOGE("Failed to get properties for %d/%x", obj_id, obj_type);
	return -ENODEV;
	}

	bool found = false;
	for (int i = 0; !found && (size_t)i < props->count_props; ++i) {
	drmModePropertyPtr p = drmModeGetProperty(fd(), props->props[i]);
	if (!strcmp(p->name, prop_name)) {
	property->Init(obj_id, p, props->prop_values[i]);
	found = true;
	}
	drmModeFreeProperty(p);
	}

	drmModeFreeObjectProperties(props);
	return found ? 0 : -ENOENT;
	}

	int DrmDevice::GetCrtcProperty(const DrmCrtc &crtc, const char *prop_name,
	DrmProperty *property) const {
	return GetProperty(crtc.id(), DRM_MODE_OBJECT_CRTC, prop_name, property);
	}

	int DrmDevice::GetConnectorProperty(const DrmConnector &connector,
	const char *prop_name,
	DrmProperty *property) const {
	return GetProperty(connector.id(), DRM_MODE_OBJECT_CONNECTOR, prop_name,
	property);
	}

	std::string DrmDevice::GetName() const {
	auto *ver = drmGetVersion(fd());
	if (!ver) {
	ALOGW("Failed to get drm version for fd=%d", fd());
	return "generic";
	}

	std::string name(ver->name);
	drmFreeVersion(ver);
	return name;
	}

	auto DrmDevice::IsKMSDev(const char *path) -> bool {
	auto fd = UniqueFd(open(path, O_RDWR \| O_CLOEXEC));
	if (!fd) {
	return false;
	}

	auto res = MakeDrmModeResUnique(fd.Get());
	if (!res) {
	return false;
	}

	bool is_kms = res->count_crtcs > 0 && res->count_connectors > 0 &&
	res->count_encoders > 0;

	return is_kms;
	}

	} // namespace android