// 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.
// Note: ported from Chromium commit head: 2f13d62f0c0d
// Note: Added some missing defines that are only defined in newer kernel
// versions (e.g. V4L2_PIX_FMT_VP8_FRAME)
//#define LOG_NDEBUG 0
#define LOG_TAG "V4L2Device"
#include <v4l2_codec2/common/V4L2Device.h>
#include <fcntl.h>
#include <inttypes.h>
#include <linux/media.h>
#include <linux/videodev2.h>
#include <poll.h>
#include <string.h>
#include <sys/eventfd.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <algorithm>
#include <mutex>
#include <set>
#include <sstream>
#include <base/bind.h>
#include <base/numerics/safe_conversions.h>
#include <base/posix/eintr_wrapper.h>
#include <base/strings/stringprintf.h>
#include <base/thread_annotations.h>
#include <utils/Log.h>
#include <v4l2_codec2/common/Fourcc.h>
#include <v4l2_codec2/common/VideoPixelFormat.h>
// VP8 parsed frames
#ifndef V4L2_PIX_FMT_VP8_FRAME
#define V4L2_PIX_FMT_VP8_FRAME v4l2_fourcc('V', 'P', '8', 'F')
#endif
// VP9 parsed frames
#ifndef V4L2_PIX_FMT_VP9_FRAME
#define V4L2_PIX_FMT_VP9_FRAME v4l2_fourcc('V', 'P', '9', 'F')
#endif
// H264 parsed slices
#ifndef V4L2_PIX_FMT_H264_SLICE
#define V4L2_PIX_FMT_H264_SLICE v4l2_fourcc('S', '2', '6', '4')
#endif
namespace android {
struct v4l2_format buildV4L2Format(const enum v4l2_buf_type type, uint32_t fourcc,
const ui::Size& size, size_t buffer_size, uint32_t stride) {
struct v4l2_format format;
memset(&format, 0, sizeof(format));
format.type = type;
format.fmt.pix_mp.pixelformat = fourcc;
format.fmt.pix_mp.width = size.width;
format.fmt.pix_mp.height = size.height;
format.fmt.pix_mp.num_planes = V4L2Device::getNumPlanesOfV4L2PixFmt(fourcc);
format.fmt.pix_mp.plane_fmt[0].sizeimage = buffer_size;
// When the image format is planar the bytesperline value applies to the first plane and is
// divided by the same factor as the width field for the other planes.
format.fmt.pix_mp.plane_fmt[0].bytesperline = stride;
return format;
}
V4L2ExtCtrl::V4L2ExtCtrl(uint32_t id) {
memset(&ctrl, 0, sizeof(ctrl));
ctrl.id = id;
}
V4L2ExtCtrl::V4L2ExtCtrl(uint32_t id, int32_t val) : V4L2ExtCtrl(id) {
ctrl.value = val;
}
// Class used to store the state of a buffer that should persist between reference creations. This
// includes:
// * Result of initial VIDIOC_QUERYBUF ioctl,
// * Plane mappings.
//
// Also provides helper functions.
class V4L2Buffer {
public:
static std::unique_ptr<V4L2Buffer> create(scoped_refptr<V4L2Device> device,
enum v4l2_buf_type type, enum v4l2_memory memory,
const struct v4l2_format& format, size_t bufferId);
~V4L2Buffer();
V4L2Buffer(const V4L2Buffer&) = delete;
V4L2Buffer& operator=(const V4L2Buffer&) = delete;
void* getPlaneMapping(const size_t plane);
size_t getMemoryUsage() const;
const struct v4l2_buffer& v4l2_buffer() const { return mV4l2Buffer; }
private:
V4L2Buffer(scoped_refptr<V4L2Device> device, enum v4l2_buf_type type, enum v4l2_memory memory,
const struct v4l2_format& format, size_t bufferId);
bool query();
scoped_refptr<V4L2Device> mDevice;
std::vector<void*> mPlaneMappings;
// V4L2 data as queried by QUERYBUF.
struct v4l2_buffer mV4l2Buffer;
// WARNING: do not change this to a vector or something smaller than VIDEO_MAX_PLANES, otherwise
// the Tegra libv4l2 will write data beyond the number of allocated planes, resulting in memory
// corruption.
struct v4l2_plane mV4l2Planes[VIDEO_MAX_PLANES];
struct v4l2_format mFormat __attribute__((unused));
};
std::unique_ptr<V4L2Buffer> V4L2Buffer::create(scoped_refptr<V4L2Device> device,
enum v4l2_buf_type type, enum v4l2_memory memory,
const struct v4l2_format& format, size_t bufferId) {
// Not using std::make_unique because constructor is private.
std::unique_ptr<V4L2Buffer> buffer(new V4L2Buffer(device, type, memory, format, bufferId));
if (!buffer->query()) return nullptr;
return buffer;
}
V4L2Buffer::V4L2Buffer(scoped_refptr<V4L2Device> device, enum v4l2_buf_type type,
enum v4l2_memory memory, const struct v4l2_format& format, size_t bufferId)
: mDevice(device), mFormat(format) {
ALOG_ASSERT(V4L2_TYPE_IS_MULTIPLANAR(type));
ALOG_ASSERT(format.fmt.pix_mp.num_planes <= base::size(mV4l2Planes));
memset(mV4l2Planes, 0, sizeof(mV4l2Planes));
memset(&mV4l2Buffer, 0, sizeof(mV4l2Buffer));
mV4l2Buffer.m.planes = mV4l2Planes;
// Just in case we got more planes than we want.
mV4l2Buffer.length =
std::min(static_cast<size_t>(format.fmt.pix_mp.num_planes), base::size(mV4l2Planes));
mV4l2Buffer.index = bufferId;
mV4l2Buffer.type = type;
mV4l2Buffer.memory = memory;
mV4l2Buffer.memory = V4L2_MEMORY_DMABUF;
mPlaneMappings.resize(mV4l2Buffer.length);
}
V4L2Buffer::~V4L2Buffer() {
if (mV4l2Buffer.memory == V4L2_MEMORY_MMAP) {
for (size_t i = 0; i < mPlaneMappings.size(); i++) {
if (mPlaneMappings[i] != nullptr) {
mDevice->munmap(mPlaneMappings[i], mV4l2Buffer.m.planes[i].length);
}
}
}
}
bool V4L2Buffer::query() {
int ret = mDevice->ioctl(VIDIOC_QUERYBUF, &mV4l2Buffer);
if (ret) {
ALOGE("VIDIOC_QUERYBUF failed");
return false;
}
DCHECK(mPlaneMappings.size() == mV4l2Buffer.length);
return true;
}
void* V4L2Buffer::getPlaneMapping(const size_t plane) {
if (plane >= mPlaneMappings.size()) {
ALOGE("Invalid plane %zu requested.", plane);
return nullptr;
}
void* p = mPlaneMappings[plane];
if (p) {
return p;
}
// Do this check here to avoid repeating it after a buffer has been successfully mapped (we know
// we are of MMAP type by then).
if (mV4l2Buffer.memory != V4L2_MEMORY_MMAP) {
ALOGE("Cannot create mapping on non-MMAP buffer");
return nullptr;
}
p = mDevice->mmap(NULL, mV4l2Buffer.m.planes[plane].length, PROT_READ | PROT_WRITE, MAP_SHARED,
mV4l2Buffer.m.planes[plane].m.mem_offset);
if (p == MAP_FAILED) {
ALOGE("mmap() failed: ");
return nullptr;
}
mPlaneMappings[plane] = p;
return p;
}
size_t V4L2Buffer::getMemoryUsage() const {
size_t usage = 0;
for (size_t i = 0; i < mV4l2Buffer.length; i++) {
usage += mV4l2Buffer.m.planes[i].length;
}
return usage;
}
// A thread-safe pool of buffer indexes, allowing buffers to be obtained and returned from different
// threads. All the methods of this class are thread-safe. Users should keep a scoped_refptr to
// instances of this class in order to ensure the list remains alive as long as they need it.
class V4L2BuffersList : public base::RefCountedThreadSafe<V4L2BuffersList> {
public:
V4L2BuffersList() = default;
V4L2BuffersList(const V4L2BuffersList&) = delete;
V4L2BuffersList& operator=(const V4L2BuffersList&) = delete;
// Return a buffer to this list. Also can be called to set the initial pool of buffers.
// Note that it is illegal to return the same buffer twice.
void returnBuffer(size_t bufferId);
// Get any of the buffers in the list. There is no order guarantee whatsoever.
std::optional<size_t> getFreeBuffer();
// Get the buffer with specified index.
std::optional<size_t> getFreeBuffer(size_t requestedBufferId);
// Number of buffers currently in this list.
size_t size() const;
private:
friend class base::RefCountedThreadSafe<V4L2BuffersList>;
~V4L2BuffersList() = default;
mutable std::mutex mLock;
std::set<size_t> mFreeBuffers GUARDED_BY(mLock);
};
void V4L2BuffersList::returnBuffer(size_t bufferId) {
std::lock_guard<std::mutex> lock(mLock);
auto inserted = mFreeBuffers.emplace(bufferId);
if (!inserted.second) {
ALOGE("Returning buffer failed");
}
}
std::optional<size_t> V4L2BuffersList::getFreeBuffer() {
std::lock_guard<std::mutex> lock(mLock);
auto iter = mFreeBuffers.begin();
if (iter == mFreeBuffers.end()) {
ALOGV("No free buffer available!");
return std::nullopt;
}
size_t bufferId = *iter;
mFreeBuffers.erase(iter);
return bufferId;
}
std::optional<size_t> V4L2BuffersList::getFreeBuffer(size_t requestedBufferId) {
std::lock_guard<std::mutex> lock(mLock);
return (mFreeBuffers.erase(requestedBufferId) > 0) ? std::make_optional(requestedBufferId)
: std::nullopt;
}
size_t V4L2BuffersList::size() const {
std::lock_guard<std::mutex> lock(mLock);
return mFreeBuffers.size();
}
// Module-private class that let users query/write V4L2 buffer information. It also makes some
// private V4L2Queue methods available to this module only.
class V4L2BufferRefBase {
public:
V4L2BufferRefBase(const struct v4l2_buffer& v4l2Buffer, base::WeakPtr<V4L2Queue> queue);
~V4L2BufferRefBase();
V4L2BufferRefBase(const V4L2BufferRefBase&) = delete;
V4L2BufferRefBase& operator=(const V4L2BufferRefBase&) = delete;
bool queueBuffer();
void* getPlaneMapping(const size_t plane);
// Checks that the number of passed FDs is adequate for the current format and buffer
// configuration. Only useful for DMABUF buffers.
bool checkNumFDsForFormat(const size_t numFds) const;
// Data from the buffer, that users can query and/or write.
struct v4l2_buffer mV4l2Buffer;
// WARNING: do not change this to a vector or something smaller than VIDEO_MAX_PLANES, otherwise
// the Tegra libv4l2 will write data beyond the number of allocated planes, resulting in memory
// corruption.
struct v4l2_plane mV4l2Planes[VIDEO_MAX_PLANES];
private:
size_t bufferId() const { return mV4l2Buffer.index; }
friend class V4L2WritableBufferRef;
// A weak pointer to the queue this buffer belongs to. Will remain valid as long as the
// underlying V4L2 buffer is valid too. This can only be accessed from the sequence protected by
// sequence_checker_. Thread-safe methods (like ~V4L2BufferRefBase) must *never* access this.
base::WeakPtr<V4L2Queue> mQueue;
// Where to return this buffer if it goes out of scope without being queued.
scoped_refptr<V4L2BuffersList> mReturnTo;
bool queued = false;
SEQUENCE_CHECKER(mSequenceChecker);
};
V4L2BufferRefBase::V4L2BufferRefBase(const struct v4l2_buffer& v4l2Buffer,
base::WeakPtr<V4L2Queue> queue)
: mQueue(std::move(queue)), mReturnTo(mQueue->mFreeBuffers) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(V4L2_TYPE_IS_MULTIPLANAR(v4l2Buffer.type));
ALOG_ASSERT(v4l2Buffer.length <= base::size(mV4l2Planes));
ALOG_ASSERT(mReturnTo);
memcpy(&mV4l2Buffer, &v4l2Buffer, sizeof(mV4l2Buffer));
memcpy(mV4l2Planes, v4l2Buffer.m.planes, sizeof(struct v4l2_plane) * v4l2Buffer.length);
mV4l2Buffer.m.planes = mV4l2Planes;
}
V4L2BufferRefBase::~V4L2BufferRefBase() {
// We are the last reference and are only accessing the thread-safe mReturnTo, so we are safe
// to call from any sequence. If we have been queued, then the queue is our owner so we don't
// need to return to the free buffers list.
if (!queued) mReturnTo->returnBuffer(bufferId());
}
bool V4L2BufferRefBase::queueBuffer() {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
if (!mQueue) return false;
queued = mQueue->queueBuffer(&mV4l2Buffer);
return queued;
}
void* V4L2BufferRefBase::getPlaneMapping(const size_t plane) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
if (!mQueue) return nullptr;
return mQueue->mBuffers[bufferId()]->getPlaneMapping(plane);
}
bool V4L2BufferRefBase::checkNumFDsForFormat(const size_t numFds) const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
if (!mQueue) return false;
// We have not used SetFormat(), assume this is ok.
// Hopefully we standardize SetFormat() in the future.
if (!mQueue->mCurrentFormat) return true;
const size_t requiredFds = mQueue->mCurrentFormat->fmt.pix_mp.num_planes;
// Sanity check.
ALOG_ASSERT(mV4l2Buffer.length == requiredFds);
if (numFds < requiredFds) {
ALOGE("Insufficient number of FDs given for the current format. "
"%zu provided, %zu required.",
numFds, requiredFds);
return false;
}
const auto* planes = mV4l2Buffer.m.planes;
for (size_t i = mV4l2Buffer.length - 1; i >= numFds; --i) {
// Assume that an fd is a duplicate of a previous plane's fd if offset != 0. Otherwise, if
// offset == 0, return error as it is likely pointing to a new plane.
if (planes[i].data_offset == 0) {
ALOGE("Additional dmabuf fds point to a new buffer.");
return false;
}
}
return true;
}
V4L2WritableBufferRef::V4L2WritableBufferRef(const struct v4l2_buffer& v4l2Buffer,
base::WeakPtr<V4L2Queue> queue)
: mBufferData(std::make_unique<V4L2BufferRefBase>(v4l2Buffer, std::move(queue))) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
}
V4L2WritableBufferRef::V4L2WritableBufferRef(V4L2WritableBufferRef&& other)
: mBufferData(std::move(other.mBufferData)) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
DCHECK_CALLED_ON_VALID_SEQUENCE(other.mSequenceChecker);
}
V4L2WritableBufferRef::~V4L2WritableBufferRef() {
// Only valid references should be sequence-checked
if (mBufferData) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
}
}
V4L2WritableBufferRef& V4L2WritableBufferRef::operator=(V4L2WritableBufferRef&& other) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
DCHECK_CALLED_ON_VALID_SEQUENCE(other.mSequenceChecker);
if (this == &other) return *this;
mBufferData = std::move(other.mBufferData);
return *this;
}
enum v4l2_memory V4L2WritableBufferRef::memory() const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
return static_cast<enum v4l2_memory>(mBufferData->mV4l2Buffer.memory);
}
bool V4L2WritableBufferRef::doQueue() && {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
bool queued = mBufferData->queueBuffer();
// Clear our own reference.
mBufferData.reset();
return queued;
}
bool V4L2WritableBufferRef::queueMMap() && {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
// Move ourselves so our data gets freed no matter when we return
V4L2WritableBufferRef self(std::move(*this));
if (self.memory() != V4L2_MEMORY_MMAP) {
ALOGE("Called on invalid buffer type!");
return false;
}
return std::move(self).doQueue();
}
bool V4L2WritableBufferRef::queueUserPtr(const std::vector<void*>& ptrs) && {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
// Move ourselves so our data gets freed no matter when we return
V4L2WritableBufferRef self(std::move(*this));
if (self.memory() != V4L2_MEMORY_USERPTR) {
ALOGE("Called on invalid buffer type!");
return false;
}
if (ptrs.size() != self.planesCount()) {
ALOGE("Provided %zu pointers while we require %u.", ptrs.size(),
self.mBufferData->mV4l2Buffer.length);
return false;
}
for (size_t i = 0; i < ptrs.size(); i++) {
self.mBufferData->mV4l2Buffer.m.planes[i].m.userptr =
reinterpret_cast<unsigned long>(ptrs[i]);
}
return std::move(self).doQueue();
}
bool V4L2WritableBufferRef::queueDMABuf(const std::vector<int>& fds) && {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
// Move ourselves so our data gets freed no matter when we return
V4L2WritableBufferRef self(std::move(*this));
if (self.memory() != V4L2_MEMORY_DMABUF) {
ALOGE("Called on invalid buffer type!");
return false;
}
if (!self.mBufferData->checkNumFDsForFormat(fds.size())) return false;
size_t numPlanes = self.planesCount();
for (size_t i = 0; i < numPlanes; i++) self.mBufferData->mV4l2Buffer.m.planes[i].m.fd = fds[i];
return std::move(self).doQueue();
}
size_t V4L2WritableBufferRef::planesCount() const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
return mBufferData->mV4l2Buffer.length;
}
size_t V4L2WritableBufferRef::getPlaneSize(const size_t plane) const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
if (plane >= planesCount()) {
ALOGE("Invalid plane %zu requested.", plane);
return 0;
}
return mBufferData->mV4l2Buffer.m.planes[plane].length;
}
void V4L2WritableBufferRef::setPlaneSize(const size_t plane, const size_t size) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
enum v4l2_memory mem = memory();
if (mem == V4L2_MEMORY_MMAP) {
ALOG_ASSERT(mBufferData->mV4l2Buffer.m.planes[plane].length == size);
return;
}
ALOG_ASSERT(mem == V4L2_MEMORY_USERPTR || mem == V4L2_MEMORY_DMABUF);
if (plane >= planesCount()) {
ALOGE("Invalid plane %zu requested.", plane);
return;
}
mBufferData->mV4l2Buffer.m.planes[plane].length = size;
}
void* V4L2WritableBufferRef::getPlaneMapping(const size_t plane) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
return mBufferData->getPlaneMapping(plane);
}
void V4L2WritableBufferRef::setTimeStamp(const struct timeval& timestamp) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
mBufferData->mV4l2Buffer.timestamp = timestamp;
}
const struct timeval& V4L2WritableBufferRef::getTimeStamp() const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
return mBufferData->mV4l2Buffer.timestamp;
}
void V4L2WritableBufferRef::setPlaneBytesUsed(const size_t plane, const size_t bytesUsed) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
if (plane >= planesCount()) {
ALOGE("Invalid plane %zu requested.", plane);
return;
}
if (bytesUsed > getPlaneSize(plane)) {
ALOGE("Set bytes used %zu larger than plane size %zu.", bytesUsed, getPlaneSize(plane));
return;
}
mBufferData->mV4l2Buffer.m.planes[plane].bytesused = bytesUsed;
}
size_t V4L2WritableBufferRef::getPlaneBytesUsed(const size_t plane) const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
if (plane >= planesCount()) {
ALOGE("Invalid plane %zu requested.", plane);
return 0;
}
return mBufferData->mV4l2Buffer.m.planes[plane].bytesused;
}
void V4L2WritableBufferRef::setPlaneDataOffset(const size_t plane, const size_t dataOffset) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
if (plane >= planesCount()) {
ALOGE("Invalid plane %zu requested.", plane);
return;
}
mBufferData->mV4l2Buffer.m.planes[plane].data_offset = dataOffset;
}
size_t V4L2WritableBufferRef::bufferId() const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
return mBufferData->mV4l2Buffer.index;
}
V4L2ReadableBuffer::V4L2ReadableBuffer(const struct v4l2_buffer& v4l2Buffer,
base::WeakPtr<V4L2Queue> queue)
: mBufferData(std::make_unique<V4L2BufferRefBase>(v4l2Buffer, std::move(queue))) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
}
V4L2ReadableBuffer::~V4L2ReadableBuffer() {
// This method is thread-safe. Since we are the destructor, we are guaranteed to be called from
// the only remaining reference to us. Also, we are just calling the destructor of buffer_data_,
// which is also thread-safe.
ALOG_ASSERT(mBufferData);
}
bool V4L2ReadableBuffer::isLast() const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
return mBufferData->mV4l2Buffer.flags & V4L2_BUF_FLAG_LAST;
}
bool V4L2ReadableBuffer::isKeyframe() const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
return mBufferData->mV4l2Buffer.flags & V4L2_BUF_FLAG_KEYFRAME;
}
struct timeval V4L2ReadableBuffer::getTimeStamp() const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
return mBufferData->mV4l2Buffer.timestamp;
}
size_t V4L2ReadableBuffer::planesCount() const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
return mBufferData->mV4l2Buffer.length;
}
const void* V4L2ReadableBuffer::getPlaneMapping(const size_t plane) const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
DCHECK(mBufferData);
return mBufferData->getPlaneMapping(plane);
}
size_t V4L2ReadableBuffer::getPlaneBytesUsed(const size_t plane) const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
if (plane >= planesCount()) {
ALOGE("Invalid plane %zu requested.", plane);
return 0;
}
return mBufferData->mV4l2Planes[plane].bytesused;
}
size_t V4L2ReadableBuffer::getPlaneDataOffset(const size_t plane) const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
if (plane >= planesCount()) {
ALOGE("Invalid plane %zu requested.", plane);
return 0;
}
return mBufferData->mV4l2Planes[plane].data_offset;
}
size_t V4L2ReadableBuffer::bufferId() const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(mBufferData);
return mBufferData->mV4l2Buffer.index;
}
// This class is used to expose buffer reference classes constructors to this module. This is to
// ensure that nobody else can create buffer references.
class V4L2BufferRefFactory {
public:
static V4L2WritableBufferRef CreateWritableRef(const struct v4l2_buffer& v4l2Buffer,
base::WeakPtr<V4L2Queue> queue) {
return V4L2WritableBufferRef(v4l2Buffer, std::move(queue));
}
static V4L2ReadableBufferRef CreateReadableRef(const struct v4l2_buffer& v4l2Buffer,
base::WeakPtr<V4L2Queue> queue) {
return new V4L2ReadableBuffer(v4l2Buffer, std::move(queue));
}
};
//// Helper macros that print the queue type with logs.
#define ALOGEQ(fmt, ...) ALOGE("(%s)" fmt, V4L2Device::v4L2BufferTypeToString(mType), ##__VA_ARGS__)
#define ALOGVQ(fmt, ...) ALOGD("(%s)" fmt, V4L2Device::v4L2BufferTypeToString(mType), ##__VA_ARGS__)
V4L2Queue::V4L2Queue(scoped_refptr<V4L2Device> dev, enum v4l2_buf_type type,
base::OnceClosure destroyCb)
: mType(type), mDevice(dev), mDestroyCb(std::move(destroyCb)) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
}
V4L2Queue::~V4L2Queue() {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
if (mIsStreaming) {
ALOGEQ("Queue is still streaming, trying to stop it...");
streamoff();
}
ALOG_ASSERT(mQueuedBuffers.empty());
ALOG_ASSERT(!mFreeBuffers);
if (!mBuffers.empty()) {
ALOGEQ("Buffers are still allocated, trying to deallocate them...");
deallocateBuffers();
}
std::move(mDestroyCb).Run();
}
std::optional<struct v4l2_format> V4L2Queue::setFormat(uint32_t fourcc, const ui::Size& size,
size_t bufferSize, uint32_t stride) {
struct v4l2_format format = buildV4L2Format(mType, fourcc, size, bufferSize, stride);
if (mDevice->ioctl(VIDIOC_S_FMT, &format) != 0 || format.fmt.pix_mp.pixelformat != fourcc) {
ALOGEQ("Failed to set format (format_fourcc=0x%" PRIx32 ")", fourcc);
return std::nullopt;
}
mCurrentFormat = format;
return mCurrentFormat;
}
std::optional<struct v4l2_format> V4L2Queue::tryFormat(uint32_t fourcc, const ui::Size& size,
size_t bufferSize) {
struct v4l2_format format = buildV4L2Format(mType, fourcc, size, bufferSize, 0);
if (mDevice->ioctl(VIDIOC_TRY_FMT, &format) != 0 || format.fmt.pix_mp.pixelformat != fourcc) {
ALOGEQ("Tried format not supported (format_fourcc=0x%" PRIx32 ")", fourcc);
return std::nullopt;
}
return format;
}
std::pair<std::optional<struct v4l2_format>, int> V4L2Queue::getFormat() {
struct v4l2_format format;
memset(&format, 0, sizeof(format));
format.type = mType;
if (mDevice->ioctl(VIDIOC_G_FMT, &format) != 0) {
ALOGEQ("Failed to get format");
return std::make_pair(std::nullopt, errno);
}
return std::make_pair(format, 0);
}
size_t V4L2Queue::allocateBuffers(size_t count, enum v4l2_memory memory) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
ALOG_ASSERT(!mFreeBuffers);
ALOG_ASSERT(mQueuedBuffers.size() == 0u);
if (isStreaming()) {
ALOGEQ("Cannot allocate buffers while streaming.");
return 0;
}
if (mBuffers.size() != 0) {
ALOGEQ("Cannot allocate new buffers while others are still allocated.");
return 0;
}
if (count == 0) {
ALOGEQ("Attempting to allocate 0 buffers.");
return 0;
}
// First query the number of planes in the buffers we are about to request. This should not be
// required, but Tegra's VIDIOC_QUERYBUF will fail on output buffers if the number of specified
// planes does not exactly match the format.
struct v4l2_format format = {.type = mType};
int ret = mDevice->ioctl(VIDIOC_G_FMT, &format);
if (ret) {
ALOGEQ("VIDIOC_G_FMT failed");
return 0;
}
mPlanesCount = format.fmt.pix_mp.num_planes;
ALOG_ASSERT(mPlanesCount <= static_cast<size_t>(VIDEO_MAX_PLANES));
struct v4l2_requestbuffers reqbufs;
memset(&reqbufs, 0, sizeof(reqbufs));
reqbufs.count = count;
reqbufs.type = mType;
reqbufs.memory = memory;
ALOGVQ("Requesting %zu buffers.", count);
ret = mDevice->ioctl(VIDIOC_REQBUFS, &reqbufs);
if (ret) {
ALOGEQ("VIDIOC_REQBUFS failed");
return 0;
}
ALOGVQ("Queue %u: got %u buffers.", mType, reqbufs.count);
mMemory = memory;
mFreeBuffers = new V4L2BuffersList();
// Now query all buffer information.
for (size_t i = 0; i < reqbufs.count; i++) {
auto buffer = V4L2Buffer::create(mDevice, mType, mMemory, format, i);
if (!buffer) {
deallocateBuffers();
return 0;
}
mBuffers.emplace_back(std::move(buffer));
mFreeBuffers->returnBuffer(i);
}
ALOG_ASSERT(mFreeBuffers);
ALOG_ASSERT(mFreeBuffers->size() == mBuffers.size());
ALOG_ASSERT(mQueuedBuffers.size() == 0u);
return mBuffers.size();
}
bool V4L2Queue::deallocateBuffers() {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
if (isStreaming()) {
ALOGEQ("Cannot deallocate buffers while streaming.");
return false;
}
if (mBuffers.size() == 0) return true;
mWeakThisFactory.InvalidateWeakPtrs();
mBuffers.clear();
mFreeBuffers = nullptr;
// Free all buffers.
struct v4l2_requestbuffers reqbufs;
memset(&reqbufs, 0, sizeof(reqbufs));
reqbufs.count = 0;
reqbufs.type = mType;
reqbufs.memory = mMemory;
int ret = mDevice->ioctl(VIDIOC_REQBUFS, &reqbufs);
if (ret) {
ALOGEQ("VIDIOC_REQBUFS failed");
return false;
}
ALOG_ASSERT(!mFreeBuffers);
ALOG_ASSERT(mQueuedBuffers.size() == 0u);
return true;
}
size_t V4L2Queue::getMemoryUsage() const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
size_t usage = 0;
for (const auto& buf : mBuffers) {
usage += buf->getMemoryUsage();
}
return usage;
}
v4l2_memory V4L2Queue::getMemoryType() const {
return mMemory;
}
std::optional<V4L2WritableBufferRef> V4L2Queue::getFreeBuffer() {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
// No buffers allocated at the moment?
if (!mFreeBuffers) return std::nullopt;
auto bufferId = mFreeBuffers->getFreeBuffer();
if (!bufferId.has_value()) return std::nullopt;
return V4L2BufferRefFactory::CreateWritableRef(mBuffers[bufferId.value()]->v4l2_buffer(),
mWeakThisFactory.GetWeakPtr());
}
std::optional<V4L2WritableBufferRef> V4L2Queue::getFreeBuffer(size_t requestedBufferIid) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
// No buffers allocated at the moment?
if (!mFreeBuffers) return std::nullopt;
auto bufferId = mFreeBuffers->getFreeBuffer(requestedBufferIid);
if (!bufferId.has_value()) return std::nullopt;
return V4L2BufferRefFactory::CreateWritableRef(mBuffers[bufferId.value()]->v4l2_buffer(),
mWeakThisFactory.GetWeakPtr());
}
bool V4L2Queue::queueBuffer(struct v4l2_buffer* v4l2Buffer) {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
int ret = mDevice->ioctl(VIDIOC_QBUF, v4l2Buffer);
if (ret) {
ALOGEQ("VIDIOC_QBUF failed");
return false;
}
auto inserted = mQueuedBuffers.emplace(v4l2Buffer->index);
if (!inserted.second) {
ALOGE("Queuing buffer failed");
return false;
}
mDevice->schedulePoll();
return true;
}
std::pair<bool, V4L2ReadableBufferRef> V4L2Queue::dequeueBuffer() {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
// No need to dequeue if no buffers queued.
if (queuedBuffersCount() == 0) return std::make_pair(true, nullptr);
if (!isStreaming()) {
ALOGEQ("Attempting to dequeue a buffer while not streaming.");
return std::make_pair(true, nullptr);
}
struct v4l2_buffer v4l2Buffer;
memset(&v4l2Buffer, 0, sizeof(v4l2Buffer));
// WARNING: do not change this to a vector or something smaller than VIDEO_MAX_PLANES, otherwise
// the Tegra libv4l2 will write data beyond the number of allocated planes, resulting in memory
// corruption.
struct v4l2_plane planes[VIDEO_MAX_PLANES];
memset(planes, 0, sizeof(planes));
v4l2Buffer.type = mType;
v4l2Buffer.memory = mMemory;
v4l2Buffer.m.planes = planes;
v4l2Buffer.length = mPlanesCount;
int ret = mDevice->ioctl(VIDIOC_DQBUF, &v4l2Buffer);
if (ret) {
// TODO(acourbot): we should not have to check for EPIPE as codec clients should not call
// this method after the last buffer is dequeued.
switch (errno) {
case EAGAIN:
case EPIPE:
// This is not an error so we'll need to continue polling but won't provide a buffer.
mDevice->schedulePoll();
return std::make_pair(true, nullptr);
default:
ALOGEQ("VIDIOC_DQBUF failed");
return std::make_pair(false, nullptr);
}
}
auto it = mQueuedBuffers.find(v4l2Buffer.index);
ALOG_ASSERT(it != mQueuedBuffers.end());
mQueuedBuffers.erase(*it);
if (queuedBuffersCount() > 0) mDevice->schedulePoll();
ALOG_ASSERT(mFreeBuffers);
return std::make_pair(true, V4L2BufferRefFactory::CreateReadableRef(
v4l2Buffer, mWeakThisFactory.GetWeakPtr()));
}
bool V4L2Queue::isStreaming() const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
return mIsStreaming;
}
bool V4L2Queue::streamon() {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
if (mIsStreaming) return true;
int arg = static_cast<int>(mType);
int ret = mDevice->ioctl(VIDIOC_STREAMON, &arg);
if (ret) {
ALOGEQ("VIDIOC_STREAMON failed");
return false;
}
mIsStreaming = true;
return true;
}
bool V4L2Queue::streamoff() {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
// We do not check the value of IsStreaming(), because we may have queued buffers to the queue
// and wish to get them back - in such as case, we may need to do a VIDIOC_STREAMOFF on a
// stopped queue.
int arg = static_cast<int>(mType);
int ret = mDevice->ioctl(VIDIOC_STREAMOFF, &arg);
if (ret) {
ALOGEQ("VIDIOC_STREAMOFF failed");
return false;
}
for (const auto& bufferId : mQueuedBuffers) {
ALOG_ASSERT(mFreeBuffers);
mFreeBuffers->returnBuffer(bufferId);
}
mQueuedBuffers.clear();
mIsStreaming = false;
return true;
}
size_t V4L2Queue::allocatedBuffersCount() const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
return mBuffers.size();
}
size_t V4L2Queue::freeBuffersCount() const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
return mFreeBuffers ? mFreeBuffers->size() : 0;
}
size_t V4L2Queue::queuedBuffersCount() const {
ALOG_ASSERT(mSequenceChecker.CalledOnValidSequence());
return mQueuedBuffers.size();
}
#undef ALOGEQ
#undef ALOGVQ
// This class is used to expose V4L2Queue's constructor to this module. This is to ensure that
// nobody else can create instances of it.
class V4L2QueueFactory {
public:
static scoped_refptr<V4L2Queue> createQueue(scoped_refptr<V4L2Device> dev,
enum v4l2_buf_type type,
base::OnceClosure destroyCb) {
return new V4L2Queue(std::move(dev), type, std::move(destroyCb));
}
};
V4L2Device::V4L2Device() {
DETACH_FROM_SEQUENCE(mClientSequenceChecker);
}
V4L2Device::~V4L2Device() {
closeDevice();
}
scoped_refptr<V4L2Queue> V4L2Device::getQueue(enum v4l2_buf_type type) {
DCHECK_CALLED_ON_VALID_SEQUENCE(mClientSequenceChecker);
switch (type) {
// Supported queue types.
case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
break;
default:
ALOGE("Unsupported V4L2 queue type: %u", type);
return nullptr;
}
// TODO(acourbot): we should instead query the device for available queues, and allocate them
// accordingly. This will do for now though.
auto it = mQueues.find(type);
if (it != mQueues.end()) return scoped_refptr<V4L2Queue>(it->second);
scoped_refptr<V4L2Queue> queue = V4L2QueueFactory::createQueue(
this, type, base::BindOnce(&V4L2Device::onQueueDestroyed, this, type));
mQueues[type] = queue.get();
return queue;
}
void V4L2Device::onQueueDestroyed(v4l2_buf_type bufType) {
DCHECK_CALLED_ON_VALID_SEQUENCE(mClientSequenceChecker);
auto it = mQueues.find(bufType);
ALOG_ASSERT(it != mQueues.end());
mQueues.erase(it);
}
// static
scoped_refptr<V4L2Device> V4L2Device::create() {
ALOGV("%s()", __func__);
return scoped_refptr<V4L2Device>(new V4L2Device());
}
bool V4L2Device::open(Type type, uint32_t v4l2PixFmt) {
ALOGV("%s()", __func__);
std::string path = getDevicePathFor(type, v4l2PixFmt);
if (path.empty()) {
ALOGE("No devices supporting %s for type: %u", fourccToString(v4l2PixFmt).c_str(),
static_cast<uint32_t>(type));
return false;
}
if (!openDevicePath(path, type)) {
ALOGE("Failed opening %s", path.c_str());
return false;
}
mDevicePollInterruptFd.reset(eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC));
if (!mDevicePollInterruptFd.is_valid()) {
ALOGE("Failed creating a poll interrupt fd");
return false;
}
return true;
}
int V4L2Device::ioctl(int request, void* arg) {
ALOG_ASSERT(mDeviceFd.is_valid());
return HANDLE_EINTR(::ioctl(mDeviceFd.get(), request, arg));
}
bool V4L2Device::poll(bool pollDevice, bool* eventPending) {
struct pollfd pollfds[2];
nfds_t nfds;
int pollfd = -1;
pollfds[0].fd = mDevicePollInterruptFd.get();
pollfds[0].events = POLLIN | POLLERR;
nfds = 1;
if (pollDevice) {
ALOGV("adding device fd to poll() set");
pollfds[nfds].fd = mDeviceFd.get();
pollfds[nfds].events = POLLIN | POLLOUT | POLLERR | POLLPRI;
pollfd = nfds;
nfds++;
}
if (HANDLE_EINTR(::poll(pollfds, nfds, -1)) == -1) {
ALOGE("poll() failed");
return false;
}
*eventPending = (pollfd != -1 && pollfds[pollfd].revents & POLLPRI);
return true;
}
void* V4L2Device::mmap(void* addr, unsigned int len, int prot, int flags, unsigned int offset) {
DCHECK(mDeviceFd.is_valid());
return ::mmap(addr, len, prot, flags, mDeviceFd.get(), offset);
}
void V4L2Device::munmap(void* addr, unsigned int len) {
::munmap(addr, len);
}
bool V4L2Device::setDevicePollInterrupt() {
ALOGV("%s()", __func__);
const uint64_t buf = 1;
if (HANDLE_EINTR(write(mDevicePollInterruptFd.get(), &buf, sizeof(buf))) == -1) {
ALOGE("write() failed");
return false;
}
return true;
}
bool V4L2Device::clearDevicePollInterrupt() {
ALOGV("%s()", __func__);
uint64_t buf;
if (HANDLE_EINTR(read(mDevicePollInterruptFd.get(), &buf, sizeof(buf))) == -1) {
if (errno == EAGAIN) {
// No interrupt flag set, and we're reading nonblocking. Not an error.
return true;
} else {
ALOGE("read() failed");
return false;
}
}
return true;
}
std::vector<base::ScopedFD> V4L2Device::getDmabufsForV4L2Buffer(int index, size_t numPlanes,
enum v4l2_buf_type bufType) {
ALOGV("%s()", __func__);
ALOG_ASSERT(V4L2_TYPE_IS_MULTIPLANAR(bufType));
std::vector<base::ScopedFD> dmabufFds;
for (size_t i = 0; i < numPlanes; ++i) {
struct v4l2_exportbuffer expbuf;
memset(&expbuf, 0, sizeof(expbuf));
expbuf.type = bufType;
expbuf.index = index;
expbuf.plane = i;
expbuf.flags = O_CLOEXEC;
if (ioctl(VIDIOC_EXPBUF, &expbuf) != 0) {
dmabufFds.clear();
break;
}
dmabufFds.push_back(base::ScopedFD(expbuf.fd));
}
return dmabufFds;
}
std::vector<uint32_t> V4L2Device::preferredInputFormat(Type type) {
if (type == Type::kEncoder) return {V4L2_PIX_FMT_NV12M, V4L2_PIX_FMT_NV12};
return {};
}
// static
uint32_t V4L2Device::C2ProfileToV4L2PixFmt(C2Config::profile_t profile, bool sliceBased) {
if (profile >= C2Config::PROFILE_AVC_BASELINE &&
profile <= C2Config::PROFILE_AVC_ENHANCED_MULTIVIEW_DEPTH_HIGH) {
if (sliceBased) {
return V4L2_PIX_FMT_H264_SLICE;
} else {
return V4L2_PIX_FMT_H264;
}
} else if (profile >= C2Config::PROFILE_VP8_0 && profile <= C2Config::PROFILE_VP8_3) {
if (sliceBased) {
return V4L2_PIX_FMT_VP8_FRAME;
} else {
return V4L2_PIX_FMT_VP8;
}
} else if (profile >= C2Config::PROFILE_VP9_0 && profile <= C2Config::PROFILE_VP9_3) {
if (sliceBased) {
return V4L2_PIX_FMT_VP9_FRAME;
} else {
return V4L2_PIX_FMT_VP9;
}
} else {
ALOGE("Unknown profile: %s", profileToString(profile));
return 0;
}
}
// static
C2Config::profile_t V4L2Device::v4L2ProfileToC2Profile(VideoCodec codec, uint32_t profile) {
switch (codec) {
case VideoCodec::H264:
switch (profile) {
case V4L2_MPEG_VIDEO_H264_PROFILE_BASELINE:
case V4L2_MPEG_VIDEO_H264_PROFILE_CONSTRAINED_BASELINE:
return C2Config::PROFILE_AVC_BASELINE;
case V4L2_MPEG_VIDEO_H264_PROFILE_MAIN:
return C2Config::PROFILE_AVC_MAIN;
case V4L2_MPEG_VIDEO_H264_PROFILE_EXTENDED:
return C2Config::PROFILE_AVC_EXTENDED;
case V4L2_MPEG_VIDEO_H264_PROFILE_HIGH:
return C2Config::PROFILE_AVC_HIGH;
}
break;
case VideoCodec::VP8:
switch (profile) {
case V4L2_MPEG_VIDEO_VP8_PROFILE_0:
return C2Config::PROFILE_VP8_0;
case V4L2_MPEG_VIDEO_VP8_PROFILE_1:
return C2Config::PROFILE_VP8_1;
case V4L2_MPEG_VIDEO_VP8_PROFILE_2:
return C2Config::PROFILE_VP8_2;
case V4L2_MPEG_VIDEO_VP8_PROFILE_3:
return C2Config::PROFILE_VP8_3;
}
break;
case VideoCodec::VP9:
switch (profile) {
case V4L2_MPEG_VIDEO_VP9_PROFILE_0:
return C2Config::PROFILE_VP9_0;
case V4L2_MPEG_VIDEO_VP9_PROFILE_1:
return C2Config::PROFILE_VP9_1;
case V4L2_MPEG_VIDEO_VP9_PROFILE_2:
return C2Config::PROFILE_VP9_2;
case V4L2_MPEG_VIDEO_VP9_PROFILE_3:
return C2Config::PROFILE_VP9_3;
}
break;
default:
ALOGE("Unknown codec: %u", codec);
}
ALOGE("Unknown profile: %u", profile);
return C2Config::PROFILE_UNUSED;
}
std::vector<C2Config::profile_t> V4L2Device::v4L2PixFmtToC2Profiles(uint32_t pixFmt,
bool /*isEncoder*/) {
auto getSupportedProfiles = [this](VideoCodec codec,
std::vector<C2Config::profile_t>* profiles) {
uint32_t queryId = 0;
switch (codec) {
case VideoCodec::H264:
queryId = V4L2_CID_MPEG_VIDEO_H264_PROFILE;
break;
case VideoCodec::VP8:
queryId = V4L2_CID_MPEG_VIDEO_VP8_PROFILE;
break;
case VideoCodec::VP9:
queryId = V4L2_CID_MPEG_VIDEO_VP9_PROFILE;
break;
default:
return false;
}
v4l2_queryctrl queryCtrl = {};
queryCtrl.id = queryId;
if (ioctl(VIDIOC_QUERYCTRL, &queryCtrl) != 0) {
return false;
}
v4l2_querymenu queryMenu = {};
queryMenu.id = queryCtrl.id;
for (queryMenu.index = queryCtrl.minimum;
static_cast<int>(queryMenu.index) <= queryCtrl.maximum; queryMenu.index++) {
if (ioctl(VIDIOC_QUERYMENU, &queryMenu) == 0) {
const C2Config::profile_t profile =
V4L2Device::v4L2ProfileToC2Profile(codec, queryMenu.index);
if (profile != C2Config::PROFILE_UNUSED) profiles->push_back(profile);
}
}
return true;
};
std::vector<C2Config::profile_t> profiles;
switch (pixFmt) {
case V4L2_PIX_FMT_H264:
case V4L2_PIX_FMT_H264_SLICE:
if (!getSupportedProfiles(VideoCodec::H264, &profiles)) {
ALOGW("Driver doesn't support QUERY H264 profiles, "
"use default values, Base, Main, High");
profiles = {
C2Config::PROFILE_AVC_BASELINE,
C2Config::PROFILE_AVC_MAIN,
C2Config::PROFILE_AVC_HIGH,
};
}
break;
case V4L2_PIX_FMT_VP8:
case V4L2_PIX_FMT_VP8_FRAME:
if (!getSupportedProfiles(VideoCodec::VP8, &profiles)) {
ALOGW("Driver doesn't support QUERY VP8 profiles, use default values, Profile0");
profiles = {C2Config::PROFILE_VP8_0};
}
break;
case V4L2_PIX_FMT_VP9:
case V4L2_PIX_FMT_VP9_FRAME:
if (!getSupportedProfiles(VideoCodec::VP9, &profiles)) {
ALOGW("Driver doesn't support QUERY VP9 profiles, use default values, Profile0");
profiles = {C2Config::PROFILE_VP9_0};
}
break;
default:
ALOGE("Unhandled pixelformat %s", fourccToString(pixFmt).c_str());
return {};
}
// Erase duplicated profiles.
std::sort(profiles.begin(), profiles.end());
profiles.erase(std::unique(profiles.begin(), profiles.end()), profiles.end());
return profiles;
}
// static
int32_t V4L2Device::c2ProfileToV4L2H264Profile(C2Config::profile_t profile) {
switch (profile) {
case C2Config::PROFILE_AVC_BASELINE:
return V4L2_MPEG_VIDEO_H264_PROFILE_BASELINE;
case C2Config::PROFILE_AVC_MAIN:
return V4L2_MPEG_VIDEO_H264_PROFILE_MAIN;
case C2Config::PROFILE_AVC_EXTENDED:
return V4L2_MPEG_VIDEO_H264_PROFILE_EXTENDED;
case C2Config::PROFILE_AVC_HIGH:
return V4L2_MPEG_VIDEO_H264_PROFILE_HIGH;
case C2Config::PROFILE_AVC_HIGH_10:
return V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_10;
case C2Config::PROFILE_AVC_HIGH_422:
return V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_422;
case C2Config::PROFILE_AVC_HIGH_444_PREDICTIVE:
return V4L2_MPEG_VIDEO_H264_PROFILE_HIGH_444_PREDICTIVE;
case C2Config::PROFILE_AVC_SCALABLE_BASELINE:
return V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_BASELINE;
case C2Config::PROFILE_AVC_SCALABLE_HIGH:
return V4L2_MPEG_VIDEO_H264_PROFILE_SCALABLE_HIGH;
case C2Config::PROFILE_AVC_STEREO_HIGH:
return V4L2_MPEG_VIDEO_H264_PROFILE_STEREO_HIGH;
case C2Config::PROFILE_AVC_MULTIVIEW_HIGH:
return V4L2_MPEG_VIDEO_H264_PROFILE_MULTIVIEW_HIGH;
default:
ALOGE("Add more cases as needed");
return -1;
}
}
// static
int32_t V4L2Device::h264LevelIdcToV4L2H264Level(uint8_t levelIdc) {
switch (levelIdc) {
case 10:
return V4L2_MPEG_VIDEO_H264_LEVEL_1_0;
case 9:
return V4L2_MPEG_VIDEO_H264_LEVEL_1B;
case 11:
return V4L2_MPEG_VIDEO_H264_LEVEL_1_1;
case 12:
return V4L2_MPEG_VIDEO_H264_LEVEL_1_2;
case 13:
return V4L2_MPEG_VIDEO_H264_LEVEL_1_3;
case 20:
return V4L2_MPEG_VIDEO_H264_LEVEL_2_0;
case 21:
return V4L2_MPEG_VIDEO_H264_LEVEL_2_1;
case 22:
return V4L2_MPEG_VIDEO_H264_LEVEL_2_2;
case 30:
return V4L2_MPEG_VIDEO_H264_LEVEL_3_0;
case 31:
return V4L2_MPEG_VIDEO_H264_LEVEL_3_1;
case 32:
return V4L2_MPEG_VIDEO_H264_LEVEL_3_2;
case 40:
return V4L2_MPEG_VIDEO_H264_LEVEL_4_0;
case 41:
return V4L2_MPEG_VIDEO_H264_LEVEL_4_1;
case 42:
return V4L2_MPEG_VIDEO_H264_LEVEL_4_2;
case 50:
return V4L2_MPEG_VIDEO_H264_LEVEL_5_0;
case 51:
return V4L2_MPEG_VIDEO_H264_LEVEL_5_1;
default:
ALOGE("Unrecognized levelIdc: %u", static_cast<uint32_t>(levelIdc));
return -1;
}
}
// static
ui::Size V4L2Device::allocatedSizeFromV4L2Format(const struct v4l2_format& format) {
ui::Size codedSize;
ui::Size visibleSize;
VideoPixelFormat frameFormat = VideoPixelFormat::UNKNOWN;
size_t bytesPerLine = 0;
// Total bytes in the frame.
size_t sizeimage = 0;
if (V4L2_TYPE_IS_MULTIPLANAR(format.type)) {
ALOG_ASSERT(format.fmt.pix_mp.num_planes > 0);
bytesPerLine = base::checked_cast<int>(format.fmt.pix_mp.plane_fmt[0].bytesperline);
for (size_t i = 0; i < format.fmt.pix_mp.num_planes; ++i) {
sizeimage += base::checked_cast<int>(format.fmt.pix_mp.plane_fmt[i].sizeimage);
}
visibleSize.set(base::checked_cast<int>(format.fmt.pix_mp.width),
base::checked_cast<int>(format.fmt.pix_mp.height));
const uint32_t pixFmt = format.fmt.pix_mp.pixelformat;
const auto frameFourcc = Fourcc::fromV4L2PixFmt(pixFmt);
if (!frameFourcc) {
ALOGE("Unsupported format %s", fourccToString(pixFmt).c_str());
return codedSize;
}
frameFormat = frameFourcc->toVideoPixelFormat();
} else {
bytesPerLine = base::checked_cast<int>(format.fmt.pix.bytesperline);
sizeimage = base::checked_cast<int>(format.fmt.pix.sizeimage);
visibleSize.set(base::checked_cast<int>(format.fmt.pix.width),
base::checked_cast<int>(format.fmt.pix.height));
const uint32_t fourcc = format.fmt.pix.pixelformat;
const auto frameFourcc = Fourcc::fromV4L2PixFmt(fourcc);
if (!frameFourcc) {
ALOGE("Unsupported format %s", fourccToString(fourcc).c_str());
return codedSize;
}
frameFormat = frameFourcc ? frameFourcc->toVideoPixelFormat() : VideoPixelFormat::UNKNOWN;
}
// V4L2 does not provide per-plane bytesperline (bpl) when different components are sharing one
// physical plane buffer. In this case, it only provides bpl for the first component in the
// plane. So we can't depend on it for calculating height, because bpl may vary within one
// physical plane buffer. For example, YUV420 contains 3 components in one physical plane, with
// Y at 8 bits per pixel, and Cb/Cr at 4 bits per pixel per component, but we only get 8 pits
// per pixel from bytesperline in physical plane 0. So we need to get total frame bpp from
// elsewhere to calculate coded height.
// We need bits per pixel for one component only to calculate the coded width from bytesperline.
int planeHorizBitsPerPixel = planeHorizontalBitsPerPixel(frameFormat, 0);
// Adding up bpp for each component will give us total bpp for all components.
int totalBpp = 0;
for (size_t i = 0; i < numPlanes(frameFormat); ++i)
totalBpp += planeBitsPerPixel(frameFormat, i);
if (sizeimage == 0 || bytesPerLine == 0 || planeHorizBitsPerPixel == 0 || totalBpp == 0 ||
(bytesPerLine * 8) % planeHorizBitsPerPixel != 0) {
ALOGE("Invalid format provided");
return codedSize;
}
// Coded width can be calculated by taking the first component's bytesperline, which in V4L2
// always applies to the first component in physical plane buffer.
int codedWidth = bytesPerLine * 8 / planeHorizBitsPerPixel;
// Sizeimage is codedWidth * codedHeight * totalBpp.
int codedHeight = sizeimage * 8 / codedWidth / totalBpp;
codedSize.set(codedWidth, codedHeight);
ALOGV("codedSize=%s", toString(codedSize).c_str());
// Sanity checks. Calculated coded size has to contain given visible size and fulfill buffer
// byte size requirements.
ALOG_ASSERT(Rect(codedSize).Contains(Rect(visibleSize)));
ALOG_ASSERT(sizeimage <= allocationSize(frameFormat, codedSize));
return codedSize;
}
// static
const char* V4L2Device::v4L2MemoryToString(const v4l2_memory memory) {
switch (memory) {
case V4L2_MEMORY_MMAP:
return "V4L2_MEMORY_MMAP";
case V4L2_MEMORY_USERPTR:
return "V4L2_MEMORY_USERPTR";
case V4L2_MEMORY_DMABUF:
return "V4L2_MEMORY_DMABUF";
case V4L2_MEMORY_OVERLAY:
return "V4L2_MEMORY_OVERLAY";
default:
return "UNKNOWN";
}
}
// static
const char* V4L2Device::v4L2BufferTypeToString(const enum v4l2_buf_type bufType) {
switch (bufType) {
case V4L2_BUF_TYPE_VIDEO_OUTPUT:
return "OUTPUT";
case V4L2_BUF_TYPE_VIDEO_CAPTURE:
return "CAPTURE";
case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
return "OUTPUT_MPLANE";
case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
return "CAPTURE_MPLANE";
default:
return "UNKNOWN";
}
}
// static
std::string V4L2Device::v4L2FormatToString(const struct v4l2_format& format) {
std::ostringstream s;
s << "v4l2_format type: " << format.type;
if (format.type == V4L2_BUF_TYPE_VIDEO_CAPTURE || format.type == V4L2_BUF_TYPE_VIDEO_OUTPUT) {
// single-planar
const struct v4l2_pix_format& pix = format.fmt.pix;
s << ", width_height: " << toString(ui::Size(pix.width, pix.height))
<< ", pixelformat: " << fourccToString(pix.pixelformat) << ", field: " << pix.field
<< ", bytesperline: " << pix.bytesperline << ", sizeimage: " << pix.sizeimage;
} else if (V4L2_TYPE_IS_MULTIPLANAR(format.type)) {
const struct v4l2_pix_format_mplane& pixMp = format.fmt.pix_mp;
// As long as num_planes's type is uint8_t, ostringstream treats it as a char instead of an
// integer, which is not what we want. Casting pix_mp.num_planes unsigned int solves the
// issue.
s << ", width_height: " << toString(ui::Size(pixMp.width, pixMp.height))
<< ", pixelformat: " << fourccToString(pixMp.pixelformat) << ", field: " << pixMp.field
<< ", num_planes: " << static_cast<unsigned int>(pixMp.num_planes);
for (size_t i = 0; i < pixMp.num_planes; ++i) {
const struct v4l2_plane_pix_format& plane_fmt = pixMp.plane_fmt[i];
s << ", plane_fmt[" << i << "].sizeimage: " << plane_fmt.sizeimage << ", plane_fmt["
<< i << "].bytesperline: " << plane_fmt.bytesperline;
}
} else {
s << " unsupported yet.";
}
return s.str();
}
// static
std::string V4L2Device::v4L2BufferToString(const struct v4l2_buffer& buffer) {
std::ostringstream s;
s << "v4l2_buffer type: " << buffer.type << ", memory: " << buffer.memory
<< ", index: " << buffer.index << " bytesused: " << buffer.bytesused
<< ", length: " << buffer.length;
if (buffer.type == V4L2_BUF_TYPE_VIDEO_CAPTURE || buffer.type == V4L2_BUF_TYPE_VIDEO_OUTPUT) {
// single-planar
if (buffer.memory == V4L2_MEMORY_MMAP) {
s << ", m.offset: " << buffer.m.offset;
} else if (buffer.memory == V4L2_MEMORY_USERPTR) {
s << ", m.userptr: " << buffer.m.userptr;
} else if (buffer.memory == V4L2_MEMORY_DMABUF) {
s << ", m.fd: " << buffer.m.fd;
};
} else if (V4L2_TYPE_IS_MULTIPLANAR(buffer.type)) {
for (size_t i = 0; i < buffer.length; ++i) {
const struct v4l2_plane& plane = buffer.m.planes[i];
s << ", m.planes[" << i << "](bytesused: " << plane.bytesused
<< ", length: " << plane.length << ", data_offset: " << plane.data_offset;
if (buffer.memory == V4L2_MEMORY_MMAP) {
s << ", m.mem_offset: " << plane.m.mem_offset;
} else if (buffer.memory == V4L2_MEMORY_USERPTR) {
s << ", m.userptr: " << plane.m.userptr;
} else if (buffer.memory == V4L2_MEMORY_DMABUF) {
s << ", m.fd: " << plane.m.fd;
}
s << ")";
}
} else {
s << " unsupported yet.";
}
return s.str();
}
// static
std::optional<VideoFrameLayout> V4L2Device::v4L2FormatToVideoFrameLayout(
const struct v4l2_format& format) {
if (!V4L2_TYPE_IS_MULTIPLANAR(format.type)) {
ALOGE("v4l2_buf_type is not multiplanar: 0x%" PRIx32, format.type);
return std::nullopt;
}
const v4l2_pix_format_mplane& pixMp = format.fmt.pix_mp;
const uint32_t& pixFmt = pixMp.pixelformat;
const auto videoFourcc = Fourcc::fromV4L2PixFmt(pixFmt);
if (!videoFourcc) {
ALOGE("Failed to convert pixel format to VideoPixelFormat: %s",
fourccToString(pixFmt).c_str());
return std::nullopt;
}
const VideoPixelFormat videoFormat = videoFourcc->toVideoPixelFormat();
const size_t numBuffers = pixMp.num_planes;
const size_t numColorPlanes = numPlanes(videoFormat);
if (numColorPlanes == 0) {
ALOGE("Unsupported video format for NumPlanes(): %s",
videoPixelFormatToString(videoFormat).c_str());
return std::nullopt;
}
if (numBuffers > numColorPlanes) {
ALOGE("pix_mp.num_planes: %zu should not be larger than NumPlanes(%s): %zu", numBuffers,
videoPixelFormatToString(videoFormat).c_str(), numColorPlanes);
return std::nullopt;
}
// Reserve capacity in advance to prevent unnecessary vector reallocation.
std::vector<VideoFramePlane> planes;
planes.reserve(numColorPlanes);
for (size_t i = 0; i < numBuffers; ++i) {
const v4l2_plane_pix_format& planeFormat = pixMp.plane_fmt[i];
planes.push_back(VideoFramePlane{planeFormat.bytesperline, 0u, planeFormat.sizeimage});
}
// For the case that #color planes > #buffers, it fills stride of color plane which does not map
// to buffer. Right now only some pixel formats are supported: NV12, YUV420, YVU420.
if (numColorPlanes > numBuffers) {
const uint32_t yStride = planes[0].mStride;
// Note that y_stride is from v4l2 bytesperline and its type is uint32_t. It is safe to cast
// to size_t.
const size_t yStrideAbs = static_cast<size_t>(yStride);
switch (pixFmt) {
case V4L2_PIX_FMT_NV12:
// The stride of UV is the same as Y in NV12. The height is half of Y plane.
planes.push_back(VideoFramePlane{yStride, yStrideAbs * pixMp.height,
yStrideAbs * pixMp.height / 2});
ALOG_ASSERT(2u == planes.size());
break;
case V4L2_PIX_FMT_YUV420:
case V4L2_PIX_FMT_YVU420: {
// The spec claims that two Cx rows (including padding) is exactly as long as one Y row
// (including padding). So stride of Y must be even number.
if (yStride % 2 != 0 || pixMp.height % 2 != 0) {
ALOGE("Plane-Y stride and height should be even; stride: %u, height: %u", yStride,
pixMp.height);
return std::nullopt;
}
const uint32_t halfStride = yStride / 2;
const size_t plane0Area = yStrideAbs * pixMp.height;
const size_t plane1Area = plane0Area / 4;
planes.push_back(VideoFramePlane{halfStride, plane0Area, plane1Area});
planes.push_back(VideoFramePlane{halfStride, plane0Area + plane1Area, plane1Area});
ALOG_ASSERT(3u == planes.size());
break;
}
default:
ALOGE("Cannot derive stride for each plane for pixel format %s",
fourccToString(pixFmt).c_str());
return std::nullopt;
}
}
return VideoFrameLayout{videoFormat, ui::Size(pixMp.width, pixMp.height), std::move(planes),
(numBuffers > 1)};
}
// static
size_t V4L2Device::getNumPlanesOfV4L2PixFmt(uint32_t pixFmt) {
std::optional<Fourcc> fourcc = Fourcc::fromV4L2PixFmt(pixFmt);
if (fourcc && fourcc->isMultiPlanar()) {
return numPlanes(fourcc->toVideoPixelFormat());
}
return 1u;
}
void V4L2Device::getSupportedResolution(uint32_t pixelFormat, ui::Size* minResolution,
ui::Size* maxResolution) {
maxResolution->set(0, 0);
minResolution->set(0, 0);
v4l2_frmsizeenum frameSize;
memset(&frameSize, 0, sizeof(frameSize));
frameSize.pixel_format = pixelFormat;
for (; ioctl(VIDIOC_ENUM_FRAMESIZES, &frameSize) == 0; ++frameSize.index) {
if (frameSize.type == V4L2_FRMSIZE_TYPE_DISCRETE) {
if (frameSize.discrete.width >= base::checked_cast<uint32_t>(maxResolution->width) &&
frameSize.discrete.height >= base::checked_cast<uint32_t>(maxResolution->height)) {
maxResolution->set(frameSize.discrete.width, frameSize.discrete.height);
}
if (isEmpty(*minResolution) ||
(frameSize.discrete.width <= base::checked_cast<uint32_t>(minResolution->width) &&
frameSize.discrete.height <=
base::checked_cast<uint32_t>(minResolution->height))) {
minResolution->set(frameSize.discrete.width, frameSize.discrete.height);
}
} else if (frameSize.type == V4L2_FRMSIZE_TYPE_STEPWISE ||
frameSize.type == V4L2_FRMSIZE_TYPE_CONTINUOUS) {
maxResolution->set(frameSize.stepwise.max_width, frameSize.stepwise.max_height);
minResolution->set(frameSize.stepwise.min_width, frameSize.stepwise.min_height);
break;
}
}
if (isEmpty(*maxResolution)) {
maxResolution->set(1920, 1088);
ALOGE("GetSupportedResolution failed to get maximum resolution for fourcc %s, "
"fall back to %s",
fourccToString(pixelFormat).c_str(), toString(*maxResolution).c_str());
}
if (isEmpty(*minResolution)) {
minResolution->set(16, 16);
ALOGE("GetSupportedResolution failed to get minimum resolution for fourcc %s, "
"fall back to %s",
fourccToString(pixelFormat).c_str(), toString(*minResolution).c_str());
}
}
std::vector<uint32_t> V4L2Device::enumerateSupportedPixelformats(v4l2_buf_type bufType) {
std::vector<uint32_t> pixelFormats;
v4l2_fmtdesc fmtDesc;
memset(&fmtDesc, 0, sizeof(fmtDesc));
fmtDesc.type = bufType;
for (; ioctl(VIDIOC_ENUM_FMT, &fmtDesc) == 0; ++fmtDesc.index) {
ALOGV("Found %s (0x%" PRIx32 ")", fmtDesc.description, fmtDesc.pixelformat);
pixelFormats.push_back(fmtDesc.pixelformat);
}
return pixelFormats;
}
V4L2Device::SupportedDecodeProfiles V4L2Device::getSupportedDecodeProfiles(
const size_t numFormats, const uint32_t pixelFormats[]) {
SupportedDecodeProfiles supportedProfiles;
Type type = Type::kDecoder;
const auto& devices = getDevicesForType(type);
for (const auto& device : devices) {
if (!openDevicePath(device.first, type)) {
ALOGV("Failed opening %s", device.first.c_str());
continue;
}
const auto& profiles = enumerateSupportedDecodeProfiles(numFormats, pixelFormats);
supportedProfiles.insert(supportedProfiles.end(), profiles.begin(), profiles.end());
closeDevice();
}
return supportedProfiles;
}
V4L2Device::SupportedEncodeProfiles V4L2Device::getSupportedEncodeProfiles() {
SupportedEncodeProfiles supportedProfiles;
Type type = Type::kEncoder;
const auto& devices = getDevicesForType(type);
for (const auto& device : devices) {
if (!openDevicePath(device.first, type)) {
ALOGV("Failed opening %s", device.first.c_str());
continue;
}
const auto& profiles = enumerateSupportedEncodeProfiles();
supportedProfiles.insert(supportedProfiles.end(), profiles.begin(), profiles.end());
closeDevice();
}
return supportedProfiles;
}
V4L2Device::SupportedDecodeProfiles V4L2Device::enumerateSupportedDecodeProfiles(
const size_t numFormats, const uint32_t pixelFormats[]) {
SupportedDecodeProfiles profiles;
const auto& supportedPixelformats =
enumerateSupportedPixelformats(V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE);
for (uint32_t pixelFormat : supportedPixelformats) {
if (std::find(pixelFormats, pixelFormats + numFormats, pixelFormat) ==
pixelFormats + numFormats)
continue;
SupportedDecodeProfile profile;
getSupportedResolution(pixelFormat, &profile.min_resolution, &profile.max_resolution);
const auto videoCodecProfiles = v4L2PixFmtToC2Profiles(pixelFormat, false);
for (const auto& videoCodecProfile : videoCodecProfiles) {
profile.profile = videoCodecProfile;
profiles.push_back(profile);
ALOGV("Found decoder profile %s, resolutions: %s %s", profileToString(profile.profile),
toString(profile.min_resolution).c_str(),
toString(profile.max_resolution).c_str());
}
}
return profiles;
}
V4L2Device::SupportedEncodeProfiles V4L2Device::enumerateSupportedEncodeProfiles() {
SupportedEncodeProfiles profiles;
const auto& supportedPixelformats =
enumerateSupportedPixelformats(V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE);
for (const auto& pixelformat : supportedPixelformats) {
SupportedEncodeProfile profile;
profile.max_framerate_numerator = 30;
profile.max_framerate_denominator = 1;
ui::Size minResolution;
getSupportedResolution(pixelformat, &minResolution, &profile.max_resolution);
const auto videoCodecProfiles = v4L2PixFmtToC2Profiles(pixelformat, true);
for (const auto& videoCodecProfile : videoCodecProfiles) {
profile.profile = videoCodecProfile;
profiles.push_back(profile);
ALOGV("Found encoder profile %s, max resolution: %s", profileToString(profile.profile),
toString(profile.max_resolution).c_str());
}
}
return profiles;
}
bool V4L2Device::startPolling(android::V4L2DevicePoller::EventCallback eventCallback,
base::RepeatingClosure errorCallback) {
DCHECK_CALLED_ON_VALID_SEQUENCE(mClientSequenceChecker);
if (!mDevicePoller) {
mDevicePoller = std::make_unique<android::V4L2DevicePoller>(this, "V4L2DeviceThreadPoller");
}
bool ret = mDevicePoller->startPolling(std::move(eventCallback), std::move(errorCallback));
if (!ret) mDevicePoller = nullptr;
return ret;
}
bool V4L2Device::stopPolling() {
DCHECK_CALLED_ON_VALID_SEQUENCE(mClientSequenceChecker);
return !mDevicePoller || mDevicePoller->stopPolling();
}
void V4L2Device::schedulePoll() {
DCHECK_CALLED_ON_VALID_SEQUENCE(mClientSequenceChecker);
if (!mDevicePoller || !mDevicePoller->isPolling()) return;
mDevicePoller->schedulePoll();
}
bool V4L2Device::isCtrlExposed(uint32_t ctrlId) {
DCHECK_CALLED_ON_VALID_SEQUENCE(mClientSequenceChecker);
struct v4l2_queryctrl queryCtrl;
memset(&queryCtrl, 0, sizeof(queryCtrl));
queryCtrl.id = ctrlId;
return ioctl(VIDIOC_QUERYCTRL, &queryCtrl) == 0;
}
bool V4L2Device::setExtCtrls(uint32_t ctrlClass, std::vector<V4L2ExtCtrl> ctrls) {
DCHECK_CALLED_ON_VALID_SEQUENCE(mClientSequenceChecker);
if (ctrls.empty()) return true;
struct v4l2_ext_controls extCtrls;
memset(&extCtrls, 0, sizeof(extCtrls));
extCtrls.ctrl_class = ctrlClass;
extCtrls.count = ctrls.size();
extCtrls.controls = &ctrls[0].ctrl;
return ioctl(VIDIOC_S_EXT_CTRLS, &extCtrls) == 0;
}
bool V4L2Device::isCommandSupported(uint32_t commandId) {
DCHECK_CALLED_ON_VALID_SEQUENCE(mClientSequenceChecker);
struct v4l2_encoder_cmd cmd;
memset(&cmd, 0, sizeof(cmd));
cmd.cmd = commandId;
return ioctl(VIDIOC_TRY_ENCODER_CMD, &cmd) == 0;
}
bool V4L2Device::hasCapabilities(uint32_t capabilities) {
DCHECK_CALLED_ON_VALID_SEQUENCE(mClientSequenceChecker);
struct v4l2_capability caps;
memset(&caps, 0, sizeof(caps));
if (ioctl(VIDIOC_QUERYCAP, &caps) != 0) {
ALOGE("Failed to query capabilities");
return false;
}
return (caps.capabilities & capabilities) == capabilities;
}
bool V4L2Device::openDevicePath(const std::string& path, Type /*type*/) {
ALOG_ASSERT(!mDeviceFd.is_valid());
mDeviceFd.reset(HANDLE_EINTR(::open(path.c_str(), O_RDWR | O_NONBLOCK | O_CLOEXEC)));
if (!mDeviceFd.is_valid()) return false;
return true;
}
void V4L2Device::closeDevice() {
ALOGV("%s()", __func__);
mDeviceFd.reset();
}
void V4L2Device::enumerateDevicesForType(Type type) {
// video input/output devices are registered as /dev/videoX in V4L2.
static const std::string kVideoDevicePattern = "/dev/video";
std::string devicePattern;
v4l2_buf_type bufType;
switch (type) {
case Type::kDecoder:
devicePattern = kVideoDevicePattern;
bufType = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
break;
case Type::kEncoder:
devicePattern = kVideoDevicePattern;
bufType = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
break;
default:
ALOGE("Only decoder and encoder types are supported!!");
return;
}
std::vector<std::string> candidatePaths;
// TODO(posciak): Remove this legacy unnumbered device once all platforms are updated to use
// numbered devices.
candidatePaths.push_back(devicePattern);
// We are sandboxed, so we can't query directory contents to check which devices are actually
// available. Try to open the first 10; if not present, we will just fail to open immediately.
for (int i = 0; i < 10; ++i) {
candidatePaths.push_back(base::StringPrintf("%s%d", devicePattern.c_str(), i));
}
Devices devices;
for (const auto& path : candidatePaths) {
if (!openDevicePath(path, type)) {
continue;
}
const auto& supportedPixelformats = enumerateSupportedPixelformats(bufType);
if (!supportedPixelformats.empty()) {
ALOGV("Found device: %s", path.c_str());
devices.push_back(std::make_pair(path, supportedPixelformats));
}
closeDevice();
}
ALOG_ASSERT(mDevicesByType.count(type) == 0u);
mDevicesByType[type] = devices;
}
const V4L2Device::Devices& V4L2Device::getDevicesForType(Type type) {
if (mDevicesByType.count(type) == 0) enumerateDevicesForType(type);
ALOG_ASSERT(mDevicesByType.count(type) != 0u);
return mDevicesByType[type];
}
std::string V4L2Device::getDevicePathFor(Type type, uint32_t pixFmt) {
const Devices& devices = getDevicesForType(type);
for (const auto& device : devices) {
if (std::find(device.second.begin(), device.second.end(), pixFmt) != device.second.end())
return device.first;
}
return std::string();
}
} // namespace android