1 // Copyright 2014 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include <errno.h>
6 #include <fcntl.h>
7 #include <poll.h>
8 #include <string.h>
9 #include <sys/eventfd.h>
10 #include <sys/ioctl.h>
11 #include <sys/mman.h>
12
13 #include "base/numerics/safe_conversions.h"
14 #include "base/posix/eintr_wrapper.h"
15 #include "base/strings/stringprintf.h"
16 #include "v4l2_device.h"
17
18 namespace media {
19
V4L2Device()20 V4L2Device::V4L2Device() {}
21
~V4L2Device()22 V4L2Device::~V4L2Device() {
23 CloseDevice();
24 }
25
26 // static
V4L2PixFmtToVideoPixelFormat(uint32_t pix_fmt)27 VideoPixelFormat V4L2Device::V4L2PixFmtToVideoPixelFormat(uint32_t pix_fmt) {
28 switch (pix_fmt) {
29 case V4L2_PIX_FMT_NV12:
30 case V4L2_PIX_FMT_NV12M:
31 return PIXEL_FORMAT_NV12;
32
33 case V4L2_PIX_FMT_MT21:
34 return PIXEL_FORMAT_MT21;
35
36 case V4L2_PIX_FMT_YUV420:
37 case V4L2_PIX_FMT_YUV420M:
38 return PIXEL_FORMAT_I420;
39
40 case V4L2_PIX_FMT_YVU420:
41 return PIXEL_FORMAT_YV12;
42
43 case V4L2_PIX_FMT_YUV422M:
44 return PIXEL_FORMAT_I422;
45
46 case V4L2_PIX_FMT_RGB32:
47 return PIXEL_FORMAT_ARGB;
48
49 default:
50 DVLOG(1) << "Add more cases as needed";
51 return PIXEL_FORMAT_UNKNOWN;
52 }
53 }
54
55 // static
VideoPixelFormatToV4L2PixFmt(VideoPixelFormat format)56 uint32_t V4L2Device::VideoPixelFormatToV4L2PixFmt(VideoPixelFormat format) {
57 switch (format) {
58 case PIXEL_FORMAT_NV12:
59 return V4L2_PIX_FMT_NV12M;
60
61 case PIXEL_FORMAT_MT21:
62 return V4L2_PIX_FMT_MT21;
63
64 case PIXEL_FORMAT_I420:
65 return V4L2_PIX_FMT_YUV420M;
66
67 case PIXEL_FORMAT_YV12:
68 return V4L2_PIX_FMT_YVU420;
69
70 default:
71 LOG(FATAL) << "Add more cases as needed";
72 return 0;
73 }
74 }
75
76 // static
VideoCodecProfileToV4L2PixFmt(VideoCodecProfile profile,bool slice_based)77 uint32_t V4L2Device::VideoCodecProfileToV4L2PixFmt(VideoCodecProfile profile,
78 bool slice_based) {
79 if (profile >= H264PROFILE_MIN && profile <= H264PROFILE_MAX) {
80 if (slice_based)
81 return V4L2_PIX_FMT_H264_SLICE;
82 else
83 return V4L2_PIX_FMT_H264;
84 } else if (profile >= VP8PROFILE_MIN && profile <= VP8PROFILE_MAX) {
85 if (slice_based)
86 return V4L2_PIX_FMT_VP8_FRAME;
87 else
88 return V4L2_PIX_FMT_VP8;
89 } else if (profile >= VP9PROFILE_MIN && profile <= VP9PROFILE_MAX) {
90 if (slice_based)
91 return V4L2_PIX_FMT_VP9_FRAME;
92 else
93 return V4L2_PIX_FMT_VP9;
94 } else {
95 LOG(FATAL) << "Add more cases as needed";
96 return 0;
97 }
98 }
99
100 // static
V4L2PixFmtToVideoCodecProfiles(uint32_t pix_fmt,bool is_encoder)101 std::vector<VideoCodecProfile> V4L2Device::V4L2PixFmtToVideoCodecProfiles(
102 uint32_t pix_fmt,
103 bool is_encoder) {
104 VideoCodecProfile min_profile, max_profile;
105 std::vector<VideoCodecProfile> profiles;
106
107 switch (pix_fmt) {
108 case V4L2_PIX_FMT_H264:
109 case V4L2_PIX_FMT_H264_SLICE:
110 if (is_encoder) {
111 // TODO(posciak): need to query the device for supported H.264 profiles,
112 // for now choose Main as a sensible default.
113 min_profile = H264PROFILE_MAIN;
114 max_profile = H264PROFILE_MAIN;
115 } else {
116 min_profile = H264PROFILE_MIN;
117 max_profile = H264PROFILE_MAX;
118 }
119 break;
120
121 case V4L2_PIX_FMT_VP8:
122 case V4L2_PIX_FMT_VP8_FRAME:
123 min_profile = VP8PROFILE_MIN;
124 max_profile = VP8PROFILE_MAX;
125 break;
126
127 case V4L2_PIX_FMT_VP9:
128 case V4L2_PIX_FMT_VP9_FRAME:
129 min_profile = VP9PROFILE_MIN;
130 max_profile = VP9PROFILE_MAX;
131 break;
132
133 default:
134 DVLOG(1) << "Unhandled pixelformat " << std::hex << "0x" << pix_fmt;
135 return profiles;
136 }
137
138 for (int profile = min_profile; profile <= max_profile; ++profile)
139 profiles.push_back(static_cast<VideoCodecProfile>(profile));
140
141 return profiles;
142 }
143
Ioctl(int request,void * arg)144 int V4L2Device::Ioctl(int request, void* arg) {
145 DCHECK(device_fd_.is_valid());
146 return HANDLE_EINTR(ioctl(device_fd_.get(), request, arg));
147 }
148
Poll(bool poll_device,bool * event_pending)149 bool V4L2Device::Poll(bool poll_device, bool* event_pending) {
150 struct pollfd pollfds[2];
151 nfds_t nfds;
152 int pollfd = -1;
153
154 pollfds[0].fd = device_poll_interrupt_fd_.get();
155 pollfds[0].events = POLLIN | POLLERR;
156 nfds = 1;
157
158 if (poll_device) {
159 DVLOG(3) << "Poll(): adding device fd to poll() set";
160 pollfds[nfds].fd = device_fd_.get();
161 pollfds[nfds].events = POLLIN | POLLOUT | POLLERR | POLLPRI;
162 pollfd = nfds;
163 nfds++;
164 }
165
166 if (HANDLE_EINTR(poll(pollfds, nfds, -1)) == -1) {
167 DPLOG(ERROR) << "poll() failed";
168 return false;
169 }
170 *event_pending = (pollfd != -1 && pollfds[pollfd].revents & POLLPRI);
171 return true;
172 }
173
Mmap(void * addr,unsigned int len,int prot,int flags,unsigned int offset)174 void* V4L2Device::Mmap(void* addr,
175 unsigned int len,
176 int prot,
177 int flags,
178 unsigned int offset) {
179 DCHECK(device_fd_.is_valid());
180 return mmap(addr, len, prot, flags, device_fd_.get(), offset);
181 }
182
Munmap(void * addr,unsigned int len)183 void V4L2Device::Munmap(void* addr, unsigned int len) {
184 munmap(addr, len);
185 }
186
SetDevicePollInterrupt()187 bool V4L2Device::SetDevicePollInterrupt() {
188 DVLOG(3) << "SetDevicePollInterrupt()";
189
190 const uint64_t buf = 1;
191 if (HANDLE_EINTR(write(device_poll_interrupt_fd_.get(), &buf, sizeof(buf))) ==
192 -1) {
193 DPLOG(ERROR) << "SetDevicePollInterrupt(): write() failed";
194 return false;
195 }
196 return true;
197 }
198
ClearDevicePollInterrupt()199 bool V4L2Device::ClearDevicePollInterrupt() {
200 DVLOG(3) << "ClearDevicePollInterrupt()";
201
202 uint64_t buf;
203 if (HANDLE_EINTR(read(device_poll_interrupt_fd_.get(), &buf, sizeof(buf))) ==
204 -1) {
205 if (errno == EAGAIN) {
206 // No interrupt flag set, and we're reading nonblocking. Not an error.
207 return true;
208 } else {
209 DPLOG(ERROR) << "ClearDevicePollInterrupt(): read() failed";
210 return false;
211 }
212 }
213 return true;
214 }
215
Open(Type type,uint32_t v4l2_pixfmt)216 bool V4L2Device::Open(Type type, uint32_t v4l2_pixfmt) {
217 std::string path = GetDevicePathFor(type, v4l2_pixfmt);
218
219 if (path.empty()) {
220 DVLOG(1) << "No devices supporting " << std::hex << "0x" << v4l2_pixfmt
221 << " for type: " << static_cast<int>(type);
222 return false;
223 }
224
225 if (!OpenDevicePath(path, type)) {
226 LOG(ERROR) << "Failed opening " << path;
227 return false;
228 }
229
230 device_poll_interrupt_fd_.reset(eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC));
231 if (!device_poll_interrupt_fd_.is_valid()) {
232 LOG(ERROR) << "Failed creating a poll interrupt fd";
233 return false;
234 }
235
236 return true;
237 }
238
GetDmabufsForV4L2Buffer(int index,size_t num_planes,enum v4l2_buf_type buf_type)239 std::vector<base::ScopedFD> V4L2Device::GetDmabufsForV4L2Buffer(
240 int index,
241 size_t num_planes,
242 enum v4l2_buf_type buf_type) {
243 DCHECK(V4L2_TYPE_IS_MULTIPLANAR(buf_type));
244
245 std::vector<base::ScopedFD> dmabuf_fds;
246 for (size_t i = 0; i < num_planes; ++i) {
247 struct v4l2_exportbuffer expbuf;
248 memset(&expbuf, 0, sizeof(expbuf));
249 expbuf.type = buf_type;
250 expbuf.index = index;
251 expbuf.plane = i;
252 expbuf.flags = O_CLOEXEC;
253 if (Ioctl(VIDIOC_EXPBUF, &expbuf) != 0) {
254 dmabuf_fds.clear();
255 break;
256 }
257
258 dmabuf_fds.push_back(base::ScopedFD(expbuf.fd));
259 }
260
261 return dmabuf_fds;
262 }
263
264 VideoDecodeAccelerator::SupportedProfiles
GetSupportedDecodeProfiles(const size_t num_formats,const uint32_t pixelformats[])265 V4L2Device::GetSupportedDecodeProfiles(const size_t num_formats,
266 const uint32_t pixelformats[]) {
267 VideoDecodeAccelerator::SupportedProfiles supported_profiles;
268
269 Type type = Type::kDecoder;
270 const auto& devices = GetDevicesForType(type);
271 for (const auto& device : devices) {
272 if (!OpenDevicePath(device.first, type)) {
273 LOG(ERROR) << "Failed opening " << device.first;
274 continue;
275 }
276
277 const auto& profiles =
278 EnumerateSupportedDecodeProfiles(num_formats, pixelformats);
279 supported_profiles.insert(supported_profiles.end(), profiles.begin(),
280 profiles.end());
281 CloseDevice();
282 }
283
284 return supported_profiles;
285 }
286
GetSupportedResolution(uint32_t pixelformat,Size * min_resolution,Size * max_resolution)287 void V4L2Device::GetSupportedResolution(uint32_t pixelformat,
288 Size* min_resolution,
289 Size* max_resolution) {
290 max_resolution->SetSize(0, 0);
291 min_resolution->SetSize(0, 0);
292 v4l2_frmsizeenum frame_size;
293 memset(&frame_size, 0, sizeof(frame_size));
294 frame_size.pixel_format = pixelformat;
295 for (; Ioctl(VIDIOC_ENUM_FRAMESIZES, &frame_size) == 0; ++frame_size.index) {
296 if (frame_size.type == V4L2_FRMSIZE_TYPE_DISCRETE) {
297 if (frame_size.discrete.width >=
298 base::checked_cast<uint32_t>(max_resolution->width()) &&
299 frame_size.discrete.height >=
300 base::checked_cast<uint32_t>(max_resolution->height())) {
301 max_resolution->SetSize(frame_size.discrete.width,
302 frame_size.discrete.height);
303 }
304 if (min_resolution->IsEmpty() ||
305 (frame_size.discrete.width <=
306 base::checked_cast<uint32_t>(min_resolution->width()) &&
307 frame_size.discrete.height <=
308 base::checked_cast<uint32_t>(min_resolution->height()))) {
309 min_resolution->SetSize(frame_size.discrete.width,
310 frame_size.discrete.height);
311 }
312 } else if (frame_size.type == V4L2_FRMSIZE_TYPE_STEPWISE ||
313 frame_size.type == V4L2_FRMSIZE_TYPE_CONTINUOUS) {
314 max_resolution->SetSize(frame_size.stepwise.max_width,
315 frame_size.stepwise.max_height);
316 min_resolution->SetSize(frame_size.stepwise.min_width,
317 frame_size.stepwise.min_height);
318 break;
319 }
320 }
321 if (max_resolution->IsEmpty()) {
322 max_resolution->SetSize(1920, 1088);
323 LOG(ERROR) << "GetSupportedResolution failed to get maximum resolution for "
324 << "fourcc " << std::hex << pixelformat
325 << ", fall back to " << max_resolution->ToString();
326 }
327 if (min_resolution->IsEmpty()) {
328 min_resolution->SetSize(16, 16);
329 LOG(ERROR) << "GetSupportedResolution failed to get minimum resolution for "
330 << "fourcc " << std::hex << pixelformat
331 << ", fall back to " << min_resolution->ToString();
332 }
333 }
334
EnumerateSupportedPixelformats(v4l2_buf_type buf_type)335 std::vector<uint32_t> V4L2Device::EnumerateSupportedPixelformats(
336 v4l2_buf_type buf_type) {
337 std::vector<uint32_t> pixelformats;
338
339 v4l2_fmtdesc fmtdesc;
340 memset(&fmtdesc, 0, sizeof(fmtdesc));
341 fmtdesc.type = buf_type;
342
343 for (; Ioctl(VIDIOC_ENUM_FMT, &fmtdesc) == 0; ++fmtdesc.index) {
344 DVLOG(1) << "Found " << fmtdesc.description << std::hex << " (0x"
345 << fmtdesc.pixelformat << ")";
346 pixelformats.push_back(fmtdesc.pixelformat);
347 }
348
349 return pixelformats;
350 }
351
352 VideoDecodeAccelerator::SupportedProfiles
EnumerateSupportedDecodeProfiles(const size_t num_formats,const uint32_t pixelformats[])353 V4L2Device::EnumerateSupportedDecodeProfiles(const size_t num_formats,
354 const uint32_t pixelformats[]) {
355 VideoDecodeAccelerator::SupportedProfiles profiles;
356
357 const auto& supported_pixelformats =
358 EnumerateSupportedPixelformats(V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE);
359
360 for (uint32_t pixelformat : supported_pixelformats) {
361 if (std::find(pixelformats, pixelformats + num_formats, pixelformat) ==
362 pixelformats + num_formats)
363 continue;
364
365 VideoDecodeAccelerator::SupportedProfile profile;
366 GetSupportedResolution(pixelformat, &profile.min_resolution,
367 &profile.max_resolution);
368
369 const auto video_codec_profiles =
370 V4L2PixFmtToVideoCodecProfiles(pixelformat, false);
371
372 for (const auto& video_codec_profile : video_codec_profiles) {
373 profile.profile = video_codec_profile;
374 profiles.push_back(profile);
375
376 DVLOG(1) << "Found decoder profile " << GetProfileName(profile.profile)
377 << ", resolutions: " << profile.min_resolution.ToString() << " "
378 << profile.max_resolution.ToString();
379 }
380 }
381
382 return profiles;
383 }
384
OpenDevicePath(const std::string & path,Type type)385 bool V4L2Device::OpenDevicePath(const std::string& path, Type type) {
386 DCHECK(!device_fd_.is_valid());
387
388 device_fd_.reset(
389 HANDLE_EINTR(open(path.c_str(), O_RDWR | O_NONBLOCK | O_CLOEXEC)));
390 if (!device_fd_.is_valid())
391 return false;
392
393 return true;
394 }
395
CloseDevice()396 void V4L2Device::CloseDevice() {
397 device_fd_.reset();
398 }
399
EnumerateDevicesForType(Type type)400 void V4L2Device::EnumerateDevicesForType(Type type) {
401 static const std::string kDecoderDevicePattern = "/dev/video-dec";
402 std::string device_pattern;
403 v4l2_buf_type buf_type;
404 switch (type) {
405 case Type::kDecoder:
406 device_pattern = kDecoderDevicePattern;
407 buf_type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
408 break;
409 default:
410 LOG(ERROR) << "Only decoder type is supported!!";
411 return;
412 }
413
414 std::vector<std::string> candidate_paths;
415
416 // TODO(posciak): Remove this legacy unnumbered device once
417 // all platforms are updated to use numbered devices.
418 candidate_paths.push_back(device_pattern);
419
420 // We are sandboxed, so we can't query directory contents to check which
421 // devices are actually available. Try to open the first 10; if not present,
422 // we will just fail to open immediately.
423 for (int i = 0; i < 10; ++i) {
424 candidate_paths.push_back(
425 base::StringPrintf("%s%d", device_pattern.c_str(), i));
426 }
427
428 Devices devices;
429 for (const auto& path : candidate_paths) {
430 if (!OpenDevicePath(path, type))
431 continue;
432
433 const auto& supported_pixelformats =
434 EnumerateSupportedPixelformats(buf_type);
435 if (!supported_pixelformats.empty()) {
436 DVLOG(1) << "Found device: " << path;
437 devices.push_back(std::make_pair(path, supported_pixelformats));
438 }
439
440 CloseDevice();
441 }
442
443 DCHECK_EQ(devices_by_type_.count(type), 0u);
444 devices_by_type_[type] = devices;
445 }
446
GetDevicesForType(Type type)447 const V4L2Device::Devices& V4L2Device::GetDevicesForType(Type type) {
448 if (devices_by_type_.count(type) == 0)
449 EnumerateDevicesForType(type);
450
451 DCHECK_NE(devices_by_type_.count(type), 0u);
452 return devices_by_type_[type];
453 }
454
GetDevicePathFor(Type type,uint32_t pixfmt)455 std::string V4L2Device::GetDevicePathFor(Type type, uint32_t pixfmt) {
456 const Devices& devices = GetDevicesForType(type);
457
458 for (const auto& device : devices) {
459 if (std::find(device.second.begin(), device.second.end(), pixfmt) !=
460 device.second.end())
461 return device.first;
462 }
463
464 return std::string();
465 }
466
467 } // namespace media
468