diff options
| -rw-r--r-- | src/cam/drm.cpp | 35 |
1 files changed, 27 insertions, 8 deletions
diff --git a/src/cam/drm.cpp b/src/cam/drm.cpp index b0602c94..2e4d7985 100644 --- a/src/cam/drm.cpp +++ b/src/cam/drm.cpp @@ -430,7 +430,8 @@ int Device::init() int Device::openCard() { const std::string dirName = "/dev/dri/"; - int ret = -ENOENT; + bool found = false; + int ret; /* * Open the first DRM/KMS device beginning with /dev/dri/card. The @@ -449,24 +450,42 @@ int Device::openCard() } for (struct dirent *res; (res = readdir(folder));) { + uint64_t cap; + if (strncmp(res->d_name, "card", 4)) continue; const std::string devName = dirName + res->d_name; fd_ = open(devName.c_str(), O_RDWR | O_CLOEXEC); - if (fd_ >= 0) { - ret = 0; - break; + if (fd_ < 0) { + ret = -errno; + std::cerr << "Failed to open DRM/KMS device " << devName << ": " + << strerror(-ret) << std::endl; + continue; } - ret = -errno; - std::cerr << "Failed to open DRM/KMS device " << devName << ": " - << strerror(-ret) << std::endl; + /* + * Skip devices that don't support the modeset API, to avoid + * selecting a DRM device corresponding to a GPU. There is no + * modeset capability, but the kernel returns an error for most + * caps if mode setting isn't support by the driver. The + * DRM_CAP_DUMB_BUFFER capability is one of those, other would + * do as well. The capability value itself isn't relevant. + */ + ret = drmGetCap(fd_, DRM_CAP_DUMB_BUFFER, &cap); + if (ret < 0) { + drmClose(fd_); + fd_ = -1; + continue; + } + + found = true; + break; } closedir(folder); - return ret; + return found ? 0 : -ENOENT; } int Device::getResources() |