diff options
| -rw-r--r-- | include/libcamera/internal/v4l2_device.h | 1 | ||||
| -rw-r--r-- | src/libcamera/v4l2_device.cpp | 31 |
2 files changed, 32 insertions, 0 deletions
diff --git a/include/libcamera/internal/v4l2_device.h b/include/libcamera/internal/v4l2_device.h index bf643f2e..3b605aab 100644 --- a/include/libcamera/internal/v4l2_device.h +++ b/include/libcamera/internal/v4l2_device.h @@ -30,6 +30,7 @@ public: int setControls(ControlList *ctrls); const std::string &deviceNode() const { return deviceNode_; } + std::string devicePath() const; protected: V4L2Device(const std::string &deviceNode); diff --git a/src/libcamera/v4l2_device.cpp b/src/libcamera/v4l2_device.cpp index 56ea1ddd..65830d41 100644 --- a/src/libcamera/v4l2_device.cpp +++ b/src/libcamera/v4l2_device.cpp @@ -9,12 +9,15 @@ #include <fcntl.h> #include <iomanip> +#include <limits.h> +#include <stdlib.h> #include <string.h> #include <sys/ioctl.h> #include <sys/syscall.h> #include <unistd.h> #include "libcamera/internal/log.h" +#include "libcamera/internal/sysfs.h" #include "libcamera/internal/utils.h" #include "libcamera/internal/v4l2_controls.h" @@ -351,6 +354,34 @@ int V4L2Device::setControls(ControlList *ctrls) } /** + * \brief Retrieve the device path in sysfs + * + * This function returns the sysfs path to the physical device backing the V4L2 + * device. The path is guaranteed to be an absolute path, without any symbolic + * link. + * + * It includes the sysfs mount point prefix + * + * \return The device path in sysfs + */ +std::string V4L2Device::devicePath() const +{ + std::string devicePath = sysfs::charDevPath(deviceNode_) + "/device"; + + char *realPath = realpath(devicePath.c_str(), nullptr); + if (!realPath) { + LOG(V4L2, Fatal) + << "Can not resolve device path for " << devicePath; + return {}; + } + + std::string path{ realPath }; + free(realPath); + + return path; +} + +/** * \brief Perform an IOCTL system call on the device node * \param[in] request The IOCTL request code * \param[in] argp A pointer to the IOCTL argument |