diff options
Diffstat (limited to 'v4l2-apps/lib/libv4l/libv4l2/libv4l2.c')
| -rw-r--r-- | v4l2-apps/lib/libv4l/libv4l2/libv4l2.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/v4l2-apps/lib/libv4l/libv4l2/libv4l2.c b/v4l2-apps/lib/libv4l/libv4l2/libv4l2.c index fc41c665d..a40ab4ffe 100644 --- a/v4l2-apps/lib/libv4l/libv4l2/libv4l2.c +++ b/v4l2-apps/lib/libv4l/libv4l2/libv4l2.c @@ -75,6 +75,7 @@ #define V4L2_STREAMON 0x0100 #define V4L2_BUFFERS_REQUESTED_BY_READ 0x0200 #define V4L2_STREAM_CONTROLLED_BY_READ 0x0400 +#define V4L2_SUPPORTS_READ 0x0800 #define V4L2_MMAP_OFFSET_MAGIC 0xABCDEF00u @@ -456,6 +457,8 @@ int v4l2_fd_open(int fd, int v4l2_flags) } devices[index].flags = v4l2_flags; + if (cap.capabilities & V4L2_CAP_READWRITE) + devices[index].flags |= V4L2_SUPPORTS_READ; devices[index].open_count = 1; devices[index].src_fmt = fmt; devices[index].dest_fmt = fmt; @@ -908,6 +911,15 @@ ssize_t v4l2_read (int fd, void* buffer, size_t n) pthread_mutex_lock(&devices[index].stream_lock); + /* When not converting and the device supports read let the kernel handle + it */ + if ((devices[index].flags & V4L2_SUPPORTS_READ) && + devices[index].src_fmt.fmt.pix.pixelformat == + devices[index].dest_fmt.fmt.pix.pixelformat) { + result = syscall(SYS_read, fd, buffer, n); + goto leave; + } + if (!(devices[index].flags & V4L2_STREAM_CONTROLLED_BY_READ)) { if ((devices[index].flags & V4L2_STREAMON) || devices[index].frame_queued) { |