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| author | hans@localhost.localdomain <hans@localhost.localdomain> | 2008-08-03 19:25:44 +0200 |
|---|---|---|
| committer | hans@localhost.localdomain <hans@localhost.localdomain> | 2008-08-03 19:25:44 +0200 |
| commit | 7ab958ab10b1a5c28dc0c0c798939c57e41e40a4 (patch) | |
| tree | d5cd3bf410fcf0394d94c4a7fefb6c0bd793484a /v4l2-apps/lib | |
| parent | a1c8635315d9fcc9768035549e3ff5ea61f1faf2 (diff) | |
| download | mediapointer-dvb-s2-7ab958ab10b1a5c28dc0c0c798939c57e41e40a4.tar.gz mediapointer-dvb-s2-7ab958ab10b1a5c28dc0c0c798939c57e41e40a4.tar.bz2 | |
libv4l: use driver read() when possible
From: Hans de Goede <j.w.r.degoede@hhs.nl>
When the driver supports read() and we are not converting let the driver
handle read() instead of emulating it with mmap mode
Signed-off-by: Hans de Goede <j.w.r.degoede@hhs.nl>
Diffstat (limited to 'v4l2-apps/lib')
| -rw-r--r-- | v4l2-apps/lib/libv4l/ChangeLog | 6 | ||||
| -rw-r--r-- | v4l2-apps/lib/libv4l/Makefile | 2 | ||||
| -rw-r--r-- | v4l2-apps/lib/libv4l/libv4l2/libv4l2.c | 12 |
3 files changed, 19 insertions, 1 deletions
diff --git a/v4l2-apps/lib/libv4l/ChangeLog b/v4l2-apps/lib/libv4l/ChangeLog index 675019bd2..3d4e40ad2 100644 --- a/v4l2-apps/lib/libv4l/ChangeLog +++ b/v4l2-apps/lib/libv4l/ChangeLog @@ -1,3 +1,9 @@ +libv4l-0.4.1 +------------ +* When the driver supports read() and we are not converting let the driver + handle read() instead of emulating it with mmap mode + + libv4l-0.4.0 ------------ * Be more relaxed in our checks for mixing read and mmap access, we were diff --git a/v4l2-apps/lib/libv4l/Makefile b/v4l2-apps/lib/libv4l/Makefile index 7f8867cd9..31254a09e 100644 --- a/v4l2-apps/lib/libv4l/Makefile +++ b/v4l2-apps/lib/libv4l/Makefile @@ -1,5 +1,5 @@ LIB_RELEASE=0 -V4L2_LIB_VERSION=$(LIB_RELEASE).4.0 +V4L2_LIB_VERSION=$(LIB_RELEASE).4.1 all clean install: $(MAKE) -C libv4lconvert V4L2_LIB_VERSION=$(V4L2_LIB_VERSION) $@ 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) { |