libraw1394 fork
db5f202d5d
The kernel already read each node's Configuration ROM and cached it. So let all libraw1394 clients read from that cache instead of having to perform all those transactions all over again. This reduces bus traffic at application start-up and at each bus reset. It also makes all Configuration ROM accesses fool-proof and robust. This together with the kernel patch "firewire: core: handle ack_busy when fetching the Config ROM" lets me use an old Panasonic camcorder which requires us to keep pauses between response and request --- longer than librom1394's retry pause --- with dvgrab (though still with frequent failures of write requests to FCP_COMMAND, i.e. with lots of "send oops" noise in the console and occasionally having to repeat key-presses in interactive mode). For simplicity of implementation, only the blocking raw1394_read() is modified, not the nonblocking raw1394_start_read(). Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> Signed-off-by: Dan Dennedy <dan@dennedy.org> |
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| debian | ||
| doc | ||
| src | ||
| tools | ||
| AUTHORS | ||
| autogen.sh | ||
| ChangeLog | ||
| configure.ac | ||
| COPYING.LIB | ||
| INSTALL | ||
| libraw1394.pc.in | ||
| libraw1394.spec.in | ||
| Makefile.am | ||
| NEWS | ||
| README | ||
libraw1394 ========== 1. About libraw1394 libraw1394 is the only supported interface to the kernel side raw1394 of the Linux IEEE-1394 subsystem, which provides direct access to the connected 1394 buses to user space. Through libraw1394/raw1394, applications can directly send to and receive from other nodes without requiring a kernel driver for the protocol in question. The reason for making a library the interface to the kernel is to avoid a program dependency on the kernel version, which would hinder development and optimization of raw1394. If development changed the protocol and made it incompatible with previous versions only the libraw1394 has to be upgraded to match the kernel version (instead of all applications). Since version 2, libraw1394 also works with the kernel driver firewire-core. libraw1394's role has thus become that of a raw1394 compatibility layer for existing applications when running on firewire-core. 2. Copyleft libraw1394 itself is licensed under the Lesser General Public License (short LGPL, see file COPYING.LIB in the source distribution). Other files in the source archives not belonging to but being part of the build procedure of libraw1394 are under their own licenses, as stated at the top of the individual files. 3. API documentation Finally there is something, in the doc subdirectory. The file is libraw1394.sgml (it's Docbook format), and there are preformatted PostScript and HTML available. This documentation is not complete yet. 4. Multithreading This library should be multithreadable with the restriction that one raw1394handle_t may be used only within a single thread. Multiple threads operating on the same handle would royally mess up the kernel-user protocol. Simply use separate handles for each thread in which you need to use libraw1394. 5. Pkg-config The library comes with a pkg-config .pc file, so you can check for libraw1394 and its version in your configure script. For example, here is how to use the autoconf macro: PKG_CHECK_MODULES(LIBRAW1394, libraw1394 >= 1.1.0) This macro sets the variables LIBRAW1394_CFLAGS and LIBRAW1394_LIBS. You have to include those into your build variables so that the build process correctly links with libraw1394. 6. Contact Send questions, suggestions, bug reports and patches to the mailing list linux1394-devel@lists.sourceforge.net. This list is open for posting without prior subscription, and replies will usually be Cc'd to you. Visit http://ieee1394.wiki.kernel.org/ for links to list subscription interfaces and list archives. Maintainer of libraw1394 is currently Stefan Richter. See the file AUTHORS for a complete list of contributors to libraw1394. Source repository: git://git.kernel.org/pub/scm/libs/ieee1394/libraw1394.git http://git.kernel.org/pub/scm/libs/ieee1394/libraw1394.git https://git.kernel.org/pub/scm/libs/ieee1394/libraw1394.git Gitweb: http://git.kernel.org/?p=libs/ieee1394/libraw1394.git Release tarballs: https://www.kernel.org/pub/linux/libs/ieee1394/ ftp://ftp.kernel.org/pub/linux/libs/ieee1394/