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-rw-r--r--Documentation/ABI/stable/firewire-cdev69
1 files changed, 38 insertions, 31 deletions
diff --git a/Documentation/ABI/stable/firewire-cdev b/Documentation/ABI/stable/firewire-cdev
index f72ed653878a..261f85b13154 100644
--- a/Documentation/ABI/stable/firewire-cdev
+++ b/Documentation/ABI/stable/firewire-cdev
@@ -14,13 +14,17 @@ Description:
Each /dev/fw* is associated with one IEEE 1394 node, which can
be remote or local nodes. Operations on a /dev/fw* file have
different scope:
+
- The 1394 node which is associated with the file:
+
- Asynchronous request transmission
- Get the Configuration ROM
- Query node ID
- Query maximum speed of the path between this node
and local node
+
- The 1394 bus (i.e. "card") to which the node is attached to:
+
- Isochronous stream transmission and reception
- Asynchronous stream transmission and reception
- Asynchronous broadcast request transmission
@@ -31,7 +35,9 @@ Description:
manager
- Query cycle time
- Bus reset initiation, bus reset event reception
+
- All 1394 buses:
+
- Allocation of IEEE 1212 address ranges on the local
link layers, reception of inbound requests to such
an address range, asynchronous response transmission
@@ -43,6 +49,7 @@ Description:
userland implement different access permission models, some
operations are restricted to /dev/fw* files that are associated
with a local node:
+
- Addition of descriptors or directories to the local
nodes' Configuration ROM
- PHY packet transmission and reception
@@ -55,50 +62,50 @@ Description:
The following file operations are supported:
open(2)
- Currently the only useful flags are O_RDWR.
+ Currently the only useful flags are O_RDWR.
ioctl(2)
- Initiate various actions. Some take immediate effect, others
- are performed asynchronously while or after the ioctl returns.
- See the inline documentation in <linux/firewire-cdev.h> for
- descriptions of all ioctls.
+ Initiate various actions. Some take immediate effect, others
+ are performed asynchronously while or after the ioctl returns.
+ See the inline documentation in <linux/firewire-cdev.h> for
+ descriptions of all ioctls.
poll(2), select(2), epoll_wait(2) etc.
- Watch for events to become available to be read.
+ Watch for events to become available to be read.
read(2)
- Receive various events. There are solicited events like
- outbound asynchronous transaction completion or isochronous
- buffer completion, and unsolicited events such as bus resets,
- request reception, or PHY packet reception. Always use a read
- buffer which is large enough to receive the largest event that
- could ever arrive. See <linux/firewire-cdev.h> for descriptions
- of all event types and for which ioctls affect reception of
- events.
+ Receive various events. There are solicited events like
+ outbound asynchronous transaction completion or isochronous
+ buffer completion, and unsolicited events such as bus resets,
+ request reception, or PHY packet reception. Always use a read
+ buffer which is large enough to receive the largest event that
+ could ever arrive. See <linux/firewire-cdev.h> for descriptions
+ of all event types and for which ioctls affect reception of
+ events.
mmap(2)
- Allocate a DMA buffer for isochronous reception or transmission
- and map it into the process address space. The arguments should
- be used as follows: addr = NULL, length = the desired buffer
- size, i.e. number of packets times size of largest packet,
- prot = at least PROT_READ for reception and at least PROT_WRITE
- for transmission, flags = MAP_SHARED, fd = the handle to the
- /dev/fw*, offset = 0.
+ Allocate a DMA buffer for isochronous reception or transmission
+ and map it into the process address space. The arguments should
+ be used as follows: addr = NULL, length = the desired buffer
+ size, i.e. number of packets times size of largest packet,
+ prot = at least PROT_READ for reception and at least PROT_WRITE
+ for transmission, flags = MAP_SHARED, fd = the handle to the
+ /dev/fw*, offset = 0.
Isochronous reception works in packet-per-buffer fashion except
for multichannel reception which works in buffer-fill mode.
munmap(2)
- Unmap the isochronous I/O buffer from the process address space.
+ Unmap the isochronous I/O buffer from the process address space.
close(2)
- Besides stopping and freeing I/O contexts that were associated
- with the file descriptor, back out any changes to the local
- nodes' Configuration ROM. Deallocate isochronous channels and
- bandwidth at the IRM that were marked for kernel-assisted
- re- and deallocation.
-
-Users: libraw1394
- libdc1394
- libhinawa
+ Besides stopping and freeing I/O contexts that were associated
+ with the file descriptor, back out any changes to the local
+ nodes' Configuration ROM. Deallocate isochronous channels and
+ bandwidth at the IRM that were marked for kernel-assisted
+ re- and deallocation.
+
+Users: libraw1394;
+ libdc1394;
+ libhinawa;
tools like linux-firewire-utils, fwhack, ...