tty: docs: serial/tty, add to ldisc methods
A small addition to the ldisc method descriptions.
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/Documentation/serial/tty.txt b/Documentation/serial/tty.txt
index 8e65c44..5e5349a 100644
--- a/Documentation/serial/tty.txt
+++ b/Documentation/serial/tty.txt
@@ -42,7 +42,8 @@
open() - Called when the line discipline is attached to
the terminal. No other call into the line
discipline for this tty will occur until it
- completes successfully. Can sleep.
+ completes successfully. Returning an error will
+ prevent the ldisc from being attached. Can sleep.
close() - This is called on a terminal when the line
discipline is being unplugged. At the point of
@@ -52,7 +53,7 @@
hangup() - Called when the tty line is hung up.
The line discipline should cease I/O to the tty.
No further calls into the ldisc code will occur.
- Can sleep.
+ The return value is ignored. Can sleep.
write() - A process is writing data through the line
discipline. Multiple write calls are serialized
@@ -83,6 +84,10 @@
that might be for the ldisc. Multiple ioctl calls
may occur in parallel. May sleep.
+compat_ioctl() - Called when a 32 bit ioctl is handed to the tty layer
+ that might be for the ldisc. Multiple ioctl calls
+ may occur in parallel. May sleep.
+
Driver Side Interfaces:
receive_buf() - Hand buffers of bytes from the driver to the ldisc