tty: Clarify documentation of ->write()
The tty driver write method is different to the usual fops device write
methods as the buffer is already in kernel space. Clarify the docs since
someone writing a driver made that mistake.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/Documentation/tty.txt b/Documentation/tty.txt
index 5f799e6..048a876 100644
--- a/Documentation/tty.txt
+++ b/Documentation/tty.txt
@@ -108,7 +108,9 @@
structure:
write() Write a block of characters to the tty device.
- Returns the number of characters accepted.
+ Returns the number of characters accepted. The
+ character buffer passed to this method is already
+ in kernel space.
put_char() Queues a character for writing to the tty device.
If there is no room in the queue, the character is