From 3ac40b9b5e62528d407e0e780b65c21c0247bc7c Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Wed, 28 Nov 2007 16:21:28 -0800 Subject: [PATCH] termios: document callback more clearly Signed-off-by: Alan Cox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/tty.txt | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/Documentation/tty.txt b/Documentation/tty.txt index 048a8762cfb5..8e65c4498c52 100644 --- a/Documentation/tty.txt +++ b/Documentation/tty.txt @@ -132,6 +132,14 @@ set_termios() Notify the tty driver that the device's termios tty->termios. Previous settings should be passed in the "old" argument. + The API is defined such that the driver should return + the actual modes selected. This means that the + driver function is responsible for modifying any + bits in the request it cannot fulfill to indicate + the actual modes being used. A device with no + hardware capability for change (eg a USB dongle or + virtual port) can provide NULL for this method. + throttle() Notify the tty driver that input buffers for the line discipline are close to full, and it should somehow signal that no more characters should be -- 2.20.1