X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=Documentation%2Ftty.txt;h=8e65c4498c521259d93061e0a94a2d3652eaef98;hb=d1a35e4d74d070b06163e435e590ca90a2420b9e;hp=5f799e612e039f19f530090cd01161fdfc12c1ca;hpb=975a8e3ed2b9eab9f062a1e0ba7fe180e15204e1;p=linux-2.6-omap-h63xx.git

diff --git a/Documentation/tty.txt b/Documentation/tty.txt
index 5f799e612e0..8e65c4498c5 100644
--- a/Documentation/tty.txt
+++ b/Documentation/tty.txt
@@ -108,7 +108,9 @@ hardware driver through the function pointers within the tty->driver
 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
@@ -130,6 +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