[PATCH] doc: more serial-console info

Add info on flow control for serial consoles.  Refer to netconsole option
also.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 44a25f3..f8cb55c 100644 (file)
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -367,12 +367,17 @@ running once the system is up.
                tty<n>  Use the virtual console device <n>.
 
                ttyS<n>[,options]
+               ttyUSB0[,options]
                        Use the specified serial port.  The options are of
-                       the form "bbbbpn", where "bbbb" is the baud rate,
-                       "p" is parity ("n", "o", or "e"), and "n" is bits.
-                       Default is "9600n8".
-
-                       See also Documentation/serial-console.txt.
+                       the form "bbbbpnf", where "bbbb" is the baud rate,
+                       "p" is parity ("n", "o", or "e"), "n" is number of
+                       bits, and "f" is flow control ("r" for RTS or
+                       omit it).  Default is "9600n8".
+
+                       See Documentation/serial-console.txt for more
+                       information.  See
+                       Documentation/networking/netconsole.txt for an
+                       alternative.
 
                uart,io,<addr>[,options]
                uart,mmio,<addr>[,options]

diff --git a/Documentation/serial-console.txt b/Documentation/serial-console.txt
index 6c689b0..9a7bc8b 100644 (file)
--- a/Documentation/serial-console.txt
+++ b/Documentation/serial-console.txt
@@ -17,11 +17,13 @@ The format of this option is:
                        ttyX for any other virtual console
                        ttySx for a serial port
                        lp0 for the first parallel port
+                       ttyUSB0 for the first USB serial device
 
        options:        depend on the driver. For the serial port this
-                       defines the baudrate/parity/bits of the port,
-                       in the format BBBBPN, where BBBB is the speed,
-                       P is parity (n/o/e), and N is bits. Default is
+                       defines the baudrate/parity/bits/flow control of
+                       the port, in the format BBBBPNF, where BBBB is the
+                       speed, P is parity (n/o/e), N is number of bits,
+                       and F is flow control ('r' for RTS). Default is
                        9600n8. The maximum baudrate is 115200.
 
 You can specify multiple console= options on the kernel command line.
@@ -45,6 +47,9 @@ become the console.
 You will need to create a new device to use /dev/console. The official
 /dev/console is now character device 5,1.
 
+(You can also use a network device as a console.  See
+Documentation/networking/netconsole.txt for information on that.)
+
 Here's an example that will use /dev/ttyS1 (COM2) as the console.
 Replace the sample values as needed.