[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
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -367,12 +367,17 @@
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".
+ 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 also Documentation/serial-console.txt.
+ 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
--- a/Documentation/serial-console.txt
+++ b/Documentation/serial-console.txt
@@ -17,11 +17,13 @@
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 @@
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.