2 * USB Serial Console driver
4 * Copyright (C) 2001 - 2002 Greg Kroah-Hartman (greg@kroah.com)
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License version
8 * 2 as published by the Free Software Foundation.
10 * Thanks to Randy Dunlap for the original version of this code.
14 #include <linux/kernel.h>
15 #include <linux/init.h>
16 #include <linux/slab.h>
17 #include <linux/tty.h>
18 #include <linux/console.h>
19 #include <linux/usb.h>
20 #include <linux/usb/serial.h>
27 struct usb_serial_port
*port
;
30 static struct usbcons_info usbcons_info
;
31 static struct console usbcons
;
34 * ------------------------------------------------------------
35 * USB Serial console driver
37 * Much of the code here is copied from drivers/char/serial.c
38 * and implements a phony serial console in the same way that
39 * serial.c does so that in case some software queries it,
40 * it will get the same results.
42 * Things that are different from the way the serial port code
43 * does things, is that we call the lower level usb-serial
44 * driver code to initialize the device, and we set the initial
45 * console speeds based on the command line arguments.
46 * ------------------------------------------------------------
51 * The parsing of the command line works exactly like the
52 * serial.c code, except that the specifier is "ttyUSB" instead
55 static int usb_console_setup(struct console
*co
, char *options
)
57 struct usbcons_info
*info
= &usbcons_info
;
62 int cflag
= CREAD
| HUPCL
| CLOCAL
;
64 struct usb_serial
*serial
;
65 struct usb_serial_port
*port
;
67 struct tty_struct
*tty
;
68 struct ktermios
*termios
;
70 dbg ("%s", __FUNCTION__
);
73 baud
= simple_strtoul(options
, NULL
, 10);
75 while (*s
>= '0' && *s
<= '9')
82 doflow
= (*s
++ == 'r');
85 /* build a cflag setting */
112 * Set this to a sane value to prevent a divide error
137 * no need to check the index here: if the index is wrong, console
140 serial
= usb_serial_get_by_index(co
->index
);
141 if (serial
== NULL
) {
142 /* no device is connected yet, sorry :( */
143 err ("No USB device connected to ttyUSB%i", co
->index
);
147 port
= serial
->port
[0];
153 if (port
->open_count
== 1) {
154 /* only call the device specific open if this
155 * is the first time the port is opened */
156 if (serial
->type
->open
)
157 retval
= serial
->type
->open(port
, NULL
);
159 retval
= usb_serial_generic_open(port
, NULL
);
161 port
->open_count
= 0;
165 err ("could not open USB console port");
169 if (serial
->type
->set_termios
) {
170 struct ktermios dummy
;
171 /* build up a fake tty structure so that the open call has something
172 * to look at to get the cflag value */
173 tty
= kzalloc(sizeof(*tty
), GFP_KERNEL
);
175 err ("no more memory");
178 termios
= kzalloc(sizeof(*termios
), GFP_KERNEL
);
180 err ("no more memory");
184 memset(&dummy
, 0, sizeof(struct ktermios
));
185 termios
->c_cflag
= cflag
;
186 tty
->termios
= termios
;
189 /* set up the initial termios settings */
190 serial
->type
->set_termios(port
, &dummy
);
200 static void usb_console_write(struct console
*co
, const char *buf
, unsigned count
)
202 static struct usbcons_info
*info
= &usbcons_info
;
203 struct usb_serial_port
*port
= info
->port
;
204 struct usb_serial
*serial
;
205 int retval
= -ENODEV
;
207 if (!port
|| port
->serial
->dev
->state
== USB_STATE_NOTATTACHED
)
209 serial
= port
->serial
;
214 dbg("%s - port %d, %d byte(s)", __FUNCTION__
, port
->number
, count
);
216 if (!port
->open_count
) {
217 dbg ("%s - port not opened", __FUNCTION__
);
224 /* search for LF so we can insert CR if necessary */
225 for (i
=0, lf
=0 ; i
< count
; i
++) {
226 if (*(buf
+ i
) == 10) {
232 /* pass on to the driver specific version of this function if it is available */
233 if (serial
->type
->write
)
234 retval
= serial
->type
->write(port
, buf
, i
);
236 retval
= usb_serial_generic_write(port
, buf
, i
);
237 dbg("%s - return value : %d", __FUNCTION__
, retval
);
239 /* append CR after LF */
240 unsigned char cr
= 13;
241 if (serial
->type
->write
)
242 retval
= serial
->type
->write(port
, &cr
, 1);
244 retval
= usb_serial_generic_write(port
, &cr
, 1);
245 dbg("%s - return value : %d", __FUNCTION__
, retval
);
252 static struct console usbcons
= {
254 .write
= usb_console_write
,
255 .setup
= usb_console_setup
,
256 .flags
= CON_PRINTBUFFER
,
260 void usb_serial_console_disconnect(struct usb_serial
*serial
)
262 if (serial
&& serial
->port
&& serial
->port
[0] && serial
->port
[0] == usbcons_info
.port
) {
263 usb_serial_console_exit();
264 usb_serial_put(serial
);
268 void usb_serial_console_init (int serial_debug
, int minor
)
270 debug
= serial_debug
;
274 * Call register_console() if this is the first device plugged
275 * in. If we call it earlier, then the callback to
276 * console_setup() will fail, as there is not a device seen by
277 * the USB subsystem yet.
282 * console_setup() is called (back) immediately (from register_console).
283 * console_write() is called immediately from register_console iff
284 * CON_PRINTBUFFER is set in flags.
286 dbg ("registering the USB serial console.");
287 register_console(&usbcons
);
291 void usb_serial_console_exit (void)
293 if (usbcons_info
.port
) {
294 unregister_console(&usbcons
);
295 if (usbcons_info
.port
->open_count
)
296 usbcons_info
.port
->open_count
--;
297 usbcons_info
.port
= NULL
;