Merge branch 'intelfb-patches' of master.kernel.org:/pub/scm/linux/kernel/git/airlied...
[linux-2.6] / drivers / usb / serial / console.c
1 /*
2  * USB Serial Console driver
3  *
4  * Copyright (C) 2001 - 2002 Greg Kroah-Hartman (greg@kroah.com)
5  *
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.
9  * 
10  * Thanks to Randy Dunlap for the original version of this code.
11  *
12  */
13
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>
21
22 static int debug;
23
24 struct usbcons_info {
25         int                     magic;
26         int                     break_flag;
27         struct usb_serial_port  *port;
28 };
29
30 static struct usbcons_info usbcons_info;
31 static struct console usbcons;
32
33 /*
34  * ------------------------------------------------------------
35  * USB Serial console driver
36  *
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.
41  *
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  * ------------------------------------------------------------
47  */
48
49
50 /*
51  * The parsing of the command line works exactly like the
52  * serial.c code, except that the specifier is "ttyUSB" instead
53  * of "ttyS".
54  */
55 static int usb_console_setup(struct console *co, char *options)
56 {
57         struct usbcons_info *info = &usbcons_info;
58         int baud = 9600;
59         int bits = 8;
60         int parity = 'n';
61         int doflow = 0;
62         int cflag = CREAD | HUPCL | CLOCAL;
63         char *s;
64         struct usb_serial *serial;
65         struct usb_serial_port *port;
66         int retval = 0;
67         struct tty_struct *tty;
68         struct termios *termios;
69
70         dbg ("%s", __FUNCTION__);
71
72         if (options) {
73                 baud = simple_strtoul(options, NULL, 10);
74                 s = options;
75                 while (*s >= '0' && *s <= '9')
76                         s++;
77                 if (*s)
78                         parity = *s++;
79                 if (*s)
80                         bits   = *s++ - '0';
81                 if (*s)
82                         doflow = (*s++ == 'r');
83         }
84
85         /* build a cflag setting */
86         switch (baud) {
87                 case 1200:
88                         cflag |= B1200;
89                         break;
90                 case 2400:
91                         cflag |= B2400;
92                         break;
93                 case 4800:
94                         cflag |= B4800;
95                         break;
96                 case 19200:
97                         cflag |= B19200;
98                         break;
99                 case 38400:
100                         cflag |= B38400;
101                         break;
102                 case 57600:
103                         cflag |= B57600;
104                         break;
105                 case 115200:
106                         cflag |= B115200;
107                         break;
108                 case 9600:
109                 default:
110                         cflag |= B9600;
111                         /*
112                          * Set this to a sane value to prevent a divide error
113                          */
114                         baud  = 9600;
115                         break;
116         }
117         switch (bits) {
118                 case 7:
119                         cflag |= CS7;
120                         break;
121                 default:
122                 case 8:
123                         cflag |= CS8;
124                         break;
125         }
126         switch (parity) {
127                 case 'o': case 'O':
128                         cflag |= PARODD;
129                         break;
130                 case 'e': case 'E':
131                         cflag |= PARENB;
132                         break;
133         }
134         co->cflag = cflag;
135
136         /* grab the first serial port that happens to be connected */
137         serial = usb_serial_get_by_index(0);
138         if (serial == NULL) {
139                 /* no device is connected yet, sorry :( */
140                 err ("No USB device connected to ttyUSB0");
141                 return -ENODEV;
142         }
143
144         port = serial->port[0];
145         port->tty = NULL;
146
147         info->port = port;
148          
149         ++port->open_count;
150         if (port->open_count == 1) {
151                 /* only call the device specific open if this 
152                  * is the first time the port is opened */
153                 if (serial->type->open)
154                         retval = serial->type->open(port, NULL);
155                 else
156                         retval = usb_serial_generic_open(port, NULL);
157                 if (retval)
158                         port->open_count = 0;
159         }
160
161         if (retval) {
162                 err ("could not open USB console port");
163                 return retval;
164         }
165
166         if (serial->type->set_termios) {
167                 /* build up a fake tty structure so that the open call has something
168                  * to look at to get the cflag value */
169                 tty = kmalloc (sizeof (*tty), GFP_KERNEL);
170                 if (!tty) {
171                         err ("no more memory");
172                         return -ENOMEM;
173                 }
174                 termios = kmalloc (sizeof (*termios), GFP_KERNEL);
175                 if (!termios) {
176                         err ("no more memory");
177                         kfree (tty);
178                         return -ENOMEM;
179                 }
180                 memset (tty, 0x00, sizeof(*tty));
181                 memset (termios, 0x00, sizeof(*termios));
182                 termios->c_cflag = cflag;
183                 tty->termios = termios;
184                 port->tty = tty;
185
186                 /* set up the initial termios settings */
187                 serial->type->set_termios(port, NULL);
188                 port->tty = NULL;
189                 kfree (termios);
190                 kfree (tty);
191         }
192
193         return retval;
194 }
195
196 static void usb_console_write(struct console *co, const char *buf, unsigned count)
197 {
198         static struct usbcons_info *info = &usbcons_info;
199         struct usb_serial_port *port = info->port;
200         struct usb_serial *serial;
201         int retval = -ENODEV;
202
203         if (!port || port->serial->dev->state == USB_STATE_NOTATTACHED)
204                 return;
205         serial = port->serial;
206
207         if (count == 0)
208                 return;
209
210         dbg("%s - port %d, %d byte(s)", __FUNCTION__, port->number, count);
211
212         if (!port->open_count) {
213                 dbg ("%s - port not opened", __FUNCTION__);
214                 return;
215         }
216
217         while (count) {
218                 unsigned int i;
219                 unsigned int lf;
220                 /* search for LF so we can insert CR if necessary */
221                 for (i=0, lf=0 ; i < count ; i++) {
222                         if (*(buf + i) == 10) {
223                                 lf = 1;
224                                 i++;
225                                 break;
226                         }
227                 }
228                 /* pass on to the driver specific version of this function if it is available */
229                 if (serial->type->write)
230                         retval = serial->type->write(port, buf, i);
231                 else
232                         retval = usb_serial_generic_write(port, buf, i);
233                 dbg("%s - return value : %d", __FUNCTION__, retval);
234                 if (lf) {
235                         /* append CR after LF */
236                         unsigned char cr = 13;
237                         if (serial->type->write)
238                                 retval = serial->type->write(port, &cr, 1);
239                         else
240                                 retval = usb_serial_generic_write(port, &cr, 1);
241                         dbg("%s - return value : %d", __FUNCTION__, retval);
242                 }
243                 buf += i;
244                 count -= i;
245         }
246 }
247
248 static struct console usbcons = {
249         .name =         "ttyUSB",
250         .write =        usb_console_write,
251         .setup =        usb_console_setup,
252         .flags =        CON_PRINTBUFFER,
253         .index =        -1,
254 };
255
256 void usb_serial_console_disconnect(struct usb_serial *serial)
257 {
258         if (serial && serial->port && serial->port[0] && serial->port[0] == usbcons_info.port) {
259                 usb_serial_console_exit();
260                 usb_serial_put(serial);
261         }
262 }
263
264 void usb_serial_console_init (int serial_debug, int minor)
265 {
266         debug = serial_debug;
267
268         if (minor == 0) {
269                 /* 
270                  * Call register_console() if this is the first device plugged
271                  * in.  If we call it earlier, then the callback to
272                  * console_setup() will fail, as there is not a device seen by
273                  * the USB subsystem yet.
274                  */
275                 /*
276                  * Register console.
277                  * NOTES:
278                  * console_setup() is called (back) immediately (from register_console).
279                  * console_write() is called immediately from register_console iff
280                  * CON_PRINTBUFFER is set in flags.
281                  */
282                 dbg ("registering the USB serial console.");
283                 register_console(&usbcons);
284         }
285 }
286
287 void usb_serial_console_exit (void)
288 {
289         if (usbcons_info.port) {
290                 unregister_console(&usbcons);
291                 if (usbcons_info.port->open_count)
292                         usbcons_info.port->open_count--;
293                 usbcons_info.port = NULL;
294         }
295 }
296