[PATCH] uml: mostly const a structure
[safe/jmp/linux-2.6] / arch / um / drivers / ssl.c
1 /* 
2  * Copyright (C) 2000, 2002 Jeff Dike (jdike@karaya.com)
3  * Licensed under the GPL
4  */
5
6 #include "linux/fs.h"
7 #include "linux/tty.h"
8 #include "linux/tty_driver.h"
9 #include "linux/major.h"
10 #include "linux/mm.h"
11 #include "linux/init.h"
12 #include "linux/console.h"
13 #include "asm/termbits.h"
14 #include "asm/irq.h"
15 #include "line.h"
16 #include "ssl.h"
17 #include "chan_kern.h"
18 #include "user_util.h"
19 #include "kern_util.h"
20 #include "kern.h"
21 #include "init.h"
22 #include "irq_user.h"
23 #include "mconsole_kern.h"
24
25 static const int ssl_version = 1;
26
27 /* Referenced only by tty_driver below - presumably it's locked correctly
28  * by the tty driver.
29  */
30
31 static struct tty_driver *ssl_driver;
32
33 #define NR_PORTS 64
34
35 static void ssl_announce(char *dev_name, int dev)
36 {
37         printk(KERN_INFO "Serial line %d assigned device '%s'\n", dev,
38                dev_name);
39 }
40
41 /* Almost const, except that xterm_title may be changed in an initcall */
42 static struct chan_opts opts = {
43         .announce       = ssl_announce,
44         .xterm_title    = "Serial Line #%d",
45         .raw            = 1,
46         .tramp_stack    = 0,
47         .in_kernel      = 1,
48 };
49
50 static int ssl_config(char *str, char **error_out);
51 static int ssl_get_config(char *dev, char *str, int size, char **error_out);
52 static int ssl_remove(int n, char **error_out);
53
54 static struct line_driver driver = {
55         .name                   = "UML serial line",
56         .device_name            = "ttyS",
57         .major                  = TTY_MAJOR,
58         .minor_start            = 64,
59         .type                   = TTY_DRIVER_TYPE_SERIAL,
60         .subtype                = 0,
61         .read_irq               = SSL_IRQ,
62         .read_irq_name          = "ssl",
63         .write_irq              = SSL_WRITE_IRQ,
64         .write_irq_name         = "ssl-write",
65         .symlink_from           = "serial",
66         .symlink_to             = "tts",
67         .mc  = {
68                 .list           = LIST_HEAD_INIT(driver.mc.list),
69                 .name           = "ssl",
70                 .config         = ssl_config,
71                 .get_config     = ssl_get_config,
72                 .id             = line_id,
73                 .remove         = ssl_remove,
74         },
75 };
76
77 /* The array is initialized by line_init, which is an initcall.  The 
78  * individual elements are protected by individual semaphores.
79  */
80 static struct line serial_lines[NR_PORTS] =
81         { [0 ... NR_PORTS - 1] = LINE_INIT(CONFIG_SSL_CHAN, &driver) };
82
83 static struct lines lines = LINES_INIT(NR_PORTS);
84
85 static int ssl_config(char *str, char **error_out)
86 {
87         return line_config(serial_lines, ARRAY_SIZE(serial_lines), str, &opts,
88                            error_out);
89 }
90
91 static int ssl_get_config(char *dev, char *str, int size, char **error_out)
92 {
93         return line_get_config(dev, serial_lines, ARRAY_SIZE(serial_lines), str,
94                                size, error_out);
95 }
96
97 static int ssl_remove(int n, char **error_out)
98 {
99         return line_remove(serial_lines, ARRAY_SIZE(serial_lines), n,
100                            error_out);
101 }
102
103 static int ssl_open(struct tty_struct *tty, struct file *filp)
104 {
105         return line_open(serial_lines, tty);
106 }
107
108 #if 0
109 static void ssl_flush_buffer(struct tty_struct *tty)
110 {
111         return;
112 }
113
114 static void ssl_stop(struct tty_struct *tty)
115 {
116         printk(KERN_ERR "Someone should implement ssl_stop\n");
117 }
118
119 static void ssl_start(struct tty_struct *tty)
120 {
121         printk(KERN_ERR "Someone should implement ssl_start\n");
122 }
123
124 void ssl_hangup(struct tty_struct *tty)
125 {
126 }
127 #endif
128
129 static const struct tty_operations ssl_ops = {
130         .open                   = ssl_open,
131         .close                  = line_close,
132         .write                  = line_write,
133         .put_char               = line_put_char,
134         .write_room             = line_write_room,
135         .chars_in_buffer        = line_chars_in_buffer,
136         .flush_buffer           = line_flush_buffer,
137         .flush_chars            = line_flush_chars,
138         .set_termios            = line_set_termios,
139         .ioctl                  = line_ioctl,
140         .throttle               = line_throttle,
141         .unthrottle             = line_unthrottle,
142 #if 0
143         .stop                   = ssl_stop,
144         .start                  = ssl_start,
145         .hangup                 = ssl_hangup,
146 #endif
147 };
148
149 /* Changed by ssl_init and referenced by ssl_exit, which are both serialized
150  * by being an initcall and exitcall, respectively.
151  */
152 static int ssl_init_done = 0;
153
154 static void ssl_console_write(struct console *c, const char *string,
155                               unsigned len)
156 {
157         struct line *line = &serial_lines[c->index];
158         unsigned long flags;
159
160         spin_lock_irqsave(&line->lock, flags);
161         console_write_chan(&line->chan_list, string, len);
162         spin_unlock_irqrestore(&line->lock, flags);
163 }
164
165 static struct tty_driver *ssl_console_device(struct console *c, int *index)
166 {
167         *index = c->index;
168         return ssl_driver;
169 }
170
171 static int ssl_console_setup(struct console *co, char *options)
172 {
173         struct line *line = &serial_lines[co->index];
174
175         return console_open_chan(line, co);
176 }
177
178 static struct console ssl_cons = {
179         .name           = "ttyS",
180         .write          = ssl_console_write,
181         .device         = ssl_console_device,
182         .setup          = ssl_console_setup,
183         .flags          = CON_PRINTBUFFER,
184         .index          = -1,
185 };
186
187 static int ssl_init(void)
188 {
189         char *new_title;
190
191         printk(KERN_INFO "Initializing software serial port version %d\n",
192                ssl_version);
193         ssl_driver = line_register_devfs(&lines, &driver, &ssl_ops,
194                                          serial_lines,
195                                          ARRAY_SIZE(serial_lines));
196
197         lines_init(serial_lines, ARRAY_SIZE(serial_lines), &opts);
198
199         new_title = add_xterm_umid(opts.xterm_title);
200         if (new_title != NULL)
201                 opts.xterm_title = new_title;
202
203         ssl_init_done = 1;
204         register_console(&ssl_cons);
205         return 0;
206 }
207 late_initcall(ssl_init);
208
209 static void ssl_exit(void)
210 {
211         if (!ssl_init_done)
212                 return;
213         close_lines(serial_lines, ARRAY_SIZE(serial_lines));
214 }
215 __uml_exitcall(ssl_exit);
216
217 static int ssl_chan_setup(char *str)
218 {
219         char *error;
220         int ret;
221
222         ret = line_setup(serial_lines, ARRAY_SIZE(serial_lines), str, &error);
223         if(ret < 0)
224                 printk(KERN_ERR "Failed to set up serial line with "
225                        "configuration string \"%s\" : %s\n", str, error);
226
227         return 1;
228 }
229
230 __setup("ssl", ssl_chan_setup);
231 __channel_help(ssl_chan_setup, "ssl");