Pull misc-for-upstream into release branch
[linux-2.6] / arch / um / drivers / stdio_console.c
1 /* 
2  * Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com)
3  * Licensed under the GPL
4  */
5
6 #include "linux/posix_types.h"
7 #include "linux/tty.h"
8 #include "linux/tty_flip.h"
9 #include "linux/types.h"
10 #include "linux/major.h"
11 #include "linux/kdev_t.h"
12 #include "linux/console.h"
13 #include "linux/string.h"
14 #include "linux/sched.h"
15 #include "linux/list.h"
16 #include "linux/init.h"
17 #include "linux/interrupt.h"
18 #include "linux/slab.h"
19 #include "linux/hardirq.h"
20 #include "asm/current.h"
21 #include "asm/irq.h"
22 #include "stdio_console.h"
23 #include "line.h"
24 #include "chan_kern.h"
25 #include "user_util.h"
26 #include "kern_util.h"
27 #include "irq_user.h"
28 #include "mconsole_kern.h"
29 #include "init.h"
30
31 #define MAX_TTYS (16)
32
33 /* Referenced only by tty_driver below - presumably it's locked correctly
34  * by the tty driver.
35  */
36
37 static struct tty_driver *console_driver;
38
39 void stdio_announce(char *dev_name, int dev)
40 {
41         printk(KERN_INFO "Virtual console %d assigned device '%s'\n", dev,
42                dev_name);
43 }
44
45 /* Almost const, except that xterm_title may be changed in an initcall */
46 static struct chan_opts opts = {
47         .announce       = stdio_announce,
48         .xterm_title    = "Virtual Console #%d",
49         .raw            = 1,
50         .tramp_stack    = 0,
51         .in_kernel      = 1,
52 };
53
54 static int con_config(char *str, char **error_out);
55 static int con_get_config(char *dev, char *str, int size, char **error_out);
56 static int con_remove(int n, char **con_remove);
57
58
59 /* Const, except for .mc.list */
60 static struct line_driver driver = {
61         .name                   = "UML console",
62         .device_name            = "tty",
63         .major                  = TTY_MAJOR,
64         .minor_start            = 0,
65         .type                   = TTY_DRIVER_TYPE_CONSOLE,
66         .subtype                = SYSTEM_TYPE_CONSOLE,
67         .read_irq               = CONSOLE_IRQ,
68         .read_irq_name          = "console",
69         .write_irq              = CONSOLE_WRITE_IRQ,
70         .write_irq_name         = "console-write",
71         .mc  = {
72                 .list           = LIST_HEAD_INIT(driver.mc.list),
73                 .name           = "con",
74                 .config         = con_config,
75                 .get_config     = con_get_config,
76                 .id             = line_id,
77                 .remove         = con_remove,
78         },
79 };
80
81 /* The array is initialized by line_init, at initcall time.  The
82  * elements are locked individually as needed.
83  */
84 static struct line vts[MAX_TTYS] = { LINE_INIT(CONFIG_CON_ZERO_CHAN, &driver),
85                                      [ 1 ... MAX_TTYS - 1 ] =
86                                      LINE_INIT(CONFIG_CON_CHAN, &driver) };
87
88 static int con_config(char *str, char **error_out)
89 {
90         return line_config(vts, ARRAY_SIZE(vts), str, &opts, error_out);
91 }
92
93 static int con_get_config(char *dev, char *str, int size, char **error_out)
94 {
95         return line_get_config(dev, vts, ARRAY_SIZE(vts), str, size, error_out);
96 }
97
98 static int con_remove(int n, char **error_out)
99 {
100         return line_remove(vts, ARRAY_SIZE(vts), n, error_out);
101 }
102
103 static int con_open(struct tty_struct *tty, struct file *filp)
104 {
105         return line_open(vts, tty);
106 }
107
108 /* Set in an initcall, checked in an exitcall */
109 static int con_init_done = 0;
110
111 static const struct tty_operations console_ops = {
112         .open                   = con_open,
113         .close                  = line_close,
114         .write                  = line_write,
115         .put_char               = line_put_char,
116         .write_room             = line_write_room,
117         .chars_in_buffer        = line_chars_in_buffer,
118         .flush_buffer           = line_flush_buffer,
119         .flush_chars            = line_flush_chars,
120         .set_termios            = line_set_termios,
121         .ioctl                  = line_ioctl,
122         .throttle               = line_throttle,
123         .unthrottle             = line_unthrottle,
124 };
125
126 static void uml_console_write(struct console *console, const char *string,
127                               unsigned len)
128 {
129         struct line *line = &vts[console->index];
130         unsigned long flags;
131
132         spin_lock_irqsave(&line->lock, flags);
133         console_write_chan(&line->chan_list, string, len);
134         spin_unlock_irqrestore(&line->lock, flags);
135 }
136
137 static struct tty_driver *uml_console_device(struct console *c, int *index)
138 {
139         *index = c->index;
140         return console_driver;
141 }
142
143 static int uml_console_setup(struct console *co, char *options)
144 {
145         struct line *line = &vts[co->index];
146
147         return console_open_chan(line, co);
148 }
149
150 /* No locking for register_console call - relies on single-threaded initcalls */
151 static struct console stdiocons = {
152         .name           = "tty",
153         .write          = uml_console_write,
154         .device         = uml_console_device,
155         .setup          = uml_console_setup,
156         .flags          = CON_PRINTBUFFER,
157         .index          = -1,
158 };
159
160 int stdio_init(void)
161 {
162         char *new_title;
163
164         console_driver = register_lines(&driver, &console_ops, vts,
165                                         ARRAY_SIZE(vts));
166         if (console_driver == NULL)
167                 return -1;
168         printk(KERN_INFO "Initialized stdio console driver\n");
169
170         lines_init(vts, ARRAY_SIZE(vts), &opts);
171
172         new_title = add_xterm_umid(opts.xterm_title);
173         if(new_title != NULL)
174                 opts.xterm_title = new_title;
175
176         con_init_done = 1;
177         register_console(&stdiocons);
178         return 0;
179 }
180 late_initcall(stdio_init);
181
182 static void console_exit(void)
183 {
184         if (!con_init_done)
185                 return;
186         close_lines(vts, ARRAY_SIZE(vts));
187 }
188 __uml_exitcall(console_exit);
189
190 static int console_chan_setup(char *str)
191 {
192         char *error;
193         int ret;
194
195         ret = line_setup(vts, ARRAY_SIZE(vts), str, &error);
196         if(ret < 0)
197                 printk(KERN_ERR "Failed to set up console with "
198                        "configuration string \"%s\" : %s\n", str, error);
199
200         return 1;
201 }
202 __setup("con", console_chan_setup);
203 __channel_help(console_chan_setup, "con");