xref: /openbmc/linux/arch/um/drivers/stdio_console.c (revision 1da177e4)
1 /*
2  * Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com)
3  * Licensed under the GPL
4  */
5 
6 #include "linux/config.h"
7 #include "linux/posix_types.h"
8 #include "linux/tty.h"
9 #include "linux/tty_flip.h"
10 #include "linux/types.h"
11 #include "linux/major.h"
12 #include "linux/kdev_t.h"
13 #include "linux/console.h"
14 #include "linux/string.h"
15 #include "linux/sched.h"
16 #include "linux/list.h"
17 #include "linux/init.h"
18 #include "linux/interrupt.h"
19 #include "linux/slab.h"
20 #include "linux/hardirq.h"
21 #include "asm/current.h"
22 #include "asm/irq.h"
23 #include "stdio_console.h"
24 #include "line.h"
25 #include "chan_kern.h"
26 #include "user_util.h"
27 #include "kern_util.h"
28 #include "irq_user.h"
29 #include "mconsole_kern.h"
30 #include "init.h"
31 #include "2_5compat.h"
32 
33 #define MAX_TTYS (16)
34 
35 /* ----------------------------------------------------------------------------- */
36 
37 /* Referenced only by tty_driver below - presumably it's locked correctly
38  * by the tty driver.
39  */
40 
41 static struct tty_driver *console_driver;
42 
43 void stdio_announce(char *dev_name, int dev)
44 {
45 	printk(KERN_INFO "Virtual console %d assigned device '%s'\n", dev,
46 	       dev_name);
47 }
48 
49 static struct chan_opts opts = {
50 	.announce 	= stdio_announce,
51 	.xterm_title	= "Virtual Console #%d",
52 	.raw		= 1,
53 	.tramp_stack 	= 0,
54 	.in_kernel 	= 1,
55 };
56 
57 static int con_config(char *str);
58 static int con_get_config(char *dev, char *str, int size, char **error_out);
59 static int con_remove(char *str);
60 
61 static struct line_driver driver = {
62 	.name 			= "UML console",
63 	.device_name 		= "tty",
64 	.devfs_name 		= "vc/",
65 	.major 			= TTY_MAJOR,
66 	.minor_start 		= 0,
67 	.type 		 	= TTY_DRIVER_TYPE_CONSOLE,
68 	.subtype 	 	= SYSTEM_TYPE_CONSOLE,
69 	.read_irq 		= CONSOLE_IRQ,
70 	.read_irq_name 		= "console",
71 	.write_irq 		= CONSOLE_WRITE_IRQ,
72 	.write_irq_name 	= "console-write",
73 	.symlink_from 		= "ttys",
74 	.symlink_to 		= "vc",
75 	.mc  = {
76 		.name  		= "con",
77 		.config 	= con_config,
78 		.get_config 	= con_get_config,
79 		.remove 	= con_remove,
80 	},
81 };
82 
83 static struct lines console_lines = LINES_INIT(MAX_TTYS);
84 
85 /* The array is initialized by line_init, which is an initcall.  The
86  * individual elements are protected by individual semaphores.
87  */
88 struct line vts[MAX_TTYS] = { LINE_INIT(CONFIG_CON_ZERO_CHAN, &driver),
89 			      [ 1 ... MAX_TTYS - 1 ] =
90 			      LINE_INIT(CONFIG_CON_CHAN, &driver) };
91 
92 static int con_config(char *str)
93 {
94 	return(line_config(vts, sizeof(vts)/sizeof(vts[0]), str));
95 }
96 
97 static int con_get_config(char *dev, char *str, int size, char **error_out)
98 {
99 	return(line_get_config(dev, vts, sizeof(vts)/sizeof(vts[0]), str,
100 			       size, error_out));
101 }
102 
103 static int con_remove(char *str)
104 {
105 	return(line_remove(vts, sizeof(vts)/sizeof(vts[0]), str));
106 }
107 
108 static int con_open(struct tty_struct *tty, struct file *filp)
109 {
110 	return line_open(vts, tty, &opts);
111 }
112 
113 static int con_init_done = 0;
114 
115 static struct tty_operations console_ops = {
116 	.open 	 		= con_open,
117 	.close 	 		= line_close,
118 	.write 	 		= line_write,
119  	.write_room		= line_write_room,
120 	.chars_in_buffer 	= line_chars_in_buffer,
121 	.set_termios 		= line_set_termios,
122 	.ioctl 	 		= line_ioctl,
123 };
124 
125 static void uml_console_write(struct console *console, const char *string,
126 			  unsigned len)
127 {
128 	struct line *line = &vts[console->index];
129 
130 	down(&line->sem);
131 	console_write_chan(&line->chan_list, string, len);
132 	up(&line->sem);
133 }
134 
135 static struct tty_driver *uml_console_device(struct console *c, int *index)
136 {
137 	*index = c->index;
138 	return console_driver;
139 }
140 
141 static int uml_console_setup(struct console *co, char *options)
142 {
143 	struct line *line = &vts[co->index];
144 
145 	return console_open_chan(line,co,&opts);
146 }
147 
148 static struct console stdiocons = {
149 	.name		= "tty",
150 	.write		= uml_console_write,
151 	.device		= uml_console_device,
152 	.setup		= uml_console_setup,
153 	.flags		= CON_PRINTBUFFER,
154 	.index		= -1,
155 	.data           = &vts,
156 };
157 
158 int stdio_init(void)
159 {
160 	char *new_title;
161 
162 	console_driver = line_register_devfs(&console_lines, &driver,
163 					     &console_ops, vts,
164 					     ARRAY_SIZE(vts));
165 	if (NULL == console_driver)
166 		return -1;
167 	printk(KERN_INFO "Initialized stdio console driver\n");
168 
169 	lines_init(vts, sizeof(vts)/sizeof(vts[0]));
170 
171 	new_title = add_xterm_umid(opts.xterm_title);
172 	if(new_title != NULL)
173 		opts.xterm_title = new_title;
174 
175 	con_init_done = 1;
176 	register_console(&stdiocons);
177 	return(0);
178 }
179 late_initcall(stdio_init);
180 
181 static void console_exit(void)
182 {
183 	if (!con_init_done)
184 		return;
185 	close_lines(vts, sizeof(vts)/sizeof(vts[0]));
186 }
187 __uml_exitcall(console_exit);
188 
189 static int console_chan_setup(char *str)
190 {
191 	return(line_setup(vts, sizeof(vts)/sizeof(vts[0]), str, 1));
192 }
193 __setup("con", console_chan_setup);
194 __channel_help(console_chan_setup, "con");
195 
196 /*
197  * Overrides for Emacs so that we follow Linus's tabbing style.
198  * Emacs will notice this stuff at the end of the file and automatically
199  * adjust the settings for this buffer only.  This must remain at the end
200  * of the file.
201  * ---------------------------------------------------------------------------
202  * Local variables:
203  * c-file-style: "linux"
204  * End:
205  */
206