xref: /openbmc/linux/arch/um/drivers/ssl.c (revision 95e9fd10)
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 "ssl.h"
16 #include "chan.h"
17 #include "init.h"
18 #include "irq_user.h"
19 #include "mconsole_kern.h"
20 
21 static const int ssl_version = 1;
22 
23 #define NR_PORTS 64
24 
25 static void ssl_announce(char *dev_name, int dev)
26 {
27 	printk(KERN_INFO "Serial line %d assigned device '%s'\n", dev,
28 	       dev_name);
29 }
30 
31 /* Almost const, except that xterm_title may be changed in an initcall */
32 static struct chan_opts opts = {
33 	.announce 	= ssl_announce,
34 	.xterm_title	= "Serial Line #%d",
35 	.raw		= 1,
36 };
37 
38 static int ssl_config(char *str, char **error_out);
39 static int ssl_get_config(char *dev, char *str, int size, char **error_out);
40 static int ssl_remove(int n, char **error_out);
41 
42 
43 /* Const, except for .mc.list */
44 static struct line_driver driver = {
45 	.name 			= "UML serial line",
46 	.device_name 		= "ttyS",
47 	.major 			= TTY_MAJOR,
48 	.minor_start 		= 64,
49 	.type 		 	= TTY_DRIVER_TYPE_SERIAL,
50 	.subtype 	 	= 0,
51 	.read_irq 		= SSL_IRQ,
52 	.read_irq_name 		= "ssl",
53 	.write_irq 		= SSL_WRITE_IRQ,
54 	.write_irq_name 	= "ssl-write",
55 	.mc  = {
56 		.list		= LIST_HEAD_INIT(driver.mc.list),
57 		.name  		= "ssl",
58 		.config 	= ssl_config,
59 		.get_config 	= ssl_get_config,
60 		.id		= line_id,
61 		.remove 	= ssl_remove,
62 	},
63 };
64 
65 /* The array is initialized by line_init, at initcall time.  The
66  * elements are locked individually as needed.
67  */
68 static char *conf[NR_PORTS];
69 static char *def_conf = CONFIG_SSL_CHAN;
70 static struct line serial_lines[NR_PORTS];
71 
72 static int ssl_config(char *str, char **error_out)
73 {
74 	return line_config(serial_lines, ARRAY_SIZE(serial_lines), str, &opts,
75 			   error_out);
76 }
77 
78 static int ssl_get_config(char *dev, char *str, int size, char **error_out)
79 {
80 	return line_get_config(dev, serial_lines, ARRAY_SIZE(serial_lines), str,
81 			       size, error_out);
82 }
83 
84 static int ssl_remove(int n, char **error_out)
85 {
86 	return line_remove(serial_lines, ARRAY_SIZE(serial_lines), n,
87 			   error_out);
88 }
89 
90 static int ssl_install(struct tty_driver *driver, struct tty_struct *tty)
91 {
92 	return line_install(driver, tty, &serial_lines[tty->index]);
93 }
94 
95 static const struct tty_operations ssl_ops = {
96 	.open 	 		= line_open,
97 	.close 	 		= line_close,
98 	.write 	 		= line_write,
99 	.put_char 		= line_put_char,
100 	.write_room		= line_write_room,
101 	.chars_in_buffer 	= line_chars_in_buffer,
102 	.flush_buffer 		= line_flush_buffer,
103 	.flush_chars 		= line_flush_chars,
104 	.set_termios 		= line_set_termios,
105 	.throttle 		= line_throttle,
106 	.unthrottle 		= line_unthrottle,
107 	.install		= ssl_install,
108 	.cleanup		= line_cleanup,
109 	.hangup			= line_hangup,
110 };
111 
112 /* Changed by ssl_init and referenced by ssl_exit, which are both serialized
113  * by being an initcall and exitcall, respectively.
114  */
115 static int ssl_init_done = 0;
116 
117 static void ssl_console_write(struct console *c, const char *string,
118 			      unsigned len)
119 {
120 	struct line *line = &serial_lines[c->index];
121 	unsigned long flags;
122 
123 	spin_lock_irqsave(&line->lock, flags);
124 	console_write_chan(line->chan_out, string, len);
125 	spin_unlock_irqrestore(&line->lock, flags);
126 }
127 
128 static struct tty_driver *ssl_console_device(struct console *c, int *index)
129 {
130 	*index = c->index;
131 	return driver.driver;
132 }
133 
134 static int ssl_console_setup(struct console *co, char *options)
135 {
136 	struct line *line = &serial_lines[co->index];
137 
138 	return console_open_chan(line, co);
139 }
140 
141 /* No locking for register_console call - relies on single-threaded initcalls */
142 static struct console ssl_cons = {
143 	.name		= "ttyS",
144 	.write		= ssl_console_write,
145 	.device		= ssl_console_device,
146 	.setup		= ssl_console_setup,
147 	.flags		= CON_PRINTBUFFER|CON_ANYTIME,
148 	.index		= -1,
149 };
150 
151 static int ssl_init(void)
152 {
153 	char *new_title;
154 	int err;
155 	int i;
156 
157 	printk(KERN_INFO "Initializing software serial port version %d\n",
158 	       ssl_version);
159 
160 	err = register_lines(&driver, &ssl_ops, serial_lines,
161 				    ARRAY_SIZE(serial_lines));
162 	if (err)
163 		return err;
164 
165 	new_title = add_xterm_umid(opts.xterm_title);
166 	if (new_title != NULL)
167 		opts.xterm_title = new_title;
168 
169 	for (i = 0; i < NR_PORTS; i++) {
170 		char *error;
171 		char *s = conf[i];
172 		if (!s)
173 			s = def_conf;
174 		if (setup_one_line(serial_lines, i, s, &opts, &error))
175 			printk(KERN_ERR "setup_one_line failed for "
176 			       "device %d : %s\n", i, error);
177 	}
178 
179 	ssl_init_done = 1;
180 	register_console(&ssl_cons);
181 	return 0;
182 }
183 late_initcall(ssl_init);
184 
185 static void ssl_exit(void)
186 {
187 	if (!ssl_init_done)
188 		return;
189 	close_lines(serial_lines, ARRAY_SIZE(serial_lines));
190 }
191 __uml_exitcall(ssl_exit);
192 
193 static int ssl_chan_setup(char *str)
194 {
195 	line_setup(conf, NR_PORTS, &def_conf, str, "serial line");
196 	return 1;
197 }
198 
199 __setup("ssl", ssl_chan_setup);
200 __channel_help(ssl_chan_setup, "ssl");
201