xref: /openbmc/linux/arch/um/drivers/ssl.c (revision 22246614)
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 "kern.h"
19 #include "init.h"
20 #include "irq_user.h"
21 #include "mconsole_kern.h"
22 
23 static const int ssl_version = 1;
24 
25 /* Referenced only by tty_driver below - presumably it's locked correctly
26  * by the tty driver.
27  */
28 
29 static struct tty_driver *ssl_driver;
30 
31 #define NR_PORTS 64
32 
33 static void ssl_announce(char *dev_name, int dev)
34 {
35 	printk(KERN_INFO "Serial line %d assigned device '%s'\n", dev,
36 	       dev_name);
37 }
38 
39 /* Almost const, except that xterm_title may be changed in an initcall */
40 static struct chan_opts opts = {
41 	.announce 	= ssl_announce,
42 	.xterm_title	= "Serial Line #%d",
43 	.raw		= 1,
44 };
45 
46 static int ssl_config(char *str, char **error_out);
47 static int ssl_get_config(char *dev, char *str, int size, char **error_out);
48 static int ssl_remove(int n, char **error_out);
49 
50 
51 /* Const, except for .mc.list */
52 static struct line_driver driver = {
53 	.name 			= "UML serial line",
54 	.device_name 		= "ttyS",
55 	.major 			= TTY_MAJOR,
56 	.minor_start 		= 64,
57 	.type 		 	= TTY_DRIVER_TYPE_SERIAL,
58 	.subtype 	 	= 0,
59 	.read_irq 		= SSL_IRQ,
60 	.read_irq_name 		= "ssl",
61 	.write_irq 		= SSL_WRITE_IRQ,
62 	.write_irq_name 	= "ssl-write",
63 	.mc  = {
64 		.list		= LIST_HEAD_INIT(driver.mc.list),
65 		.name  		= "ssl",
66 		.config 	= ssl_config,
67 		.get_config 	= ssl_get_config,
68 		.id		= line_id,
69 		.remove 	= ssl_remove,
70 	},
71 };
72 
73 /* The array is initialized by line_init, at initcall time.  The
74  * elements are locked individually as needed.
75  */
76 static struct line serial_lines[NR_PORTS] =
77 	{ [0 ... NR_PORTS - 1] = LINE_INIT(CONFIG_SSL_CHAN, &driver) };
78 
79 static int ssl_config(char *str, char **error_out)
80 {
81 	return line_config(serial_lines, ARRAY_SIZE(serial_lines), str, &opts,
82 			   error_out);
83 }
84 
85 static int ssl_get_config(char *dev, char *str, int size, char **error_out)
86 {
87 	return line_get_config(dev, serial_lines, ARRAY_SIZE(serial_lines), str,
88 			       size, error_out);
89 }
90 
91 static int ssl_remove(int n, char **error_out)
92 {
93 	return line_remove(serial_lines, ARRAY_SIZE(serial_lines), n,
94 			   error_out);
95 }
96 
97 static int ssl_open(struct tty_struct *tty, struct file *filp)
98 {
99 	int err = line_open(serial_lines, tty);
100 
101 	if (err)
102 		printk(KERN_ERR "Failed to open serial line %d, err = %d\n",
103 		       tty->index, err);
104 
105 	return err;
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 /* No locking for register_console call - relies on single-threaded initcalls */
179 static struct console ssl_cons = {
180 	.name		= "ttyS",
181 	.write		= ssl_console_write,
182 	.device		= ssl_console_device,
183 	.setup		= ssl_console_setup,
184 	.flags		= CON_PRINTBUFFER|CON_ANYTIME,
185 	.index		= -1,
186 };
187 
188 static int ssl_init(void)
189 {
190 	char *new_title;
191 
192 	printk(KERN_INFO "Initializing software serial port version %d\n",
193 	       ssl_version);
194 	ssl_driver = register_lines(&driver, &ssl_ops, serial_lines,
195 				    ARRAY_SIZE(serial_lines));
196 
197 	new_title = add_xterm_umid(opts.xterm_title);
198 	if (new_title != NULL)
199 		opts.xterm_title = new_title;
200 
201 	lines_init(serial_lines, ARRAY_SIZE(serial_lines), &opts);
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");
232