xref: /openbmc/linux/arch/um/drivers/ssl.c (revision 615c36f5)
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 /* Referenced only by tty_driver below - presumably it's locked correctly
24  * by the tty driver.
25  */
26 
27 static struct tty_driver *ssl_driver;
28 
29 #define NR_PORTS 64
30 
31 static void ssl_announce(char *dev_name, int dev)
32 {
33 	printk(KERN_INFO "Serial line %d assigned device '%s'\n", dev,
34 	       dev_name);
35 }
36 
37 /* Almost const, except that xterm_title may be changed in an initcall */
38 static struct chan_opts opts = {
39 	.announce 	= ssl_announce,
40 	.xterm_title	= "Serial Line #%d",
41 	.raw		= 1,
42 };
43 
44 static int ssl_config(char *str, char **error_out);
45 static int ssl_get_config(char *dev, char *str, int size, char **error_out);
46 static int ssl_remove(int n, char **error_out);
47 
48 
49 /* Const, except for .mc.list */
50 static struct line_driver driver = {
51 	.name 			= "UML serial line",
52 	.device_name 		= "ttyS",
53 	.major 			= TTY_MAJOR,
54 	.minor_start 		= 64,
55 	.type 		 	= TTY_DRIVER_TYPE_SERIAL,
56 	.subtype 	 	= 0,
57 	.read_irq 		= SSL_IRQ,
58 	.read_irq_name 		= "ssl",
59 	.write_irq 		= SSL_WRITE_IRQ,
60 	.write_irq_name 	= "ssl-write",
61 	.mc  = {
62 		.list		= LIST_HEAD_INIT(driver.mc.list),
63 		.name  		= "ssl",
64 		.config 	= ssl_config,
65 		.get_config 	= ssl_get_config,
66 		.id		= line_id,
67 		.remove 	= ssl_remove,
68 	},
69 };
70 
71 /* The array is initialized by line_init, at initcall time.  The
72  * elements are locked individually as needed.
73  */
74 static struct line serial_lines[NR_PORTS] =
75 	{ [0 ... NR_PORTS - 1] = LINE_INIT(CONFIG_SSL_CHAN, &driver) };
76 
77 static int ssl_config(char *str, char **error_out)
78 {
79 	return line_config(serial_lines, ARRAY_SIZE(serial_lines), str, &opts,
80 			   error_out);
81 }
82 
83 static int ssl_get_config(char *dev, char *str, int size, char **error_out)
84 {
85 	return line_get_config(dev, serial_lines, ARRAY_SIZE(serial_lines), str,
86 			       size, error_out);
87 }
88 
89 static int ssl_remove(int n, char **error_out)
90 {
91 	return line_remove(serial_lines, ARRAY_SIZE(serial_lines), n,
92 			   error_out);
93 }
94 
95 static int ssl_open(struct tty_struct *tty, struct file *filp)
96 {
97 	int err = line_open(serial_lines, tty);
98 
99 	if (err)
100 		printk(KERN_ERR "Failed to open serial line %d, err = %d\n",
101 		       tty->index, err);
102 
103 	return err;
104 }
105 
106 #if 0
107 static void ssl_flush_buffer(struct tty_struct *tty)
108 {
109 	return;
110 }
111 
112 static void ssl_stop(struct tty_struct *tty)
113 {
114 	printk(KERN_ERR "Someone should implement ssl_stop\n");
115 }
116 
117 static void ssl_start(struct tty_struct *tty)
118 {
119 	printk(KERN_ERR "Someone should implement ssl_start\n");
120 }
121 
122 void ssl_hangup(struct tty_struct *tty)
123 {
124 }
125 #endif
126 
127 static const struct tty_operations ssl_ops = {
128 	.open 	 		= ssl_open,
129 	.close 	 		= line_close,
130 	.write 	 		= line_write,
131 	.put_char 		= line_put_char,
132 	.write_room		= line_write_room,
133 	.chars_in_buffer 	= line_chars_in_buffer,
134 	.flush_buffer 		= line_flush_buffer,
135 	.flush_chars 		= line_flush_chars,
136 	.set_termios 		= line_set_termios,
137 	.ioctl 	 		= line_ioctl,
138 	.throttle 		= line_throttle,
139 	.unthrottle 		= line_unthrottle,
140 #if 0
141 	.stop 	 		= ssl_stop,
142 	.start 	 		= ssl_start,
143 	.hangup 	 	= ssl_hangup,
144 #endif
145 };
146 
147 /* Changed by ssl_init and referenced by ssl_exit, which are both serialized
148  * by being an initcall and exitcall, respectively.
149  */
150 static int ssl_init_done = 0;
151 
152 static void ssl_console_write(struct console *c, const char *string,
153 			      unsigned len)
154 {
155 	struct line *line = &serial_lines[c->index];
156 	unsigned long flags;
157 
158 	spin_lock_irqsave(&line->lock, flags);
159 	console_write_chan(&line->chan_list, string, len);
160 	spin_unlock_irqrestore(&line->lock, flags);
161 }
162 
163 static struct tty_driver *ssl_console_device(struct console *c, int *index)
164 {
165 	*index = c->index;
166 	return ssl_driver;
167 }
168 
169 static int ssl_console_setup(struct console *co, char *options)
170 {
171 	struct line *line = &serial_lines[co->index];
172 
173 	return console_open_chan(line, co);
174 }
175 
176 /* No locking for register_console call - relies on single-threaded initcalls */
177 static struct console ssl_cons = {
178 	.name		= "ttyS",
179 	.write		= ssl_console_write,
180 	.device		= ssl_console_device,
181 	.setup		= ssl_console_setup,
182 	.flags		= CON_PRINTBUFFER|CON_ANYTIME,
183 	.index		= -1,
184 };
185 
186 static int ssl_init(void)
187 {
188 	char *new_title;
189 
190 	printk(KERN_INFO "Initializing software serial port version %d\n",
191 	       ssl_version);
192 	ssl_driver = register_lines(&driver, &ssl_ops, serial_lines,
193 				    ARRAY_SIZE(serial_lines));
194 
195 	new_title = add_xterm_umid(opts.xterm_title);
196 	if (new_title != NULL)
197 		opts.xterm_title = new_title;
198 
199 	lines_init(serial_lines, ARRAY_SIZE(serial_lines), &opts);
200 
201 	ssl_init_done = 1;
202 	register_console(&ssl_cons);
203 	return 0;
204 }
205 late_initcall(ssl_init);
206 
207 static void ssl_exit(void)
208 {
209 	if (!ssl_init_done)
210 		return;
211 	close_lines(serial_lines, ARRAY_SIZE(serial_lines));
212 }
213 __uml_exitcall(ssl_exit);
214 
215 static int ssl_chan_setup(char *str)
216 {
217 	char *error;
218 	int ret;
219 
220 	ret = line_setup(serial_lines, ARRAY_SIZE(serial_lines), str, &error);
221 	if(ret < 0)
222 		printk(KERN_ERR "Failed to set up serial line with "
223 		       "configuration string \"%s\" : %s\n", str, error);
224 
225 	return 1;
226 }
227 
228 __setup("ssl", ssl_chan_setup);
229 __channel_help(ssl_chan_setup, "ssl");
230