1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2000, 2002 Jeff Dike (jdike@karaya.com)
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 "chan.h"
16 #include <init.h>
17 #include <irq_user.h>
18 #include "mconsole_kern.h"
19
20 static const int ssl_version = 1;
21
22 #define NR_PORTS 64
23
ssl_announce(char * dev_name,int dev)24 static void ssl_announce(char *dev_name, int dev)
25 {
26 printk(KERN_INFO "Serial line %d assigned device '%s'\n", dev,
27 dev_name);
28 }
29
30 /* Almost const, except that xterm_title may be changed in an initcall */
31 static struct chan_opts opts = {
32 .announce = ssl_announce,
33 .xterm_title = "Serial Line #%d",
34 .raw = 1,
35 };
36
37 static int ssl_config(char *str, char **error_out);
38 static int ssl_get_config(char *dev, char *str, int size, char **error_out);
39 static int ssl_remove(int n, char **error_out);
40
41
42 /* Const, except for .mc.list */
43 static struct line_driver driver = {
44 .name = "UML serial line",
45 .device_name = "ttyS",
46 .major = TTY_MAJOR,
47 .minor_start = 64,
48 .type = TTY_DRIVER_TYPE_SERIAL,
49 .subtype = 0,
50 .read_irq = SSL_IRQ,
51 .read_irq_name = "ssl",
52 .write_irq = SSL_WRITE_IRQ,
53 .write_irq_name = "ssl-write",
54 .mc = {
55 .list = LIST_HEAD_INIT(driver.mc.list),
56 .name = "ssl",
57 .config = ssl_config,
58 .get_config = ssl_get_config,
59 .id = line_id,
60 .remove = ssl_remove,
61 },
62 };
63
64 /* The array is initialized by line_init, at initcall time. The
65 * elements are locked individually as needed.
66 */
67 static char *conf[NR_PORTS];
68 static char *def_conf = CONFIG_SSL_CHAN;
69 static struct line serial_lines[NR_PORTS];
70
ssl_config(char * str,char ** error_out)71 static int ssl_config(char *str, char **error_out)
72 {
73 return line_config(serial_lines, ARRAY_SIZE(serial_lines), str, &opts,
74 error_out);
75 }
76
ssl_get_config(char * dev,char * str,int size,char ** error_out)77 static int ssl_get_config(char *dev, char *str, int size, char **error_out)
78 {
79 return line_get_config(dev, serial_lines, ARRAY_SIZE(serial_lines), str,
80 size, error_out);
81 }
82
ssl_remove(int n,char ** error_out)83 static int ssl_remove(int n, char **error_out)
84 {
85 return line_remove(serial_lines, ARRAY_SIZE(serial_lines), n,
86 error_out);
87 }
88
ssl_install(struct tty_driver * driver,struct tty_struct * tty)89 static int ssl_install(struct tty_driver *driver, struct tty_struct *tty)
90 {
91 return line_install(driver, tty, &serial_lines[tty->index]);
92 }
93
94 static const struct tty_operations ssl_ops = {
95 .open = line_open,
96 .close = line_close,
97 .write = line_write,
98 .put_char = line_put_char,
99 .write_room = line_write_room,
100 .chars_in_buffer = line_chars_in_buffer,
101 .flush_buffer = line_flush_buffer,
102 .flush_chars = line_flush_chars,
103 .set_termios = line_set_termios,
104 .throttle = line_throttle,
105 .unthrottle = line_unthrottle,
106 .install = ssl_install,
107 .hangup = line_hangup,
108 };
109
110 /* Changed by ssl_init and referenced by ssl_exit, which are both serialized
111 * by being an initcall and exitcall, respectively.
112 */
113 static int ssl_init_done = 0;
114
ssl_console_write(struct console * c,const char * string,unsigned len)115 static void ssl_console_write(struct console *c, const char *string,
116 unsigned len)
117 {
118 struct line *line = &serial_lines[c->index];
119 unsigned long flags;
120
121 spin_lock_irqsave(&line->lock, flags);
122 console_write_chan(line->chan_out, string, len);
123 spin_unlock_irqrestore(&line->lock, flags);
124 }
125
ssl_console_device(struct console * c,int * index)126 static struct tty_driver *ssl_console_device(struct console *c, int *index)
127 {
128 *index = c->index;
129 return driver.driver;
130 }
131
ssl_console_setup(struct console * co,char * options)132 static int ssl_console_setup(struct console *co, char *options)
133 {
134 struct line *line = &serial_lines[co->index];
135
136 return console_open_chan(line, co);
137 }
138
139 /* No locking for register_console call - relies on single-threaded initcalls */
140 static struct console ssl_cons = {
141 .name = "ttyS",
142 .write = ssl_console_write,
143 .device = ssl_console_device,
144 .setup = ssl_console_setup,
145 .flags = CON_PRINTBUFFER|CON_ANYTIME,
146 .index = -1,
147 };
148
ssl_init(void)149 static int ssl_init(void)
150 {
151 char *new_title;
152 int err;
153 int i;
154
155 printk(KERN_INFO "Initializing software serial port version %d\n",
156 ssl_version);
157
158 err = register_lines(&driver, &ssl_ops, serial_lines,
159 ARRAY_SIZE(serial_lines));
160 if (err)
161 return err;
162
163 new_title = add_xterm_umid(opts.xterm_title);
164 if (new_title != NULL)
165 opts.xterm_title = new_title;
166
167 for (i = 0; i < NR_PORTS; i++) {
168 char *error;
169 char *s = conf[i];
170 if (!s)
171 s = def_conf;
172 if (setup_one_line(serial_lines, i, s, &opts, &error))
173 printk(KERN_ERR "setup_one_line failed for "
174 "device %d : %s\n", i, error);
175 }
176
177 ssl_init_done = 1;
178 register_console(&ssl_cons);
179 return 0;
180 }
181 late_initcall(ssl_init);
182
ssl_exit(void)183 static void ssl_exit(void)
184 {
185 if (!ssl_init_done)
186 return;
187 close_lines(serial_lines, ARRAY_SIZE(serial_lines));
188 }
189 __uml_exitcall(ssl_exit);
190
ssl_chan_setup(char * str)191 static int ssl_chan_setup(char *str)
192 {
193 line_setup(conf, NR_PORTS, &def_conf, str, "serial line");
194 return 1;
195 }
196
197 __setup("ssl", ssl_chan_setup);
198 __channel_help(ssl_chan_setup, "ssl");
199