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_name = "ssl",
51 .write_irq_name = "ssl-write",
52 .mc = {
53 .list = LIST_HEAD_INIT(driver.mc.list),
54 .name = "ssl",
55 .config = ssl_config,
56 .get_config = ssl_get_config,
57 .id = line_id,
58 .remove = ssl_remove,
59 },
60 };
61
62 /* The array is initialized by line_init, at initcall time. The
63 * elements are locked individually as needed.
64 */
65 static char *conf[NR_PORTS];
66 static char *def_conf = CONFIG_SSL_CHAN;
67 static struct line serial_lines[NR_PORTS];
68
ssl_config(char * str,char ** error_out)69 static int ssl_config(char *str, char **error_out)
70 {
71 return line_config(serial_lines, ARRAY_SIZE(serial_lines), str, &opts,
72 error_out);
73 }
74
ssl_get_config(char * dev,char * str,int size,char ** error_out)75 static int ssl_get_config(char *dev, char *str, int size, char **error_out)
76 {
77 return line_get_config(dev, serial_lines, ARRAY_SIZE(serial_lines), str,
78 size, error_out);
79 }
80
ssl_remove(int n,char ** error_out)81 static int ssl_remove(int n, char **error_out)
82 {
83 return line_remove(serial_lines, ARRAY_SIZE(serial_lines), n,
84 error_out);
85 }
86
ssl_install(struct tty_driver * driver,struct tty_struct * tty)87 static int ssl_install(struct tty_driver *driver, struct tty_struct *tty)
88 {
89 return line_install(driver, tty, &serial_lines[tty->index]);
90 }
91
92 static const struct tty_operations ssl_ops = {
93 .open = line_open,
94 .close = line_close,
95 .write = line_write,
96 .write_room = line_write_room,
97 .chars_in_buffer = line_chars_in_buffer,
98 .flush_buffer = line_flush_buffer,
99 .flush_chars = line_flush_chars,
100 .throttle = line_throttle,
101 .unthrottle = line_unthrottle,
102 .install = ssl_install,
103 .hangup = line_hangup,
104 };
105
106 /* Changed by ssl_init and referenced by ssl_exit, which are both serialized
107 * by being an initcall and exitcall, respectively.
108 */
109 static int ssl_init_done;
110
ssl_console_write(struct console * c,const char * string,unsigned len)111 static void ssl_console_write(struct console *c, const char *string,
112 unsigned len)
113 {
114 struct line *line = &serial_lines[c->index];
115 unsigned long flags;
116
117 spin_lock_irqsave(&line->lock, flags);
118 console_write_chan(line->chan_out, string, len);
119 spin_unlock_irqrestore(&line->lock, flags);
120 }
121
ssl_console_device(struct console * c,int * index)122 static struct tty_driver *ssl_console_device(struct console *c, int *index)
123 {
124 *index = c->index;
125 return driver.driver;
126 }
127
ssl_console_setup(struct console * co,char * options)128 static int ssl_console_setup(struct console *co, char *options)
129 {
130 struct line *line = &serial_lines[co->index];
131
132 return console_open_chan(line, co);
133 }
134
135 /* No locking for register_console call - relies on single-threaded initcalls */
136 static struct console ssl_cons = {
137 .name = "ttyS",
138 .write = ssl_console_write,
139 .device = ssl_console_device,
140 .setup = ssl_console_setup,
141 .flags = CON_PRINTBUFFER|CON_ANYTIME,
142 .index = -1,
143 };
144
ssl_init(void)145 static int ssl_init(void)
146 {
147 char *new_title;
148 int err;
149 int i;
150
151 printk(KERN_INFO "Initializing software serial port version %d\n",
152 ssl_version);
153
154 err = register_lines(&driver, &ssl_ops, serial_lines,
155 ARRAY_SIZE(serial_lines));
156 if (err)
157 return err;
158
159 new_title = add_xterm_umid(opts.xterm_title);
160 if (new_title != NULL)
161 opts.xterm_title = new_title;
162
163 for (i = 0; i < NR_PORTS; i++) {
164 char *error;
165 char *s = conf[i];
166 if (!s)
167 s = def_conf;
168 if (setup_one_line(serial_lines, i, s, &opts, &error))
169 printk(KERN_ERR "setup_one_line failed for "
170 "device %d : %s\n", i, error);
171 }
172
173 ssl_init_done = 1;
174 register_console(&ssl_cons);
175 return 0;
176 }
177 late_initcall(ssl_init);
178
ssl_exit(void)179 static void ssl_exit(void)
180 {
181 if (!ssl_init_done)
182 return;
183 close_lines(serial_lines, ARRAY_SIZE(serial_lines));
184 }
185 __uml_exitcall(ssl_exit);
186
ssl_chan_setup(char * str)187 static int ssl_chan_setup(char *str)
188 {
189 line_setup(conf, NR_PORTS, &def_conf, str, "serial line");
190 return 1;
191 }
192
193 __setup("ssl", ssl_chan_setup);
194 __channel_help(ssl_chan_setup, "ssl");
195
ssl_non_raw_setup(char * str)196 static int ssl_non_raw_setup(char *str)
197 {
198 opts.raw = 0;
199 return 1;
200 }
201 __setup("ssl-non-raw", ssl_non_raw_setup);
202 __channel_help(ssl_non_raw_setup, "set serial lines to non-raw mode");
203