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205 lines · 4.8 KiB

1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2000, 2002 Jeff Dike ([email protected])
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
20static const int ssl_version = 1;
21
22#define NR_PORTS 64
23
24static 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 */
31static struct chan_opts opts = {
32 .announce = ssl_announce,
33 .xterm_title = "Serial Line #%d",
34 .raw = 1,
35};
36
37static int ssl_config(char *str, char **error_out);
38static int ssl_get_config(char *dev, char *str, int size, char **error_out);
39static int ssl_remove(int n, char **error_out);
40
41
42/* Const, except for .mc.list */
43static 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 */
65static char *conf[NR_PORTS];
66static char *def_conf = CONFIG_SSL_CHAN;
67static struct line serial_lines[NR_PORTS];
68
69static 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
75static 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
81static 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
87static int ssl_install(struct tty_driver *driver, struct tty_struct *tty)
88{
89 return line_install(driver, tty, &serial_lines[tty->index]);
90}
91
92static 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 */
109static int ssl_init_done;
110
111static 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
122static struct tty_driver *ssl_console_device(struct console *c, int *index)
123{
124 *index = c->index;
125 return driver.driver;
126}
127
128static 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 */
136static 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
145static 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}
177late_initcall(ssl_init);
178
179static 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
187static 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
196static 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__uml_help(ssl_non_raw_setup,
203"ssl-non-raw\n"
204" Set serial lines to non-raw mode.\n\n"
205);