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
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__channel_help(ssl_non_raw_setup, "set serial lines to non-raw mode");
203