kernel/arch/um/drivers/ssl.c

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