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 "line.h"
  16 #include "ssl.h"
  17 #include "chan_kern.h"
  18 #include "user_util.h"
  19 #include "kern_util.h"
  20 #include "kern.h"
  21 #include "init.h"
  22 #include "irq_user.h"
  23 #include "mconsole_kern.h"
  24
  25 static const int ssl_version = 1;
  26
  27 /* Referenced only by tty_driver below - presumably it's locked correctly
  28  * by the tty driver.
  29  */
  30
  31 static struct tty_driver *ssl_driver;
  32
  33 #define NR_PORTS 64
  34
  35 static void ssl_announce(char *dev_name, int dev)
  36 {
  37         printk(KERN_INFO "Serial line %d assigned device '%s'\n", dev,
  38                dev_name);
  39 }
  40
  41 static struct chan_opts opts = {
  42         .announce       = ssl_announce,
  43         .xterm_title    = "Serial Line #%d",
  44         .raw            = 1,
  45         .tramp_stack    = 0,
  46         .in_kernel      = 1,
  47 };
  48
  49 static int ssl_config(char *str);
  50 static int ssl_get_config(char *dev, char *str, int size, char **error_out);
  51 static int ssl_remove(int n);
  52
  53 static struct line_driver driver = {
  54         .name                   = "UML serial line",
  55         .device_name            = "ttyS",
  56         .major                  = TTY_MAJOR,
  57         .minor_start            = 64,
  58         .type                   = TTY_DRIVER_TYPE_SERIAL,
  59         .subtype                = 0,
  60         .read_irq               = SSL_IRQ,
  61         .read_irq_name          = "ssl",
  62         .write_irq              = SSL_WRITE_IRQ,
  63         .write_irq_name         = "ssl-write",
  64         .symlink_from           = "serial",
  65         .symlink_to             = "tts",
  66         .mc  = {
  67                 .name           = "ssl",
  68                 .config         = ssl_config,
  69                 .get_config     = ssl_get_config,
  70                 .id             = line_id,
  71                 .remove         = ssl_remove,
  72         },
  73 };
  74
  75 /* The array is initialized by line_init, which is an initcall.  The
  76  * individual elements are protected by individual semaphores.
  77  */
  78 static struct line serial_lines[NR_PORTS] =
  79         { [0 ... NR_PORTS - 1] = LINE_INIT(CONFIG_SSL_CHAN, &driver) };
  80
  81 static struct lines lines = LINES_INIT(NR_PORTS);
  82
  83 static int ssl_config(char *str)
  84 {
  85         return line_config(serial_lines, ARRAY_SIZE(serial_lines), str, &opts);
  86 }
  87
  88 static int ssl_get_config(char *dev, char *str, int size, char **error_out)
  89 {
  90         return line_get_config(dev, serial_lines, ARRAY_SIZE(serial_lines), str,
  91                                size, error_out);
  92 }
  93
  94 static int ssl_remove(int n)
  95 {
  96         return line_remove(serial_lines, ARRAY_SIZE(serial_lines), n);
  97 }
  98
  99 static int ssl_open(struct tty_struct *tty, struct file *filp)
 100 {
 101         return line_open(serial_lines, tty);
 102 }
 103
 104 #if 0
 105 static void ssl_flush_buffer(struct tty_struct *tty)
 106 {
 107         return;
 108 }
 109
 110 static void ssl_stop(struct tty_struct *tty)
 111 {
 112         printk(KERN_ERR "Someone should implement ssl_stop\n");
 113 }
 114
 115 static void ssl_start(struct tty_struct *tty)
 116 {
 117         printk(KERN_ERR "Someone should implement ssl_start\n");
 118 }
 119
 120 void ssl_hangup(struct tty_struct *tty)
 121 {
 122 }
 123 #endif
 124
 125 static const struct tty_operations ssl_ops = {
 126         .open                   = ssl_open,
 127         .close                  = line_close,
 128         .write                  = line_write,
 129         .put_char               = line_put_char,
 130         .write_room             = line_write_room,
 131         .chars_in_buffer        = line_chars_in_buffer,
 132         .flush_buffer           = line_flush_buffer,
 133         .flush_chars            = line_flush_chars,
 134         .set_termios            = line_set_termios,
 135         .ioctl                  = line_ioctl,
 136         .throttle               = line_throttle,
 137         .unthrottle             = line_unthrottle,
 138 #if 0
 139         .stop                   = ssl_stop,
 140         .start                  = ssl_start,
 141         .hangup                 = ssl_hangup,
 142 #endif
 143 };
 144
 145 /* Changed by ssl_init and referenced by ssl_exit, which are both serialized
 146  * by being an initcall and exitcall, respectively.
 147  */
 148 static int ssl_init_done = 0;
 149
 150 static void ssl_console_write(struct console *c, const char *string,
 151                               unsigned len)
 152 {
 153         struct line *line = &serial_lines[c->index];
 154         unsigned long flags;
 155
 156         spin_lock_irqsave(&line->lock, flags);
 157         console_write_chan(&line->chan_list, string, len);
 158         spin_unlock_irqrestore(&line->lock, flags);
 159 }
 160
 161 static struct tty_driver *ssl_console_device(struct console *c, int *index)
 162 {
 163         *index = c->index;
 164         return ssl_driver;
 165 }
 166
 167 static int ssl_console_setup(struct console *co, char *options)
 168 {
 169         struct line *line = &serial_lines[co->index];
 170
 171         return console_open_chan(line, co, &opts);
 172 }
 173
 174 static struct console ssl_cons = {
 175         .name           = "ttyS",
 176         .write          = ssl_console_write,
 177         .device         = ssl_console_device,
 178         .setup          = ssl_console_setup,
 179         .flags          = CON_PRINTBUFFER,
 180         .index          = -1,
 181 };
 182
 183 static int ssl_init(void)
 184 {
 185         char *new_title;
 186
 187         printk(KERN_INFO "Initializing software serial port version %d\n",
 188                ssl_version);
 189         ssl_driver = line_register_devfs(&lines, &driver, &ssl_ops,
 190                                          serial_lines,
 191                                          ARRAY_SIZE(serial_lines));
 192
 193         lines_init(serial_lines, ARRAY_SIZE(serial_lines), &opts);
 194
 195         new_title = add_xterm_umid(opts.xterm_title);
 196         if (new_title != NULL)
 197                 opts.xterm_title = new_title;
 198
 199         ssl_init_done = 1;
 200         register_console(&ssl_cons);
 201         return 0;
 202 }
 203 late_initcall(ssl_init);
 204
 205 static void ssl_exit(void)
 206 {
 207         if (!ssl_init_done)
 208                 return;
 209         close_lines(serial_lines, ARRAY_SIZE(serial_lines));
 210 }
 211 __uml_exitcall(ssl_exit);
 212
 213 static int ssl_chan_setup(char *str)
 214 {
 215         return line_setup(serial_lines, ARRAY_SIZE(serial_lines), str);
 216 }
 217
 218 __setup("ssl", ssl_chan_setup);
 219 __channel_help(ssl_chan_setup, "ssl");