release/src-rt-6.x.4708/linux/linux-2.6.36/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 "kern.h"
  19 #include "init.h"
  20 #include "irq_user.h"
  21 #include "mconsole_kern.h"
  22
  23 static const int ssl_version = 1;
  24
  25 /* Referenced only by tty_driver below - presumably it's locked correctly
  26  * by the tty driver.
  27  */
  28
  29 static struct tty_driver *ssl_driver;
  30
  31 #define NR_PORTS 64
  32
  33 static void ssl_announce(char *dev_name, int dev)
  34 {
  35         printk(KERN_INFO "Serial line %d assigned device '%s'\n", dev,
  36                dev_name);
  37 }
  38
  39 /* Almost const, except that xterm_title may be changed in an initcall */
  40 static struct chan_opts opts = {
  41         .announce       = ssl_announce,
  42         .xterm_title    = "Serial Line #%d",
  43         .raw            = 1,
  44 };
  45
  46 static int ssl_config(char *str, char **error_out);
  47 static int ssl_get_config(char *dev, char *str, int size, char **error_out);
  48 static int ssl_remove(int n, char **error_out);
  49
  50
  51 /* Const, except for .mc.list */
  52 static struct line_driver driver = {
  53         .name                   = "UML serial line",
  54         .device_name            = "ttyS",
  55         .major                  = TTY_MAJOR,
  56         .minor_start            = 64,
  57         .type                   = TTY_DRIVER_TYPE_SERIAL,
  58         .subtype                = 0,
  59         .read_irq               = SSL_IRQ,
  60         .read_irq_name          = "ssl",
  61         .write_irq              = SSL_WRITE_IRQ,
  62         .write_irq_name         = "ssl-write",
  63         .mc  = {
  64                 .list           = LIST_HEAD_INIT(driver.mc.list),
  65                 .name           = "ssl",
  66                 .config         = ssl_config,
  67                 .get_config     = ssl_get_config,
  68                 .id             = line_id,
  69                 .remove         = ssl_remove,
  70         },
  71 };
  72
  73 /* The array is initialized by line_init, at initcall time.  The
  74  * elements are locked individually as needed.
  75  */
  76 static struct line serial_lines[NR_PORTS] =
  77         { [0 ... NR_PORTS - 1] = LINE_INIT(CONFIG_SSL_CHAN, &driver) };
  78
  79 static int ssl_config(char *str, char **error_out)
  80 {
  81         return line_config(serial_lines, ARRAY_SIZE(serial_lines), str, &opts,
  82                            error_out);
  83 }
  84
  85 static int ssl_get_config(char *dev, char *str, int size, char **error_out)
  86 {
  87         return line_get_config(dev, serial_lines, ARRAY_SIZE(serial_lines), str,
  88                                size, error_out);
  89 }
  90
  91 static int ssl_remove(int n, char **error_out)
  92 {
  93         return line_remove(serial_lines, ARRAY_SIZE(serial_lines), n,
  94                            error_out);
  95 }
  96
  97 static int ssl_open(struct tty_struct *tty, struct file *filp)
  98 {
  99         int err = line_open(serial_lines, tty);
 100
 101         if (err)
 102                 printk(KERN_ERR "Failed to open serial line %d, err = %d\n",
 103                        tty->index, err);
 104
 105         return err;
 106 }
 107
 108
 109 static const struct tty_operations ssl_ops = {
 110         .open                   = ssl_open,
 111         .close                  = line_close,
 112         .write                  = line_write,
 113         .put_char               = line_put_char,
 114         .write_room             = line_write_room,
 115         .chars_in_buffer        = line_chars_in_buffer,
 116         .flush_buffer           = line_flush_buffer,
 117         .flush_chars            = line_flush_chars,
 118         .set_termios            = line_set_termios,
 119         .ioctl                  = line_ioctl,
 120         .throttle               = line_throttle,
 121         .unthrottle             = line_unthrottle,
 122 };
 123
 124 /* Changed by ssl_init and referenced by ssl_exit, which are both serialized
 125  * by being an initcall and exitcall, respectively.
 126  */
 127 static int ssl_init_done = 0;
 128
 129 static void ssl_console_write(struct console *c, const char *string,
 130                               unsigned len)
 131 {
 132         struct line *line = &serial_lines[c->index];
 133         unsigned long flags;
 134
 135         spin_lock_irqsave(&line->lock, flags);
 136         console_write_chan(&line->chan_list, string, len);
 137         spin_unlock_irqrestore(&line->lock, flags);
 138 }
 139
 140 static struct tty_driver *ssl_console_device(struct console *c, int *index)
 141 {
 142         *index = c->index;
 143         return ssl_driver;
 144 }
 145
 146 static int ssl_console_setup(struct console *co, char *options)
 147 {
 148         struct line *line = &serial_lines[co->index];
 149
 150         return console_open_chan(line, co);
 151 }
 152
 153 /* No locking for register_console call - relies on single-threaded initcalls */
 154 static struct console ssl_cons = {
 155         .name           = "ttyS",
 156         .write          = ssl_console_write,
 157         .device         = ssl_console_device,
 158         .setup          = ssl_console_setup,
 159         .flags          = CON_PRINTBUFFER|CON_ANYTIME,
 160         .index          = -1,
 161 };
 162
 163 static int ssl_init(void)
 164 {
 165         char *new_title;
 166
 167         printk(KERN_INFO "Initializing software serial port version %d\n",
 168                ssl_version);
 169         ssl_driver = register_lines(&driver, &ssl_ops, serial_lines,
 170                                     ARRAY_SIZE(serial_lines));
 171
 172         new_title = add_xterm_umid(opts.xterm_title);
 173         if (new_title != NULL)
 174                 opts.xterm_title = new_title;
 175
 176         lines_init(serial_lines, ARRAY_SIZE(serial_lines), &opts);
 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         char *error;
 195         int ret;
 196
 197         ret = line_setup(serial_lines, ARRAY_SIZE(serial_lines), str, &error);
 198         if(ret < 0)
 199                 printk(KERN_ERR "Failed to set up serial line with "
 200                        "configuration string \"%s\" : %s\n", str, error);
 201
 202         return 1;
 203 }
 204
 205 __setup("ssl", ssl_chan_setup);
 206 __channel_help(ssl_chan_setup, "ssl");