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         .cleanup                = line_cleanup,
 109         .hangup                 = line_hangup,
 110 };
 111
 112 /* Changed by ssl_init and referenced by ssl_exit, which are both serialized
 113  * by being an initcall and exitcall, respectively.
 114  */
 115 static int ssl_init_done = 0;
 116
 117 static void ssl_console_write(struct console *c, const char *string,
 118                               unsigned len)
 119 {
 120         struct line *line = &serial_lines[c->index];
 121         unsigned long flags;
 122
 123         spin_lock_irqsave(&line->lock, flags);
 124         console_write_chan(line->chan_out, string, len);
 125         spin_unlock_irqrestore(&line->lock, flags);
 126 }
 127
 128 static struct tty_driver *ssl_console_device(struct console *c, int *index)
 129 {
 130         *index = c->index;
 131         return driver.driver;
 132 }
 133
 134 static int ssl_console_setup(struct console *co, char *options)
 135 {
 136         struct line *line = &serial_lines[co->index];
 137
 138         return console_open_chan(line, co);
 139 }
 140
 141 /* No locking for register_console call - relies on single-threaded initcalls */
 142 static struct console ssl_cons = {
 143         .name           = "ttyS",
 144         .write          = ssl_console_write,
 145         .device         = ssl_console_device,
 146         .setup          = ssl_console_setup,
 147         .flags          = CON_PRINTBUFFER|CON_ANYTIME,
 148         .index          = -1,
 149 };
 150
 151 static int ssl_init(void)
 152 {
 153         char *new_title;
 154         int err;
 155         int i;
 156
 157         printk(KERN_INFO "Initializing software serial port version %d\n",
 158                ssl_version);
 159
 160         err = register_lines(&driver, &ssl_ops, serial_lines,
 161                                     ARRAY_SIZE(serial_lines));
 162         if (err)
 163                 return err;
 164
 165         new_title = add_xterm_umid(opts.xterm_title);
 166         if (new_title != NULL)
 167                 opts.xterm_title = new_title;
 168
 169         for (i = 0; i < NR_PORTS; i++) {
 170                 char *error;
 171                 char *s = conf[i];
 172                 if (!s)
 173                         s = def_conf;
 174                 if (setup_one_line(serial_lines, i, s, &opts, &error))
 175                         printk(KERN_ERR "setup_one_line failed for "
 176                                "device %d : %s\n", i, error);
 177         }
 178
 179         ssl_init_done = 1;
 180         register_console(&ssl_cons);
 181         return 0;
 182 }
 183 late_initcall(ssl_init);
 184
 185 static void ssl_exit(void)
 186 {
 187         if (!ssl_init_done)
 188                 return;
 189         close_lines(serial_lines, ARRAY_SIZE(serial_lines));
 190 }
 191 __uml_exitcall(ssl_exit);
 192
 193 static int ssl_chan_setup(char *str)
 194 {
 195         line_setup(conf, NR_PORTS, &def_conf, str, "serial line");
 196         return 1;
 197 }
 198
 199 __setup("ssl", ssl_chan_setup);
 200 __channel_help(ssl_chan_setup, "ssl");