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 #if 0
 109 static void ssl_flush_buffer(struct tty_struct *tty)
 110 {
 111         return;
 112 }
 113
 114 static void ssl_stop(struct tty_struct *tty)
 115 {
 116         printk(KERN_ERR "Someone should implement ssl_stop\n");
 117 }
 118
 119 static void ssl_start(struct tty_struct *tty)
 120 {
 121         printk(KERN_ERR "Someone should implement ssl_start\n");
 122 }
 123
 124 void ssl_hangup(struct tty_struct *tty)
 125 {
 126 }
 127 #endif
 128
 129 static const struct tty_operations ssl_ops = {
 130         .open                   = ssl_open,
 131         .close                  = line_close,
 132         .write                  = line_write,
 133         .put_char               = line_put_char,
 134         .write_room             = line_write_room,
 135         .chars_in_buffer        = line_chars_in_buffer,
 136         .flush_buffer           = line_flush_buffer,
 137         .flush_chars            = line_flush_chars,
 138         .set_termios            = line_set_termios,
 139         .ioctl                  = line_ioctl,
 140         .throttle               = line_throttle,
 141         .unthrottle             = line_unthrottle,
 142 #if 0
 143         .stop                   = ssl_stop,
 144         .start                  = ssl_start,
 145         .hangup                 = ssl_hangup,
 146 #endif
 147 };
 148
 149 /* Changed by ssl_init and referenced by ssl_exit, which are both serialized
 150  * by being an initcall and exitcall, respectively.
 151  */
 152 static int ssl_init_done = 0;
 153
 154 static void ssl_console_write(struct console *c, const char *string,
 155                               unsigned len)
 156 {
 157         struct line *line = &serial_lines[c->index];
 158         unsigned long flags;
 159
 160         spin_lock_irqsave(&line->lock, flags);
 161         console_write_chan(&line->chan_list, string, len);
 162         spin_unlock_irqrestore(&line->lock, flags);
 163 }
 164
 165 static struct tty_driver *ssl_console_device(struct console *c, int *index)
 166 {
 167         *index = c->index;
 168         return ssl_driver;
 169 }
 170
 171 static int ssl_console_setup(struct console *co, char *options)
 172 {
 173         struct line *line = &serial_lines[co->index];
 174
 175         return console_open_chan(line, co);
 176 }
 177
 178 /* No locking for register_console call - relies on single-threaded initcalls */
 179 static struct console ssl_cons = {
 180         .name           = "ttyS",
 181         .write          = ssl_console_write,
 182         .device         = ssl_console_device,
 183         .setup          = ssl_console_setup,
 184         .flags          = CON_PRINTBUFFER|CON_ANYTIME,
 185         .index          = -1,
 186 };
 187
 188 static int ssl_init(void)
 189 {
 190         char *new_title;
 191
 192         printk(KERN_INFO "Initializing software serial port version %d\n",
 193                ssl_version);
 194         ssl_driver = register_lines(&driver, &ssl_ops, serial_lines,
 195                                     ARRAY_SIZE(serial_lines));
 196
 197         new_title = add_xterm_umid(opts.xterm_title);
 198         if (new_title != NULL)
 199                 opts.xterm_title = new_title;
 200
 201         lines_init(serial_lines, ARRAY_SIZE(serial_lines), &opts);
 202
 203         ssl_init_done = 1;
 204         register_console(&ssl_cons);
 205         return 0;
 206 }
 207 late_initcall(ssl_init);
 208
 209 static void ssl_exit(void)
 210 {
 211         if (!ssl_init_done)
 212                 return;
 213         close_lines(serial_lines, ARRAY_SIZE(serial_lines));
 214 }
 215 __uml_exitcall(ssl_exit);
 216
 217 static int ssl_chan_setup(char *str)
 218 {
 219         char *error;
 220         int ret;
 221
 222         ret = line_setup(serial_lines, ARRAY_SIZE(serial_lines), str, &error);
 223         if(ret < 0)
 224                 printk(KERN_ERR "Failed to set up serial line with "
 225                        "configuration string \"%s\" : %s\n", str, error);
 226
 227         return 1;
 228 }
 229
 230 __setup("ssl", ssl_chan_setup);
 231 __channel_help(ssl_chan_setup, "ssl");