arch/m68k/emu/nfcon.c

   1 /*
   2  * ARAnyM console driver
   3  *
   4  * This file is subject to the terms and conditions of the GNU General Public
   5  * License.  See the file COPYING in the main directory of this archive
   6  * for more details.
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/init.h>
  11 #include <linux/console.h>
  12 #include <linux/tty.h>
  13 #include <linux/tty_driver.h>
  14 #include <linux/tty_flip.h>
  15 #include <linux/slab.h>
  16 #include <linux/err.h>
  17 #include <linux/uaccess.h>
  18
  19 #include <asm/natfeat.h>
  20
  21 static int stderr_id;
  22 static struct tty_driver *nfcon_tty_driver;
  23
  24 static void nfputs(const char *str, unsigned int count)
  25 {
  26         char buf[68];
  27
  28         buf[64] = 0;
  29         while (count > 64) {
  30                 memcpy(buf, str, 64);
  31                 nf_call(stderr_id, buf);
  32                 str += 64;
  33                 count -= 64;
  34         }
  35         memcpy(buf, str, count);
  36         buf[count] = 0;
  37         nf_call(stderr_id, buf);
  38 }
  39
  40 static void nfcon_write(struct console *con, const char *str,
  41                         unsigned int count)
  42 {
  43         nfputs(str, count);
  44 }
  45
  46 static struct tty_driver *nfcon_device(struct console *con, int *index)
  47 {
  48         *index = 0;
  49         return (con->flags & CON_ENABLED) ? nfcon_tty_driver : NULL;
  50 }
  51
  52 static struct console nf_console = {
  53         .name   = "nfcon",
  54         .write  = nfcon_write,
  55         .device = nfcon_device,
  56         .flags  = CON_PRINTBUFFER,
  57         .index  = -1,
  58 };
  59
  60
  61 static int nfcon_tty_open(struct tty_struct *tty, struct file *filp)
  62 {
  63         return 0;
  64 }
  65
  66 static void nfcon_tty_close(struct tty_struct *tty, struct file *filp)
  67 {
  68 }
  69
  70 static int nfcon_tty_write(struct tty_struct *tty, const unsigned char *buf,
  71                            int count)
  72 {
  73         nfputs(buf, count);
  74         return count;
  75 }
  76
  77 static int nfcon_tty_put_char(struct tty_struct *tty, unsigned char ch)
  78 {
  79         char temp[2] = { ch, 0 };
  80
  81         nf_call(stderr_id, temp);
  82         return 1;
  83 }
  84
  85 static int nfcon_tty_write_room(struct tty_struct *tty)
  86 {
  87         return 64;
  88 }
  89
  90 static const struct tty_operations nfcon_tty_ops = {
  91         .open           = nfcon_tty_open,
  92         .close          = nfcon_tty_close,
  93         .write          = nfcon_tty_write,
  94         .put_char       = nfcon_tty_put_char,
  95         .write_room     = nfcon_tty_write_room,
  96 };
  97
  98 #ifndef MODULE
  99
 100 static int __init nf_debug_setup(char *arg)
 101 {
 102         if (strcmp(arg, "nfcon"))
 103                 return 0;
 104
 105         stderr_id = nf_get_id("NF_STDERR");
 106         if (stderr_id) {
 107                 nf_console.flags |= CON_ENABLED;
 108                 register_console(&nf_console);
 109         }
 110
 111         return 0;
 112 }
 113
 114 early_param("debug", nf_debug_setup);
 115
 116 #endif /* !MODULE */
 117
 118 static int __init nfcon_init(void)
 119 {
 120         int res;
 121
 122         stderr_id = nf_get_id("NF_STDERR");
 123         if (!stderr_id)
 124                 return -ENODEV;
 125
 126         nfcon_tty_driver = alloc_tty_driver(1);
 127         if (!nfcon_tty_driver)
 128                 return -ENOMEM;
 129
 130         nfcon_tty_driver->owner = THIS_MODULE;
 131         nfcon_tty_driver->driver_name = "nfcon";
 132         nfcon_tty_driver->name = "nfcon";
 133         nfcon_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM;
 134         nfcon_tty_driver->subtype = SYSTEM_TYPE_TTY;
 135         nfcon_tty_driver->init_termios = tty_std_termios;
 136         nfcon_tty_driver->flags = TTY_DRIVER_REAL_RAW;
 137
 138         tty_set_operations(nfcon_tty_driver, &nfcon_tty_ops);
 139         res = tty_register_driver(nfcon_tty_driver);
 140         if (res) {
 141                 pr_err("failed to register nfcon tty driver\n");
 142                 put_tty_driver(nfcon_tty_driver);
 143                 return res;
 144         }
 145
 146         if (!(nf_console.flags & CON_ENABLED))
 147                 register_console(&nf_console);
 148
 149         return 0;
 150 }
 151
 152 static void __exit nfcon_exit(void)
 153 {
 154         unregister_console(&nf_console);
 155         tty_unregister_driver(nfcon_tty_driver);
 156         put_tty_driver(nfcon_tty_driver);
 157 }
 158
 159 module_init(nfcon_init);
 160 module_exit(nfcon_exit);
 161
 162 MODULE_LICENSE("GPL");