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
 21static int stderr_id;
 22static struct tty_driver *nfcon_tty_driver;
 23
 24static 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
 40static void nfcon_write(struct console *con, const char *str,
 41			unsigned int count)
 42{
 43	nfputs(str, count);
 44}
 45
 46static 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
 52static 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
 61static int nfcon_tty_open(struct tty_struct *tty, struct file *filp)
 62{
 63	return 0;
 64}
 65
 66static void nfcon_tty_close(struct tty_struct *tty, struct file *filp)
 67{
 68}
 69
 70static 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
 77static 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
 85static int nfcon_tty_write_room(struct tty_struct *tty)
 86{
 87	return 64;
 88}
 89
 90static 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
100static 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
114early_param("debug", nf_debug_setup);
115
116#endif /* !MODULE */
117
118static 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->driver_name = "nfcon";
131	nfcon_tty_driver->name = "nfcon";
132	nfcon_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM;
133	nfcon_tty_driver->subtype = SYSTEM_TYPE_TTY;
134	nfcon_tty_driver->init_termios = tty_std_termios;
135	nfcon_tty_driver->flags = TTY_DRIVER_REAL_RAW;
136
137	tty_set_operations(nfcon_tty_driver, &nfcon_tty_ops);
138	res = tty_register_driver(nfcon_tty_driver);
139	if (res) {
140		pr_err("failed to register nfcon tty driver\n");
141		put_tty_driver(nfcon_tty_driver);
142		return res;
143	}
144
145	if (!(nf_console.flags & CON_ENABLED))
146		register_console(&nf_console);
147
148	return 0;
149}
150
151static void __exit nfcon_exit(void)
152{
153	unregister_console(&nf_console);
154	tty_unregister_driver(nfcon_tty_driver);
155	put_tty_driver(nfcon_tty_driver);
156}
157
158module_init(nfcon_init);
159module_exit(nfcon_exit);
160
161MODULE_LICENSE("GPL");