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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#include <linux/io.h>
19
20#include <asm/natfeat.h>
21
22static int stderr_id;
23static struct tty_port nfcon_tty_port;
24static struct tty_driver *nfcon_tty_driver;
25
26static void nfputs(const char *str, unsigned int count)
27{
28 char buf[68];
29 unsigned long phys = virt_to_phys(buf);
30
31 buf[64] = 0;
32 while (count > 64) {
33 memcpy(buf, str, 64);
34 nf_call(stderr_id, phys);
35 str += 64;
36 count -= 64;
37 }
38 memcpy(buf, str, count);
39 buf[count] = 0;
40 nf_call(stderr_id, phys);
41}
42
43static void nfcon_write(struct console *con, const char *str,
44 unsigned int count)
45{
46 nfputs(str, count);
47}
48
49static struct tty_driver *nfcon_device(struct console *con, int *index)
50{
51 *index = 0;
52 return (con->flags & CON_ENABLED) ? nfcon_tty_driver : NULL;
53}
54
55static struct console nf_console = {
56 .name = "nfcon",
57 .write = nfcon_write,
58 .device = nfcon_device,
59 .flags = CON_PRINTBUFFER,
60 .index = -1,
61};
62
63
64static int nfcon_tty_open(struct tty_struct *tty, struct file *filp)
65{
66 return 0;
67}
68
69static void nfcon_tty_close(struct tty_struct *tty, struct file *filp)
70{
71}
72
73static int nfcon_tty_write(struct tty_struct *tty, const unsigned char *buf,
74 int count)
75{
76 nfputs(buf, count);
77 return count;
78}
79
80static int nfcon_tty_put_char(struct tty_struct *tty, unsigned char ch)
81{
82 char temp[2] = { ch, 0 };
83
84 nf_call(stderr_id, virt_to_phys(temp));
85 return 1;
86}
87
88static unsigned int nfcon_tty_write_room(struct tty_struct *tty)
89{
90 return 64;
91}
92
93static const struct tty_operations nfcon_tty_ops = {
94 .open = nfcon_tty_open,
95 .close = nfcon_tty_close,
96 .write = nfcon_tty_write,
97 .put_char = nfcon_tty_put_char,
98 .write_room = nfcon_tty_write_room,
99};
100
101#ifndef MODULE
102
103static int __init nf_debug_setup(char *arg)
104{
105 if (strcmp(arg, "nfcon"))
106 return 0;
107
108 stderr_id = nf_get_id("NF_STDERR");
109 if (stderr_id) {
110 nf_console.flags |= CON_ENABLED;
111 register_console(&nf_console);
112 }
113
114 return 0;
115}
116
117early_param("debug", nf_debug_setup);
118
119#endif
120
121static int __init nfcon_init(void)
122{
123 struct tty_driver *driver;
124 int res;
125
126 stderr_id = nf_get_id("NF_STDERR");
127 if (!stderr_id)
128 return -ENODEV;
129
130 driver = tty_alloc_driver(1, TTY_DRIVER_REAL_RAW);
131 if (IS_ERR(driver))
132 return PTR_ERR(driver);
133
134 tty_port_init(&nfcon_tty_port);
135
136 driver->driver_name = "nfcon";
137 driver->name = "nfcon";
138 driver->type = TTY_DRIVER_TYPE_SYSTEM;
139 driver->subtype = SYSTEM_TYPE_TTY;
140 driver->init_termios = tty_std_termios;
141
142 tty_set_operations(driver, &nfcon_tty_ops);
143 tty_port_link_device(&nfcon_tty_port, driver, 0);
144 res = tty_register_driver(driver);
145 if (res) {
146 pr_err("failed to register nfcon tty driver\n");
147 tty_driver_kref_put(driver);
148 tty_port_destroy(&nfcon_tty_port);
149 return res;
150 }
151
152 nfcon_tty_driver = driver;
153
154 if (!(nf_console.flags & CON_ENABLED))
155 register_console(&nf_console);
156
157 return 0;
158}
159
160static void __exit nfcon_exit(void)
161{
162 unregister_console(&nf_console);
163 tty_unregister_driver(nfcon_tty_driver);
164 tty_driver_kref_put(nfcon_tty_driver);
165 tty_port_destroy(&nfcon_tty_port);
166}
167
168module_init(nfcon_init);
169module_exit(nfcon_exit);
170
171MODULE_LICENSE("GPL");
172
