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 | #include <linux/io.h> |
19 | |
20 | #include <asm/natfeat.h> |
21 | |
22 | static int stderr_id; |
23 | static struct tty_port nfcon_tty_port; |
24 | static struct tty_driver *nfcon_tty_driver; |
25 | |
26 | static void nfputs(const u8 *str, size_t count) |
27 | { |
28 | u8 buf[68]; |
29 | unsigned long phys = virt_to_phys(address: 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 | |
43 | static void nfcon_write(struct console *con, const char *str, |
44 | unsigned int count) |
45 | { |
46 | nfputs(str, count); |
47 | } |
48 | |
49 | static struct tty_driver *nfcon_device(struct console *con, int *index) |
50 | { |
51 | *index = 0; |
52 | return console_is_registered(con) ? nfcon_tty_driver : NULL; |
53 | } |
54 | |
55 | static 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 | |
64 | static int nfcon_tty_open(struct tty_struct *tty, struct file *filp) |
65 | { |
66 | return 0; |
67 | } |
68 | |
69 | static void nfcon_tty_close(struct tty_struct *tty, struct file *filp) |
70 | { |
71 | } |
72 | |
73 | static ssize_t nfcon_tty_write(struct tty_struct *tty, const u8 *buf, |
74 | size_t count) |
75 | { |
76 | nfputs(str: buf, count); |
77 | return count; |
78 | } |
79 | |
80 | static int nfcon_tty_put_char(struct tty_struct *tty, u8 ch) |
81 | { |
82 | u8 temp[2] = { ch, 0 }; |
83 | |
84 | nf_call(stderr_id, virt_to_phys(address: temp)); |
85 | return 1; |
86 | } |
87 | |
88 | static unsigned int nfcon_tty_write_room(struct tty_struct *tty) |
89 | { |
90 | return 64; |
91 | } |
92 | |
93 | static 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 | |
103 | static 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 | /* |
111 | * The console will be enabled when debug=nfcon is specified |
112 | * as a kernel parameter. Since this is a non-standard way |
113 | * of enabling consoles, it must be explicitly enabled. |
114 | */ |
115 | nf_console.flags |= CON_ENABLED; |
116 | register_console(&nf_console); |
117 | } |
118 | |
119 | return 0; |
120 | } |
121 | |
122 | early_param("debug" , nf_debug_setup); |
123 | |
124 | #endif /* !MODULE */ |
125 | |
126 | static int __init nfcon_init(void) |
127 | { |
128 | struct tty_driver *driver; |
129 | int res; |
130 | |
131 | stderr_id = nf_get_id("NF_STDERR" ); |
132 | if (!stderr_id) |
133 | return -ENODEV; |
134 | |
135 | driver = tty_alloc_driver(1, TTY_DRIVER_REAL_RAW); |
136 | if (IS_ERR(ptr: driver)) |
137 | return PTR_ERR(ptr: driver); |
138 | |
139 | tty_port_init(port: &nfcon_tty_port); |
140 | |
141 | driver->driver_name = "nfcon" ; |
142 | driver->name = "nfcon" ; |
143 | driver->type = TTY_DRIVER_TYPE_SYSTEM; |
144 | driver->subtype = SYSTEM_TYPE_TTY; |
145 | driver->init_termios = tty_std_termios; |
146 | |
147 | tty_set_operations(driver, op: &nfcon_tty_ops); |
148 | tty_port_link_device(port: &nfcon_tty_port, driver, index: 0); |
149 | res = tty_register_driver(driver); |
150 | if (res) { |
151 | pr_err("failed to register nfcon tty driver\n" ); |
152 | tty_driver_kref_put(driver); |
153 | tty_port_destroy(port: &nfcon_tty_port); |
154 | return res; |
155 | } |
156 | |
157 | nfcon_tty_driver = driver; |
158 | |
159 | if (!console_is_registered(con: &nf_console)) |
160 | register_console(&nf_console); |
161 | |
162 | return 0; |
163 | } |
164 | |
165 | static void __exit nfcon_exit(void) |
166 | { |
167 | unregister_console(&nf_console); |
168 | tty_unregister_driver(driver: nfcon_tty_driver); |
169 | tty_driver_kref_put(driver: nfcon_tty_driver); |
170 | tty_port_destroy(port: &nfcon_tty_port); |
171 | } |
172 | |
173 | module_init(nfcon_init); |
174 | module_exit(nfcon_exit); |
175 | |
176 | MODULE_LICENSE("GPL" ); |
177 | |