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-rw-r--r--arch/xtensa/platforms/iss/console.c296
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diff --git a/arch/xtensa/platforms/iss/console.c b/arch/xtensa/platforms/iss/console.c
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1/*
2 * arch/xtensa/platform-iss/console.c
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 * Copyright (C) 2001-2005 Tensilica Inc.
9 * Authors Christian Zankel, Joe Taylor
10 */
11
12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/sched.h>
15#include <linux/console.h>
16#include <linux/init.h>
17#include <linux/slab.h>
18#include <linux/mm.h>
19#include <linux/major.h>
20#include <linux/param.h>
21#include <linux/serial.h>
22#include <linux/serialP.h>
23
24#include <asm/uaccess.h>
25#include <asm/irq.h>
26
27#include <asm/platform/simcall.h>
28
29#include <linux/tty.h>
30#include <linux/tty_flip.h>
31
32#ifdef SERIAL_INLINE
33#define _INLINE_ inline
34#endif
35
36#define SERIAL_MAX_NUM_LINES 1
37#define SERIAL_TIMER_VALUE (20 * HZ)
38
39static struct tty_driver *serial_driver;
40static struct timer_list serial_timer;
41
42static DEFINE_SPINLOCK(timer_lock);
43
44int errno;
45
46static int __simc (int a, int b, int c, int d, int e, int f)
47{
48 int ret;
49 __asm__ __volatile__ ("simcall\n"
50 "mov %0, a2\n"
51 "mov %1, a3\n" : "=a" (ret), "=a" (errno)
52 : : "a2", "a3");
53 return ret;
54}
55
56static char *serial_version = "0.1";
57static char *serial_name = "ISS serial driver";
58
59/*
60 * This routine is called whenever a serial port is opened. It
61 * enables interrupts for a serial port, linking in its async structure into
62 * the IRQ chain. It also performs the serial-specific
63 * initialization for the tty structure.
64 */
65
66static void rs_poll(unsigned long);
67
68static int rs_open(struct tty_struct *tty, struct file * filp)
69{
70 int line = tty->index;
71
72 if ((line < 0) || (line >= SERIAL_MAX_NUM_LINES))
73 return -ENODEV;
74
75 spin_lock(&timer_lock);
76
77 if (tty->count == 1) {
78 init_timer(&serial_timer);
79 serial_timer.data = (unsigned long) tty;
80 serial_timer.function = rs_poll;
81 mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE);
82 }
83 spin_unlock(&timer_lock);
84
85 return 0;
86}
87
88
89/*
90 * ------------------------------------------------------------
91 * iss_serial_close()
92 *
93 * This routine is called when the serial port gets closed. First, we
94 * wait for the last remaining data to be sent. Then, we unlink its
95 * async structure from the interrupt chain if necessary, and we free
96 * that IRQ if nothing is left in the chain.
97 * ------------------------------------------------------------
98 */
99static void rs_close(struct tty_struct *tty, struct file * filp)
100{
101 spin_lock(&timer_lock);
102 if (tty->count == 1)
103 del_timer_sync(&serial_timer);
104 spin_unlock(&timer_lock);
105}
106
107
108static int rs_write(struct tty_struct * tty,
109 const unsigned char *buf, int count)
110{
111 /* see drivers/char/serialX.c to reference original version */
112
113 __simc (SYS_write, 1, (unsigned long)buf, count, 0, 0);
114 return count;
115}
116
117static void rs_poll(unsigned long priv)
118{
119 struct tty_struct* tty = (struct tty_struct*) priv;
120
121 struct timeval tv = { .tv_sec = 0, .tv_usec = 0 };
122 int i = 0;
123 unsigned char c;
124
125 spin_lock(&timer_lock);
126
127 while (__simc(SYS_select_one, 0, XTISS_SELECT_ONE_READ, (int)&tv,0,0)){
128 __simc (SYS_read, 0, (unsigned long)&c, 1, 0, 0);
129 tty_insert_flip_char(tty, c, TTY_NORMAL);
130 i++;
131 }
132
133 if (i)
134 tty_flip_buffer_push(tty);
135
136
137 mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE);
138 spin_unlock(&timer_lock);
139}
140
141
142static void rs_put_char(struct tty_struct *tty, unsigned char ch)
143{
144 char buf[2];
145
146 if (!tty)
147 return;
148
149 buf[0] = ch;
150 buf[1] = '\0'; /* Is this NULL necessary? */
151 __simc (SYS_write, 1, (unsigned long) buf, 1, 0, 0);
152}
153
154static void rs_flush_chars(struct tty_struct *tty)
155{
156}
157
158static int rs_write_room(struct tty_struct *tty)
159{
160 /* Let's say iss can always accept 2K characters.. */
161 return 2 * 1024;
162}
163
164static int rs_chars_in_buffer(struct tty_struct *tty)
165{
166 /* the iss doesn't buffer characters */
167 return 0;
168}
169
170static void rs_hangup(struct tty_struct *tty)
171{
172 /* Stub, once again.. */
173}
174
175static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
176{
177 /* Stub, once again.. */
178}
179
180static int rs_read_proc(char *page, char **start, off_t off, int count,
181 int *eof, void *data)
182{
183 int len = 0;
184 off_t begin = 0;
185
186 len += sprintf(page, "serinfo:1.0 driver:%s\n", serial_version);
187 *eof = 1;
188
189 if (off >= len + begin)
190 return 0;
191
192 *start = page + (off - begin);
193 return ((count < begin + len - off) ? count : begin + len - off);
194}
195
196
197static struct tty_operations serial_ops = {
198 .open = rs_open,
199 .close = rs_close,
200 .write = rs_write,
201 .put_char = rs_put_char,
202 .flush_chars = rs_flush_chars,
203 .write_room = rs_write_room,
204 .chars_in_buffer = rs_chars_in_buffer,
205 .hangup = rs_hangup,
206 .wait_until_sent = rs_wait_until_sent,
207 .read_proc = rs_read_proc
208};
209
210int __init rs_init(void)
211{
212 serial_driver = alloc_tty_driver(1);
213
214 printk ("%s %s\n", serial_name, serial_version);
215
216 /* Initialize the tty_driver structure */
217
218 serial_driver->owner = THIS_MODULE;
219 serial_driver->driver_name = "iss_serial";
220 serial_driver->name = "ttyS";
221 serial_driver->major = TTY_MAJOR;
222 serial_driver->minor_start = 64;
223 serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
224 serial_driver->subtype = SERIAL_TYPE_NORMAL;
225 serial_driver->init_termios = tty_std_termios;
226 serial_driver->init_termios.c_cflag =
227 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
228 serial_driver->flags = TTY_DRIVER_REAL_RAW;
229
230 tty_set_operations(serial_driver, &serial_ops);
231
232 if (tty_register_driver(serial_driver))
233 panic("Couldn't register serial driver\n");
234 return 0;
235}
236
237
238static __exit void rs_exit(void)
239{
240 int error;
241
242 if ((error = tty_unregister_driver(serial_driver)))
243 printk("ISS_SERIAL: failed to unregister serial driver (%d)\n",
244 error);
245 put_tty_driver(serial_driver);
246}
247
248
249/* We use `late_initcall' instead of just `__initcall' as a workaround for
250 * the fact that (1) simcons_tty_init can't be called before tty_init,
251 * (2) tty_init is called via `module_init', (3) if statically linked,
252 * module_init == device_init, and (4) there's no ordering of init lists.
253 * We can do this easily because simcons is always statically linked, but
254 * other tty drivers that depend on tty_init and which must use
255 * `module_init' to declare their init routines are likely to be broken.
256 */
257
258late_initcall(rs_init);
259
260
261#ifdef CONFIG_SERIAL_CONSOLE
262
263static void iss_console_write(struct console *co, const char *s, unsigned count)
264{
265 int len = strlen(s);
266
267 if (s != 0 && *s != 0)
268 __simc (SYS_write, 1, (unsigned long)s,
269 count < len ? count : len,0,0);
270}
271
272static struct tty_driver* iss_console_device(struct console *c, int *index)
273{
274 *index = c->index;
275 return serial_driver;
276}
277
278
279static struct console sercons = {
280 .name = "ttyS",
281 .write = iss_console_write,
282 .device = iss_console_device,
283 .flags = CON_PRINTBUFFER,
284 .index = -1
285};
286
287static int __init iss_console_init(void)
288{
289 register_console(&sercons);
290 return 0;
291}
292
293console_initcall(iss_console_init);
294
295#endif /* CONFIG_SERIAL_CONSOLE */
296