2 * arch/xtensa/platforms/iss/console.c
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
8 * Copyright (C) 2001-2005 Tensilica Inc.
9 * Authors Christian Zankel, Joe Taylor
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>
18 #include <linux/major.h>
19 #include <linux/param.h>
20 #include <linux/seq_file.h>
21 #include <linux/serial.h>
22 #include <linux/serialP.h>
24 #include <asm/uaccess.h>
27 #include <platform/simcall.h>
29 #include <linux/tty.h>
30 #include <linux/tty_flip.h>
33 #define _INLINE_ inline
36 #define SERIAL_MAX_NUM_LINES 1
37 #define SERIAL_TIMER_VALUE (20 * HZ)
39 static struct tty_driver *serial_driver;
40 static struct tty_port serial_port;
41 static struct timer_list serial_timer;
43 static DEFINE_SPINLOCK(timer_lock);
47 static int __simc (int a, int b, int c, int d, int e, int f) __attribute__((__noinline__));
48 static int __simc (int a, int b, int c, int d, int e, int f)
51 __asm__ __volatile__ ("simcall\n"
53 "mov %1, a3\n" : "=a" (ret), "=a" (errno)
58 static char *serial_version = "0.1";
59 static char *serial_name = "ISS serial driver";
62 * This routine is called whenever a serial port is opened. It
63 * enables interrupts for a serial port, linking in its async structure into
64 * the IRQ chain. It also performs the serial-specific
65 * initialization for the tty structure.
68 static void rs_poll(unsigned long);
70 static int rs_open(struct tty_struct *tty, struct file * filp)
72 tty->port = &serial_port;
73 spin_lock(&timer_lock);
74 if (tty->count == 1) {
75 setup_timer(&serial_timer, rs_poll, (unsigned long)tty);
76 mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE);
78 spin_unlock(&timer_lock);
85 * ------------------------------------------------------------
88 * This routine is called when the serial port gets closed. First, we
89 * wait for the last remaining data to be sent. Then, we unlink its
90 * async structure from the interrupt chain if necessary, and we free
91 * that IRQ if nothing is left in the chain.
92 * ------------------------------------------------------------
94 static void rs_close(struct tty_struct *tty, struct file * filp)
96 spin_lock_bh(&timer_lock);
98 del_timer_sync(&serial_timer);
99 spin_unlock_bh(&timer_lock);
103 static int rs_write(struct tty_struct * tty,
104 const unsigned char *buf, int count)
106 /* see drivers/char/serialX.c to reference original version */
108 __simc (SYS_write, 1, (unsigned long)buf, count, 0, 0);
112 static void rs_poll(unsigned long priv)
114 struct tty_struct* tty = (struct tty_struct*) priv;
116 struct timeval tv = { .tv_sec = 0, .tv_usec = 0 };
120 spin_lock(&timer_lock);
122 while (__simc(SYS_select_one, 0, XTISS_SELECT_ONE_READ, (int)&tv,0,0)){
123 __simc (SYS_read, 0, (unsigned long)&c, 1, 0, 0);
124 tty_insert_flip_char(tty, c, TTY_NORMAL);
129 tty_flip_buffer_push(tty);
132 mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE);
133 spin_unlock(&timer_lock);
137 static int rs_put_char(struct tty_struct *tty, unsigned char ch)
142 buf[1] = '\0'; /* Is this NULL necessary? */
143 __simc (SYS_write, 1, (unsigned long) buf, 1, 0, 0);
147 static void rs_flush_chars(struct tty_struct *tty)
151 static int rs_write_room(struct tty_struct *tty)
153 /* Let's say iss can always accept 2K characters.. */
157 static int rs_chars_in_buffer(struct tty_struct *tty)
159 /* the iss doesn't buffer characters */
163 static void rs_hangup(struct tty_struct *tty)
165 /* Stub, once again.. */
168 static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
170 /* Stub, once again.. */
173 static int rs_proc_show(struct seq_file *m, void *v)
175 seq_printf(m, "serinfo:1.0 driver:%s\n", serial_version);
179 static int rs_proc_open(struct inode *inode, struct file *file)
181 return single_open(file, rs_proc_show, NULL);
184 static const struct file_operations rs_proc_fops = {
185 .owner = THIS_MODULE,
186 .open = rs_proc_open,
189 .release = single_release,
192 static const struct tty_operations serial_ops = {
196 .put_char = rs_put_char,
197 .flush_chars = rs_flush_chars,
198 .write_room = rs_write_room,
199 .chars_in_buffer = rs_chars_in_buffer,
201 .wait_until_sent = rs_wait_until_sent,
202 .proc_fops = &rs_proc_fops,
205 int __init rs_init(void)
207 tty_port_init(&serial_port);
209 serial_driver = alloc_tty_driver(SERIAL_MAX_NUM_LINES);
211 printk ("%s %s\n", serial_name, serial_version);
213 /* Initialize the tty_driver structure */
215 serial_driver->driver_name = "iss_serial";
216 serial_driver->name = "ttyS";
217 serial_driver->major = TTY_MAJOR;
218 serial_driver->minor_start = 64;
219 serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
220 serial_driver->subtype = SERIAL_TYPE_NORMAL;
221 serial_driver->init_termios = tty_std_termios;
222 serial_driver->init_termios.c_cflag =
223 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
224 serial_driver->flags = TTY_DRIVER_REAL_RAW;
226 tty_set_operations(serial_driver, &serial_ops);
228 if (tty_register_driver(serial_driver))
229 panic("Couldn't register serial driver\n");
234 static __exit void rs_exit(void)
238 if ((error = tty_unregister_driver(serial_driver)))
239 printk("ISS_SERIAL: failed to unregister serial driver (%d)\n",
241 put_tty_driver(serial_driver);
245 /* We use `late_initcall' instead of just `__initcall' as a workaround for
246 * the fact that (1) simcons_tty_init can't be called before tty_init,
247 * (2) tty_init is called via `module_init', (3) if statically linked,
248 * module_init == device_init, and (4) there's no ordering of init lists.
249 * We can do this easily because simcons is always statically linked, but
250 * other tty drivers that depend on tty_init and which must use
251 * `module_init' to declare their init routines are likely to be broken.
254 late_initcall(rs_init);
257 #ifdef CONFIG_SERIAL_CONSOLE
259 static void iss_console_write(struct console *co, const char *s, unsigned count)
263 if (s != 0 && *s != 0)
264 __simc (SYS_write, 1, (unsigned long)s,
265 count < len ? count : len,0,0);
268 static struct tty_driver* iss_console_device(struct console *c, int *index)
271 return serial_driver;
275 static struct console sercons = {
277 .write = iss_console_write,
278 .device = iss_console_device,
279 .flags = CON_PRINTBUFFER,
283 static int __init iss_console_init(void)
285 register_console(&sercons);
289 console_initcall(iss_console_init);
291 #endif /* CONFIG_SERIAL_CONSOLE */