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 timer_list serial_timer;
42 static DEFINE_SPINLOCK(timer_lock);
46 static int __simc (int a, int b, int c, int d, int e, int f) __attribute__((__noinline__));
47 static int __simc (int a, int b, int c, int d, int e, int f)
50 __asm__ __volatile__ ("simcall\n"
52 "mov %1, a3\n" : "=a" (ret), "=a" (errno)
57 static char *serial_version = "0.1";
58 static char *serial_name = "ISS serial driver";
61 * This routine is called whenever a serial port is opened. It
62 * enables interrupts for a serial port, linking in its async structure into
63 * the IRQ chain. It also performs the serial-specific
64 * initialization for the tty structure.
67 static void rs_poll(unsigned long);
69 static int rs_open(struct tty_struct *tty, struct file * filp)
71 spin_lock(&timer_lock);
72 if (tty->count == 1) {
73 setup_timer(&serial_timer, rs_poll, (unsigned long)tty);
74 mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE);
76 spin_unlock(&timer_lock);
83 * ------------------------------------------------------------
86 * This routine is called when the serial port gets closed. First, we
87 * wait for the last remaining data to be sent. Then, we unlink its
88 * async structure from the interrupt chain if necessary, and we free
89 * that IRQ if nothing is left in the chain.
90 * ------------------------------------------------------------
92 static void rs_close(struct tty_struct *tty, struct file * filp)
94 spin_lock_bh(&timer_lock);
96 del_timer_sync(&serial_timer);
97 spin_unlock_bh(&timer_lock);
101 static int rs_write(struct tty_struct * tty,
102 const unsigned char *buf, int count)
104 /* see drivers/char/serialX.c to reference original version */
106 __simc (SYS_write, 1, (unsigned long)buf, count, 0, 0);
110 static void rs_poll(unsigned long priv)
112 struct tty_struct* tty = (struct tty_struct*) priv;
114 struct timeval tv = { .tv_sec = 0, .tv_usec = 0 };
118 spin_lock(&timer_lock);
120 while (__simc(SYS_select_one, 0, XTISS_SELECT_ONE_READ, (int)&tv,0,0)){
121 __simc (SYS_read, 0, (unsigned long)&c, 1, 0, 0);
122 tty_insert_flip_char(tty, c, TTY_NORMAL);
127 tty_flip_buffer_push(tty);
130 mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE);
131 spin_unlock(&timer_lock);
135 static int rs_put_char(struct tty_struct *tty, unsigned char ch)
140 buf[1] = '\0'; /* Is this NULL necessary? */
141 __simc (SYS_write, 1, (unsigned long) buf, 1, 0, 0);
145 static void rs_flush_chars(struct tty_struct *tty)
149 static int rs_write_room(struct tty_struct *tty)
151 /* Let's say iss can always accept 2K characters.. */
155 static int rs_chars_in_buffer(struct tty_struct *tty)
157 /* the iss doesn't buffer characters */
161 static void rs_hangup(struct tty_struct *tty)
163 /* Stub, once again.. */
166 static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
168 /* Stub, once again.. */
171 static int rs_proc_show(struct seq_file *m, void *v)
173 seq_printf(m, "serinfo:1.0 driver:%s\n", serial_version);
177 static int rs_proc_open(struct inode *inode, struct file *file)
179 return single_open(file, rs_proc_show, NULL);
182 static const struct file_operations rs_proc_fops = {
183 .owner = THIS_MODULE,
184 .open = rs_proc_open,
187 .release = single_release,
190 static const struct tty_operations serial_ops = {
194 .put_char = rs_put_char,
195 .flush_chars = rs_flush_chars,
196 .write_room = rs_write_room,
197 .chars_in_buffer = rs_chars_in_buffer,
199 .wait_until_sent = rs_wait_until_sent,
200 .proc_fops = &rs_proc_fops,
203 int __init rs_init(void)
205 serial_driver = alloc_tty_driver(SERIAL_MAX_NUM_LINES);
207 printk ("%s %s\n", serial_name, serial_version);
209 /* Initialize the tty_driver structure */
211 serial_driver->driver_name = "iss_serial";
212 serial_driver->name = "ttyS";
213 serial_driver->major = TTY_MAJOR;
214 serial_driver->minor_start = 64;
215 serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
216 serial_driver->subtype = SERIAL_TYPE_NORMAL;
217 serial_driver->init_termios = tty_std_termios;
218 serial_driver->init_termios.c_cflag =
219 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
220 serial_driver->flags = TTY_DRIVER_REAL_RAW;
222 tty_set_operations(serial_driver, &serial_ops);
224 if (tty_register_driver(serial_driver))
225 panic("Couldn't register serial driver\n");
230 static __exit void rs_exit(void)
234 if ((error = tty_unregister_driver(serial_driver)))
235 printk("ISS_SERIAL: failed to unregister serial driver (%d)\n",
237 put_tty_driver(serial_driver);
241 /* We use `late_initcall' instead of just `__initcall' as a workaround for
242 * the fact that (1) simcons_tty_init can't be called before tty_init,
243 * (2) tty_init is called via `module_init', (3) if statically linked,
244 * module_init == device_init, and (4) there's no ordering of init lists.
245 * We can do this easily because simcons is always statically linked, but
246 * other tty drivers that depend on tty_init and which must use
247 * `module_init' to declare their init routines are likely to be broken.
250 late_initcall(rs_init);
253 #ifdef CONFIG_SERIAL_CONSOLE
255 static void iss_console_write(struct console *co, const char *s, unsigned count)
259 if (s != 0 && *s != 0)
260 __simc (SYS_write, 1, (unsigned long)s,
261 count < len ? count : len,0,0);
264 static struct tty_driver* iss_console_device(struct console *c, int *index)
267 return serial_driver;
271 static struct console sercons = {
273 .write = iss_console_write,
274 .device = iss_console_device,
275 .flags = CON_PRINTBUFFER,
279 static int __init iss_console_init(void)
281 register_console(&sercons);
285 console_initcall(iss_console_init);
287 #endif /* CONFIG_SERIAL_CONSOLE */