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>
17 #include <linux/slab.h>
19 #include <linux/major.h>
20 #include <linux/param.h>
21 #include <linux/seq_file.h>
22 #include <linux/serial.h>
23 #include <linux/serialP.h>
25 #include <asm/uaccess.h>
28 #include <platform/simcall.h>
30 #include <linux/tty.h>
31 #include <linux/tty_flip.h>
34 #define _INLINE_ inline
37 #define SERIAL_MAX_NUM_LINES 1
38 #define SERIAL_TIMER_VALUE (20 * HZ)
40 static struct tty_driver
*serial_driver
;
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 int line
= tty
->index
;
74 if ((line
< 0) || (line
>= SERIAL_MAX_NUM_LINES
))
77 spin_lock(&timer_lock
);
79 if (tty
->count
== 1) {
80 init_timer(&serial_timer
);
81 serial_timer
.data
= (unsigned long) tty
;
82 serial_timer
.function
= rs_poll
;
83 mod_timer(&serial_timer
, jiffies
+ SERIAL_TIMER_VALUE
);
85 spin_unlock(&timer_lock
);
92 * ------------------------------------------------------------
95 * This routine is called when the serial port gets closed. First, we
96 * wait for the last remaining data to be sent. Then, we unlink its
97 * async structure from the interrupt chain if necessary, and we free
98 * that IRQ if nothing is left in the chain.
99 * ------------------------------------------------------------
101 static void rs_close(struct tty_struct
*tty
, struct file
* filp
)
103 spin_lock(&timer_lock
);
105 del_timer_sync(&serial_timer
);
106 spin_unlock(&timer_lock
);
110 static int rs_write(struct tty_struct
* tty
,
111 const unsigned char *buf
, int count
)
113 /* see drivers/char/serialX.c to reference original version */
115 __simc (SYS_write
, 1, (unsigned long)buf
, count
, 0, 0);
119 static void rs_poll(unsigned long priv
)
121 struct tty_struct
* tty
= (struct tty_struct
*) priv
;
123 struct timeval tv
= { .tv_sec
= 0, .tv_usec
= 0 };
127 spin_lock(&timer_lock
);
129 while (__simc(SYS_select_one
, 0, XTISS_SELECT_ONE_READ
, (int)&tv
,0,0)){
130 __simc (SYS_read
, 0, (unsigned long)&c
, 1, 0, 0);
131 tty_insert_flip_char(tty
, c
, TTY_NORMAL
);
136 tty_flip_buffer_push(tty
);
139 mod_timer(&serial_timer
, jiffies
+ SERIAL_TIMER_VALUE
);
140 spin_unlock(&timer_lock
);
144 static int rs_put_char(struct tty_struct
*tty
, unsigned char ch
)
149 buf
[1] = '\0'; /* Is this NULL necessary? */
150 __simc (SYS_write
, 1, (unsigned long) buf
, 1, 0, 0);
154 static void rs_flush_chars(struct tty_struct
*tty
)
158 static int rs_write_room(struct tty_struct
*tty
)
160 /* Let's say iss can always accept 2K characters.. */
164 static int rs_chars_in_buffer(struct tty_struct
*tty
)
166 /* the iss doesn't buffer characters */
170 static void rs_hangup(struct tty_struct
*tty
)
172 /* Stub, once again.. */
175 static void rs_wait_until_sent(struct tty_struct
*tty
, int timeout
)
177 /* Stub, once again.. */
180 static int rs_proc_show(struct seq_file
*m
, void *v
)
182 seq_printf(m
, "serinfo:1.0 driver:%s\n", serial_version
);
186 static int rs_proc_open(struct inode
*inode
, struct file
*file
)
188 return single_open(file
, rs_proc_show
, NULL
);
191 static const struct file_operations rs_proc_fops
= {
192 .owner
= THIS_MODULE
,
193 .open
= rs_proc_open
,
196 .release
= single_release
,
199 static const struct tty_operations serial_ops
= {
203 .put_char
= rs_put_char
,
204 .flush_chars
= rs_flush_chars
,
205 .write_room
= rs_write_room
,
206 .chars_in_buffer
= rs_chars_in_buffer
,
208 .wait_until_sent
= rs_wait_until_sent
,
209 .proc_fops
= &rs_proc_fops
,
212 int __init
rs_init(void)
214 serial_driver
= alloc_tty_driver(1);
216 printk ("%s %s\n", serial_name
, serial_version
);
218 /* Initialize the tty_driver structure */
220 serial_driver
->owner
= THIS_MODULE
;
221 serial_driver
->driver_name
= "iss_serial";
222 serial_driver
->name
= "ttyS";
223 serial_driver
->major
= TTY_MAJOR
;
224 serial_driver
->minor_start
= 64;
225 serial_driver
->type
= TTY_DRIVER_TYPE_SERIAL
;
226 serial_driver
->subtype
= SERIAL_TYPE_NORMAL
;
227 serial_driver
->init_termios
= tty_std_termios
;
228 serial_driver
->init_termios
.c_cflag
=
229 B9600
| CS8
| CREAD
| HUPCL
| CLOCAL
;
230 serial_driver
->flags
= TTY_DRIVER_REAL_RAW
;
232 tty_set_operations(serial_driver
, &serial_ops
);
234 if (tty_register_driver(serial_driver
))
235 panic("Couldn't register serial driver\n");
240 static __exit
void rs_exit(void)
244 if ((error
= tty_unregister_driver(serial_driver
)))
245 printk("ISS_SERIAL: failed to unregister serial driver (%d)\n",
247 put_tty_driver(serial_driver
);
251 /* We use `late_initcall' instead of just `__initcall' as a workaround for
252 * the fact that (1) simcons_tty_init can't be called before tty_init,
253 * (2) tty_init is called via `module_init', (3) if statically linked,
254 * module_init == device_init, and (4) there's no ordering of init lists.
255 * We can do this easily because simcons is always statically linked, but
256 * other tty drivers that depend on tty_init and which must use
257 * `module_init' to declare their init routines are likely to be broken.
260 late_initcall(rs_init
);
263 #ifdef CONFIG_SERIAL_CONSOLE
265 static void iss_console_write(struct console
*co
, const char *s
, unsigned count
)
269 if (s
!= 0 && *s
!= 0)
270 __simc (SYS_write
, 1, (unsigned long)s
,
271 count
< len
? count
: len
,0,0);
274 static struct tty_driver
* iss_console_device(struct console
*c
, int *index
)
277 return serial_driver
;
281 static struct console sercons
= {
283 .write
= iss_console_write
,
284 .device
= iss_console_device
,
285 .flags
= CON_PRINTBUFFER
,
289 static int __init
iss_console_init(void)
291 register_console(&sercons
);
295 console_initcall(iss_console_init
);
297 #endif /* CONFIG_SERIAL_CONSOLE */