| /* |
| * arch/xtensa/platforms/iss/console.c |
| * |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file "COPYING" in the main directory of this archive |
| * for more details. |
| * |
| * Copyright (C) 2001-2005 Tensilica Inc. |
| * Authors Christian Zankel, Joe Taylor |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/kernel.h> |
| #include <linux/sched.h> |
| #include <linux/console.h> |
| #include <linux/init.h> |
| #include <linux/slab.h> |
| #include <linux/mm.h> |
| #include <linux/major.h> |
| #include <linux/param.h> |
| #include <linux/serial.h> |
| #include <linux/serialP.h> |
| |
| #include <asm/uaccess.h> |
| #include <asm/irq.h> |
| |
| #include <platform/simcall.h> |
| |
| #include <linux/tty.h> |
| #include <linux/tty_flip.h> |
| |
| #ifdef SERIAL_INLINE |
| #define _INLINE_ inline |
| #endif |
| |
| #define SERIAL_MAX_NUM_LINES 1 |
| #define SERIAL_TIMER_VALUE (20 * HZ) |
| |
| static struct tty_driver *serial_driver; |
| static struct timer_list serial_timer; |
| |
| static DEFINE_SPINLOCK(timer_lock); |
| |
| int errno; |
| |
| static int __simc (int a, int b, int c, int d, int e, int f) __attribute__((__noinline__)); |
| static int __simc (int a, int b, int c, int d, int e, int f) |
| { |
| int ret; |
| __asm__ __volatile__ ("simcall\n" |
| "mov %0, a2\n" |
| "mov %1, a3\n" : "=a" (ret), "=a" (errno) |
| : : "a2", "a3"); |
| return ret; |
| } |
| |
| static char *serial_version = "0.1"; |
| static char *serial_name = "ISS serial driver"; |
| |
| /* |
| * This routine is called whenever a serial port is opened. It |
| * enables interrupts for a serial port, linking in its async structure into |
| * the IRQ chain. It also performs the serial-specific |
| * initialization for the tty structure. |
| */ |
| |
| static void rs_poll(unsigned long); |
| |
| static int rs_open(struct tty_struct *tty, struct file * filp) |
| { |
| int line = tty->index; |
| |
| if ((line < 0) || (line >= SERIAL_MAX_NUM_LINES)) |
| return -ENODEV; |
| |
| spin_lock(&timer_lock); |
| |
| if (tty->count == 1) { |
| init_timer(&serial_timer); |
| serial_timer.data = (unsigned long) tty; |
| serial_timer.function = rs_poll; |
| mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE); |
| } |
| spin_unlock(&timer_lock); |
| |
| return 0; |
| } |
| |
| |
| /* |
| * ------------------------------------------------------------ |
| * iss_serial_close() |
| * |
| * This routine is called when the serial port gets closed. First, we |
| * wait for the last remaining data to be sent. Then, we unlink its |
| * async structure from the interrupt chain if necessary, and we free |
| * that IRQ if nothing is left in the chain. |
| * ------------------------------------------------------------ |
| */ |
| static void rs_close(struct tty_struct *tty, struct file * filp) |
| { |
| spin_lock(&timer_lock); |
| if (tty->count == 1) |
| del_timer_sync(&serial_timer); |
| spin_unlock(&timer_lock); |
| } |
| |
| |
| static int rs_write(struct tty_struct * tty, |
| const unsigned char *buf, int count) |
| { |
| /* see drivers/char/serialX.c to reference original version */ |
| |
| __simc (SYS_write, 1, (unsigned long)buf, count, 0, 0); |
| return count; |
| } |
| |
| static void rs_poll(unsigned long priv) |
| { |
| struct tty_struct* tty = (struct tty_struct*) priv; |
| |
| struct timeval tv = { .tv_sec = 0, .tv_usec = 0 }; |
| int i = 0; |
| unsigned char c; |
| |
| spin_lock(&timer_lock); |
| |
| while (__simc(SYS_select_one, 0, XTISS_SELECT_ONE_READ, (int)&tv,0,0)){ |
| __simc (SYS_read, 0, (unsigned long)&c, 1, 0, 0); |
| tty_insert_flip_char(tty, c, TTY_NORMAL); |
| i++; |
| } |
| |
| if (i) |
| tty_flip_buffer_push(tty); |
| |
| |
| mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE); |
| spin_unlock(&timer_lock); |
| } |
| |
| |
| static void rs_put_char(struct tty_struct *tty, unsigned char ch) |
| { |
| char buf[2]; |
| |
| if (!tty) |
| return; |
| |
| buf[0] = ch; |
| buf[1] = '\0'; /* Is this NULL necessary? */ |
| __simc (SYS_write, 1, (unsigned long) buf, 1, 0, 0); |
| } |
| |
| static void rs_flush_chars(struct tty_struct *tty) |
| { |
| } |
| |
| static int rs_write_room(struct tty_struct *tty) |
| { |
| /* Let's say iss can always accept 2K characters.. */ |
| return 2 * 1024; |
| } |
| |
| static int rs_chars_in_buffer(struct tty_struct *tty) |
| { |
| /* the iss doesn't buffer characters */ |
| return 0; |
| } |
| |
| static void rs_hangup(struct tty_struct *tty) |
| { |
| /* Stub, once again.. */ |
| } |
| |
| static void rs_wait_until_sent(struct tty_struct *tty, int timeout) |
| { |
| /* Stub, once again.. */ |
| } |
| |
| static int rs_read_proc(char *page, char **start, off_t off, int count, |
| int *eof, void *data) |
| { |
| int len = 0; |
| off_t begin = 0; |
| |
| len += sprintf(page, "serinfo:1.0 driver:%s\n", serial_version); |
| *eof = 1; |
| |
| if (off >= len + begin) |
| return 0; |
| |
| *start = page + (off - begin); |
| return ((count < begin + len - off) ? count : begin + len - off); |
| } |
| |
| |
| static struct tty_operations serial_ops = { |
| .open = rs_open, |
| .close = rs_close, |
| .write = rs_write, |
| .put_char = rs_put_char, |
| .flush_chars = rs_flush_chars, |
| .write_room = rs_write_room, |
| .chars_in_buffer = rs_chars_in_buffer, |
| .hangup = rs_hangup, |
| .wait_until_sent = rs_wait_until_sent, |
| .read_proc = rs_read_proc |
| }; |
| |
| int __init rs_init(void) |
| { |
| serial_driver = alloc_tty_driver(1); |
| |
| printk ("%s %s\n", serial_name, serial_version); |
| |
| /* Initialize the tty_driver structure */ |
| |
| serial_driver->owner = THIS_MODULE; |
| serial_driver->driver_name = "iss_serial"; |
| serial_driver->name = "ttyS"; |
| serial_driver->major = TTY_MAJOR; |
| serial_driver->minor_start = 64; |
| serial_driver->type = TTY_DRIVER_TYPE_SERIAL; |
| serial_driver->subtype = SERIAL_TYPE_NORMAL; |
| serial_driver->init_termios = tty_std_termios; |
| serial_driver->init_termios.c_cflag = |
| B9600 | CS8 | CREAD | HUPCL | CLOCAL; |
| serial_driver->flags = TTY_DRIVER_REAL_RAW; |
| |
| tty_set_operations(serial_driver, &serial_ops); |
| |
| if (tty_register_driver(serial_driver)) |
| panic("Couldn't register serial driver\n"); |
| return 0; |
| } |
| |
| |
| static __exit void rs_exit(void) |
| { |
| int error; |
| |
| if ((error = tty_unregister_driver(serial_driver))) |
| printk("ISS_SERIAL: failed to unregister serial driver (%d)\n", |
| error); |
| put_tty_driver(serial_driver); |
| } |
| |
| |
| /* We use `late_initcall' instead of just `__initcall' as a workaround for |
| * the fact that (1) simcons_tty_init can't be called before tty_init, |
| * (2) tty_init is called via `module_init', (3) if statically linked, |
| * module_init == device_init, and (4) there's no ordering of init lists. |
| * We can do this easily because simcons is always statically linked, but |
| * other tty drivers that depend on tty_init and which must use |
| * `module_init' to declare their init routines are likely to be broken. |
| */ |
| |
| late_initcall(rs_init); |
| |
| |
| #ifdef CONFIG_SERIAL_CONSOLE |
| |
| static void iss_console_write(struct console *co, const char *s, unsigned count) |
| { |
| int len = strlen(s); |
| |
| if (s != 0 && *s != 0) |
| __simc (SYS_write, 1, (unsigned long)s, |
| count < len ? count : len,0,0); |
| } |
| |
| static struct tty_driver* iss_console_device(struct console *c, int *index) |
| { |
| *index = c->index; |
| return serial_driver; |
| } |
| |
| |
| static struct console sercons = { |
| .name = "ttyS", |
| .write = iss_console_write, |
| .device = iss_console_device, |
| .flags = CON_PRINTBUFFER, |
| .index = -1 |
| }; |
| |
| static int __init iss_console_init(void) |
| { |
| register_console(&sercons); |
| return 0; |
| } |
| |
| console_initcall(iss_console_init); |
| |
| #endif /* CONFIG_SERIAL_CONSOLE */ |
| |